A prospective study on association between 2 years change of waist circumference and incident hypertension in Han Chinese

Background: Few prospective studies on association between waist circumference and hypertension have taken account of the dynamic change of WC, which caused by lifestyle modification. Methods: After a baseline investigation, we conducted the first and the second follow-up assessments for subjects after 2 and 5 years, respectively. The difference value (D-value, the value at the first follow-up minus the value at baseline) in WC was calculated to evaluate 2 years change of WC. The association between 2 years change of WC and incident hypertension was analyzed by using Cox proportional hazards regression model. Results: Among 2778 participants free of hypertension at baseline and the first follow-up, 660 (23.8%) subjects developed hypertension over a period of 5 years (between the first and the second follow-up assessments). In both genders, the incidence density and HRs of hypertension were all increased with WC D-value regardless of their abdominal obesity status at baseline. Compared with participants who were non-abdominal obese both at baseline and first follow up, hypertension risk was higher in subjects who were abdominal obese both at baseline and the first follow-up, and in subjects who were non-abdominal obese at baseline but with abdominal obesity at the first follow up. Conclusions: WC dynamic change was associated with incident hypertension, and more WC reduction was associated with more hypertension risk decrease. (C) 2012 Elsevier Ireland Ltd. All rights reserved.