Lipoprotein(a) and atherosclerotic cardiovascular disease in a Brazilian tertiary hospital population

Abstract Background/Introduction Elevated levels of lipoprotein(a) [Lp(a)] are a strong risk marker of atherosclerotic cardiovascular disease (ASCVD), including myocardial infarction (MI), ischemic stroke, and peripheral arterial disease, as well as of aortic valve calcification and stenosis. However, few studies have assessed the prevalence of high Lp(a) levels in patients followed at a tertiary hospital specialized in cardiovascular diseases (CVD). In addition, there is scant information about Lp(a) concentrations in Brazilian individuals. Purpose The aim of the study was to describe the demographic characteristics and comorbidities of patients with at least one measure of Lp(a) at a tertiary treatment center for CVD in our city – Brazil. Methods Patients treated at a heart institute had their data extracted between the years 1999 and 2021. Data were obtained through direct electronic extraction of patients' medical records. The patients were categorized according to different Lp(a) cutoff levels (> 50 and < 70, > 70 and < 90, and > 90 mg/dL) and by quartiles. Results Of 4,970 unique patients included in the study, the mean age at baseline was 59.9 years (SD ± 14.5), 2,634 (53%) were male, and the median Lp(a) was 23.2 mg/dL (interquartile range 8.9 - 56.8 mg/dL). In the whole cohort, 460 (9.3%) had Lp(a) > 50 and < 70, 344 (6.9%) > 70 and < 90, 612 (12.3%) > 90 mg/dl and 138 (2.8%) > 150 mg/dL. Established ASCVD was reported in 1,223 (24%) of the individuals, with a progressively higher prevalence across the Lp(a) categories above (31.2%, 33.8%, 34.2%, respectively) (table 1). Moreover, the Lp(a) median (interquartile range) in mg/dL was significantly higher in those with baseline history of ASCVD (31.4 [10.8-71.2] vs 21.2 [8.3-52]), MI (27.8 [10.6-65.9] vs 22.3 [8.5-54.7]) and stroke (24.9 [10-69.5] vs 23.1 [8.9-56.5]), all p < 0.05 (table 2). Lp(a) was also significantly higher among those with LDL-C ≥ 100 mg/dL relative to LDL-C < 100 mg/dl (25.5[9.5-63.2] vs 21.4[8.4 vs 52.2] p < 0.05). Conclusions In this cohort of patients followed at a tertiary center specialized in CVD, approximately a third had Lp(a) levels above 50 mg/dL, a cutoff robustly associated with ASCVD. This finding likely represents an important source of cardiovascular residual risk, particularly in those with established ASCVD, exposing the need of further therapies.