Back

Physiological Measurement

○ IOP Publishing

Preprints posted in the last 7 days, ranked by how well they match Physiological Measurement's content profile, based on 14 papers previously published here. The average preprint has a 0.02% match score for this journal, so anything above that is already an above-average fit.

1
Clinicians Perspectives on Fighting the Ventilator

Olivier, L.; Madzhakova, D.; Lauterbach Oprea, C.; Stollenwerk, A.; Orlikowsky, T.; Schoberer, M.

2026-10-21 pediatrics 10.64898/2026.10.20.26365990 medRxiv
Top 0.1%
3.3%
Show abstract

Introduction: Fighting the ventilator (FV) is characterized by a patients active counteraction of respiratory gas flow across multiple breaths during mechanical ventilation. An effective ventilation is prevented during such episodes. The objective of this exploratory study was to evaluate clinicians knowledge, perception and agreement regarding this condition. Methods: In a cross-sectional online survey, medical professionals with experience in intensive care medicine (mostly neonatal and pediatric patients) responded to 11 questions covering various clinical aspects of FV. Results: All respondents were familiar with the phenomenon and assessed it to be clinically relevant. Neonates were perceived to be predominantly affected. Promoting factors of FV included inadequate sedation and ventilation-associated factors. In clinical practice, the participants identified FV by clinical evaluation, analysis of ventilator waveforms and capnography and used both pharmacological and non-pharmacological intervention strategies. There was no consensus concerning the English terminology of the condition. Only few respondents were familiar with local guidelines to manage FV. Conclusion: Although there was consensus on the relevance of FV, diagnostics and management strategies were highly heterogeneous. Many participants agreed that poor patient-ventilator synchrony was an important cause of FV. Future work should focus on characterizing and generating evidence on FV.

2
Sedatives reduce human gastric slow-wave amplitude, assessed by a multicenter study of endoscopic gastric mapping

Tremain, P.; Dowrick, J.; Chan, C.-H. A.; Rowbotham, D.; Lim, G.; O'Grady, G.; Cheng, L. K.; Mckeage, J.; Angeli-Gordon, T. R.

2026-10-20 gastroenterology 10.64898/2026.10.15.26365429 medRxiv
Top 0.1%
2.8%
Show abstract

Background: Gastrointestinal (GI) motility disorders are prevalent, impose a significant burden, and are associated with disrupted spatial propagation of bioelectrical gastric slow waves. High-resolution endoscopic gastric mapping (EGM) is an emerging minimally invasive technique for imaging gastric electrical activity; however, EGM is performed alongside standard gastroscopy and requires procedural sedation, which may interact with gastric electrical activity, distorting clinical insights. This study explored the influence of procedural sedation on EGM-recorded slow-wave activity. Methods: EGM was performed for {approx}7 min in 32 patients undergoing upper GI endoscopy at two New Zealand hospitals. Endoscopists administered procedural sedation (fentanyl and midazolam) according to best clinical practice. The relationship between slow-wave amplitude and patient characteristics was then investigated using a variety of statistical techniques. Key Results: Gastric slow waves were detected in 30 of 32 patients who underwent EGM. Symptom scores and demographic measures were comparable between sites. Fentanyl (A, 93.4 {+/-} 13.7 g vs B, 137.5 {+/-} 33.7 g, p[≤]0.001) and midazolam (A, 5.0 {+/-} 0.9 mg vs B, 7.4 {+/-} 1.6 mg, p[≤]0.001) doses were higher at Hospital B than Hospital A. Correspondingly, slow-wave amplitudes were lower at Hospital B than Hospital A (A, 2.33 {+/-} 1.61 mV vs B, 0.86 {+/-} 1.01 mV, p=0.004). All other slow-wave metrics were consistent between hospitals. Combined sedative dose was negatively correlated with slow-wave amplitude (p=0.037). Conclusions & Inferences: Higher procedural sedative doses are associated with lower-amplitude gastric slow-waves. Procedural sedation dose and opiate administration should be carefully considered when interpreting GI electrophysiology measurements.

3
Heart rate variability and electrocardiographic parameters among workers exposed to chronic intermittent hypobaric hypoxia in the Peruvian Andes: A cross-sectional study Cardiac autonomic function in Andean workers

Montes-Madariaga, E. S.; Ortiz-Saavedra, J. B.; Mamani Castillo, J. S.; Valencia-Pacheco, A. I.; Ballon Echegaray, J. A.; Paz Torres, I. L.; Leon Vasquez, R. A. J.

2026-10-16 cardiovascular medicine 10.64898/2026.10.15.26365599 medRxiv
Top 0.3%
1.2%
Show abstract

Chronic intermittent hypobaric hypoxia is an occupational exposure experienced by workers who alternate between high-altitude worksites and lower-altitude resting locations. Its effects on cardiac autonomic modulation and electrocardiographic parameters remain insufficiently characterized in Andean workers. This study aimed to compare heart rate variability and electrocardiographic parameters between workers exposed to chronic intermittent hypobaric hypoxia and controls working permanently at lower altitude in Arequipa, Peru. An observational cross-sectional study was conducted in 96 male workers aged 20-60 years. The exposed group included 53 workers performing rotational shifts at altitudes [&ge;]3,000 m above sea level with rest periods at <2,500 m, while the control group included 43 workers working permanently at <2,500 m. Heart rate variability was assessed during the morning rest period in Arequipa, at approximately 2,300 25 m above sea level, using a Polar(R) H10 heart rate sensor after 15 minutes of rest. Participants also underwent standard 12-lead electrocardiography. Vital signs were clinically similar between groups. No statistically significant differences were observed in PR interval, corrected QT interval, time-domain heart rate variability parameters, or frequency-domain heart rate variability parameters. In this sample of apparently healthy male workers evaluated during their rest period at moderate altitude, exposure to chronic intermittent hypobaric hypoxia was not associated with significant differences in resting heart rate variability or standard electrocardiographic parameters.

