A systematic review of associations between risk factors during the first 1000 days of life and cardiometabolic outcomes later in childhood

ImportanceChildhood obesity increases cardiometabolic risk during childhood among individuals aged 2-18 years. These cardiometabolic outcomes include glucose intolerance, dyslipidemia, hypertension, metabolic syndrome, and type 2 diabetes (T2D). In the current state of research, a comprehensive review identifying all early-life exposures and risk factors that could predict cardiometabolic risk in children is lacking. ObjectiveTo identify and evaluate the predictive early-life risk factors during the first 1,000 days of life, including preconception, pregnancy and birth, and early infancy periods for cardiometabolic risk outcomes in childhood. Evidence reviewThe present systematic review of existing literature was conducted to revise and search selected electronic databases (Medline, EMBASE, WEB OF SCIENCE, SCOPUS, and Cochrane CENTRAL) for longitudinal studies published between the databases inception and August 17, 2022. This systematic review protocol was registered to PROSPERO, CRD42022355152, and following the PRISMA guidelines. We selected articles that studied the risk factors in mothers, fathers and infants, from preconception to infancy, for childhood cardiometabolic outcomes between 2 and 18 years. FindingsIn 68 studies, we identified 229 associations between exposures and childhood cardiometabolic outcomes namely glucose intolerance, dyslipidemia, hypertension, metabolic syndrome, and T2D. The majority of associations (n=162) were positively associated with cardiometabolic risk factors. Pregnancy and birth risk factors were the categories with the most reported associations (86%). Among them, the most frequently assessed characteristics were birth anthropometrics (n=75), sociodemographics data (n=47), and pregnancy complications factors (n=34). However, we only identified few risk factors during preconception. In infancy period, breastfeeding (n=16) and infant anthropometrics (n=15) were consistently associated with cardiometabolic outcomes. In all periods, the most studied associations were identified for hypertension and metabolic syndrome. Conclusions and relevanceBirth anthropometrics, sociodemographics, and pregnancy complication factors were the most frequently reported predictive factors associated with a higher risk for cardiometabolic outcomes in children, particularly hypertension and metabolic syndrome. These results of this study are useful for predicting the risk for childhood cardiometabolic outcomes and for the modifiable factors. They also may facilitate the design of approaches aimed at the alteration of several behaviours from birth to infancy, encompassing both the maternal and paternal influences, as well as the preconception to infancy transition period. Future studies evaluating early-life risk factors with scarce scientific evidence, such as paternal and preconception factors, are urgently needed. Key pointsO_ST_ABSQuestionC_ST_ABSWhat is the existing evidence of early-life risk factors during the first 1000 days of life that are associated with cardiometabolic dysfunction between 2 and 18 years? FindingsBirth anthropometrics, pregnancy complications, sociodemographics and lifestyle factors are the most frequently reported associated exposures with hypertension and metabolic syndrome in children. MeaningIdentifying early-life risk factors and changing behavior patterns throughout preconception and infancy can contribute to prevent metabolic diseases later in childhood.