Diabetes in hypertensive women: an effect of antihypertensive drugs or the hypertensive state per se?

A total of 226 women participating in a longitudinal study who were found to be hypertensive (initial values greater than or equal to 160 mmHg for the systolic blood pressure and/or greater than 95 mmHg for the diastolic blood pressure) were followed up with respect to the risk of developing diabetes during a 12-year study period. For each year of follow-up, information on whether each participant was taking antihypertensive drugs or not was collected. As a result there were 1339 'treatment years' and 1449 'non-treatment years' of follow-up. All 16 women who developed diabetes during the follow-up period were taking antihypertensive drugs at the time of onset of their diabetes. A similar observation was made when 145 women within the upper age-specific decentiles of systolic blood pressure were followed up in the same way. These results suggest that in hypertensive subjects antihypertensive drugs rather than the hypertensive state per se predispose to diabetes mellitus.