Spironolactone for the treatment of isolated systolic hypertension

To the Editor: Isolated systolic hypertension (ISH) is associated with a blunted nocturnal blood pressure dip and left ventricular hypertrophy.1 Treatment of ISH is effective in the prevention of congestive heart failure and cerebrovascular accidents; however, control of ISH usually requires combination therapy that is often difficult, with only 50% of patients controlled.2–5 Prior randomized, controlled ISH studies have used protocols based on diuretics, dihydropyridine calcium channel blockers, and angiotensin-converting enzyme (ACE) inhibitors that have decreased systolic blood pressure (SBP) by 23 to 27 mmHg in the treatment groups. Spironolactone has been added for the treatment of resistant ISH in our general semi-rural, internal medicine practice for the past several years. Escribe, (Lillecorp, Albany, NY), our electronic record company, provided a list of all patients in the practice that had spironolactone on their medication list. A retrospective chart review of these patients was performed and only data from patients that were receiving spironolactone for hypertension treatment was collected. Office blood pressures (BPs) were averaged from 1 to 3 visits before treatment with spironolactone (pre-spiro) and after the addition of spironolactone (post-spiro). The office BP reflected the usual clinical practice of BP measurement; however, it was not performed in a standard manner. Forty-eight patients were identified, with an average age of 71.6 ± 10.1 years and a pre-spiro BP of 157.7 ± 16.4/74.5 ± 11.8 mm Hg. Post-spiro BP was 141.7 ± 19.5/70.6 ± 12.6 mm Hg (P < .05 for both SBP and diastolic BP [DBP]). The addition of spironolactone decreased BP by 15.9/3.8 mm Hg (P < .05). This group was subdivided into spironolactone responders (≥10 mm Hg decrease in SBP) and nonresponders (<10 mm Hg decrease in SBP). There were 33 responders (69%) and 15 nonresponders (31%), with similar average ages in both groups. The addition of spironolactone decreased BP by 25.3/8.1 mm Hg for the responders and by 0.6/−0.1 mm Hg for the nonresponders (P < .05 for both SBP and DBP). There were no significant differences (P > .05) between responders and nonresponders for the number of drugs before or after the addition of spironolactone, number of visits before or after spironolactone, or number of patients receiving ACE inhibitors, angiotensin receptor blockers, calcium channel blockers, β-blockers, or other drug categories. There are many limitations to this retrospective chart review; however, the significant reduction in SBP was similar to the 13.4 mm Hg decrease with eplerenone—a selective aldosterone blocker—combined with an ACE inhibitor or the 16.0 mm Hg decrease seen with eplerenone combined with an angiotensin receptor blocker in a younger population.6 A randomized, controlled trial with spironolactone or eplerenone should be considered for the efficacy of ISH treatment.