LONG-TERM EFFICACY AND SAFETY OF SPIRONOLACTONE IN THE TREATMENT OF RESISTANT ARTERIAL HYPERTENSION

Abstract

Objective: Spironolactone is recommended as a fourth line antihypertensive drug by current hypertension guidelines. However, data about its long-term efficacy and safety is limited. Design and method: We prospectively followed 274 patients with resistant arterial hypertension who started treatment with spironolactone between September 2007 and December 2016. Change of office and ambulatory blood pressure (BP) between baseline and the last clinical examination was recorded, as well as the duration of spironolactone use, its dose, changes of other antihypertensive medications, laboratory parameters and the incidence of adverse events. Results: Patients were followed for an average of 35 (± 29) months, the mean daily dose of spironolactone was 27.5 mg. Mean office BP decreased during follow-up from 149/87 mmHg to 136/80 mmHg by a mean 13/7 mmHg (P < 0.001 for both). Mean 24-hour, day-time and night-time ambulatory BP decreased by 12/6 mmHg, 11/6 mmHg and 14/9 mmHg respectively (P < 0.001 for all). Adverse effects occurred in 72 patients (26.3%) and in 61 (22.2%) lead to discontinuation of spironolactone. Adverse events occurred more frequently in patients using angiotensin receptor blockers (hazard ratio – HR 1.65, P = 0.040), in the elderly (HR 1.38, P = 0.007) and patients with higher baseline serum creatinine (HR 1.12, P = 0.035). Conclusions: Our data confirm good long-term antihypertensive efficacy of spironolactone in patients who tolerate it. However, in more than a quarter of patients the use of spironolactone leads to side effects, which usually necessitate its discontinuation.