Cardiometabolic Risk in Chronic Spinal Cord Injury : A Systematic Review with Meta-Analysis and Temporal and Geographical Trends

Objectives: This systematic review with meta-analysis compared cardiometabolic syndrome (CMS) in adults with chronic (≥1 year) spinal cord injury (SCI) to non-SCI individuals (controls) and athletes, analyzing the effect of specific injury characteristics and exploring temporal and geographical trends. Methods: Ovid Medline, Embase, Cochrane, CINAHL, Scopus, and Web of Science were searched from inception to September 2024. Adults with chronic SCI were included based on observational and baseline data derived from experimental studies. Quality Assessment Criteria for Evaluating Primary Research Papers from a Variety of Fields assessed quality. Weighted means with 95% bootstrapped confidence intervals (CI) were computed for risk stratification. Group differences were assessed using random effects meta-analysis, calculating weighted mean differences with 95% bootstrapped CI. Temporal and geographical trends were evaluated with linear regression based on sample-size-weighted distributions and relevant covariates. Results: Of 31,163 identified records, 471 studies were included (n ≤ 31,782 SCI participants). CMS was present in men with SCI, paraplegia, tetraplegia, and injuries above T6; men with complete SCI (AIS A); and men and women with motor-complete SCI (AIS A–B). Compared to controls, adults with SCI had a lower body mass index (BMI), higher total and visceral fat, and worse lipid and carbohydrate profiles, including increased insulin resistance (IR). Tetraplegia was associated with greater visceral fat, poorer glycemic control, and lower BMI, insulin sensitivity, high-density lipoprotein-cholesterol (HDL-C), and triglycerides than paraplegia. Motor-complete SCI had lower BMI, HDL-C, and fasting glucose than motor-incomplete injuries. Injuries above T6 had lower blood pressure and higher fasting insulin levels than those below T6. Athletes with SCI had a lower BMI, fat mass, and fasting glucose, and higher systolic blood pressure than non-athletes with SCI, but frequently presented with obesity and carbohydrate dysfunction. Temporal analysis revealed increasing obesity trends and improved systolic blood pressure, while other CMS risk factors remained unchanged. We also identified global variations in obesity, lipids, blood pressure, and carbohydrate patterns. Conclusions: With a large sample, we revealed a widespread cardiometabolic burden in chronic SCI, even among athletes. Specifically, obesity, IR, and hypoalphalipoproteinemia worsened with increasing injury severity, alongside rising obesity trends and geographic disparities in risk profiles. These patterns highlight the evolution of what was deemed an epidemic into a global cardiometabolic pandemic.