Low-density lipoprotein subclasses over the menopausal transition and risk of coronary calcification and carotid atherosclerosis: the SWAN Heart and HDL ancillary studies

OBJECTIVE: Perimenopausal women experience a steep increase in low-density lipoprotein cholesterol (LDL-C) that is related to a higher risk of carotid plaque later in life. Low-density lipoprotein subclasses have been linked to cardiovascular diseases beyond LDL-C, promising a better risk stratification. We aim to characterize changes in LDL subclasses and assess their associations with presence of coronary artery calcium (CAC score ≥10) and carotid intima-media thickness (cIMT) over the menopausal transition (MT) and by menopause stage. METHODS: Nuclear magnetic resonance spectroscopy LDL subclasses were measured for a maximum of five time points. Coronary artery calcification and cIMT were measured for a maximum of two time points. LOESS (locally weighted regression with scatter smoothing) plots, linear mixed-effects models, and generalized estimating equations were used for analyses. RESULTS: The study included 471 women (baseline: age, 50.2 ± 2.7 years; 79.0% premenopausal/early perimenopausal), of whom 221 had data on CAC or cIMT. Low-density lipoprotein subclasses increased over the MT, whereas intermediate density-lipoprotein particles declined. In adjusted models, higher total LDL particles (LDL-P) and apolipoprotein B were associated with greater CAC prevalence and greater cIMT. Although none of the associations were modified by menopause stage, higher LDL-C, apolipoprotein B, and total LDL-P were associated with greater cIMT during the perimenopause or postmenopause stages, whereas higher LDL-C and small LDL-P were associated with greater CAC prevalence, mainly during perimenopause. CONCLUSIONS: During the MT, women experience significant increases in LDL subclasses found to be related to greater cIMT levels and CAC prevalence. Whether these changes could better predict future risk of hard cardiovascular disease events beyond LDL-C remains a research question to address.