Does aspirin attenuate the beneficial effect of ACE inhibitors in elderly people with heart failure?
BACKGROUND
Several studies have raised concerns over a possible reduction in the beneficial effects of ACE inhibitors on mortality in people also taking aspirin (acetylsalicylic acid).


OBJECTIVE
We performed this study to determine whether there is a reduction in the beneficial effects of ACE inhibitors on mortality in elderly people with heart failure also taking aspirin.


METHODS
822 patients discharged from hospital wards with a diagnosis of heart failure participated in the GIFA (Italian Group of Pharmacoepidemiology in the Elderly) study.


METHODS
We analysed the characteristics of the participants according to the type of therapy prescribed (no ACE inhibitor/no aspirin, ACE inhibitor/no aspirin, no ACE inhibitor/aspirin and ACE inhibitor/aspirin). We calculated the hazard ratios (HRs) for dying associated with each of these treatments, and calculated the synergy index to identify any negative interaction between ACE inhibitor and aspirin.


RESULTS
The mean age of study participants was 79 +/- 7.3 (SD) years. Of the 629 (76.5%) patients discharged on ACE inhibitor and/or aspirin therapy, 31.0% were taking both drugs. Compared with no therapy with ACE inhibitor or aspirin, the HR for death was 0.65 (95% CI 0.31, 1.36) for aspirin users, 0.45 (95% CI 0.27, 0.74) for ACE inhibitor users and 0.37 (95% CI 0.19, 0.70) for ACE inhibitor/aspirin users. The synergy index was 0.98 (95% CI 0.34, 2.80), suggesting no interaction between the drugs.


CONCLUSIONS
Our data do not support the existence of a negative interaction between ACE inhibitors and aspirin in elderly patients with heart failure.
Pedone
Claudio
C
Cattedra di Geriatria, Universita 'Campus Biomedico', Rome, Italy. c.pedone@unicampus.it
Cecchi
Enrica
E
Matucci
Rosanna
R
Pahor
Marco
M
Carosella
Luciana
L
Bernabei
Roberto
R
Mugelli
Alessandro
A
D000368:Aged; D000369:Aged, 80 and over; D000806:Angiotensin-Converting Enzyme Inhibitors / Q000627:therapeutic use*; D001241:Aspirin / Q000627:therapeutic use*; D016861:Cyclooxygenase Inhibitors / Q000627:therapeutic use; D004347:Drug Interactions; D005260:Female; D005500:Follow-Up Studies; D006333:Heart Failure / Q000188:drug therapy* / Q000401:mortality*; D006801:Humans; D008297:Male; D016016:Proportional Hazards Models; D015996:Survival Rate
D000806:Angiotensin-Converting Enzyme Inhibitors; D016861:Cyclooxygenase Inhibitors; D001241:Aspirin