To assess the significance of obesity as an etiological cause for essential hypertension, the relation between Body Mass Index (BMI) and blood pressure level was statistically examined from a cross-sectional data of health examinations for male clerical workers aged 40-54.
The conclusions were as follows.
1) Among 640 subjects under analysis, 105 subjects were accompanied by obesity characterized by more than 25.0 of BMI.
2) ‘Rate Ratios’ of the individuals whose BMIs are more than 25.0 to those whose BMIs are less than 25.0 for hypertension (WHO criteria) were 2.77, 1.96 and 2.22 in the three age groups of 40-44yrs, 45-49yrs and 50-54yrs, respectively.
3) ‘Population Attributable Risk Percents’ (PARs) of obesity characterized by more than 25.0 of BMI for hypertension (WHO criteria) were calculated as 21.3±13.6%, 13.2±7.9% and 17.9±7.3% for the three age groups of 40-44yrs, 45-49yrs and 50-54yrs, respectively. Furthermore, the author attempted to estimate the standard PAR level among the whole middle-aged male population by the age-standardization of PAR. If the above three age groups are equally weighed, this age-standardized. PAR is calculated as 17.1%.
4) If the subjects with border-line hypertension (WHO criteria) are also included in hypertensives, the age-standardized PAR is caluculated as 9.5%.
5) These results suggest that about 10-20% of essential hypertension among Japanese middle-aged males could be prevented by the maintenance of desirable weight.
