Of the 2000 subjects randomly selected from the FilaBavi study base, 1984 (987 men and 997 women) responded to the survey (response rate, 99.2%). The characteristics of the final study sample are described in .
Selected Sociodemographic Characteristics of Study Sample, Bavi District, Vietnam, 2005
Mean blood pressure levels were significantly higher among men than women. The mean SBP was 126.6 (95% CI, 125.4–127.9) among men vs 117.8 (95%, 116.7–118.9) among women, and the mean DBP was 77.0 (95% CI, 76.0–78.0) among men vs 72.5 (95% CI, 71.2–73.8) among women. Among men, mean blood pressure levels increased from 122.2 SBP (95% CI, 120.7–123.7) and 72.8 DBP (95% CI, 71.7–73.9) among those aged 25–34 to 132.2 DBP (95% CI, 129.3–135.2) and 80.4 SBP (95% CI, 78.6–82.3) among those aged 55–64; among women, mean levels increased from 111.4 DBP (95% CI, 110.1–112.7) and 67.7 SBP (95% CI, 66.6–68.8) among those aged 25–34 to 127.1 DBP (95% CI, 124.2–130.0) and 72.5 SBP (95% CI, 71.2–73.8) among those aged 55–64 (data not shown).
Table 2 ( and ) shows the distribution of selected major risk factors for chronic disease by sex and 10-year age group. The overall prevalence of hypertension in Bavi was 18.8% (23.9% among men and 13.7% among women). Of Bavi residents with hypertension, only 35.1% (37.8% of hypertensive men and 32.2% of hypertensive women) were aware of their hypertension, and only 20.1% (17.8% of the men and 24.1% of the women) were being treated for it. Smoking was the main form of tobacco use in Bavi and was very common among men. About 63% of men reported that they currently smoked, and 58% reported doing so daily. The prevalence of smoking among women was only 0.6%. Excess weight was not a major problem in Bavi. The mean BMI was 19.6 (95% CI, 19.3–19.9) among men and 19.9 (95% CI, 19.5–20.3) among women (data not shown), and the prevalence of overweight was only 3.0% among men and 4.0% among women. The most prevalent combination of risk factors was hypertension and smoking (7.2%), followed by hypertension and overweight (1.3%), overweight and current smoking (0.7%), and all three risk factors (0.4%).
Estimated 2005 Prevalence of Selected Risk Factors for Chronic Disease Among Male Bavi District Residents, by Age Group
Estimated 2005 Prevalence of Selected Risk Factors for Chronic Disease Among Female Bavi District Residents, by Age Group, and Among All Residents Aged 25–64
We used multivariate logistic regression models to further analyze the association between selected risk factors for chronic diseases and the sociodemographic variables of age, education level, occupational category, and economic status. The risk factors analyzed were hypertension and overweight (among both men and women) and smoking and the combination of hypertension and smoking (among men only). As shown in , age was significantly associated with hypertension among both men and women and with the combination of hypertension and smoking among men. The prevalence of hypertension increased significantly with age, especially among women (ORs vs women aged 25–34 were 2.7, 5.3, and 11.7, respectively, among women in the next three age categories). Among men, age was also significantly associated with the prevalence of hypertension and smoking combined (ORs vs men aged 25–34 were 2.2, 2.0, and 3.7, respectively, among men in the next three age categories). However, we found no significant association between age and current smoking prevalence among men or between age and overweight among men or women.
Results of a Multivariate Analysis of Selected Risk Factors for Chronic Disease Among Bavi District Residents in 2005, by Sex, Age, Education Level, Occupation, and Economic Status
In our multivariate analysis, we also found that among all men, those in the lowest education category were more likely to have hypertension than those in the highest (OR, 2.5) and that among men who smoked this association was only slightly weaker (OR, 2.1). Among women, occupation was related to hypertension and overweight: those in the "other" occupational category were significantly more likely to be hypertensive (OR, 1.7) and to be overweight (OR, 2.6) than were those who were farmers.
Interestingly, the relationship between economic status and hypertension among men differed substantially from that among women: whereas men in the low economic status group had a significantly lower risk for hypertension than those in the high group (OR, 0.4), women in the low and middle groups both had a significantly higher risk than those in the high group (ORs, 2.6 and 1.6, respectively). Men in the low and middle groups were more likely to currently smoke than were those in the high group (ORs, 2.0 and 1.4, respectively).