Pattern of circulating endothelial-derived microparticles among chronic heart failure patients with dysmetabolic comorbidities: The impact of subclinical hypothyroidism

Summary The study aim was to evaluate the impact of dysmetabolic comorbidities including subclinical hypothyroidism (SH) on pattern of circulating endothelial-derived microparticles (EMPs) in chronic heart failure (CHF) patients. Methods It was retrospectively involved a cohort of 388 patients with CHF. Fifty three CHF subjects had SH and 335 patients were free from thyroid dysfunction. Circulating levels of NT-pro brain natriuretic peptide (NT-pro-BNP), high-sensitivity C-reactive protein (hs-CRP), thyroid stimulating hormone (TSH), total and free thyroxine (T4) and triiodothyronine (T3) EMPs were measured at baseline. SH was defined per contemporary clinical guideline as state associated with elevated level of serum TSH > 10 μU/L and basal normal free T3 and T4 concentration. Results Circulating CD31+/annexin V+ EMPs were higher in SH patients compared with none SH subjects. In contrast, activated CD62E+ EMP numbers were not significantly different between both patient cohorts. Using C-statistics for Models with TSH, New York Heart Association (NYHA) class, dyslipidemia, and circulating biomarkers (hs-CRP, NT-proBNP, serum uric acid) as Continuous Variables we found that adding of NYHA class alone, NT-proBNP alone or their combination to the based model (TSH) improved the relative integrated discrimination improvement (IDI) for increased CD31+/annexin V+ to CD62E+ ratio by 4.9%; 9.2% and 9.6% respectively. NT-proBNP improves significantly predictive model based on TSH for increased CD31+/annexin V+ to CD62E+ ratio. Among patient study population for category-free net reclassification improvement (NRI), 4% of events ( P  = 0.026) and 6% of non-events ( P  = 0.012) were correctly reclassified by the addition of circulating NT-proBNP to the base model (TSH) for Increased CD31+/annexin V+ to CD62E+ ratio. Therefore, 4% of events ( P  = 0.028) and 5% of non-events ( P  = 0.014) were correctly reclassified using category-free NRI for increased CD31+/annexin V+ to CD62E+ ratio. Conclusion We found that SH state in CHF patients associates with impaired pattern of circulating EMPs with predominantly increased number of apoptotic-derived microparticles.