4
Teaching an ECG model where to look does not make it more robust to missing leads: a pre-registered comparison of guideline-based attention guidance with random lead masking

BOU ALI, M. N.; Mahmoud, M.

2026-10-19 cardiovascular medicine 10.64898/2026.10.17.26365795 medRxiv
Top 0.4%
1.0%
Show abstract

Background. Real-world 12-lead electrocardiograms (ECGs) often have missing or corrupted leads. A deep-learning classifier can be prepared for this by random lead masking during training, or by injecting clinical knowledge, for example by pulling its attention towards the leads that guidelines use for each diagnosis. Whether this knowledge adds robustness beyond masking is unknown. Methods. Pre-registered comparison of three arms sharing one network (per-lead 1D-ResNet encoder and per-diagnosis attention over the 12 leads): standard training (M0); random whole-lead masking (M1); masking plus a Kullback-Leibler penalty pulling attention towards a fixed guideline-derived key-lead map (M2, guideline-based attention guidance). Six diagnoses; five seeds per arm. Development on PTB-XL (21,799 ECGs); single sealed evaluation on PTB-XL fold 10 (2,198 ECGs) and on CODE-15% (233,204 exams, external validation). Primary endpoint: AUROC difference M2 - M1, averaged over first-degree AV block, right and left bundle branch block and atrial fibrillation and over 1 to 6 lost (zeroed) leads, with a patient-level paired BCa bootstrap 95% confidence interval. Results. The guidance did not change robustness: {Delta}AUROC -0.0010 (95% CI -0.0033 to +0.0006), an interval entirely within the pre-specified +-0.02 margin; the result was unchanged with another bootstrap seed, other interval methods and leave-one-diagnosis-out analyses. Masking improved AUROC: M1 - M0 = +0.0134 (95% CI +0.0102 to +0.0172) when one key lead was lost, and the number of lost leads tolerated before AUROC fell by more than 0.02 rose from 7 (M0) to 10 (M1). M2 attention matched the map and M2 was non-inferior on intact ECGs, but its calibration slope was lower for all six diagnoses in both datasets. M2 lost slightly more when all key leads were lost together (-0.0067) and gained only when one to three leads remained (exploratory; AUROC 0.9408 vs 0.9210 with 11 leads lost). CODE-15% reproduced every pattern (primary -0.0007, 95% CI -0.0011 to -0.0003). Conclusions. Random lead masking suffices to make an ECG classifier robust to missing leads; adding guideline knowledge aligns attention with clinical criteria but adds no robustness and worsens calibration. Guideline-aligned attention should not be taken as evidence of robustness.

5
Plantar Thermography for Longitudinal Remote Monitoring of Chronic Heart Failure

Esposito, M. L.; Xuan, L.; Zemp, E.; Zile, M. R.; Tedford, R. J.; Linders, D.; Prins, K. W.

2026-10-21 cardiovascular medicine 10.64898/2026.10.20.26364428 medRxiv
Top 0.5%
0.6%
Show abstract

Rural patients with heart failure (HF) have poor access to care, worse outcomes, and may benefit from at-home monitoring. We evaluated whether foot temperature measured using a thermographic floor mat was associated with invasively measured cardiac output and whether longitudinal temperature changes preceded HF events. We conducted a two-part prospective, observational single-center study using the SmartMat (Podimetrics, Somerville, MA), which acquires plantar thermograms and ambient temperature. In the acute study, patients undergoing clinically indicated right heart catheterization completed 4 scans on the same day. In the chronic study, patients with a HF hospitalization in the past year and New York Heart Association Class II-III symptoms were instructed to use the device and a scale daily for 6 months. A HF event was defined as receiving at least one dose of intravenous or subcutaneous diuretic. Thirty patients were enrolled in the acute study. Mean right hallux temperature positively correlated with thermodilution cardiac output (r=0.63, p<0.001). 42 patients were enrolled in the chronic study. Among patients experiencing an HF event, ambient-adjusted hallux temperature declined in the 15 days immediately preceding the event compared with days 15-30 before the event. Plantar thermograms are associated with invasively measured cardiac output and may detect subclinical worsening before HF events. Foot temperature may provide complementary information regarding HF decompensation, supporting further evaluation of plantar thermography for remote HF monitoring.

6
Fully Automated Multi-Chamber Strain Profiling in Consecutive Patients Undergoing Transthoracic Echocardiography: Feasibility, Functional Clustering, and Prognostic Implications

Noh, S. A.; Park, J.; Yoon, Y. E.; Jeon, J.; Jang, Y.; Lee, S.-A.; Bak, M.; Choi, H.-M.; Hwang, I.-C.; Cho, G.-Y.

