A Comprehensive Exercise (COMEX) Intervention to Optimize Exercise Participation for Improving Patient-Centered Outcomes and Physical Functioning in Patients Receiving Hemodialysis: Development and Pilot Testing

Abstract

Rationale & objective: To address the need for an intradialytic exercise program that is easily delivered in clinical setting, engaging and scalable, we developed a novel COMprehensive EXercise (COMEX) program based on input from patients receiving hemodialysis (HD), dialysis staff members and nephrologists. The objective of this study was to determine the feasibility, safety, and acceptance of COMEX during HD.

Study design: Single-arm prospective pilot feasibility study.

Setting & participants: Seventeen patients receiving in-center HD.

Intervention: Three-month participation in the COMEX program, which included video-based dialysis chair exercises (aerobic and resistance) integrated with educational and motivational components.

Outcomes: Data on recruitment, adherence, safety and acceptability were collected. Additional assessments were performed to evaluate changes in physical functioning, patient-reported symptoms, and objectively measured sleep and physical activity. We also examined the feasibility of obtaining skeletal muscle biopsies and blood samples to explore molecular mechanisms of muscle atrophy and to assess platelet mitochondrial function and adaptation to exercise during HD.

Results: Thirteen of the 17 (76%) participants completed the 3-month intervention. The mean participant age was 63.6 ± 15.1 years. In total, 46% of participants were males, and 55% were White. The mean body mass index was 38.7 ± 11.6 kg/m². There were no reported adverse effects, and the adherence rate to exercise sessions was high with 88% of the sessions completed. Patient satisfaction was high, as 100% of the patients would recommend the program to other dialysis patients. It was feasible to collect data on physical functioning, patient-reported symptoms, and objective sleep and physical activity and to obtain muscle biopsies and blood samples.

Limitations: Small sample size, lack of an onsite exercise professional, and technological issues with telemedicine behavioral motivation.

Conclusions: The COMEX intradialytic exercise intervention is safe and acceptable to patients, and outcome measures were feasible to obtain. Future studies should consider including exercise professionals to facilitate progression through a personalized exercise protocol.

Funding source: This work is supported by pilot award from P30 DK079307 (PI, Jhamb).

Trial registration: ClinicalTrials.gov, NCT03055299.

Plain-language summary: We tested a new COMprehensive EXercise (COMEX) program to deliver exercise during dialysis. This 3-month program included video-based dialysis chair exercises (aerobic and resistance) integrated with educational and motivational components. Our study shows COMEX was feasible, had high satisfaction and adherence, and was safe. It was feasible to collect data on physical functioning, patient-reported symptoms, and objective sleep and physical activity and to obtain muscle biopsies and blood samples. Future studies should consider including exercise professionals to facilitate progression through a personalized exercise protocol.

Keywords: depression; exercise; fatigue; hemodialysis patients; pain; patient-centered outcomes; symptoms.

Graphical abstract

Figure 1

Participant recruitment in COMEX study. Abbreviations: PCP, primary care physician; PI, principal investigator; PT, physical therapy.

Figure 2

Change in objective physical function tests with the COMEX intervention. Abbreviations: SPPB, Short Performance Physical Battery (composite score range 0-12; lower score indicates worse physical function), 6MWT: Six-Minute Walk Test (shorter distance suggests lower aerobic capacity).

Figure 3

Changes in patient-reported symptoms with the COMEX intervention. Abbreviations: PSQI, Pittsburgh Sleep Quality Index (possible score range 0-21, higher score indicates worse sleep quality); BDI-II, Beck Depression Inventory Second Edition (possible score range 0-63, higher score indicates worse depression); FACIT-F, Functional Assessment of Chronic Illness Therapy Fatigue (possible score range 0-52, lower score indicates worse fatigue); MOS BPI, Medical Outcomes Survey Bodily Pain Index (possible score range 0-100, lower score indicates more severe or limiting pain); MOS PCS, Medical Outcomes Survey Physical Component Score (possible score range 0-100, lower score indicates worse composite of factors contributing to physical health); MOS MCS, Medical Outcomes Survey Mental Component Score (possible score range 0-100, lower score indicates worse composite of factors contributing to overall mental health).