The kynurenine pathway in relation to depression and anhedonia symptom severity among women with HIV

The kynurenine pathway (KP) has been implicated in cytokine-induced depression and anhedonia, a core depression symptom. We examined KP metabolites in relation to depression and anhedonia symptom severity in women with and without HIV (WWH and WWoH). Participants included 239 women (55% WWH, mean age 52 years). Depressive symptoms were measured using the Center for Epidemiologic Studies Depression (CES-D) scale and high depressive symptoms were defined as a score ≥16; anhedonia severity was quantified on two CES-D items. KP metabolites, including quinolinic acid (QA, NMDA receptor agonist) and kynurenic acid (KA, NMDA receptor antagonist), were measured using liquid chromatography-tandem mass spectrometry. Adjusted multivariable linear regression was used to compare metabolites among groups and to assess relationships of KP metabolites with anhedonia and depressive symptoms. A greater proportion of WWH had high depression severity (CES-D ≥16) than WWoH (23% vs. 12%; p=0.03). WWH with CES-D > 16 had greater QA compared to WWH with CES-D