Fluctuations in depression and anxiety predict dysregulated leptin among obese breast cancer survivors.

PURPOSE Leptin influences inflammation and tumor growth and leptin signaling is often dysregulated among obese breast cancer survivors. This leads to a lack of satiety and, ultimately, risk for further weight gain. Breast cancer survivors also experience high rates of depression and anxiety, which are linked to leptin production. This study examined how a woman's anxiety and depressive symptoms, in combination with their obesity status, were associated with leptin. METHODS Breast cancer survivors (n = 200, stages 0-IIIa) completed a baseline visit before treatment and two follow-up visits, 6 and 18 months after treatment ended. Women completed anxiety and depression measures, and blood samples provided leptin data at each visit. This study related fluctuations in a survivor's own depression and anxiety (i.e., within-person effects), as well as average effects of depression and anxiety (i.e., between-person effects) to changes in leptin depending on BMI. RESULTS Obese survivors' leptin was significantly higher at visits when they had higher anxiety and depression symptoms than their own average level of symptoms. In contrast, within-person fluctuations in depression and anxiety were not related to leptin levels among non-obese survivors. No significant between-person effects of depression or anxiety on leptin emerged. CONCLUSIONS Leptin is a critical risk factor for recurrence and further health consequences. Our findings highlight how psychological health influences leptin production among breast cancer survivors. IMPLICATIONS FOR CANCER SURVIVORS These results highlight a biological pathway that may facilitate further weight gain and health risks among distressed, obese breast cancer survivors.