2026-10-21 cardiovascular medicine 10.64898/2026.10.20.26365880 medRxiv
Top 0.5%
0.6%
Show abstract

Aims: Myocardial strain enables sensitive assessment of cardiac function, but its clinical application has largely focused on individual chambers or selected patient populations. We evaluated the feasibility and clinical relevance of fully automated multi-chamber strain assessment in consecutive patients undergoing routine transthoracic echocardiography (TTE). Methods and results: This retrospective study included 8,350 consecutive adults undergoing TTE. A hospital-wide artificial intelligence (AI)-based system automatically measured left ventricular (LV) global longitudinal strain (LVGLS), left atrial (LA) reservoir strain (LASr), and right ventricular (RV) free-wall strain (RVFWS). AI-derived LVGLS was available from at least one apical view in 97.1% of patients and from all three views in 94.8%; LASr and RVFWS were available in 94.1% and 94.5%, respectively, resulting in complete multi-chamber strain assessment in 90.3%. Strain measures showed modest correlations with conventional chamber-specific echocardiographic parameters and differential associations with clinical outcomes. Gaussian mixture modeling identified three distinct clusters characterized by preserved multi-chamber function, RV-dominant dysfunction, and pan-chamber dysfunction. Compared with the preserved cluster, pan-chamber dysfunction was associated with the highest risk of all-cause death or heart failure hospitalization (adjusted hazard ratio, 3.44; 95% CI, 2.43-4.88; P<0.001). Prognostic associations remained evident in patients with LV ejection fraction (LVEF) [&ge;]50%, and cluster assignment provided incremental prognostic information beyond clinical factors, LVEF, and RV fractional area change. Conclusions: Fully automated multi-chamber strain assessment was feasible in a large consecutive TTE cohort. Integrating strain across cardiac chambers may provide complementary functional characterization and identify clinically relevant clusters with prognostic information beyond conventional assessment.

7
Narrow Is Slow: CT-Derived Anatomic Isthmus 3 Width and Arrhythmogenic Substrate in Repaired Tetralogy of Fallot

Kosmopoulos, M.; Liskov, S.; Amir, R.; Berger, R. D.; Cedars, A.; Chehab, O.; Chrispin, J.; Fisher, S.; Fuller, S.; Fraint, H.; Armstrong, A. K.; Ziakas, I.; Aronis, K. N.

2026-10-19 cardiovascular medicine 10.64898/2026.10.16.26365751 medRxiv
Top 0.7%
0.4%
Show abstract

Background: Anatomic isthmus 3 (AI 3) is defined as the myocardium between the pulmonary valve annulus and the ventricular septal defect patch that persists after tetralogy of Fallot (ToF) repair. Ventricular tachycardia (VT) propagated through slow conducting AI 3 (SCAI 3) represents a significant cause of morbidity in ToF. There is an unmet need for non-invasive identification of SCAI 3 in patients with ToF. Objectives: To assess whether the anatomic features of AI 3 as derived from cardiac computed tomography (CT) can predict slow conduction velocity during EP study. Methods: This retrospective single-center study included patients with ToF who underwent an electrophysiologic study and had AI 3 width measured from the pre-procedure cardiac CT. All patients underwent programmed ventricular stimulation, and electroanatomic. Logistic regression was performed to assess the relationship between AI 3 width and the presence of SCAI 3. Results: Of 27 consecutive patients with ToF, twelve patients were found to have SCAI 3, and ten patients were found to have SCAI 3 mediated VT. The AI 3 was significantly narrower in patients with SCAI 3 compared to those with normal AI 3 conduction (18.4 +/- 6.6 mm vs. 29.2 +/- 9.0 mm; p = 0.001). An AI 3 width above 21.5 mm carried a negative predictive value of 80.0%. Conclusion: In adults with repaired ToF referred for electrophysiology study, a narrower CT-derived AI 3 width was associated with SCAI 3 identification. AI 3 width measured on a CT obtained before PV replacement could help guide invasive risk stratification.

8
Pre-Deployment Cardiovascular Risk Assessment and Outcomes among United States Antarctic Program Participants: Insights from Contemporary Risk Models

LeBlanc, D. P.; Qadeer, A.; Krishna, S. R. G.; Forrester, A.; Patel, A.; Shi, D.; Nagueh, E.; Hsu, J.; Bhobe, N.; Gaalema, D. E.; McKeith, J.; Jneid, H.; Allencherril, J.

2026-10-16 cardiovascular medicine 10.64898/2026.10.14.26365580 medRxiv
Top 0.7%
0.4%
Show abstract

Background: Cardiovascular (CV) screening is critical for personnel deploying to Antarctica, where geographic isolation and limited medical care make the management of acute cardiovascular events challenging. The utility of contemporary risk prediction tools such as the AHA PREVENT equations in this unique population remains uncertain. Methods: We retrospectively analyzed 154 individuals referred for enhanced CV evaluation before deployment to the U.S. Antarctic Program (USAP). Participants were evaluated across three temporal cohorts (2018-2020, 2021-2023, and 2024-2026). Demographics, CV risk factors, cardiac testing, and deployment clearance outcomes were collected. Risk was estimated using the Framingham Risk Score (FRS), AHA/ACC Pooled Cohort Equations (PCE), and AHA PREVENT risk models. Results: The cohort was predominantly male (79.9%; mean age 44.6 {+/-} 14.6 years), and abnormal ECG was the most common referral trigger (70.8%). Median 10-year risk was low by PREVENT and FRS and borderline elevated by PCE (PREVENT 2.7% [IQR 1.1-6.6], FRS 2.3% [IQR 0.5-7.1], and PCE 6.1% [IQR 2.4-9.2]). Among 72 participants with all scores, 51% were classified discordantly; PREVENT ASCVD agreed closely with FRS (=0.77) but poorly with PCE (=0.24-0.35), which consistently estimated higher risk. PCE was calculable in 52.6% versus 70.8% for PREVENT. Overall, 132 participants (85.7%) were cleared for deployment, while 8 (5.2%) were not physically qualified (NPQ); 6 of these NPQs were due to cardiovascular causes. Of 22 cardiac medical evacuations during the study period, 21 involved individuals without prior advanced cardiovascular screening. One screened individual was evacuated for symptoms subsequently found to have no cardiac cause. Conclusions: Risk calculators disagree substantially in the fitness-selected population. We recommend PREVENT as the primary risk-stratification tool as it is the most contemporary derivation, incorporates renal function, is race-agnostic, extends to heart failure, applies from age 30, and agrees closely with FRS, easing transition. Targeted imaging, including coronary artery calcium scoring, may supplement intermediate-risk candidates.

