Stress, COMT polymorphisms, and depressive symptoms in older Australian women: an exploratory study

Objectives: This exploratory study examined the association between exposure to stressful life events, polymorphisms (rs165774 and rs4680) in the catechol-O-methyltransferase (COMT) gene, and risk of depression in women. Materials and Methods: A cross-sectional design gathered information from 150 Australia women, aged 60–70 years, on sociodemographics, stressful life events, and depressive symptoms. Participants also provided buccal cell swabs for genetic analysis. Results: Among women exposed to stressful life events, the odds of depressive symptoms increased by 18% with each additional exposure (95% confidence interval [95% CI] 1.04–1.33, p = 0.007). Women who carried at least one “A” allele (AA/AG) for both rs165774 and rs4680 single nucleotide polymorphisms were less likely to report depressive symptoms (compared with women with the GG genotype; p = 0.019 and p = 0.037, respectively), although moderation analysis did not support the hypotheses of an interaction with stressful life events (rs165774: odds ratio [OR] = 1.13, 95% CI 0.87–1.46, p = 0.347; rs4680: OR = 1.15, 95% CI 0.91–1.44, p = 0.238). Conclusion: Our research suggests that women with polymorphisms in COMT were less susceptible to depressive symptoms but these polymorphisms do not appear to influence susceptibility to depression in those exposed to life stressors. Further research should consider other genetic variants in catecholamine pathways and their potential impact on women's mental health