Study casts doubt on thiazide insulin action effects
medwireNews: Treatment with an ACE inhibitor in combination with a low-dose thiazide diuretic has no different effect on insulin action to that of low-dose thiazide diureticmonotherapy in mildly hypertensive, overweight patients, results of a small study show.
A team found no difference in glucose disposal or endogenous glucose production in non-diabetic hypertensive patients who were treated for 12 weeks with an ACE inhibitor and a thiazide diuretic compared with those who received the thiazide diuretic alone.
The authors say their study refutes the concern that thiazide diuretics have "detrimental effects on glucose metabolism."
"Based on our results, physicians should be encouraged to continue to prescribe these effective drugs," write Patrick Bell (Royal Victoria Hospital, Belfast, UK) and team in Hypertension.
The study included 12 patients (mean age, 59 years; mean body mass index, 29.2 kg/m2) who had well controlled essential hypertension on no more than two antihypertensive agents at baseline.
After an initial 6-week run-in phase, followed by 12 weeks on-treatment, there were no differences in blood pressure, fasting glucose or insulin, glycated hemoglobin, or lipid levels between patients who received the combination of an ACE inhibitor plus low-dose thiazide and those who received the low-dose thiazide diuretic only.
Furthermore, results from euglycemic hyperinsulinemic clamp measurements showed that exogenous glucose infusion rates were identical between the groups. Similarly, there were no differences in endogenous glucose production in the basal state, nor in the degree of suppression in endogenous glucose production during hyperinsulinemia.
Adam Whaley-Connell and James Sowers (University of Missouri, Columbia, USA) nonetheless point out in a related editorial that "use of thiazides has been clearly linked to new-onset diabetes mellitus in clinical trials and impairments in insulin sensitivity, especially in those at increased risk, such as overweight, hypertensive individuals."
They note that it is possible thiazides may influence insulin sensitivity by alternative mechanisms to glucose disposal, such as through β-cell insulin resistance.
While they concede that the study findings "should help guide clinicians in choosing an antihypertensive regimen in at-risk populations," they add: "That being said, previous work results from the current group and others would continue to suggest the use of higher dose thiazide-type diuretics alone or in combination should be avoided in these same at-risk populations."
medwireNews (www.medwirenews.com) is an independent clinical news service provided by Springer Healthcare Limited. © Springer Healthcare Ltd; 2013
By Caroline Price, Senior medwireNews Reporter