The relationship between ambulatory step activity, self-reported physical functioning and standardised timed walking in patients with haematological malignancies

Are patient-reported outcomes of physical function a valid substitute for objective measurements?

Background

Physical function is important for defining treatment strategies in patients with cancer and can be estimated using patient-reported outcomes (pros). Although pros are subjective, physical activity and fitness can be tested objectively with adequate, but more labour-intensive methods that are rarely used in daily clinical practice. To determine whether pros for physical function (pro-pf) accurately predict physical function, we studied their interrelationships with objective measures of physical activity and fitness in patients with cancer who had completed cancer treatment, including adjuvant or neoadjuvant chemotherapy or autologous stem-cell transplantation.

Methods

Baseline data from the react (Resistance and Endurance Exercise After Chemotherapy) and exist (Exercise Intervention After Stem-Cell Transplantation) studies were evaluated. In those studies, the effects of an exercise intervention on physical fitness, fatigue, and health-related quality of life in patients with cancer shortly after completion of chemotherapy or stem-cell transplantation were studied. Interrelationships between pro-pf (physical function subscale of the European Organisation for Research and Treatment of Cancer 30-question core Quality of Life Questionnaire), physical activity (accelerometer), and cardiorespiratory fitness (peak oxygen uptake) were assessed using univariable and multivariable multilevel linear mixed-model analyses.

Results

After adjustment for age, sex, and body mass index, the pro-pf was significantly associated with physical activity (β = 1.75; 95% confidence interval: 1.08 to 2.42) and cardiorespiratory fitness (β = 0.10; 95% confidence interval: 0.06 to 0.13). Standardized coefficients were 0.28 and 0.26 respectively, indicating a weak association.

Conclusions

The pro-pf is only weakly associated with objective physical activity and fitness evaluation in patients after curative treatment for cancer. The pro-pf cannot, therefore, be used in clinical practice as a substitute for objective measures of physical function.

Mobility in Old Age: Capacity Is Not Performance

Background. Outcomes of laboratory-based tests for mobility are often used to infer about older adults' performance in real life; however, it is unclear whether such association exists. We hypothesized that mobility capacity, as measured in the laboratory, and mobility performance, as measured in real life, would be poorly linked. Methods. The sample consisted of 84 older adults (72.5 ± 5.9 years). Capacity was assessed via the iTUG and standard gait parameters (stride length, stride velocity, and cadence). Performance was assessed in real life over a period of 6.95 ± 1.99 days using smartphone technology to calculate following parameters: active and gait time, number of steps, life-space, mean action-range, and maximum action-range. Correlation analyses and stepwise multiple regression analyses were applied. Results. All laboratory measures demonstrated significant associations with the real-life measures (between r = .229 and r = .461). The multiple regression analyses indicated that the laboratory measures accounted for a significant but very low proportion of variance (between 5% and 21%) in real-life measures. Conclusion. In older adults without mobility impairments, capacity-related measures of mobility bear little significance for predicting real-life performance. Hence, other factors play a role in how older people manage their daily-life mobility. This should be considered for diagnosis and treatment of mobility deficits in older people.

Exercise and stress management training prior to hematopoietic cell transplantation: Blood and Marrow Transplant Clinical Trials Network (BMT CTN) 0902

Studies show that engaging patients in exercise and/or stress management techniques during hematopoietic cell transplantation (HCT) improves quality of life. The Blood and Marrow Transplant Clinical Trials Network tested the efficacy of training patients to engage in self-directed exercise and stress management during HCT. The study randomized 711 patients at 21 centers to receive 1 of 4 training interventions before HCT: a self-directed exercise program, a self-administered stress management program, both, or neither. Participants completed self-reported assessments at enrollment and up to 180 days after HCT. Randomization was stratified by center and transplant type. There were no differences in the primary endpoints of the Physical Component Summary and Mental Component Summary scales of the Medical Outcomes Study Short Form 36 at day +100 among the groups, based on an intention-to-treat analysis. There also were no differences in overall survival, days of hospitalization through day +100 post-HCT, or in other patient-reported outcomes, including treatment-related distress, sleep quality, pain, and nausea. Patients randomized to training in stress management reported more use of those techniques, but patients randomized to training in exercise did not report more physical activity. Although other studies have reported efficacy of more intensive interventions, brief training in an easy-to-disseminate format for either self-directed exercise or stress management was not effective in our trial.

Cardiopulmonary fitness in patients undergoing hematopoietic SCT: a pilot study

Hematopoietic cell transplantation (HCT) is a life-saving treatment for patients with high-risk hematological malignancies. Prognostic measures to determine fitness for HCT are needed to inform decision-making and interventions. VO(2peak) is obtained by measuring gas exchange during cycle ergometry and has not been studied as a prognostic factor in HCT. Thirty-two autologous and allogeneic HCT patients underwent VO(2peak) and 6 Minute Walk (6MW) testing before HCT, and provided weekly symptom and health-related quality of life (HRQOL) assessments before HCT and concluding at Day 100. Twenty-nine patients completed pre-HCT testing. Pre-HCT VO(2peak) was positively correlated with pre-HCT 6MW (r=0.65, P<0.001) and negatively correlated with number of chemotherapy regimens and months of chemotherapy. Patients with lower VO(2peak) reported higher symptom burden and inferior HRQOL at baseline and during early post-HCT period. Patients with pre-HCT VO(2peak) <16 mL/kg/min had higher risk of mortality post HCT (entire cohort: hazard ratio (HR) 9.1 (1.75-47.0), P=0.01; allogeneic HCT patients only: HR 6.70 (1.29-34.75), P=0.02) and more hospitalized days before Day 100 (entire cohort: median 33 vs 19, P=0.003; allogeneic HCT patients only: median 33 vs 21, P=0.004). VO(2peak) pre-HCT is feasible and might predict symptom severity, HRQOL and mortality. Additional studies are warranted.