High-density lipoprotein cholesterol and multiple sclerosis: a systematic review and meta-analysis

Multiple sclerosis (MS) is a chronic inflammatory disease of the central nervous system characterized by demyelination and axonal degeneration. Evidence has shown that lipid metabolism is associated with MS clinical outcomes. The aim was to systematically investigate the association between high-density lipoprotein cholesterol (HDL-C) and disease activity in MS.

Medline via PubMed, the Cochrane Library and Clinicaltrials.gov databases were searched for studies with data on HDL-C in patients with MS. A qualitative synthesis of published prospective and retrospective studies on the role of HDL-C and other lipid profile parameters in MS was performed. Additionally, a meta-analysis on HDL-C mean differences (MD) between relapsing remitting MS (RRMS) cases and healthy controls (HC) was performed.

Literature search identified 13 eligible studies evaluating the HDL-C levels of RRMS patients. In total, 1692 participants were included, 859 of which were RRMS patients, and 833 were HC. The pooled analysis demonstrated that RRMS patients had significantly lower HDL-C levels compared with HC (MD: -3.35 mg/dl, 95% CI (-5.69, -1.01), p = 0.005). Regarding triglycerides (TG) and total cholesterol (TC), the pooled analysis from 11 and 13 studies, respectively, showed significantly higher TG (MD = 26.33, 95% CI (15.03, 37.62), p < 0.00001) and TC levels (MD = 11.03, 95% CI (0.45, 21.60), p = 0.04) in RRMS versus HC. No significant differences were observed in low-density lipoprotein cholesterol levels between RRMS and HC.

HDL-C levels were significantly decreased in RRMS patients compared with HC. HDL-C and other lipid profile parameters should be considered in the assessment of patients with RRMS.