Hypertension Treatment Patterns in American Indians: the Strong Heart Study

Pharmacologic treatment patterns for hypertensive American Indians from 13 communities in Arizona, Oklahoma, South Dakota, and North Dakota were assessed. Participants (2254 women and 1384 men, aged 48 to 79 years) completed a clinical examination between July 1993 and December 1995. The mean of two blood pressure (BP) measurements and detailed medication histories were obtained. The observed prevalence of hypertension was 46.7% (n=1698). In participants taking antihypertensive medications (n=1114), four principal drug classes were evaluated: diuretics, calcium channel blocking agents, beta-blocking agents, and angiotensin-converting enzyme (ACE) inhibitors. Among treated hypertensive participants, 71.4%, 24.6%, and 4.0% received one, two, and three medications, respectively. Among single drug regimens, ACE inhibitors (n=340) were used most often (49.4%), with calcium channel blocking agents and diuretics accounting for 24.2% and 19.9%, respectively. Although multiple drug class therapies varied, the combination of a diuretic and ACE inhibitor (n=120) accounted for 47.4% of dual therapy use. Hypertension control (SBP < 140 mm Hg, DBP < 90 mm Hg) rates were highest for those on dual therapies (65.4%), followed by participants on single (53.8%) and triple (43.6%) therapies. Among monotherapies, diuretics exhibited the best overall hypertension control rate in both diabetics (63.0%) and nondiabetics (68.0%), versus 47% to 61% for other remaining agents. The frequent use of ACE inhibitors, used singly or in combination, reflects the high prevalence of diabetes among American Indians. ACE inhibitors, combined with diuretics, were particularly useful in achieving BP control in this population.