9
Deep learning-based electrocardiographic differentiation of Takotsubo syndrome from acute anterior myocardial infarction: explainability, human-AI interaction, and a utilization bias hypothesis

Kagawa, E.; Kato, M.; Hidaka, T.; Kunita, E.; Hironobe, N.; Matsui, S.; Kobayashi, Y.; Uotani, Y.; Teramoto, T.; Yoshii, K.; Okumoto, T.; Tani, M.; Dote, K.

2026-10-19 cardiovascular medicine 10.64898/2026.10.15.26365116 medRxiv
Top 0.9%
0.3%
Show abstract

Background: Artificial intelligence (AI) may improve electrocardiographic differentiation of Takotsubo syndrome from acute anterior ST-segment elevation myocardial infarction (STEMI), but its impact on human diagnostic performance, the added value of visual explanations, and differences by reader background and experience remain uncertain. Methods: Using 12-lead electrocardiogram (ECG) images from two hospitals, we developed and externally validated an ensemble of three deep learning models after self-supervised pretraining and fine-tuning. The diagnostic task used ECGs recorded within 14 days after symptom onset, regardless of reperfusion status. We conducted a four-phase reader study. Phases 1-3 compared unaided interpretation, a reference sheet, and additional AI assistance. In Phase 4, readers evaluated a new ECG set after randomization to reference-sheet support alone, with AI predictions, or with AI predictions plus gradient-weighted class activation mapping (Grad-CAM) heatmaps. Diagnostic correctness was analyzed using generalized linear mixed-effects models. Exploratory analyses examined differences by cardiologist status and experience. Results: Development and external-validation cohorts, including healthy controls, comprised 832 and 95 participants, respectively. For Takotsubo-STEMI discrimination, external-validation accuracy was 0.914, with areas under the receiver operating characteristic and precision-recall curves of 0.970 and 0.984. Seventy healthcare providers completed the reader study. The estimated probability of correct diagnosis increased from 0.632 without assistance to 0.864 with AI assistance (odds ratio [OR], 3.71; P<0.001). In randomized Phase 4, AI assistance improved accuracy vs reference-sheet support alone (OR, 4.28; 95% CI, 3.08-5.95; P<0.001), and Grad-CAM provided additional benefit (OR, 1.53; 95% CI, 1.04-2.25; P=0.033). Exploratory analyses showed greater improvement among less experienced readers; with AI assistance, non-cardiologists outperformed cardiologists. AI-assisted readers remained less accurate overall than the model alone. Conclusions: An ECG image-based ensemble differentiated Takotsubo syndrome from anterior STEMI and improved reader accuracy. Visual explanations provided additional benefit, while experience-related differences highlight the importance of effective human-AI interaction.

10
Cardiac MRI at 3.0T in the presence of implantable cardioverter defibrillators (ICDs)

Reiter, T.; Weber, O. M.; Weiss, i.; Kraus, N.; Kress, S.; Bauer, W. R.

2026-10-21 cardiovascular medicine 10.64898/2026.10.16.26364740 medRxiv
Top 1%
0.2%
Show abstract

Patients with implantable cardioverter-defibrillators (ICDs) often are excluded from receiving CMR scans at 3.0T due to ICD-induced image artifacts. This work aims to transfer sequence protocols established for CMR imaging in the presence of ICDs at 1.5T to a first human application at 3.0T. All measurements were performed on a clinical 3T MRI scanner. Phantom measurements were used to establish and optimize wideband PSIR LGE imaging at 3.0T. Volunteer measurements with externally placed ICDs were used for optimization of CINE imaging and wideband PSIR imaging. Thirdly, patients with implanted ICD were examined with the optimized protocols. Human measurements showed that SA stacks obtained with spoiled GRE after contrast agent showed a markedly lower artifact burden than the conventional approach. For scar imaging, a wideband PSIR with a bandwidth of 3kHz and a frequency offset of +750Hz allowed a sufficient suppression of relevant artifacts in the majority of scans. No strong correlation between the image quality and the distance between the cardiac silhouette and the device was detected. The presented work shows the feasibility of clinical cardiac MRI at 3.0T including GRE-CINE and wideband PSIR-LGE for patients with ICDs.

11
Left Ventricular Diastolic Intraventricular Pressure Differences and Propagation Velocity with 4D-Flow MRI in Patients with Hypertrophic Cardiomyopathy

Stipechi, L. V.; Craiem, D.; Gencer, U.; Casciaro, M. E.; Hulot, J.-S.; Hagege, A.; Soulat, G.; Mousseaux, E.

2026-10-21 cardiovascular medicine 10.64898/2026.10.15.26365692 medRxiv
Top 1%
0.2%
Show abstract

