The Bergen blood pressure study: offspring of two hypertensive parents have significantly higher blood pressures than offspring of one hypertensive and one normotensive parent.

OBJECTIVE

To study blood pressure and antihypertensive drug treatment in subjects with contrasting family histories of hypertension.

SUBJECTS AND METHODS

We grouped 520 offspring examined in 1990 (mean +/- SD age 36 +/- 7 years) according to their parents' blood pressure screened in 1963-1964 as offspring of two normotensive (systolic/diastolic blood pressure < 135/70 mmHg) parents (group 1); offspring of one hypertensive (> or = 145/95 mmHg) and one normotensive (<135/70 mmHg) parent (group 2); and offspring of two hypertensive (> or = 140/90 mmHg) parents (group 3). Offspring blood pressure was measured with a conventional mercury sphygmomanometer by one observer. The mean of the last two of three seated measurements was used for analyses. Drug treatment was determined by interview.

RESULTS

Mean +/- SD blood pressure was lowest in group 1 (121 +/- 12/72 +/- 10 mmHg), intermediate in group 2 (125 +/- 12/76 +/- 9 mmHg) and highest in group 3 (135 +/- 15/85 +/- 11 mmHg), P<0.01 for each. Of the subjects in groups 1, 2 and 3, 1.3, 2.4 and 11.7%, respectively, were taking antihypertensive drugs (P<0.01).

CONCLUSIONS

Screening blood pressure in parents has implications for offspring blood pressure almost 30 years later. Offspring of hypertensive parents have higher blood pressure and are given antihypertensive drugs at higher rates than the offspring of normotensive parents. Also, substantial differences were seen between the offspring of one and of two hypertensive parents. Thus, risk associated with a family history of hypertension varies with the definition of the family history. To obtain maximum contrast in the predisposition to high blood pressure, comparative studies in offspring of hypertensive and normotensive families should be based on blood pressure data from both parents.