Impact of 36 months of androgen-deprivation therapy (ADT) on physical function and quality of life (QOL) in men with nonmetastatic prostate cancer.

Abstract

16 Background: Use of ADT has been shown to adversely affect physical function and QOL within 3 months of initiation; declines persist at 12 months. Few studies have examined physical function with ongoing ADT use beyond 12 months. Methods: In this extension of our prior study, men age 50 or older with non-metastatic prostate cancer (PC) who were on continuous ADT were followed along with two control groups (PC, no ADT; healthy controls) matched on age, education, and baseline function. Physical function was assessed with the 6-minute walk test (6MWT), grip strength, and the Timed Up and Go (TUG) test, representing endurance, upper extremity strength, and lower extremity strength, respectively. Aggregate physical and mental QOL were measured with the Medical Outcomes Study SF-36. Assessments were done at baseline and at 3, 6, 12, 18, 24, 30, and 36 months. Mixed effects regression models were used, adjusting for age, baseline function, and other covariates. Results: 87 patients on ADT, 86 PC controls, and 86 healthy controls were enrolled (mean age 69.4 y, range 50-87). At baseline, all three groups were similar in age and physical function (all ANOVA p>0.05) and most subjects were otherwise quite healthy. 6MWT distance improved in both control groups but remained unchanged in ADT users (p=0.0379). Grip strength declined sharply in the ADT group by 3 months and remained stable up to 36 months (p<0.001), whereas both control groups were stable over time. There was a slight worsening of TUG scores in the ADT group over 36 months (p=0.0003) but were unchanged in both control groups (p>0.10). Aggregate physical QOL continued to decline in ADT users over time (p=0.0002) but remained stable in both control groups over 36 months, whereas aggregate mental QOL was stable in all groups over time. Most declines were evident within 3-6 months of ADT initiation. Conclusions: Initial declines with continuous ADT use in both physical function and aggregate physical QOL persist for 36 months but generally did not decline further beyond one year despite ongoing ADT use. Early exercise interventions and/or intermittent ADT use may improve these outcomes.