High LDL-cholesterol following heart attack lowers mortality: BMJ
USA: The presence of high LDL-cholesterol (hyperlipidemia) following a heart attack in hospitalized patients lowers mortality risk, a recent study published in the journal BMJ Open has found.
According to the study, concurrent hyperlipidemia (HLP) following hospitalization for acute myocardial infarction (AMI) or acute decompensated heart failure (ADHF) was associated with lower mortality, compared with no hyperlipidemia.
"Among patients who had a heart attack or heart failure, and who had concurrent hyperlipidemia or no hyperlipidemia, there was a clear difference in mortality," wrote the authors. "Patients who had hyperlipidemia had lower mortality than patients who had no hyperlipidemia."
Mohammed Yousufuddin, Internal Medicine, Mayo Clinic Minnesota, Rochester, Minnesota, USA, and colleagues evaluated adult patients who were hospitalized at the Mayo Clinic between 1996 and 2015 who with primary discharge diagnoses of AMI or ADHF in this systematic review and meta-analysis. All patients were followed from index hospitalization until death or August 17, 2016, whichever occurred first. Researchers assembled 1:1 propensity score-matched pairs of patients with AMI or ADHF to balance differences in baseline variables between patients with vs without HLP. The study's main outcome was all-cause mortality.
The AMI group had 13,680 patients in the initial cohort, 8696 patients in the propensity score-matched cohort, and 4348 patient-pairs. The ADHF group had 9717 patients in the initial cohort, 5758 patients in the propensity score-matched cohort, and 2879 patient-pairs.
Key findings of the study include:
- In matched cohorts, the mortality was lower in AMI patients (n=4348 pairs) with HLP versus no HLP, 5.9 versus 8.6/100 person-years of follow-up, respectively (HR 0.76).
- A similar mortality reduction occurred in matched ADHF patients (n=2879 pairs) with or without HLP (12.4 vs 16.3 deaths/100 person-years; HR 0.80).
- HRs showed modest reductions when HLP occurred concurrently with other comorbidities.
- Meta-analyses of nine observational studies showed that HLP was associated with lower mortality at ≥2 years after incident AMI or ADHF (AMI: RR 0.72; heart failure (HF): RR 0.67).
"Our data support a protective role for HLP against all-cause mortality following incident AMI and ADHF. Further studies are needed to understand the complex relationship between HLP and mortality, especially in the presence of other competing comorbidities and to define appropriate HLP targets to maximize the benefits" concluded the authors.
The study, "Association between hyperlipidemia and mortality after incident acute myocardial infarction or acute decompensated heart failure: a propensity score matched cohort study and a meta-analysis," is published in the journal BMJ Open.
