The Double Burden of Normal Weight Obesity (NWO) and Normal Weight Central Obesity (NWCO) on Hypertension Risk: A Cross-sectional Study

Abstract

Abstract Background Normal weight obesity (NWO) and normal weight central obesity (NWCO) have emerged as risk factors for cardiovascular disease. However, the association between the prevalence of these two conditions and hypertension risk has not been well studied, especially in Asian populations. Methods In this community-based cross-sectional study, we assessed body composition and blood pressure in 1000 adults aged > 20–65 years. NWO was defined as a normal body mass index (BMI 18.5–22.9 kg/m2) plus a high body fat percentage (> 20.6% in men, > 33.4% in women). NWCO was defined on the basis of a normal BMI plus high waist circumference (≥ 90 cm in men, ≥ 80 cm in women). Hypertension and prehypertension were defined as per the JNC 7 guidelines. Results The prevalence of NWO was 38%, affecting 228 of 600 normal-weight individuals. The prevalence of normal weight central obesity was 32% (192 of 600 participants with a normal BMI NWO and NWCO had drastically elevated hypertension odds of 3.2 (95% CI 2.1–4.7) and 3.5 (95% CI 2.3–5.2) times versus metabolically healthy normal weight people, respectively, independent of confounders). The odds for prehypertension were also greater for NWO (OR 1.7, 95% CI 1.1–2.6) and NWCO (OR 2.0, 95% CI 1.3–3.2). Conclusion A high proportion of normal-weight adults in this population have elevated cardiovascular risk based on excess body fat and abdominal adiposity. Assessing body composition would better identify at-risk individuals missed by BMI categorization alone. Reducing the double burden of NWO and NWCO may help lower the prevalence of hypertension in the population.