A new 25-year study finds that mortality after acute myocardial infarction (AMI) and repeat events is falling for all older Americans. But it also highlights the need for more work, especially efforts to eliminate inequalities in health care.
Among the 3.9 million Medicare beneficiaries alive 30 days after an AMI, the 10-year mortality risk was 13.9% lower for patients hospitalized from 2007 to 2009 compared to those hospitalized from 1995 to 1997.
The 10-year risk of recurrent AMI was 22.5% lower from 2007 to 2009, the last 3 years for which 10-year follow-up data was available.
The reductions continued over the study period (1995 to 2019) and were seen across all demographic subgroups, online investigators reported in JAMA Cardiology.
“Survival continues to improve over time, year over year, in the long term, as does the risk of repeat heart attack, so that’s the good news,” said Harlan Krumholz, MD, Yale New Haven Hospital and Yale School of Medicine, New Haven, Connecticut, said in an interview. “But there is also information in the newspaper that we shouldn’t be complacent.”
He noted that rates of repeat AMI are still quite high, even though they are decreasing, and that there are missed opportunities to get AMI survivors to reduce their risk through proven medications, smoking cessation and blood pressure control.
“We should be happy with the progress, but we have to know that we are not finished; we still have a long way to go,” he said. “And then this health equity issue is still glaring.”
The researchers found that being black or being dual-eligible for Medicare and Medicaid was independently associated with higher 10-year all-cause mortality and recurrent risk of AMI.
The same is true for patients living in priority health zones, which researchers say are defined by consistently high adjusted mortality and hospitalization rates concentrated in the South.
After inverse propensity weighting, the adjusted mortality hazard ratios (RRs) were 1.05 for black patients compared to white patients, 1.24 for doubly eligible patients compared to non-eligible patients, and 1.05 .06 for residents of priority health zones compared to other zones.
“Black Americans and Medicare beneficiaries consistently lag their white counterparts in their survival experience,” Krumholz said. “We need to accelerate our improvement for black patients because there is no biological reason why they should lag behind in their outcomes. Race is a social construct and there is something going on when it comes to social determinants .”
Women had higher observed 10-year mortality and recurrence rates (75.2% and 27.8%, respectively) than men (70.6% and 26.6%). But after adjustment, this reversed and men had higher RRs for both outcomes, at 1.13 and 1.07, respectively.
Over the 25-year study period, the observed 10-year mortality rate was 72.7% and the adjusted annual reduction was 1.5% (95% CI, 1.4 – 1.5 ).
Secondary analyzes showed that the 10-year mortality was 80.3% for patients with ST-segment elevation MI (STEMI) versus 72.2% for those with non-STEMI. The adjusted 10-year risk of death was 15% higher in patients with STEMI (RR, 1.15; 95% CI, 1.14, 1.16).
The 10-year recurrent AMI rate was 27.1%. This was three times higher than the 8.9% 1-year recidivism rate reported among Medicare beneficiaries in 2010, the authors note.
The adjusted annual reduction in recurrent AMI was 2.7% (95% CI, 2.6, 2.7). Additionally, having a recurrent AMI was associated with an 8 percentage point increase in 10-year mortality risk.
The median time to a repeat MI within 10 years was 488 days, suggesting the importance of follow-up for AMI survivors beyond the traditional one-year period, they suggest.
Krumholz noted that the data will need to be revisited in the wake of the COVID-19 pandemic, which has disrupted follow-up care for AMI patients and seen a significant drop in the number of MIs presenting to hospitals.
“There’s a lot to learn about what happened during the pandemic, but it’s likely that whatever inequities and issues we identify before the pandemic, if any, are likely only getting worse now.” , did he declare. “This is an urgent call to action to try to improve the areas we identify.”
The authors noted that they were unable to separate Hispanic ethnicity from white, black, and other race and that diagnostic codes were used to define comorbidities, which could have influenced the results. Other limitations are the inability to assess troponin levels and incorporate the use of secondary prevention medications, adherence to post-acute care medications, nursing home stays, health visits home and doctor’s office visits, which are associated with outcomes.
Krumholz disclosed personal fees for UnitedHealth, Element Science, Reality Labs, Aetna, Tesseract/4Catalyst, F-Prime, Siegfried & Jensen Law Firm, Arnold & Porter Law Firm, and Martin Law Firm/ Baughman; is co-founder of Refactor Health and HugoHealth; and is associated with grants and/or contracts from the United States Centers for Medicare & Medicaid Services through Yale New Haven Hospital and Johnson & Johnson through Yale University. No other disclosures were reported.
JAMA Cardiol. Published online May 4, 2022. Summary