Pro-protein convertase subtilisin/kexin 9 concentrations correlate with coronary artery disease atheroma burden in a Pakistani cohort with chronic chest pain.

OBJECTIVE: To determine the relationship between proprotein convertase subtilisin kexin 9 (PCSK9) levels and atheroma burden in Pakistanis presenting to an ambulatory centre with chest pain. METHODS: A prospective matched case-control study of 400 patients selected for presence/absence of angiographic disease referred between 2001 and 2003. A comprehensive cardiovascular disease risk factor profile was assessed including demographics, environmental and biochemical risk factors including insulin resistance and PCSK-9 levels. Coronary atheroma burden was quantified by Gensini score. RESULTS: In this population, PCSK-9 levels were weakly correlated (r = 0.23) with male gender (p = 0.06) and number of diabetes years (p = 0.09), and inversely with log10 of lipoprotein (a) concentration (p = 0.07) but not LDL-C. In multiple regression analysis, Gensini score was associated with age (p = 0.002), established angina (p = 0.001), duration of diabetes (p = 0.05), low HDL-C (p < 0.001), lipoprotein (a) (p = 0.01), creatinine (p < 0.001), C-Reactive Protein (p = 0.02) and PSCK-9 (p = 0.05) concentrations. PCSK9 added to the regression model. Neither total cholesterol nor LDL-C were significant risk factors in this study. CONCLUSIONS: Proprotein convertase subtilisin kexin 9 concentrations are correlated with atheroma burden in Indian Asian populations from the sub-continent, not taking statin therapy, independent of LDL-C or other CVD risk factors.

Angiographic coronary artery disease and high-sensitivity troponin-T in a native Pakistani cohort presenting with chronic chest pain.

OBJECTIVE: To determine the relationship between troponin-T levels and atheroma burden in Pakistanis presenting to an ambulatory centre with chest pain. METHODS: A prospective case-control study of 400 patients selected for presence/absence of angiographic disease referred between 2001 and 2003. A comprehensive cardiovascular disease (CVD) risk factor profile was assessed including demographics, environmental and biochemical risk factors including insulin resistance and troponin-T levels. Coronary atheroma burden was quantified by Gensini score. RESULTS: Clinically significant elevated troponin-T levels (> 30 pmol/l) were found in 40 patients (10%) with equal numbers in groups selected with or without angiographic disease. Troponin-T elevation (> 13 pmol/l) was present in 59 vs. 47 patients (30% vs. 24%; p = 0.04). Troponin-T levels did not correlate with any measured demographical, environmental, drug therapy or biochemical risk factor. No difference was found in concentrations of lipids, apolipoproteins, insulin resistance, C-reactive protein or sialic acid in cohorts stratified by troponin-T concentrations. In univariate analysis comparing patients with high (> 30 pmol/l) and low troponin-T levels (< 13 pmol/l) higher plasma total protein (91 g/l vs. 85 g/l; p = 0.01), increased immunoglobulin levels (41 g/l vs. 36 g/l; p = 0.02) and prevalence of hyperparathyroidism (40% vs. 21%; p = 0.04) were associated with higher troponin-T concentrations. CONCLUSIONS: This study shows that measurement of troponin-T is not an alternative to imaging in an Indian asian population, but that it does identify a separate potentially high-risk population that would not be identified by the use of imaging alone which is potentially at higher risk of CVD events.