Family history of hypertension and blood pressure in a screened cohort

We sought to determine whether a family history of hypertension is quantita tively associated with the prevalence of hypertension and blood pressure in a screened cohort, Clinical data and family (parents and siblings) histori es regarding hypertension were collected from 9,914 individuals (probands) who were interviewed and examined during a one-day clinic by the Okinawa Ge neral Health Maintenance Association in 1997. We used logistic analysis to calculate odds ratios with adjustments for age, sex, body mass index, total cholesterol, presence of diabetes mellitus, alcohol use, cigarette smoking , and status of physical exercise. The age- and sex-adjusted hypertension p revalences in probands were 29.0% for those with 1 family member with a his tory of hypertension (n=2,112), 37.6% for those with 2 hypertensive family members (n=374), and 47.3% for those with 3 or more hypertensive family mem bers (n=68). In contrast, only 16.4% of probands who reported no family his tory of hypertension (n=7,360) were hypertensive themselves. The trend of t he prevalence according to the number of family members with a history of h ypertension was significantly positive (p=0.003), The adjusted odds ratios (95% confidence interval) of hypertension were 2.74 (2.43-3.10) for 1 membe r, 4.62 (3.62-5.90) for 2 members, and 6.04 (3.51-10.4) for 3 or more membe rs with a history of hypertension. In patients without antihypertensive med ication (n=9,009), systolic/diastolic blood pressure(mean+/-SD) was 121+/-1 7/75+/-11 for 1 member, 124+/-18/77+/-12 for 2 members, and 127+/-17/78+/-1 1 for 3 or more members with a history of hypertension. In contrast, the me an systolic/diastolic blood pressure of probands who reported no family his tory of hypertension (n=7,360) was 119+/-15/74+/-10 mmHg, which was signifi cantly (p<0.05) lower than that of any of the groups with hypertensive fami ly members. In conclusion, an increase in the number of family members with hypertension was associated with an increasing prevalence of hypertension and blood pressure in the probands, independent of conventional risk factor s for hypertension, Family members of hypertensive subjects may need to be treated in primary prevention efforts related to hypertension.