Background: Transthoracic echocardiography (TTE) remains the gold standard for assessing left ventricular (LV) diastolic dysfunction (DD), but noninvasive alternatives are needed to overcome geometric and acoustic limitations. 4D-Flow MRI enables comprehensive assessment of intraventricular pressure differences (IVPDs) and flow propagation velocity (VP). We aimed to evaluate 4D-Flow-derived IVPDs and VP in patients with hypertrophic cardiomyopathy (HCM). Methods: Thirty-eight HCM patients and 38 age- and sex-matched healthy controls underwent TTE and 4D-Flow MRI. Spatiotemporal maps of velocity and IVPDs, decomposed into inertial and convective components, were derived along the main inflow streamline from the mitral valve to the apex. Peak early filling rate (PEFR) was used to normalize IVPDs and VP. Results: While absolute peak flow rates were comparable, HCM patients exhibited significantly faster VP (100.4 vs. 60.2 cm/s, p < 0.01) and higher positive early E IVPD (1.40 vs. 0.92 mmHg, p < 0.01) compared to controls. Normalizing IVPDs by PEFR amplified group differences, revealing a markedly increased flow-normalized E-IVPD (5.13 vs. 2.94 x 103 mmHg.ml1.s, p < 0.001) and deeper reverse ER IVPD (-6.06 vs. -4.61 x 103 mmHg.ml1.s, p < 0.01) in HCM. These differences were primarily driven by the inertial components. Multivariable analysis demonstrated that ER IVPD is independently determined by PEFR and the TTE E/E' ratio (r = 0.65, p < 0.001). Conclusions: 4D-Flow MRI-derived, flow-normalized IVPDs and propagation velocity provide robust, noninvasive markers of altered LV chamber stiffness and impaired diastolic filling in HCM, offering deeper 3D hemodynamic insights into diastolic dysfunction.

12
Understanding Psychological Health in Adults with Irritable Bowel Syndrome: A Cross-Sectional Study Using the All of Us Research Program

Wu, W.; Li, A.; Chen, J.; You, E.; Liu, P.; Rodriguez, L.; Chen, M.-H.; Cong, X.

2026-10-21 gastroenterology 10.64898/2026.10.20.26365988 medRxiv
Top 1%
0.2%
Show abstract

Background: Psychological health is an important aspect of health and well-being among adults with irritable bowel syndrome, yet the interrelationships among individual vulnerabilities, social experiences, perceived stress, and psychological health outcomes remain poorly understood. Objective: To characterize psychological health and examine direct and indirect associations of childhood adversity and adult attention-deficit/hyperactivity disorder-related symptoms within an adapted Stress Process Model. Design: Cross-sectional secondary analysis. Setting: The United States All of Us Research Program. Participants: 2,417 adults with electronic health record-documented irritable bowel syndrome and complete data on the primary analysis variables and covariates. Methods: Separate structural equation models examined childhood adversity and adult attention-deficit/hyperactivity disorder-related symptoms in relation to perceived stress, anxiety and depressive symptoms, and positive psychological well-being, with loneliness and perceived social support as psychosocial pathways. Models adjusted for sociodemographic and social-context factors. Results: The median age was 54.39 years; 80.7% were female and 84.4% were White. Moderate-to-high perceived stress was reported by 56.2%, at least moderate anxiety symptoms by 21.0%, and at least moderate depressive symptoms by 24.3%. Higher ACE-8 scores were associated with greater perceived stress, anxiety symptoms, and depressive symptoms and lower psychological well-being ({beta} = 0.063, 0.089, 0.116, and -0.100, respectively); corresponding associations for higher ASRS-6 scores were {beta} = 0.299, 0.355, 0.390, and -0.260. Loneliness-specific indirect associations were positive for perceived stress, anxiety, and depressive symptoms (ACE-8: {beta} = 0.023-0.034; ASRS-6: {beta} = 0.043-0.075) and negative for psychological well-being (ACE-8: {beta} = -0.039; ASRS-6: {beta} = -0.089; all p < .001). Social support-specific indirect associations were not significant in the ACE-8 model and were small and significant only for anxiety and depression in the ASRS-6 model ({beta} = 0.003-0.004). Conclusions: Psychological health among adults with irritable bowel syndrome was associated with interconnected individual and social factors within an adapted Stress Process Model. Childhood adversity and adult attention-deficit/hyperactivity disorder-related symptoms showed direct and indirect associations with psychological health, with loneliness emerging as the most consistent social factor. These findings support prospective investigation of individual vulnerabilities and social experiences in psychological health. The cross-sectional design does not establish temporal ordering or causal mediation.

13
Normative Temperature, Demographic Categories, and the Limits of Infrared Thermometry

Lohier, A.; Campbell, A. G.; Chartash, D.

2026-10-21 health informatics 10.64898/2026.10.19.26365925 medRxiv
Top 1%
0.1%
Show abstract

Objective. Temperature readings are routinely stratified by race and ethnicity, though significant group differences may reflect physiology, instrument noise, or categorization rather than biology. This study tests whether these categories partition facial infrared thermography measurements beyond individual variation and baseline device noise. Approach. A secondary analysis of thermography data (n = 951 adults) compares inner-canthus maximum (TCEmax) and full-face maximum (Tmax) temperatures across five administrative categories via one-way analysis of variance (ANOVA), mixed-effects modeling, Bland-Altman analysis against oral reference, and Monte Carlo sensitivity analysis. Main results. ANOVA returns significant group differences (p < 0.001; eta-squared = 0.04 for TCEmax, 0.03 for Tmax), but the total spread (0.2 to 0.3 degrees Celsius) is comparable to device accuracy and within-subject variability. Individual variation accounts for 95% of TCEmax variance, and adding simulated Gaussian noise to participant-level temperatures (sigma = 0.10 to 0.30 degrees Celsius) preserves the complete group-mean rank order in as few as 37.5% of iterations. Significance. Testing whether a group difference survives perturbation at the scale of instrument accuracy offers a check against treating significance alone as evidence of physiology. Here, observed group differences are small relative to measurement variability, and their physiological interpretation remains uncertain, with implications for clinical tools that treat administrative categories as biologically meaningful.

14
Trends and Disparities in Respiratory Failure Mortality with Co-Listed Atrial Fibrillation and Flutter Among U.S. Adults Aged >= 65 Years, 1999 to 2024, with AAMR Forecasts Through 2035: A CDC Wonder Analysis

Seher, W.; Masood, H. A.; Jamil, A.; Fiza, S.; Jehangir, A.; Hafeez, R.; Arbab, M.; Ahmad, R.; Ullah, H.; Sharma, S. P.

