Does marital status contribute to the explanation of the hypercholesterolemia paradox in relation to long term mortality in myocardial infarction? Findings from the MONICA/KORA Myocardial Infarction Registry.

Objective: A recent study found long-term mortality after first acute myocardial infarction (AMI) to be particularly reduced among married individuals with hypercholesterolemia. This study explores, whether statin treatments during the last week prior to AMI offer an explanation to this phenomenon.

Methods: Data were retrieved 2000-2008 from the population-based KORA myocardial infarction registry, located in Bavaria, Germany. The sample included 3162 individuals, alive 28days after first AMI, who received statins both in hospital and at discharge. Associations with long-term mortality were examined via multivariable Cox regression. Among patients with hypercholesterolemia, individuals with and without prior statin treatment were each tested against the reference group "neither (hypercholesterolemia nor statin)" and tested for interaction with "marital status".

Results: Among patients with and without prior statins, hazard ratio (HR) 0.66, 95% confidence interval (CI) 0.46-0.93 and HR 0.72, 95% CI 0.55-0.94, were observed, respectively. Mortality reductions diminished after introduction of the following interaction terms with marital status: HR 0.49, p 0.042 for patients with and HR 0.77, p 0.370, for patients without prior statins.

Conclusions: Prior statin treatments appear to be an underlying factor for long-term mortality reduction in married AMI-survivors with hypercholesterolemia. Confirmation of our results in further studies is warranted.