Oxidative balance and mental health: Exploring the link between prooxidant-antioxidant balance and depression in hypertensive and normotensive individuals, accounting for sex differences.

Background: Existing studies have suggested a link between oxidative stress levels and depression. Additionally, factors such as gender and conditions like hypertension have been shown to influence oxidative stress. This ten-year follow-up cohort study aims to examine the association between prooxidant-antioxidant balance (PAB) and the onset of depression and its symptoms in both hypertensive and normotensive individuals, while considering gender differences.

Methods: The data for this study was obtained from the Mashhad Stroke and Heart Atherosclerotic Disorder (MASHAD) study, a cohort study conducted in eastern Iran. Serum PAB levels were measured in 1702 hypertensive and 4096 normotensive individuals aged 35 to 65 years. After ten years, the participants' depression status was evaluated using the Beck questionnaire, and depression symptoms were investigated using the BDI-II structural model, which includes somatic, affective, and cognitive symptoms.

Result: The analysis indicates that in hypertensive male participants, the highest tertile of PAB is associated with an increased risk of depression (β: 1.22, 95 % CI: -0.046, 2.485; P = 0.059) and symptoms of depression, including cognitive (β: 2.937, 95 % CI: 0.511, 5.362; P = 0.018) and somatic (β: 2.654, 95 % CI: 0.37, 4.939; P = 0.023) symptoms. However, there was no significant association between affective symptoms and PAB tertiles. Additionally, there was no significant link between depression and depressive symptoms in female hypertensive and normotensive individuals.

Conclusion: In male hypertensive patients, but not in normotensive individuals of both genders and hypertensive women, depression and its associated symptoms, including somatic and cognitive symptoms, are associated with elevated levels of oxidative stress, as evidenced by higher serum PAB values. PAB is not associated with affective symptoms. Future studies should focus on the gender-specific nature of this relationship and work to clarify its underlying mechanisms.