Background: C-reactive protein (CRP) has been proposed as a risk marker and risk factor of cardiovascular disease. There have been a number of clinical reports suggesting that supplementation with L-carnitine can modulate systemic inflammation and lower circulating CRP concentrations, but the results have not been consistent.
Methods: A comprehensive literature search in Medline, Scopus and Cochrane Central Register of Controlled Trials was performed in December 2012 to identify clinical trials investigating the impact of oral L-carnitine supplementation on serum/plasma CRP concentration. A random effect method was used to calculate the combined effect size.
Results: Six studies comprising 541 cases and 546 controls met the inclusion criteria. Meta-analysis of included trials revealed a significant reduction of circulating CRP concentrations in subjects under L-carnitine intervention compared to the control treatment. The calculated combined weighted mean reduction in CRP concentrations was -0.39 mg/L [95% CI (-0.62 - -0.16)]. This effect size estimate was found to be robust and remained unaffected by the removal of each single study.
Conclusions: The overall findings of the present meta-analysis support the clinically relevant benefit of L-carnitine supplementation in lowering the circulating levels of CRP.
Uvod: C-reaktivni protein (CRP) predložen je kao marker rizika i faktor rizika za kardiovaskularnu bolest. Postoji izvestan broj kliničkih izveštaja koji su pokazali da suplementacija L-karnitinom može modulisati sistemsku inflamaciju i sniziti koncentracije CRP-a u cirkulaciji, ali njihovi rezultati nisu usaglašeni.
Metode: U decembru 2012, sprovedena je sveobuhvatna pretraga literature u bazama Medline, Scopus i Cochrane Central Register of Controlled Trials radi identifikacije kliničkih ispitivanja koja su istraživala uticaj oralne suplementacije L-karnitinom na koncentraciju CRP-a u serumu/plazmi. Za izračunavanje kombinovanih dimenzija efekta korišćena je metoda nasumičnog efekta.
Rezultati: Šest studija koje su obuhvatile 541 pacijenta i 546 kontrolnih subjekata ispunilo je kriterijume za uključenje u ovu studiju. Metaanalizom obuhvaćenih ispitivanja je otkriveno značajno sniženje koncentracija CRP-a u cirkulaciji kod subjekata podvrgnutih intervenciji L-karnitinom u poređenju s kontrolom. Izračunato kombinovano srednje sniženje koncentracija CRP-a iznosilo je −0,39 mg/L [95% CI(−0,62 – −0,16)]. Ovakva procena dimenzija efekta označena je kao robusna i ostala je nepromenjena i posle odstranjivanja svake pojedinačne studije.
Zaključak: Ukupni rezultat predstavljene metaanalize svedoči u prilog klinički relevantne koristi od suplementacije L-karnitinom za snižavanje nivoa CRP u cirkulaciji.
Keywords: atherosclerosis; carnitine; clinical trial; coronary artery disease; nutrition; systematic review.