Purpose: This prospective longitudinal study evaluated the effect of androgen deprivation therapy (ADT) on objective and self-reported physical function.
Patients and methods: Men with nonmetastatic prostate cancer (PC) starting continuous ADT were enrolled in this matched cohort study. Physical function was assessed with the 6-minute walk test (6MWT), grip strength, and the timed-up-and-go (TUG) test, representing endurance and upper and lower extremity strength, respectively. Quality of life (QOL) was measured with the Medical Outcomes Study Short-Form 36 (SF-36) questionnaire. Subjects were assessed at baseline, 3, 6, and 12 months. Two control groups (PC without ADT; no PC), matched on age, education, and baseline function were enrolled. Mixed effects regression models were fitted, adjusting for baseline covariates.
Results: We enrolled 87 patients on ADT, 86 PC controls, and 86 healthy controls; groups were similar in age (mean, 69.1 years; range, 50 to 87) and physical function. The 6MWT distance remained stable in the ADT group (P = .96) but improved in both control groups (P < .05). Grip strength declined in the ADT group (P = .04), remained stable in PC controls (P = .31), and improved in healthy controls (P = .008). TUG scores remained stable over time and across groups (P > .10). The SF-36 physical function summary score declined in the ADT group (P < .001), but increased in both control groups (P < .001). Negative effects on outcomes were observed within 3 months of starting ADT and were generally independent of age.
Conclusion: Endurance, upper extremity strength, and physical components of QOL are affected within 3 months of starting ADT. Up-front exercise interventions to counteract these losses are warranted.