The Influence of Self-Efficacy on Physical Activity in Individuals With End-Stage Renal Disease

Abstract

Background and Purpose: Physical activity is significantly lower in the end-stage renal disease (ESRD) population compared with age-matched sedentary controls. Self-efficacy is a significant contributing factor to exercise behaviour in the healthy and various chronic disease populations; however, little information is available on self-efficacy and exercise in the ESRD population. The purpose of this study was to examine the relationship between self-efficacy and physical activity levels in individuals with ESRD and to determine factors which may contribute to this relationship. Participants: Patients (127 hemodialysis and 5 peritoneal dialysis) were recruited from the Kingston General Hospital renal units. Methods: Self-efficacy was measured using the Exercise Self-Efficacy Scale (ESES) and the Chronic Disease Self-Efficacy Scale (CDSES). Physical activity was measured using the Human Activity Profile (HAP). Responses on the HAP resulted in 2 scores: the maximum activity score (MAS) and the adjusted activity score (AAS). Contributing factors, such as age, co-morbidities, length on dialysis (vintage), medications, dialysis efficacy (Kt/V), albumin, prealbumin, total protein, protein catabolic rate (PCR) and hemoglobin (HgB) were collected from patient records. Results: The average MAS and AAS scores were 62.5±15.6 and 49.1± 21.0 (SD), respectively, which are substantively lower than those in the healthy population. Serum albumin was the sole contributing factor to physical activity such that AAS in those with lower levels of albumin (24-30g/L, 31-34 g/L) was less than those with higher levels of albumin (p<0.05). Both MAS and AAS were significantly lower in those with diabetes (n=66) compared to those without (n=66), as was the difference between MAS and AAS. Age and self-efficacy explained 51% of the variance in MAS. Age, self-efficacy and serum albumin level explained 59% of variance in AAS. Discussion and Conclusion: Individuals on dialysis have lower functional capability within their maximal energy ability at any age and this difference is more pronounced among those with diabetes. Physical activity was substantially influenced by an individual’s self-efficacy, age and serum albumin level. These findings indicate that self-efficacy must be taken into account and used to promote greater participation in physical activity in the ESRD population.