Differences in rates of uptake of NICE clinical guidelines between Type 1 diabetes mellitus (T1DM) and Type 2 diabetes mellitus (T2DM) as evidenced by National Diabetes Audit of England and Wales

OBJECTIVESTo investigate whether there were important differences in uptake of NICE clinical guidelines according to diabetes mellitus type in England and Wales from 2013 to 2018, test the hypothesis that guidelines are more successfully implemented with T2DM than T1DM, and explore possible explanations for differences. DESIGNRetrospective cross-sectional analyses of aggregated patient level data from the National Diabetes Audit (NDA) dataset owned by NHS Digital and commissioned by Healthcare Quality Improvement Partnership. SETTINGDiabetes specialist services, primary care (GP surgeries submitting NDA data) across England and Wales. PARTICIPANTS1 739 175 patients with diabetes aged [&ge;]20 in England and Wales in 2013-14, 1 871 320 individual patients in 2014-15, 2 688 106 individual patients in 2015-16, 3 095 275 individual patients in 2016-17, and 3 357 055 individual patients in 2017-18. INTERVENTIONSRecommended care for diabetes mellitus as outlined in relevant NICE guidelines and delivered by either specialist clinicians or GPs. MAIN OUTCOME MEASURESThe recorded attainment of NICE treatment targets: HbA1c levels =<7.5% (58.5 mmol/mol), blood pressure <140/80mmHg, blood cholesterol <5mmol/l; and clinical processes: at least annual monitoring of HbA1c, blood pressure, cholesterol, albumin:creatinine ratio, smoking status, Body Mass Index. RESULTSAnnual collections (2013-14, 2014-15, 2015-16, 2016-17 and 2017-18) were individually analysed, testing associations between diabetes type and attainment of clinical targets or processes using a multivariable logistic regression model, adjusted for age and sex. Increased odds of meeting clinical targets if patients had T2DM compared with T1DM was consistent across the five years, except for cholesterol levels <5mmol/l where T2DM patients had lower odds (all associations p<.0001). Greatest differences in all five years between T1DM and T2DM was observed with patients meeting the HbA1c=<7.5% target, the largest being in 2015-16 (Odds Ratio 3.43, 95% confidence interval 3.39 to 3.47). CONCLUSIONSThe differences between T1DM and T2DM in HbA1c target attainment is key and potentially reflects challenges of managing T1DM with insulin but suggests a point of focus for that patient population. Other important elements for consideration could be specific setting for delivery (primary care versus secondary care) and duration of illness. O_TEXTBOXWHAT IS ALREADY KNOWN ON THIS TOPICNHS Digital publishes reports on the NDA every year, however much of this is descriptive rather than analytical. Very few published studies have explored NDA data and none have particularly compared clinical outcomes of T1DM and T2DM. WHAT THIS STUDY ADDSDifferences between age structures of T1DM and T2DM patient groups are adjusted and success in meeting NICE clinical processes and treatment targets are compared. This study highlights the different challenges faced by these different groups and conditions and raises questions about the suitability of applying identical targets to the diabetes subtypes given aetiological, clinical and therapeutic differences. C_TEXTBOX