Pedometers as a means to increase spontaneous physical activity in chronic hemodialysis patients

Background: Pedometers are simple devices which measure spontaneous physical activity. In nonrenal disease populations, pedometers were successfully used to encourage patients to increase their habitual physical activity through self-monitoring of its intensity. Our aim was to investigate how an awareness of using pedometers helps in increasing daily spontaneous physical activity in patients on hemodialysis. Methods: We studied 33 hemodialysis patients (16 women, 17 men; mean age 58.3 +/- 10.1 years; mean dialysis vintage 41.4 +/- 28.6 months). Daily walking activity was measured by pedometers 7 times over 4 months during 5 midweek interdialysis periods and 2 dialysis-free weekends. During the study, patients recorded their activities and pedometer readings. Blood count, serum albumin, electrolytes, lipids, C-reactive protein (CRP), interdialytic weight gain and erythropoiesis-stimulating agent dosages were also measured. Body composition was estimated with multifrequency phase-sensitive bioimpedance. The patients also filled in the SF-36 questionnaire. Results: Total number of steps counted between 2 midweek dialysis sessions increased from a mean 9,337 +/- 5,317 to 11,921 +/- 5,909 (p=0.001). Number of steps during dialysis-free days increased, from 3,766 +/- 1,963 to 4,978 +/- 2,495 (p=0.0005). Total number of steps between midweek dialysis and dialysis after dialysis- free weekend break tended to increase from 20,974 +/- 10,696 to 22,080 +/- 11,631 (p=0.06). At study end, the number of steps taken during weekend days was greater than during between midweek dialysis sessions. Bioimpedance did not reveal significant changes of body composition. The patients had similar scores on physical functioning, general health and mental health perception and total SF-36 at the end of the study. Conclusion: Pedometers could serve as a simple means to increase spontaneous physical activity in patients on chronic hemodialysis.