Calcium channel blockers (CCBs) are an important class of medication useful in the treatment of
hypertension. Several observational studies have suggested an association between CCB
therapy and gastrointestinal (GI)
hemorrhage. Using administrative databases, the authors re-examined in a post-hoc analysis whether the
Antihypertensive and
Lipid-Lowering Treatment to Prevent
Heart Attack Trial (ALLHAT) participants randomized to the CCB
amlodipine had a greater risk of hospitalized GI
bleeding (a prespecified outcome) compared with those randomized to the
diuretic chlorthalidone or the
angiotensin-converting enzyme inhibitor lisinopril. Participants randomized to
chlorthalidone did not have a reduced risk for GI
bleeding hospitalizations compared with participants randomized to
amlodipine (hazard ratio [HR], 1.09; 95% confidence interval [CI], 0.92-1.28). Those randomized to
lisinopril were at increased risk of GI
bleeding compared with those randomized to
chlorthalidone (HR, 1.16; 95% CI, 1.00-1.36). In a post-hoc comparison, participants assigned to
lisinopril therapy had a higher risk of hospitalized GI
hemorrhage (HR, 1.27; 95% CI, 1.06-1.51) vs those assigned to
amlodipine. In-study use of
atenolol prior to first GI
hemorrhage was related to a lower incidence of GI
bleeding (HR, 0.69; 95% CI, 0.57-0.83). Hypertensive patients on
amlodipine do not have an increased risk of GI
bleeding hospitalizations compared with those taking either
chlorthalidone or
lisinopril.