2026-10-16 respiratory medicine 10.64898/2026.10.15.26365608 medRxiv
Top 2%
0.1%
Show abstract

Abstract Background: Respiratory failure (RF) and atrial fibrillation/flutter (AF/AFL) often occur together in older adults, but long-term national mortality trends for the two conditions combined have not been described. We examined trends and disparities in deaths with co-listed RF and AF/AFL among U.S. adults aged 65 years and older from 1999 to 2024, and projected rates through 2035. Methodology: We used the CDC WONDER Multiple Cause of Death database to identify deaths with ICD 10 codes J96 (RF) and I48 (AF/AFL) listed together. Age-adjusted mortality rates (AAMRs) per 100,000 were standardized to the 2000 U.S. population and stratified by sex, race/ethnicity, census region, urbanization, state, and place of death. Joinpoint regression was used to estimate annual percent changes (APCs) and average annual percent changes (AAPCs). Forecasts for 2025 to 2035 were generated with an exponential smoothing (ETS) model. Results: A total of 433,598 deaths were recorded. The overall AAMR rose from 12.8 in 1999 to 66.7 in 2024 (AAPC 8.11%; 95% CI, 7.35 to 8.87; P < 0.0001). Three segments were identified: an increase from 1999 to 2018 (APC 7.73%), a sharp rise from 2018 to 2021 (APC 18.10%), and a decline from 2021 to 2024 (APC -5.25%). Males had a higher AAMR and a steeper increase than females (AAPC 8.44% vs 7.81%). Non-Hispanic White adults had the highest mean AAMR, Hispanic adults had the largest relative increase (AAPC 8.72%), and Non-Hispanic Asian/Pacific Islander adults had the smallest (AAPC 6.23%). The Midwest had the fastest regional growth (AAPC 9.35%). From 1999 to 2020, non-metropolitan areas increased faster than metropolitan areas (AAPC 10.09% vs 8.21%). State AAMRs ranged from 24.7 in Ohio to 85.1 in Louisiana. Most deaths occurred in hospital inpatient settings (64.1%), followed by nursing homes (14.1%) and the home (11.9%). The model projects an AAMR of 122.96 per 100,000 by 2035 (95% prediction interval, 85.42 to 160.50). Conclusions: Mortality involving RF with AF/AFL among older U.S. adults increased more than fivefold over 25 years, with a marked surge during the COVID 19 period and only a partial decline afterward. Differences by sex, race/ethnicity, region, and urbanization point to groups that may benefit from earlier detection and coordinated cardiopulmonary care.

15
What are the experiences, perceptions and training needs of inpatient general nursing staff on Continuous Glucose Monitoring?

Donat Ergin, B.; Mattishent, K.; Holder, D.; Minihane, A. M.; Kelly, B.; Holt, R.; Murphy, H.; Dhatariya, K.; Hornberger, M.

2026-10-15 nursing 10.64898/2026.10.14.26365417 medRxiv
Top 2%
0.1%
Show abstract

Background: Although point-of-care testing is the standard method for inpatient glucose monitoring; it is associated with patient discomfort and late detection of dysglycaemic events. Continuous glucose monitoring (CGM) may improve glycaemic management; however, limited staff education and experience among may hinder its implementation. Aim: To investigate experience, perceptions and training needs on CGM use among inpatient nursing staff across diverse hospital wards. Methods: This is a single-centre, 38-item online survey recruited inpatient nurses in a hospital in the UK. Participants were invited via the e-newsletter and posters; the survey remained open for five months. Results: Nineteen nurses reported positive perceptions of inpatient CGM. Most considered CGM reliable (77.8%) and preferred CGM combined with POCT (66.7%). Views on its impact on workload and patient-room entries were mixed (30% agreed, 30% disagreed). Training needs included sensor placement (92.9%) and alarm management (78.6%). Conclusion: Nurses viewed CGM favourably but highlighted important training needs for inpatient use.

16
Network representations of digital clock drawings for cognitive impairment detection

Pinheiro, A.; Cheng, H.; Karjadi, C.; Gifford, K.; Demissie, S.; Lunetta, K. L.; Liu, C.; Au, R.; Mohammed, S.

2026-10-19 health informatics 10.64898/2026.10.15.26365699 medRxiv
Top 2%
0.1%
Show abstract

INTRODUCTION: The digital clock drawing test (dCDT) is a cognitive screening tool capturing high-resolution pen-movement data. Existing approaches for classifying cognitive impairment from dCDTs rely on selected features or image-based methods. We propose representing dCDTs as structural networks to classify cognitive impairment and characterize spatial organization in clock drawings. METHODS: Weighted networks were constructed from 3,362 Framingham Heart Study participants, with and without cognitive impairment. Network representations were generated separately for command and copy conditions, with nodes representing pre-defined clock components (digits, hands, clock face) and edges capturing pairwise spatial relationships between components. Random forest models and graph convolutional networks were trained to predict cognitive impairment from the networks. Models were benchmarked against demographics-only and established summary feature baselines. RESULTS: Network-based models achieved AUC values comparable to the established summary feature baseline across command-only and copy-only conditions. Differences in spatial organization between the cognitively intact and impaired groups were greatest in the upper-right clock region, involving digits 1 and 2, the clock hands, and the surrounding clock face. Differences between the command and copy networks were larger among cognitively impaired participants. DISCUSSION: The proposed network representations provide an objective, scalable, and flexible framework for representing clock drawings for use in classification models. dCDT networks matched the predictive performance of established summary feature-based approaches and identified clock regions where spatial organization differed by cognitive status. After external validation, this approach has the potential to be incorporated within a clinical workflow to support automated and interpretable cognitive screening.

