May 25, 2016Open Access
View Full PaperImpact of Hospitalization for Acute Myocardial Infarction on Adherence to Statins Among Older Adults
Key Result
Hospitalization for AMI increased the likelihood of becoming adherent to statins among previously nonadherent older adults compared with hospitalization for pneumonia (RR 1.70; 95% CI 1.57-1.84).
Study Design
Type
Cohort (n=176,188)
Structured PICO
Does hospitalization for acute myocardial infarction impact subsequent adherence to statins in older adults compared to hospitalization for pneumonia or no hospitalization?
P
Population
176,188 Medicare patients aged ≥65 years taking statins in the year before the index event, including those hospitalized for acute myocardial infarction (n=6,618), hospitalized for pneumonia (n=11,471), and not hospitalized (n=158,099).
I
Intervention
Hospitalization for acute myocardial infarction (AMI)
C
Comparator
Hospitalization for pneumonia or no hospitalization
O
Outcome
Change in statin adherence (proportion of days covered ≥80% vs <80%) in the year after hospitalization compared to the year before
Hospitalization for AMI is associated with improved statin adherence in previously nonadherent older adults, but also an increased risk of nonadherence in previously adherent patients compared to no hospitalization.
Main Result
Effect estimate: RR 1.70 (95% CI 1.57-1.84)
Abstract
BACKGROUND: Little is known about the impact of hospitalization for an acute myocardial infarction (AMI) on subsequent adherence to statins. METHODS AND RESULTS: Using administrative claims from a 5% random sample of Medicare beneficiaries, we identified a cohort of Medicare patients aged ≥65 years, hospitalized from 2007 to 2011, taking statins in the year before AMI hospitalization (n=6618). We then determined the proportion of patients nonadherent to statins (proportion of days covered <80%) in the year before AMI hospitalization who became statin adherent (proportion of days covered ≥80%) in the year after AMI hospitalization. The proportion of statin-adherent patients who became nonadherent was also studied. These proportions were compared with patients hospitalized for pneumonia (n=11 471) and patients not hospitalized (n=158 099) in 2010 and 2011. Among patients nonadherent to statins before AMI hospitalization, 37.7% became adherent after discharge. Patients hospitalized for AMI were more likely to become adherent than patients hospitalized for pneumonia (adjusted relative risk: 1.70; 95% confidence interval, 1.57-1.84) or patients not hospitalized (adjusted relative risk: 1.79; 95% confidence interval, 1.68-1.90). Among patients adherent to statins before AMI hospitalization, 32.6% became nonadherent after discharge. Those hospitalized for AMI were less likely to become nonadherent than those hospitalized for pneumonia (adjusted relative risk: 0.93; 95% confidence interval 0.88-0.98) but more likely to become nonadherent than patients without hospitalizations (adjusted relative risk: 1.41; 95% confidence interval, 1.35-1.48). CONCLUSIONS: Among nonadherent patients, hospitalization for AMI was associated with increased likelihood of becoming adherent to statins compared with hospitalization for pneumonia or no hospitalizations. Among adherent patients, hospitalization for AMI was associated with increased likelihood of becoming nonadherent to statins compared with no hospitalizations.