Neck Circumference Is Independently Associated with Cardiometabolic Risk Factors: Cross-Sectional Analysis from ELSA-Brasil

Background: Neck circumference (NC) is a simple anthropometric measurement that may be linked with cardiometabolic risk factors. We analyzed the association between NC and a range of cardiometabolic risk factors. Methods: In a cross-sectional and sex-specific analysis of the ELSA-Brasil study (15,105 civil servants aged 35-74 years), we excluded participants with diabetes, taking antihypertensive and/or lipid-lowering drugs. Cardiometabolic risk factors were homeostasis model assessment of insulin resistance (>= 75th percentile), low high-density lipoprotein (HDL; <50 mg/dL for women and <40 mg/dL for men), high triglycerides >= 150 mg/dL, systolic blood pressure >= 130 mmHg, or diastolic blood pressure >= 85 mmHg. Logistic regression models were built to analyze the association between individual and clustered risk factors and 1-standard deviation (SD) increase in NC after adjustments for age, smoking, alcohol, body mass index, and waist circumference. Results: We analyzed 8726 participants (56.3% women), with a mean age of 49.2 +/- 8.0 years. Mean NC was 38.9 +/- 2.6 cm for men and 33.4 +/- 2.6 cm for women. Fully adjusted odds ratios (ORs) [95% confidence intervals (CIs)] per 1-SD increase in NC in men and women were, respectively, 1.32 (1.16-1.51) and 1.47 (1.31-1.64) for insulin resistance; 1.24 (1.11-1.39) and 1.25 (1.11-1.40) for raised blood pressure; 1.50 (1.33-1.70) and 1.51 (1.33-1.70) for high triglycerides; and 1.22 (0.92-1.61) and 1.54 (1.23-1.86) for low HDL. Fully adjusted ORs (95% CI) of three or more clustered risk factors per 1-SD increase in NC in men and women were 1.54 (1.34-1.79) and 1.71 (1.41-2.06). Conclusion: NC is significantly and independently associated with cardiometabolic risk factors in a well-defined apparently healthy population.