Prevalence and Risk Factors of Hypertension without Controlled Drug Treatment in Three Regions: A Study of Japanese Rural Populations / Journal of Rural Medicine

ABSTRACT

Background: Little information has been collected on the prevalence of hypertension in different rural parts of Japan, using similar methods for sample selection and based on similar diagnostic criteria, and epidemiological studies are urgently needed in each Japanese rural county to determine the baseline against which future trends in risk factor levels can be assessed in order to be able to plan appropriate preventive strategies. Objective: To study the prevalence and its relationship to risk factors of hypertension without controlled drug treatment in rural populations. Materials and Methods: Three cross-sectional surveys were conducted in the Akita (north), Gifu (middle) and Fukuoka (south) regions during 2004-2005 using study subjects (n=1778) aged 40-79 years who participated in a health check-up program. Blood pressure was measured by a trained nurse. Information concerning their history of hypertension and lifestyle was obtained by self-administered questionnaires. Results: When comparing the three regions, the prevalence of hypertension (≥140/90 mmHg) without controlled drug treatment demonstrated a significant difference among males (16.8%, 22.1% and 12.7% in Akita, Gifu and Fukuoka, respectively; p<0.05). However, no significant difference was seen among females (14.4%, 16.0% and 16.5% in Akita, Gifu and Fukuoka, respectively). According to a multivariate logistic regression analysis for these two groups in each of the three regions, the odds ratio (OR) showed that obesity (body mass index≥25 kg/m2) was strongly associated with the Hypertensive (-) group among females in two regions (ORs of 2.32 for both Akita and Fukuoka). Physical inactivity (average daily physical activity energy expenditure<300 kcal), alcohol drinking (alcohol intake≥44 g/day and/or frequency of drinking≥5 days/week), cigarette smoking (Brinkman index≥400) and a stressful lifestyle were not significantly associated with the Hypertensive (-) group among these rural populations. Conclusions: Therefore, hypertension in females in rural Japan may be controlled by a reduction in body weight.