17
Evd Duration In Aneurysmal Subarachnoid Haemorrhage: A Single Centre Retrospective Cohort Study

Verma, A.; Davidson, K.; Fitzgerald, E.; Donaldson, L.; Garside, T.; Elliott, R.; Bass, F.; Hammond, N. E.; Kabir, A.; Delaney, A.

2026-10-21 intensive care and critical care medicine 10.64898/2026.10.18.26365822 medRxiv
Top 2%
0.1%
Show abstract

Introduction and objectives Hydrocephalus is a common complication of aneurysmal subarachnoid haemorrhage. This is one of several standard indications for the insertion of an external ventricular drain, but there are no standard guidelines for timing of extraventricular drain discontinuation in this population. Therefore, the study aims were to examine the 1) factors associated with extraventricular drain duration in aneurysmal subarachnoid haemorrhage and 2) association between extraventricular drain duration and clinical and resource-based outcomes. Methods In this single centre retrospective cohort study, data for adult patients treated in the ICU between 2015-2023 with aneurysmal subarachnoid haemorrhage and requiring an extraventricular drain were analysed. Data were extracted from both a prospective patient registry and the electronic medical record. Linear regression modelling was used to identify the factors associated with extraventricular drain duration. Measures used to examine the association between extraventricular drain duration, and the outcomes of interest included hazard ratio, relative risk, and mean differences as appropriate for a specific outcome. Results Of the participants (n=205), 68% (n = 140) were female, mean age was 60.7 (SD 13.3) years and 71% (n = 145) had a modified Fisher score of 4. Mean extraventricular drain duration was 15.3 (SD 8.6) days. The number of days mechanically ventilated and extraventricular drain challenge by clamp trial were associated with an increased duration of extraventricular drain treatment. Increased extraventricular drain duration was associated with an increased incidence of ventriculoperitoneal shunt insertion, and an increase in ICU and hospital length of stay when extraventricular drain duration exceeded 20 days. Conclusion The factors associated with an increased duration of extraventricular drain treatment were a longer duration of mechanical ventilation. The outcomes associated with an increased duration of extraventricular drain treatment were an increased incidence of ventriculoperitoneal shunt insertion, an increased incidence of ventriculitis when extraventricular drain duration exceeded 20 days, and an increase in ICU length of stay. These study findings may inform the conduct of a larger multi-centre study to examine the factors associated with duration of treatment with extraventricular drain, and outcomes associated with extraventricular drain duration.

18
Longitudinal changes in motor network activity and connectivity in patients with suspected Transcient Ischemic Attack: an exploratory fMRI study

Charbonnier, G.; Bonnet, L.; Comte, A.; Medeiros de Bustos, E.; Lesourd, M.

2026-10-19 neurology 10.64898/2026.10.13.26365278 medRxiv
Top 3%
0.0%
Show abstract

Background and Objectives Transient ischemic attack (TIA) diagnosis is challenging because it relies mainly on clinical assessment and exclusion of common differential. Functional MRI (fMRI) may provide a diagnostic biomarker by detecting transient brain dysfunction not visible on conventional imaging. This pilot study aimed to characterize acute motor-task BOLD activation in patients with suspected DWI-negative TIA and compare functional patterns between confirmed TIA and alternative diagnoses. Secondary objectives were to assess longitudinal changes in activation and connectivity at 3 months. Methods In this prospective single-center study, adults presenting within 24 h of transient anterior-circulation neurological symptoms underwent conventional MRI and additional motor-task fMRI. Patients with acute DWI lesions were excluded. Final diagnosis was established after 3-month follow-up. Whole-brain analyses, individualized motor cortex region-of-interest (ROI) analyses, and generalized psychophysiological interaction (gPPI) connectivity analyses were performed during the acute phase and at 3 months. Results Eight patients were enrolled; six had complete longitudinal imaging data and were included in the final analyses. Final diagnoses were TIA (n=2), migraine aura (n=2), functional neurological disorder (n=1), and hypoglycemia (n=1). Whole-brain and ROI analyses showed reduced bilateral motor-related BOLD responses during the acute phase in both TIA patients and in the patient with hypoglycemia. In contrast, patients with migraine and functional neurological disorder exhibited less marked longitudinal changes. In TIA patients, motor cortex activation increased at 3 months, tending to normalize toward values observed in non-TIA participants. Connectivity analyses revealed heterogeneous patterns, but the 2 TIA patients demonstrated increased longitudinal connectivity between the motor cortex contralateral to symptoms and other sensorimotor regions, including supplementary motor, premotor, parietal, and postcentral cortices. Discussion These preliminary findings suggest that TIA may be associated with transient bilateral reductions in motor-network activity. Functional abnormalities appeared to improve over time, supporting the hypothesis of reversible network dysfunction. Although limited by the very small sample size, this study provides the first longitudinal assessment of emergency task-based fMRI in rigorously defined TIA and supports further investigation of acute functional MRI as a potential biomarker of transient cerebral dysfunction.

19
Functional fine-mapping of the 9p21.3 cardiovascular disease locus implicates the lncRNA MIR31HG as an effector transcript in endothelial cells

Zhigulev, A.; Poujade, F.-A.; Gryzunov, N.; Buyan, A.; Li, H.; Bergman, O.; Liu, M.; Pradhananga, S.; Franco-Cereceda, A.; Swoboda, P.; Kulakovskiy, I. V.; Eriksson, P.; Sahlen, P.; Björck, H. M.

