Lowered quality of life in mood disorders is associated with increased neuro‐oxidative stress and basal thyroid‐stimulating hormone levels and use of anticonvulsant mood stabilizers

RATIONALE, AIMS: Major affective disorders including bipolar disorder (BD) and major depressive disorder (MDD) are associated with impaired health-related quality of life (HRQoL). Oxidative stress and subtle thyroid abnormalities may play a pathophysiological role in both disorders. Thus, the current study was performed to examine whether neuro-oxidative biomarkers and thyroid-stimulating hormone (TSH) levels could predict HRQoL in BD and MDD. METHODS: This cross-sectional study enrolled 68 BD and 37 MDD patients and 66 healthy controls. The World Health Organization (WHO) QoL-BREF scale was used to assess 4 QoL subdomains. Peripheral blood malondialdehyde (MDA), advanced oxidation protein products, paraoxonaxe/CMPAase activity, a composite index of nitro-oxidative stress, and basal TSH were measured. RESULTS: In the total WHOQoL score, 17.3% of the variance was explained by increased advanced oxidation protein products and TSH levels and lowered CMPAase activity and male gender. Physical HRQoL (14.4%) was associated with increased MDA and TSH levels and lowered CMPAase activity. Social relations HRQoL (17.4%) was predicted by higher nitro-oxidative index and TSH values, while mental and environment HRQoL were independently predicted by CMPAase activity. Finally, 73.0% of the variance in total HRQoL was explained by severity of depressive symptoms, use of anticonvulsants, lower income, early lifetime emotional neglect, MDA levels, the presence of mood disorders, and suicidal ideation. CONCLUSIONS: These data show that lowered HRQoL in major affective disorders could at least in part result from the effects of lipid peroxidation, protein oxidation, lowered antioxidant enzyme activities, and higher levels of TSH.