Sex differences in subjective cognitive impairment among Chinese patients with depression: A large-scale...

Cognitive impairment is common in major depressive disorder (MDD) and is associated with impaired social functioning and an increased risk of relapse. Although sex differences in MDD are well documented, their specific role in subjective cognitive impairment (SCI) and related clinical correlates remains unclear.

This study aimed to examine sex differences in SCI and its associated clinical risk factors within a large cohort of Chinese patients with MDD.

This cross-sectional study included 2298 adults with MDD (665 males, 1633 females; mean [standard deviation] age, 30.88 [10.33] years). Sociodemographic and clinical characteristics were collected electronically. Participants completed the Patient Health Questionnaire-9 (PHQ-9) for depressive symptoms, Generalised Anxiety Disorder-7 (GAD-7) for anxiety symptoms, 20-item Perceived Deficits Questionnaire-Depression (PDQ-D-20) for SCI and 20-item Toronto Alexithymia Scale (TAS-20) for alexithymia. Analysis of covariance and binary logistic regression were used to analyse sex differences in SCI and associated factors. Interaction analyses assessed whether these associations differed by sex, and sensitivity analyses used a more stringent SCI cutoff. The Benjamini-Hochberg false discovery rate (FDR) correction was applied to account for multiple testing.

Of the 2298 participants, 67.9% (n = 1561) met the criterion for SCI. Females had significantly higher PDQ-D-20 scores than males (adjusted mean, 31.65 vs. 30.06; F = 6.25, p = 0.013) and a higher prevalence of SCI (69.8% vs. 63.3%, χ ² = 9.17, p = 0.002). In both sexes, SCI was associated with TAS-20 scores (males: odds ratio [OR] = 1.08, 95% confidence interval [CI] 1.05-1.10; females: OR = 1.07, 95% CI 1.06-1.09) and PHQ-9 scores (males: OR = 1.17, 95% CI 1.11-1.24; females: OR = 1.12, 95% CI 1.08-1.16) (all p < 0.001; p-FDR < 0.001). GAD-7 scores were associated with SCI only among female patients (OR = 1.05, 95% CI 1.01-1.09; p = 0.008; p-FDR = 0.014), and this finding remained robust in sensitivity analyses. No interaction with sex was significant in the primary analysis (all p > 0.05), but a significant sex × TAS-20 interaction was observed under the more stringent cutoff (OR = 1.03, 95% CI 1.00-1.06; p = 0.024; p-FDR = 0.036).

This study identifies significant sex differences in SCI among Chinese patients with MDD. Female patients reported greater SCI, and anxiety symptoms were associated with SCI only in the female subgroup. These findings support further investigation of sex-sensitive approaches to assessing and managing cognitive complaints in MDD.