Objective: To determine the association of alcohol consumption with years-long blood pressure (BP) change, as well as baseline BP, adjusted for potential confounders.
Design: A prospective cohort study.
Setting: A metal-products factory in Toyama, Japan.
Participants: A total of 3900 men aged 20-59 years.
Main outcome measures: BP was measured annually for 7 years after the baseline examination. The generalized estimating equation method was used to analyze the relationship of alcohol consumption to baseline BP and average annual BP change, adjusting for age, yearly weight, work-related factors, and lifestyle factors, including the frequency of intake of 22 food groups.
Results: The baseline systolic BP after multivariate adjustment was 3.9 and 5.0 mmHg higher in drinkers consuming 200-299 and > or = 300 g alcohol/week, respectively, than in non-drinkers (P < 0.001). The annual increase in systolic BP was 0.44 mmHg greater in drinkers consuming > or = 300 g/week than in non-drinkers after adjustment for age and weight change (P < 0.001), where the increase over 7 years was estimated to be 3.08 mmHg greater. Even after being adjusted for the frequency of intake of 22 food groups, drinkers consuming > or = 300 g/week showed a 0.33 mmHg greater annual increase in systolic BP than non-drinkers (P = 0.022). Baseline diastolic BP was significantly associated with alcohol consumption, but annual BP change was not.
Conclusions: An alcohol intake > or = 300 g/week was associated with significantly greater annual BP increase, and baseline BP was significantly higher in drinkers consuming > or = 200 g/week. It is necessary to limit alcohol intake to less than 200 g/week to prevent hypertension.