Treatment of hypertension with thiazides: benefit or damage-effect of low- and high-dose thiazide diuretics on arterial elasticity and metabolic parameters in hypertensive patients with and without glucose intolerance.

Thiazide diuretics may cause multiple metabolic abnormalities. The authors investigated the effects of varying doses of hydrochlorothiazide (HCTZ) on arterial elasticity and metabolic parameters in patients with hypertension (HTN), HTN and impaired fasting glucose (HTN+IFG), and HTN and type 2 diabetes mellitus (HTN+DM). The patients received low and high doses of HCTZ. Systolic and diastolic blood pressures declined significantly during the first 3 months in all patients, but no additional decrease was seen following the increase in HCTZ dose. In HTN, large artery elasticity index and small artery elasticity increased during the study. In HTN+IFG, large artery elasticity index increased without improvement in small artery elasticity index. In HTN+DM, both large artery elasticity index and small artery elasticity index did not improve during follow-up. Low-dose HCTZ improves arterial elasticity in hypertensive patients, but this effect is diminished with concomitant DM or IFG. The HCTZ dose increase worsened parameters of glucose metabolism and did not further decrease blood pressure or improve arterial elasticity.