BACKGROUND: Multiple antihypertensive (AHT) drug classes are also indicated to treat other cardiovascular or non-cardiovascular conditions. Among the most frequent, heart failure (HF) with or without hypertension.
OBJECTIVES: To describe adult patients using AHT medications, focusing on the subgroup of patients with HF.
METHODS: We included patients enrolled in a 17 million persons US claims database, IHIS, on July 1, 2001 with an AHT prescription in 2002. We constructed treatment episodes, of combination or AHT monotherapy. The index treatment episode (ITx) was the first for each regimen and patient. We searched for clinical conditions as proxy for potential label indications 6 months before and after each ITx.
RESULTS: 497475 patients above 17 years used AHT drugs: 1.5 ITxs per patient, 52% women, mean age 56 years. We found potential labeled indication for 83% of ITxs. For monotherapy ITxs with identified indications, 7% were for HF and 79% for hypertension without HF. Over 25% of spironolactone and loop diuretics ITXs were for HF. Most of the HF ITxs (monotherapy or combined) were associated with myocardial infarction (MI) (16%) or hypertension without MI (63%). Diuretics were associated with the highest proportion (over 70%) of concomitant other AHTs, followed by angiotensin II receptor antagonists (68%), calcium channel blockers (64%), spironolactone (62%), angiotensin-converting enzyme inhibitors (56%) and betablockers (50%). 17% of spironolactone Itxs were concomitant with potassium supplements. Among first spironolactone ITxs, 21% were with ACEIs, and 37% with other drugs that could potentially increase the risk of hyperkalemia. For HF patients, 53% were men, mean age 65 years. Most AHTs were in combination therapy (67%). Spironolactone was frequently used with potassium supplements (31% ITxs). 65% of first spironolactone ITxs were with drugs that could potentially increase the risk of hyperkalemia. 80% of patients used doses of spironolactone of less than 75 mg/day.
CONCLUSIONS: Patterns of use of AHT medications differ according to treatment indication and concomitant cardiovascular and non-cardiovascular conditions. Patient populations in this area need to be carefully characterized before initiating epidemiological studies.