A meta-analysis of lipid peroxidation markers in major depression

BACKGROUND Major depressive disorder (MDD) may be associated with oxidative damage to lipids, which can potentially affect mood-regulating pathways. This meta-analysis summarizes current knowledge regarding lipid peroxidation markers in clinical samples of MDD and the effects of antidepressant pharmacotherapy on those markers. METHODS MEDLINE, EMBASE, CINAHL, PsycINFO, and Cochrane Collaboration were searched for original, peer-reviewed articles measuring markers of lipid peroxidation in patients with MDD and nondepressed healthy controls up to April 2015. Standardized mean differences (SMDs) were generated from random effects models summarizing mean (± standard deviations) concentrations of selected markers. RESULTS Lipid peroxidation was greater in MDD than in controls (studies =17, N=857 MDD/782 control, SMD =0.83 [0.56-1.09], z=6.11, P<0.01, I (2)=84.0%) and was correlated with greater depressive symptom severity (B=0.05, df=8, P<0.01). Antidepressant treatment was associated with a reduction in lipid peroxidation in MDD patients (studies=5, N=222, SMD=0.71 [0.40-0.97], P<0.01; I (2)=42.5%). LIMITATIONS Lipid peroxidation markers were sampled from peripheral blood, included studies comparing MDD to controls were all cross-sectional, and only five antidepressant treatment studies were eligible for inclusion. CONCLUSION Increased lipid peroxidation was associated with MDD and may be normalized by antidepressants. Continued investigation of lipid peroxidation in MDD is warranted.