Reliability of Ambulatory Walking Activity in Patients With Hematologic Malignancies

Abstract

Objectives To determine the relative and absolute reliability of the assessment of ambulatory walking activity during 2 consecutive weeks in patients with hematologic malignancies recovering at home from their medical treatment and to compare the physical activity level of hematologic cancer patients after high-dose chemotherapy with healthy subjects. Design Testretest study of 2 consecutive 7-day recordings using the microprocessor based step accelerometer 3 (SAM3). Setting Home and community. Participants Patients (n=23) with hematologic malignancies recovering from high-dose chemotherapy and healthy controls (n=30). Interventions Not applicable. Main Outcome Measures The intraclass correlation coefficient (ICC3,1) and its 95% confidence interval (CI), SE of measurement procedure and its 95% CI, the smallest detectable difference (SDD), the coefficient of variation (CV), and t tests for the variables total steps and peak activity. Results The day-to-day and week-to-week CVs for walking activity and peak activity were 35.17% and 13.17% and 18.61% and 6.90%, respectively. For relative reliability, the ICCs for 2 consecutive 7-day recordings including the 95% CI for total steps and peak activity were 0.90 (95% CI, 0.75 -0.98) and 0.85 (95% CI, 0.66 -0.94), respectively. The absolute reliability for total steps and peak activity including the SE of measurement procedure and the 95% CI were 564 (95% CI, + 1106) and 2.42 steps (95% CI, + 4.74), respectively, for 2 consecutive 7-day recordings. The week-to-week SDD was 1564 for total steps and 6.70 for peak activity. The 7-day mean for total step activity was 5355 for the patients with hematologic malignancies and 6364 for healthy subjects (P<0.05). Conclusions The results of this study indicate that there is good relative reliability for the assessment of 2 consecutive 7-day recordings of ambulatory walking activity, and it showed that the SDD derived from this sample may be useful in detecting changes in daily walking activity in hematologic cancer patients who are recovering from intensive medical treatment. The study also documented compromised levels of ambulatory walking activity among hematologic cancer patients recovering from highdose chemotherapy as compared with healthy controls. Key words Hematologic neoplasms; Physical activity; Rehabilitation; Technology assessment; Walking. IntroductionThe intensive medical treatment of patients with hematologic malignancies [1][2][3][4][5][6][7] is associated with numerous long-term adverse effects, including anemia, fatigue, and reduced physical exercise capacity.[8] Fatigue may compromise general activity, work, enjoyment of life, mood, walking, and relationships with others even for a length of time after medical treatment [9-11] is completed.It has been shown that patients with hematologic malignancies may benefit from physical exercise programs in terms of maintenance or even improvement in fatigue, physical activity, and fitness levels. [12][13][14] A major component of daily physical activity and the most commo...

Impaired physiological function and health-related QOL in patients before hematopoietic stem-cell transplantation

“…It may be better to commence an exercise regimen before transplantation rather than after transplantation. A previous study documented lower ambulatory walking activity levels among hematologic cancer patients than healthy subjects [32]. Decreased activity may be related to reduced physical function while undergoing HSCT.…”

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

“…Activity monitoring over a 7-day period has previously been found to result in reliable and representative measures of an individual's movements on a day-to-day basis. [17] All participants were instructed to leave the SAM3 on the ankle if they had to rest or lay down during the day and to perform their daily activities as usual. The parameters assessed by the SAM3 for this study were: (1) `average steps/day`, (2) percentage time 'with no step rate', 'at low step rate' (between 15 and 40 steps/min.…”

“…[18] The test-retest reliability, as measured by ICCs for 2 consecutive 7-day recordings including the 95% CI for total steps and peak activity, was 0.90 (95% CI, 0.75-0.98) and 0.85 (95% CI, 0.66-0.94), respectively. [17] Walking distance was assessed with the six minute walking test. The 6-minute walking test is a widely used, reliable (ICC=.98), sub-maximal exercise test that assesses the physiologic and functional status in cancer patients' [29] Self-reported physical function was assessed with the `physical function` scale (5 items) of the EORTC Core Quality-of-Life Questionnaire (EORTC QLQ-C30, version 3).…”

“…[16] Usual performance or daily activity can be reliably assessed by microprocessor-based accelerometers. [17] This relatively new approach has the potential to provide a more accurate estimate of how much patients actually walk in their day-to-day life. [14,18] Several studies have investigated the association between questionnaire-based assessments, standardized performance tests and usual performance assessments in patients with chronic diseases.…”

“…The standard 7 errors of estimate, which can be used to estimate the daily ambulatory activity from selfreported physical function and the 6-minute walking test, were large. With the improvement of prognosis in haematological malignancies, programs to improve physical health through walking and other forms of physical activity may become an increasingly important component in continuing care programs [11,17]. Ultimately, the choice of which instrument or method is the best to assess patients' level of physical activity is a function of the research question, participant burden and available resources to the researcher or the practitioner [37].…”