Longitudinal Analysis of Psychoneurological Symptoms and the Gut Microbiome in Patients With Melanoma Receiving Immune Checkpoint Inhibitors

OBJECTIVES: To characterize the severity of psychoneurological (PN) symptoms in cancer survivors who initiated immune checkpoint inhibitors (ICIs) at baseline and 12 weeks post-treatment and to examine the associations between PN symptoms and gut microbiome patterns. SAMPLE AND SETTING: 15 patients (n = 9 males and n = 6 females, mean age = 70.9 years) with solid tumors who initiated ICIs were recruited from a cancer center. METHODS AND VARIABLES: PN symptoms were assessed using self-report questionnaires, and stool samples were analyzed using 16S rRNA sequencing. Alpha and beta diversity indices were calculated, and a least absolute shrinkage and selection operator regression model was fitted to assess associations between each symptom and the log-ratio of the genus abundance. RESULTS: Average fatigue levels increased during 12 weeks. The microbiome community varied by age, sex, and their interaction. At 12 weeks post-treatment, Oscillibacter (beta = -0.141), Limosilactobacillus (beta = 0.088), and Erysipelotrichaceae (beta = -0.021) were associated with average levels of fatigue, whereas Tannerellaceae (beta = -0.011), Bacteroides (beta = 0.474), and Acidaminococcus (beta = 0.193) were associated with pain severity (all p < 0.05). IMPLICATIONS FOR NURSING: Given the potential association between the gut microbiome and PN symptoms during ICI treatment, nurses are encouraged to assess dysbiosis risk, screen for treatment-related adverse symptoms, and educate patients about gut health while receiving ICIs.