RISK-FACTORS FOR THE DEVELOPMENT OF HYPERTENSION - A 6-YEAR LONGITUDINAL-STUDY OF MIDDLE-AGED JAPANESE MEN

Objective To identify the factors related to the development of hypert ension on the basis of annual health examinations at the workplace. Se tting A cohort of Japanese male office workers who were reexamined for six successive years after their initial examinations in 1990. Subjec ts The study cohort comprised 1089 hypertension-free subjects aged 30- 54 years. Six-year follow-ups were completed for 934 subjects (85.8%) Results An analysis using the Kaplan-Meier method showed that the inci dence of hypertension above the borderline level increased significant ly with increasing age, body mass index, systolic blood pressure, dias tolic blood pressure, total cholesterol level, uric acid level, total protein level, hematocrit level, and alcohol intake, This increase was significant for systolic blood pressure, diastolic blood pressure, an d hematocrit level, The highest cumulative incidences both of hyperten sion above the borderline level and of definite hypertension were obse rved among those with 85-89 mmHg diastolic blood pressure, and the sec ond highest among those with 130-139 mmHg systolic blood pressure, Mul tivariate analysis using the Cox proportional hazards model indicated that age, systolic blood pressure, diastolic blood pressure, and alcoh ol intake were independent factors associated with the incidence of hy pertension above the borderline level. Systolic blood pressure, diasto lic blood pressure, and hematocrit level proved to be independently pr edictive of hypertension, and alcohol intake was of borderline signifi cance as a risk factor for hypertension. Conclusion High normal blood pressure is the strongest predictor for the development of hypertensio n among middle-aged Japanese men. In addition, high alcohol intake and high hematocrit level may be contributory factors. (C) 1998 Lippincot t-Raven publishers.