Source
University of Michigan Health System, B2D301 SPC 5008, 1500 East
Medical Center Dr, Ann Arbor, MI 48109-5008, USA.
mdorsch@med.umich.edu
Abstract
There is significant controversy around whether chlorthalidone
(CTD) is superior to hydrochlorothiazide (HCTZ) in hypertension
management. The objective of this analysis was to evaluate the
effects of CTD compared with HCTZ on cardiovascular event (CVE)
rates. We performed a retrospective observational cohort study from
the Multiple Risk Factor Intervention Trial data set from the
National Heart, Lung, and Blood Institute. The Multiple Risk Factor
Intervention Trial was a cardiovascular primary prevention trial
where participants were men 35 to 57 years of age enrolled and
followed beginning in 1973. CVEs were measured yearly, and time to
event was assessed by Cox regression. Systolic blood pressure,
total cholesterol, low-density lipoprotein cholesterol,
high-density lipoprotein cholesterol, triglyceride, potassium,
glucose, and uric acid were measured yearly. The difference between
groups was evaluated by repeated-measures mixed modeling, and each
model was adjusted for predictors of each variable. CVEs were
significantly lower in those on CTD (adjusted hazard ratio: 0.51
[95% CI: 0.43 to 0.61]; P<0.0001) and on HCTZ (adjusted hazard
ratio: 0.65 [95% CI: 0.55 to 0.75]; P<0.0001) compared with
those who took neither drug. When comparing the 2 drugs, CTD had
significantly fewer CVEs compared with HCTZ (P=0.0016). CTD
displayed significantly lower SBP (P<0.0001), lower total
cholesterol (P<0.0001), lower low-density lipoprotein
cholesterol (P=0.0009), lower potassium (P=0.0003), and higher uric
acid (P<0.0001) over time compared with HCTZ. In conclusion,
both HCTZ and CTD reduce CVEs compared with neither drug. When
comparing both drugs, CTD reduces CVEs more than HCTZ, suggesting
that CTD may be the preferred thiazide-type diuretic for
hypertension in patients at high risk of CVEs.
