Perceived physical fatigability improves after an exercise intervention among breast cancer survivors: a randomized clinical trial.

BACKGROUND: Among breast cancer populations, exercise interventions resulted in positive but relatively small improvements on fatigue, which may be due to insensitive measures of global fatigue. Perceived fatigability-whole-body tiredness anchored to standardized tasks/activities of a specific intensity and duration-may help to detect effective exercise interventions reducing fatigue in oncology. We examined whether perceived physical fatigability improved after an exercise intervention. METHODS: This single center randomized clinical trial of 49 breast cancer survivors was conducted from 2015 to 2017, among which 41 participants (22 = exercise, 19 = control) completed the trial and reported their perceived physical fatigability at the first (Visit 1) and the last visit (Visit 3) over 6-14 weeks. Perceived physical fatigability was measured using the 10-item, self-administered Pittsburgh Fatigability Scale (PFS) scored 0-50. The mean differences of perceived physical fatigability between Visit 3 and Visit 1 were computed and compared by intervention groups using two sample t test. RESULTS: Among the 41 women in the study (mean age 54.9 ± 9.8 years; 80% white), sociodemographic, clinical characteristics and baseline fatigue level were similar by intervention groups, except for antiestrogen use. Post-intervention changes (mean ∆ ± SE) of PFS Physical scores were greater in the exercise group (- 4.4 ± 1.4; - 22.5%) than the control group (0.2 ± 1.4; + 1.0%) (p = .022). CONCLUSION: The PFS captured a reduction in fatigue after the exercise intervention among breast cancer survivors. These findings aid mounting efforts to reduce fatigue in oncology by introducing a more sensitive instrument to measure perceived physical fatigability to better evaluate patient-reported outcomes in future cancer trials. TRIAL REGISTRATION: Clinicaltrials.gov identifier: NCT02770781.

Relationship Between Personality Measures and Perceived Mental Fatigability.

OBJECTIVE: Examine the association between personality measures and perceived mental fatigability. METHODS: We performed a cross-sectional analysis in N=1670 men, age 84.3±4.1 years. Multivariable linear regression models were used to examine the covariate adjusted association between personality measures (conscientiousness, optimism, goal reengagement, and goal disengagement) and perceived mental fatigability (measured with the validated 10-item Pittsburgh Fatigability Scale, PFS). RESULTS: One standard deviation lower conscientiousness (ß=-0.91, p<.0001) and optimism (ß=-0.63, p<.0001), and higher goal reengagement (ß=0.51, p=.01) scores were independently associated with higher PFS Mental scores adjusted for age, cognitive function, self-reported health status, depressive symptoms, sleep disturbance, physical activity, and goal disengagement. DISCUSSION: Lower conscientiousness, optimism, and higher goal reengagement were linked with more severe perceived mental fatigability in older men. Personality traits may potentially contribute to early risk assessment for fatigability in later life. Future work should be longitudinal in nature and include personality assessments to confirm the temporality of the relationships observed.