Discordant risk: overweight and cardiometabolic risk in Chinese adults

Abstract

Objective: Recent US work identified "metabolically healthy overweight" and "metabolically at risk normal weight" individuals. Less is known for modernizing countries with recent increased obesity.

Design and methods: Fasting blood samples, anthropometry and blood pressure from 8,233 adults aged 18-98 in the 2009 nationwide China Health and Nutrition Survey, were used to determine prevalence of overweight (Asian cut point, BMI ≥ 23 kg/m(2) ) and five risk factors (prediabetes/diabetes (hemoglobin A1c ≥ 5.7%) inflammation (high-sensitivity C-reactive protein (hsCRP) ≥ 3 mg/l), prehypertension/hypertension (Systolic blood pressure/diastolic blood pressure ≥ 130/85 mm Hg), high triglycerides (≥ 150 mg/dl), low high-density lipoprotein cholesterol (<40 (men)/ <50 mg/dl (women)). Sex-stratified, logistic, and multinomial logistic regression models estimated concurrent obesity and cardiometabolic risk, with and without abdominal obesity, adjusting for age, smoking, alcohol consumption, physical activity, urbanicity, and income.

Results: Irrespective of urbanicity, 78.3% of the sample had ≥ 1 elevated cardiometabolic risk factor (normal weight: 33.2% had ≥ 1 elevated risk factor; overweight: 5.7% had none). At the age of 18-30 years, 47.4% had no elevated risk factors, which dropped to 6% by the age 70, largely due to age-related increase in hypertension risk (18-30 years: 11%; >70 years: 73%). Abdominal obesity was highly predictive of metabolic risk, irrespective of overweight (e.g., "metabolically at risk overweight" relative to "metabolically healthy normal weight" (men: relative risk ratio (RRR) = 39.06; 95% confidence interval (CI): 23.47, 65.00; women: RRR = 22.26; 95% CI: 17.49, 28.33)).

Conclusion: A large proportion of Chinese adults have metabolic abnormalities. High hypertension risk with age, underlies the low prevalence of metabolically healthy overweight. Screening for cardiometabolic-related outcomes dependent upon overweight will likely miss a large portion of the Chinese at risk population.

Figure 1. Concurrent Overweighta and Cardiometabolic Riskb, Total Population and Across Urbanicity

^aOverweight defined using the BMI≥23 kg/m² cutpoint(17) ^bCardiometabolic Risk, defined as one or more of the following risk factors: dysglycemia (HbA1c≥5.7%) inflammation (hsCRP ≥3 mg/L), pre-hypertension/hypertension (SBP/DBP≥130/85 mmHg), high triglycerides (≥150 mg/dL), low high-density lipoprotein cholesterol (<40 mg/dL, men; <50 mg/dL, women). NOTE: MH NW = Metabolically Healthy, Normal Weight MH OW = Metabolically Healthy, Overweight MAR NW = Metabolically at Risk, Normal Weight MAR OW =Metabolically at Risk, Overweight