Subjects: MI, myocardial infarction, OR, odds ratio, LDL-C, low-density lipoprotein cholesterol, ARTERY-DISEASE, RCT, randomized clinical trial, Cardiology and Cardiovascular Medicine, SERUM-LEVELS, EPIC-NORFOLK, ACUTE CORONARY SYNDROMES, TRIAL, epidemiology, genetics, INHIBITOR, MVE, major vascular events, EVENTS, Cardiometabolic Risk, SNP, single-nucleotide polymorphism, drug development, sPLA2, secretory phospholipase A2, cardiovascular diseases, CI, confidence interval, ACS, acute coronary syndrome(s), Clinical Research, RISK, MENDELIAN RANDOMIZATION, HEALTHY-MEN
Objectives:\ud This study sought to investigate the role of secretory phospholipase A2 (sPLA2)-IIA in cardiovascular disease.
\ud \ud Background:\ud Higher circulating levels of sPLA2-IIA mass or sPLA2 enzyme activity have been associated with increased risk of cardiovascular events. However, it is not clear if this association is causal. A recent phase III clinical trial of an sPLA2 inhibitor (varespladib) was stopped prematurely for lack of efficacy.
\ud \ud Methods:\ud We conducted a Mendelian randomization meta-analysis of 19 general population studies (8,021 incident, 7,513 prevalent major vascular events [MVE] in 74,683 individuals) and 10 acute coronary syndrome (ACS) cohorts (2,520 recurrent MVE in 18,355 individuals) using rs11573156, a variant in PLA2G2A encoding the sPLA2-IIA isoenzyme, as an instrumental variable.
\ud \ud Results:\ud PLA2G2A rs11573156 C allele associated with lower circulating sPLA2-IIA mass (38% to 44%) and sPLA2 enzyme activity (3% to 23%) per C allele. The odds ratio (OR) for MVE per rs11573156 C allele was 1.02 (95% confidence interval [CI]: 0.98 to 1.06) in general populations and 0.96 (95% CI: 0.90 to 1.03) in ACS cohorts. In the general population studies, the OR derived from the genetic instrumental variable analysis for MVE for a 1-log unit lower sPLA2-IIA mass was 1.04 (95% CI: 0.96 to 1.13), and differed from the non-genetic observational estimate (OR: 0.69; 95% CI: 0.61 to 0.79). In the ACS cohorts, both the genetic instrumental variable and observational ORs showed a null association with MVE. Instrumental variable analysis failed to show associations between sPLA2 enzyme activity and MVE.
\ud \ud Conclusions:\ud Reducing sPLA2-IIA mass is unlikely to be a useful therapeutic goal for preventing cardiovascular events.