Discordant risk: overweight and cardiometabolic risk in Chinese adults

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

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.

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)).

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.