Objective: To describe the distribution of over weight and obesity to discover the level of exposure on risk factors of stroke among people aged 40 and over, in a community-based population.
Methods: From 2003 to 2004, people aged > or = 40 years in a community of Fengxian district in Shanghai were selected by cluster sampling. Out of 11,791 individuals who were selected, 10,565 met the inclusion criteria and responded to the investigation. By face to face interview, a cross-sectional survey was carried out, using a questionnaire for risk factors of stroke. Height, weight and blood pressures were measured and cerebrovascular hemodynamic parameters (CVHP) were checked. Age and gender distribution of over weight and obesity in the population were described. Using 60 year as cut-off point, participants were grouped into three: normal, over weight and obesity by body mass index. Level of stroke risk factor exposure between groups was compared and logistic regression model was used for multiple analyses.
Results: Proportions of over weight and obesity were 28.5 percent and 4.1 percent in male and 26.3 percent and 4.2 percent in female (P = 0.045). Systolic and diastolic blood pressure in over weight group were (132.5 +/- 19.4) mm Hg and (83.9 +/- 10.5) mm Hg (1 mm Hg = 0.133 kPa), which were higher than that in normal weight group and lower than that in obese group (P < 0.05). Exposure rate of heart disease, family history of stroke in < 60 year old group and diabetes in > or = 60 year group increased along with the increase of weight. Exposure rate of hypertension, abnormality of CVHP score in both age groups were also increased with the increase of weight. Data from multiple logistic regression indicated that hypertension, family history of stroke and heart disease, CVHP score below 75 points, sex and age were independent factors of over weight and obese.
Conclusion: The prevalence of over weight or obesity in a community-based population among aged 40 years or over was around 30 percent. The overall exposure rate of stroke risk factors were increasing along with the increase of weight, especially for those in the middle age.