Optimal cutoff values for overweight: using body mass index to predict incidence of hypertension in 18- to 65-year-old Chinese adults.
Studies aimed at identifying BMI cutoffs representing increased diseased risk for Asians are typically based on cross-sectional studies. This study determines an optimal BMI cutoff for overweight that represents elevated incidence of hypertension in Chinese adults with data from the China Health and Nutrition Survey 2000-2004 prospective cohort. Cumulative incidence was calculated by dividing new cases of hypertension over the study period by the total at-risk population, aged 18-65 y, in 2000. Sex-specific receiver operating characteristic curves were used to assess the sensitivity and specificity of BMI as a predictor of hypertension incidence. Four-year cumulative incidences of hypertension (13% for women and 19% for men) were related (P < 0.005) to the increase in BMI. The crude area under the curves (AUC) were 0.62 (95% CI: 0.59-0.65) and 0.62 (95% CI: 0.58-0.65) for men and women, respectively; the age-adjusted AUC were 0.68 (95% CI: 0.65-0.70) and 0.71 (95% CI: 0.68-0.74) for men and women, respectively. A BMI of 23.5 kg/m(2) for women and 22.5 kg/m(2) for men provided the highest sensitivity and specificity (60%). The finding was consistent in different age groups. A BMI level of 25 kg/m(2) provided lower sensitivities (36% for women and 29% for men) with higher specificities (80% for women and 85% for men). Our study supported the hypothesis that the BMI cutoff to define overweight should be lower in Chinese than that in Western populations.
Department of Nutrition, University of North Carolina, Chapel Hill, NC 27516, USA.
T Tuan
TT
Nguyen
Linda S
LS
Adair
Ka
K
He
Barry M
BM
Popkin
D000293:Adolescent; D000328:Adult; D000368:Aged; D044466:Asian People; D015992:Body Mass Index; D002681:China; D005260:Female; D006801:Humans; D006973:Hypertension / Q000209:etiology* / Q000473:pathology; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D050177:Overweight / Q000150:complications* / Q000175:diagnosis* / Q000473:pathology; D016012:Poisson Distribution; D012372:ROC Curve; D012307:Risk Factors; D012680:Sensitivity and Specificity