Basal Metabolic Requirements, Biomarkers of Cardiometabolic Health, and Anthropometric Measures of Obesity in Women and Men With Restricted Growth Conditions

Population-specific thresholds have not been defined for the levels of adiposity and systemic biomarkers that predict chronic health risks in people with restricted growth conditions. Here, anthropometric measures of adiposity, basal metabolic requirements, and fasted blood samples were obtained from adults with restricted growth (age 41 ± 14 years, height 1.30 ± 0.10 m, body mass 60.5 ± 18.3 kg, female: male n = 24:13, achondroplasia n = 26; mean ± SD). Basal metabolic rate was 6529 ± 1703 kJ·d⁻¹ and total mass-normalized energy requirements were higher for females versus males. Plasma concentrations of glucose (5.55 ± 0.73 mmol·L⁻¹), insulin (36.4 ± 19.9 pmol·L⁻¹) and lipids (triacylglycerol 0.84 ± 0.37 mmol·L⁻¹; total cholesterol 4.54 ± 0.85 mmol·L⁻¹; high-density lipoprotein cholesterol 1.41 ± 0.31 mmol·L⁻¹; low-density lipoprotein cholesterol 2.73 ± 0.69 mmol·L⁻¹) were mostly within healthy clinical reference ranges. Sagittal abdominal diameter was positively correlated with plasma glucose and leptin concentrations (r = 0.85; 95% CI: 0.61, 0.95; p < 0.0001, and r = 0.85; 95% CI: 0.61, 0.95; p < 0.0001, respectively). Mean ± SD body mass index (BMI) was 36.1 ± 11.0 kg·m⁻². However, we found that body mass scaled to height by the power of 1.4 (95% CI: 0.2, 2.6) rather than 2 associated with conventional BMI. Conventional biomarkers of cardiometabolic health are not substantially elevated in these individuals with restricted growth despite the classification of obesity using height-dependent references (e.g., traditional BMI).