The safety of spironolactone treatment in patients with heart failure.
BACKGROUND
Spironolactone is increasingly being used in the treatment of heart failure. However, it has been associated with cases of hyperkalaemia. The common use of angiotensin-converting enzyme (ACE) inhibitors and angiotensin-2 receptor (AT2) antagonists in heart failure increases the risk of hyperkalaemia.


OBJECTIVE
To identify the risk of spironolactone withdrawal, hyperkalaemia and severe hyperkalaemia in patients prescribed spironolactone together with either an ACE inhibitor or an AT2 antagonist.


METHODS
Retrospective identification and analysis of patients co-prescribed an ACE inhibitor or an AT2 antagonist with spironolactone. Patients' records were linked to their biochemical results and the doses of spironolactone, ACE inhibitor and AT2 antagonists received by them.


RESULTS
We found that a higher proportion of patients in our cohort stopped taking spironolactone compared with the Randomised Aldactone Evaluation Study and a higher proportion developed hyperkalaemia, a predicted adverse effect of spironolactone combination with an ACE inhibitor or an AT2 antagonist. Patients with diabetes mellitus and those with a haematocrit below 0.36, were more likely to develop hyperkalaemia than those without these traits.


CONCLUSIONS
Spironolactone is a common cause of hyperkalaemia when used in combination with either an ACE inhibitor or an AT2 antagonist. This reinforces the need for care when extrapolating the results of clinical trials to daily clinical practice.
Anton
C
C
West Midlands Centre for Adverse Drug Reaction Reporting and Cardiology Department, City Hospital, Birmingham, UK.
Cox
A R
AR
Watson
R D S
RD
Ferner
R E
RE
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D057912:Angiotensin II Type 2 Receptor Blockers; D000806:Angiotensin-Converting Enzyme Inhibitors / Q000009:adverse effects / Q000627:therapeutic use; D004359:Drug Therapy, Combination; D005260:Female; D006333:Heart Failure / Q000188:drug therapy* / Q000401:mortality; D006784:Hospitals, Teaching; D006801:Humans; D006947:Hyperkalemia / Q000139:chemically induced*; D008297:Male; D008875:Middle Aged; D000451:Mineralocorticoid Receptor Antagonists / Q000009:adverse effects* / Q000627:therapeutic use; D012189:Retrospective Studies; D012307:Risk Factors; D013148:Spironolactone / Q000009:adverse effects* / Q000627:therapeutic use; D015996:Survival Rate
D057912:Angiotensin II Type 2 Receptor Blockers; D000806:Angiotensin-Converting Enzyme Inhibitors; D000451:Mineralocorticoid Receptor Antagonists; D013148:Spironolactone