Daily life activity and the risk of developing hypertension in middle-aged Japanese men.

BACKGROUND: Although previous studies suggest that physical activity may reduce the risk of hypertension, the role of daily life activity in the development of hypertension remains unclear.
METHODS: The study population included 2548 Japanese male office workers aged 35 to 59 years, who were without hypertension (systolic blood pressure [SBP] <140 mm Hg, diastolic blood pressure [DBP] <90 mm Hg, and no medication for hypertension) and had no history of cardiovascular disease. Daily life energy expenditure was estimated by a 1-day activity record during an ordinary weekday at study entry. Blood pressures were measured at periodic annual health examinations over 7 successive years.
RESULTS: After controlling for potential predictors of hypertension (age, family history of hypertension, alcohol consumption, cigarette smoking, regular physical exercise at entry, and change in body mass index during the follow-up period), mean SBP and DBP in each follow-up year decreased as daily life energy expenditure increased. With additional adjustment for SBP at entry, the relative risk of hypertension (SBP > or =140 mm Hg and/or DBP > or =90 mm Hg or medication for hypertension) across quartiles of daily life energy expenditure (lowest to highest) were 1.00, 0.84, 0.75, and 0.54 (P<.001 for trend). Analyses by presence or absence of a risk factor demonstrated that the risk of hypertension was inversely related to daily life energy expenditure in men at either low or high risk of hypertension. Daily life energy expenditure was also associated with reduced risk of hypertension for subjects in all 3 categories of normotension: low normal, normal, and high normal.
CONCLUSIONS: Increased daily life activity is effective for the prevention of hypertension, and this benefit applies to men at either low or high risk of hypertension.