Association between lipoprotein (a) and risk of heart failure: A systematic review and meta-analysis of Mendelian randomization studies

Background: Rising incidence of heart failure (HF) in the Western world despite advanced clinical care necessitate exploration of further preventive tools and strategies. Lipoprotein(a) [Lp(a)], recognized as one of the major cardiovascular risk factors has also been implicated as a risk factor for HF. However, existing evidence remains inconclusive and that has led us to perform this meta-analysis. Methods: PubMed/Medline, EMBASE and Scopus were systematically searched for studies evaluating an association of Lp(a) with occurrence of HF from inception-till November 2023. Random effects models and I² statistics were used for pooled odds ratio (OR) and heterogeneity assessment. We performed leave one out sensitivity analyses by sequentially removing one study at a time and recalculating the pooled effect size. Result: Our search rendered in total 360 studies and after final screening this resulted in 7 Mendelian randomization (MR) design. According to the MR analysis, increasing Lp(a) level were significantly associated with increased risk of HF (OR 1.064, 95 % CI: 1.043-1.086, I²= 97.59 %, P < 0.001). In addition, Leave-one-out sensitivity analysis showed that the effect size did not change substantially by removal of any particular study in MR studies and ORs ranged from 1.051 (when excluding Levin) to a maximum of 1.111 (when excluding Wang or Jiang), hereby confirming the association. Conclusion: We were able to show that by meta-analysis of MR data, increasing lipoprotein (a) levels are associated with an increased risk of HF. Whether this is due to a direct effect on heart muscle contraction or whether this is due to an increased risk of ischemic cardiac disease remains to be elucidated.