Background:
Age is a key determinant of adverse acute events following non-ST-segment elevation myocardial infarction (NSTEMI), but the influence of age on longer-term outcomes in hospital survivors has yet to be explored.
Methods:
Our population included NSTEMI patients aged ≥65 years in the CRUSADE registry who were treated from 2/2003-12/2006 and linked to Medicare claims data for longitudinal follow-up. In-hospital and 1-year mortality rates (among hospital survivors calculated using the Kaplan-Meier method) are shown for nonagenarians and younger elderly-aged groups. Cox proportional hazard modeling was used to adjust for baseline characteristics, discharge medications, and procedures.
Results:
Of 36,711 NSTEMI hospital survivors aged ≥65 years, 58.8% (21586/36711) were 65-79 years old, and 7.6% (2794/36711) were ≥90 years old. Compared with younger elderly adults (ages 65-79), nonagenarians had lower prevalence of diabetes but higher prevalence of congestive heart failure, hypertension, prior stroke, and renal insufficiency (all p<0.0001). The qualifying NSTEMI was more likely to be a first cardiac event (no prior MI, PCI, or CABG) for nonagenarians than for younger elderly adults (59.7% [1669/2794] vs. 51.0% [11002/21586], p<0.0001). Nonagenarians were less likely to receive revascularization (10.3% [289/2794] vs. 56.7% [12238/21586], p<0.0001) and evidence-based discharge medicine, and had high mortality (Table). One-year mortality remained higher for nonagenarians after adjustment (HR 2.15, 95% CI 1.99-2.32, reference age 65-79).
Conclusions:
Nonagenarians with NSTEMI experience 2-fold higher mortality following discharge compared with younger elderly adults, with a mortality rate approaching 50% at 1 year. This hazard persists after adjustment, suggesting the role of unmeasured competing risks in this vulnerable population.
Table.
Discharge medication, in-hospital mortality, and 1-year mortality rates by age category
Discharge medications (%)
65-79 Years
80-84 Years
85-89 Years
≥90 Years
P-value
Aspirin
94.9 19085/21586
93.2 6166/7324
92.6 4118/5007
91.2 2198/2794
<0.001
Clopidogrel
71.5 13677/21586
67.8 4205/7324
64.0 2643/5007
58.2 1220/2794
<0.001
Beta-blocker
92.1 18352/21586
91.7 6119/7324
92.3 4131/5007
92.2 2229/2794
0.942
Statin
80.9 16514/21586
74.2 5018/7324
67.1 2998/5007
56.0 1297/2794
<0.001
ACE inhibitor or ARBs
66.4 13624/21586
65.9 4493/7324
64.2 2891/5007
61.4 1477/2794
<0.001
In-hospital mortality
4.4 996/22582
7.1 560/7784
9.2 509/5516
11.1 348/3141
<0.001
1-year mortality
13.2 2853/21586
23.8 1740/7324
33.5 1676/5007
45.6 1275/2794
–