ReviewVariation of lipoprotein associated phospholipase A2 across demographic characteristics and cardiovascular risk factors: A systematic review of the literature

BackgroundLipoprotein association phospholipase A2 (Lp-PLA2), an enzyme which has been found in atherosclerotic plaque is currently under investigation in large Phase III clinical trials of vascular disease prevention. We assessed in a variety of different population settings variation of Lp-PLA2 mass and activity across gender, ethnicity, diabetes, kidney disease and metabolic syndrome. We also assessed correlations with measures of circulating lipids, systemic inflammation and adiposity.MethodsSystematic review of studies measuring Lp-PLA2 and at least one of the relevant characteristics in >50 participants.ResultsWe identified a total of 77 studies involving 102,499 participants meeting the inclusion criteria. Lp-PLA2 mass and activity were consistently approximately 10% higher in males than females and 15% higher in Caucasians than African Americans or Hispanics. There were no clear associations of Lp-PLA2 mass or activity with type II diabetes, markers of systemic inflammation (C-reactive protein, fibrinogen) or with body mass index. Correlations of Lp-PLA2 mass or activity with low density lipoprotein cholesterol and apolipoprotein B were moderate and positive, whilst correlations with high density lipoprotein cholesterol were negative and moderate to weak. There was no clear differences in associations with any of the above characteristics in groups defined based upon prevalent cardiovascular disease or its risk factors.ConclusionsDespite considerable variability in absolute levels of Lp-PLA2 across studies, the variability of Lp-PLA2 across gender, ethnicity, and levels of circulating lipids and markers of systemic inflammation are more consistent and appear not to vary importantly across categories defined by CVD or its risk factors.