2026-10-19 cardiovascular medicine 10.64898/2026.10.15.26365688 medRxiv
Top 3%
0.0%
Show abstract

BACKGROUND: The chromosome 9p21.3 locus is among the strongest genetic risk loci for cardiovascular disease (CVD), yet the regulatory mechanisms underlying this association remain poorly understood. Previous vascular disease studies focused predominantly on the role of this locus in smooth muscle cell (SMC) dysfunction, whereas its potential role in endothelial cells (ECs) remains less well characterized. Here, we sought to identify candidate regulatory variants at 9p21.3, their distal target genes, and effector transcripts that contribute to CVD-related phenotypes in ECs. METHODS: Promoter capture Hi-C was used to map chromatin interactions at 9p21.3 in primary human ascending aortic SMCs (n=6), supplementing the previously obtained ECs (n=16) dataset. To support the regulatory relevance of these interactions, expression quantitative trait locus analysis was performed in 136 vascular biopsies. Variant effects were prioritized in silico using AlphaGenome. The regulatory activity of the prioritized region was validated using CRISPR activation. RESULTS: Chromatin interaction mapping identified a complex regulatory architecture at the 9p21.3 locus involving 19 putative regulatory elements and 15 genes across ECs and SMCs. MIR31HG showed the most recurrent distal promoter connectivity with the 9p21.3 region. Consistent with the chromatin interaction map, expression of MIR31HG transcripts was associated with genetic variation at the 9p21.3 locus. In ECs, the lncRNA MIR31HG, but not miR-31, was responsive to hemodynamic flow. Depletion of MIR31HG in ECs was associated with endothelial activation. Epigenetic tracks and deep learning predictions highlighted an active enhancer element at 9p21.3, which was subsequently validated by CRISPR activation and increased MIR31HG expression, confirming its capacity to regulate MIR31HG over a large genomic distance of approximately 538 kb. CONCLUSIONS: Altogether, these data implicate lncRNA MIR31HG as a likely effector of the 9p21.3 CVD locus, linking the cis-regulatory element and heritable genetic variation in the respective region to endothelial activation through long-range enhancer regulation.

20
From meal text to carbohydrate to postprandial glucose rise: QLoRA fine-tuning of the Qwen3-4B language model and gradient-boosting prediction in type 2 diabetes

Bou Ali, M. N.; Lassoued, N.; Ben Amor, B.; Nasr, S.; Aouididi, M. A.

2026-10-19 endocrinology 10.64898/2026.10.15.26365634 medRxiv
Top 3%
0.0%
Show abstract

Background. In people with type 2 diabetes (T2D), postprandial glucose weighs on glycaemic control, and carbohydrate counting is difficult. Patients can describe their meal but rarely quantify it. Objective. To assess (1) whether a small open large language model (LLM), fine-tuned on public data, estimates the carbohydrate content of a meal described in words, and (2) what this carbohydrate adds to the prediction of the postprandial glucose rise in two public cohorts. Methods. Step 1: the Qwen3-4B LLM was fine-tuned with QLoRA on Nutrition5k dishes and compared with an automatically matched USDA food composition table and with Qwen3-4B and Qwen3-8B used without training, on test dishes (internal control) and on 100 real meals of ShanghaiT2DM patients, whose reference carbohydrate was computed from the recorded quantities. Step 2: the maximum glucose rise between 0 and 120 minutes ({Delta}Gmax) was predicted by personalised gradient boosting (M2), compared with a spline linear regression and with the Chronos-2 foundation model, using only information available at meal start and person-level cross-validation, in ShanghaiT2DM (people with T2D recruited in two Shanghai hospitals; carbohydrate estimated by the LLM) and CGMacros (free-living adults in Santa Barbara, California; carbohydrate entered in the dataset, no text). Step 3: the model was transferred between datasets. 95% confidence intervals (CI) were obtained by cluster BCa bootstrap (2,000 resamples). Results. On the 100 real meals, the carbohydrate mean absolute error (MAE) of the fine-tuned model was 12.2 [9.9, 15.2] g, almost half that of the table (22.6 g; paired difference -10.5 [-16.8, -6.0] g) and nearly a third of that of the same model without fine-tuning (34.3 g), with a bias of -10.3 g; on test dishes it was 2.2 [2.0, 2.5] g. Personalised gradient boosting (M2) reached a correlation between predicted and observed rises of r = 0.63 [0.55, 0.69] in CGMacros (1,286 meals, 45 adults) and 0.49 [0.42, 0.54] in ShanghaiT2DM (2,339 meals, 99 people with T2D), about twice the linear reference (r = 0.32 and 0.23); for a rise above 50 mg/dL, its area under the ROC curve (AUROC) was 0.80 and 0.74, versus 0.64 and 0.68 with pre-meal glucose alone. Adding carbohydrate to pre-meal glucose changed r by 0.095 [0.068, 0.128] in CGMacros and by 0.004 [-0.010, 0.017] in ShanghaiT2DM; difference between datasets: 0.091 [0.060, 0.126]. Applied from one dataset to the other, the model lost correlation ({Delta}r = -0.11 [-0.17, -0.05] towards ShanghaiT2DM and -0.12 [-0.19, -0.04] towards CGMacros). The full "text [-&gt;] LLM [-&gt;] glucose" chain was evaluated in ShanghaiT2DM only. Conclusion. An open 4-billion-parameter LLM, fine-tuned with QLoRA on public data and usable offline, almost halves the error of carbohydrate counting for real meals described in words compared with an automatically matched table, with an underestimation of large meals. Personalised gradient boosting, based on pre-meal glucose and the person's usual response, doubles the correlation of a linear reference for predicting the glucose rise in both cohorts. Carbohydrate improved this prediction in CGMacros but not in ShanghaiT2DM; the two datasets differ in many respects, and the cause of this gap is not established.