Lipid Levels During Adult Lifetime in Men and Women With and Without a Subsequent Incident Myocardial Infarction: A Longitudinal Analysis of Data From the Tromsø Study 1974 to 2016

BACKGROUND: The atherosclerotic effect of an adverse lipid profile is assumed to accumulate throughout life, leading to increased risk of myocardial infarction (MI). Still, little is known about age at onset and duration of unfavorable lipid levels before MI. METHODS AND RESULTS: Longitudinal data on serum lipid levels for 26 130 individuals (50.5% women, aged 20–89 years) were obtained from 7 population‐based health surveys in Tromsø, Norway. Diagnoses of MI were obtained from national registers. A linear mixed model was applied to compare age‐ and sex‐specific mean values of total cholesterol, high‐density lipoprotein cholesterol (HDL‐C), and triglyceride concentration by MI status (MI versus non‐MI). Already from young adulthood, 20 to 35 years before the incident MI, individuals with a subsequent incident MI had on average more adverse lipid levels than individuals of the same age and sex without MI. Analogous to a dose–response relationship, there was a clear trend toward more severe adverse lipid levels the lower the age at incident MI (P<0.001, test for trend through ordered categories <55, 55–74, ≥75 years). This trend was particularly pronounced for high‐density lipoprotein cholesterol in percentage of total cholesterol (both sexes) and for the relative relationship between triglyceride, high‐density lipoprotein cholesterol, and total cholesterol level (women). The difference in mean lipid level by MI status was just as large in women as in men, but the age pattern differed (P≤0.05, tests of 3‐way interaction). CONCLUSIONS: Compared with general population mean levels, adverse lipid levels were seen 20 to 35 years before the incident MI in both men and women.