Archives IM 11/13- ALLHAT data first made news with the conclusion that older, thiazide type diuretics were just as effective at reducing hypertension related disease as newer types of anti-hypertensives. One result of the study that is less well known is that thiazides appeared to increase the risk of incident diabetes. In the last issue of Archives, the ALLHAT investigators addressed this issue more directly.[Article]
The investigators performed post hoc analyses on the subgroups assigned to Ca-channel blockers, ACE-Is, and thiazides. Patients with known diabetes prior to start of therapy were excluded from analysis, as were those without baseline fasting blood glucose(FG) levels.
The data shows that all subjects had an increase in FG, but the thiazide group had a significantly greater increase in fasting glucose levels than the other groups. In addition, subjects in the thiazide group had significantly greater odds of developing diabetes.
Is this a problem? The investigators state that the increase in DM did not result in a greater rate of adverse events compared to the other groups. Are they trying to sweep the issue under the rug? Or are they postulating that the diabetic state induced by thiazides is less malignant than naturally occuring DM? Adverse events data was only 2 years out – not long enough to show effects from new onset DM. The increased risk may have also been partially washed out by the increase in DM among all groups, and the lack of comparison with placebo. I’m not sure I would dismiss the risk as easily as they suggest – but I guess I dont have to worry about grant money…
With both beta-blockers and thiazides being linked to decreased glucose tolerance, the choice of anti-hypertensives is becoming much more complicated.
