The Effect of Intradialytic Eye Exercise in Hemodialysis Patients

Official title

The Effect of Intradialytic Eye Exercise on Physical Function, Balance, and Fall Risk in Hemodialysis Patients: A Randomized Pilot Trial

Overview

This pilot randomized trial will evaluate whether a structured intradialytic eye-exercise program can be delivered safely and consistently during maintenance hemodialysis and whether it shows preliminary promise for improving physical function, balance, and fall-related concern. The study is needed because hemodialysis patients commonly experience impaired physical performance, reduced balance, and fear of falling, and these problems are associated with higher fall risk; at the same time, supervised exercise during dialysis is increasingly viewed as a practical way to reach this medically complex and often sedentary population. Eye-movement and gaze-stability training has also shown benefit for balance- and fall-related outcomes in older adults and stroke survivors, but its feasibility and potential value during dialysis sessions remain uncertain.

Detailed description

Patients receiving maintenance hemodialysis often live with deconditioning, reduced mobility, impaired balance, and substantial fall-related concern, all of which can undermine independence and daily functioning. Recent hemodialysis research has shown that poorer physical performance and greater fear of falling are strongly associated with fall risk, while recent reviews indicate that falls in this population are common and influenced by multiple interacting factors, including physical decline and reduced activity. Supervised intradialytic exercise is a logical delivery model because it can be integrated into the dialysis session, monitored directly by clinical staff, and implemented with acceptable safety and adherence in appropriately screened patients. In parallel, eye-focused training that targets oculomotor control, gaze stability, and visual-motor coordination has improved balance, gait, and fall-related confidence in other populations, including stroke survivors and older adults, suggesting a plausible mechanism for helping patients whose balance and mobility are compromised by inactivity, frailty, and treatment-related instability. However, evidence for this approach in hemodialysis remains limited, and it is not yet known whether such a program can be delivered reliably within the practical constraints of the dialysis unit without interfering with treatment. A pilot randomized trial is therefore warranted to determine feasibility, tolerability, and safety, to identify workflow barriers, and to estimate whether the intervention shows enough promise to justify a larger definitive efficacy trial.

Interventions

• Behavioral Intradialytic Eye Exercise
  The participants in the study group will perform the eye exercise program while seated during hemodialysis treatment. The exercises will be administered face-to-face in the dialysis unit (not via teleconference). Each session will last 15 to 20 minutes and will be performed during clinically stable periods of dialysis. The program includes vestibulo-ocular reflex (VOR x1 and adaptation), saccadic eye movements (rapid shifts between targets), smooth pursuit (tracking moving targets), vergence (ne

Primary outcome measures

• Recruitment rate [Time frame: Baseline to 12 weeks]
• Retention rate [Time frame: Baseline to 12 weeks]
• Adherence rate [Time frame: Baseline to 12 weeks]
• Safety and tolerability [Time frame: Baseline to 12 weeks]

Secondary outcome measures (5)

• Physical function (SPPB total score) [Time frame: Baseline and 12 weeks]
• Functional mobility (Timed Up and Go test) [Time frame: Baseline and 12 weeks]
• Lower-limb functional strength (30-second sit-to-stand) [Time frame: Baseline and 12 weeks]
• Balance (Berg Balance Scale) [Time frame: Baseline and 12 weeks]
• Fall risk / fear of falling (Falls Efficacy Scale-International) [Time frame: Baseline and 12 weeks]

Eligibility criteria

Inclusion criteria

• Adults ≥18 years receiving maintenance in-center hemodialysis
• Clinically stable for brief seated intradialytic intervention
• Able to understand and follow eye-exercise instructions
• Able to provide informed consent
• Able to sit upright independently during dialysis
• Able to complete repeated outcome assessments
• Able to communicate discomfort or adverse symptoms
• Usual corrective lenses permitted if needed for visual clarity

Exclusion criteria

• Unstable cardiac conditions (e.g., unstable angina, recent myocardial infarction, decompensated heart failure, uncontrolled arrhythmia)
• Active infection or acute medical illness
• Hemodynamic instability
• Significant cognitive or communication impairment preventing instruction-following
• Severe uncorrected visual impairment or active ocular disease
• Recent major ophthalmologic surgery
• Severe musculoskeletal or neurologic limitations preventing participation or testing
• Any condition deemed unsafe for intradialytic exercise by the treating physician or nephrologist

Criteria are shown verbatim from the registry (in English). Final eligibility is always assessed by the study center.

Healthy volunteers: No

Study design

Allocation

Randomized

Model

Parallel assignment

Masking

Single blind

Primary purpose

Supportive care

Study locations

Iran · 1 center

• Pardis specialized wellness institute — Isfahan

Publications

• Son CH, Sim GW, Kim K. A Study on the Effects of a Self-Administered Eye Exercise Program on the Balance and Gait Ability of Chronic Stroke Patients: A Randomized Controlled Trial. J Pers Med. 2024 Jun 2;14(6):595. doi: 10.3390/jpm14060595. PMID 38929816
• Mueangson O, Keawmai W, Pabbumnan R, Chukaithai A, Thongdonmuean P, Vongvaivanichakul P. The Effects of Eye Exercises on Eye-Hand Coordination, Cognitive Functions and Balance Ability of the Elderly: A Randomized Controlled Trial. Int J Environ Res Public Health. 2025 Oct 14;22(10):1564. doi: 10.3390/ijerph22101564. PMID 41154968
• Asahina Y, Sakaguchi Y, Kajimoto S, Hattori K, Oka T, Kaimori JY, Kashihara N, Isaka Y. A Randomized Controlled Trial of Whole-Body Vibration on Gait Ability and Balance among Older Hemodialysis Patients. Clin J Am Soc Nephrol. 2023 Jan 1;18(1):84-90. doi: 10.2215/CJN.0000000000000018. PMID 36719160
• Finco MG, Najafi B, Zhou H, Hamad A, Ibrahim R, Al-Ali F. Game-based intradialytic non-weight-bearing exercise training on gait speed and balance in older adults with diabetes: a single-blind randomized controlled trial. Sci Rep. 2023 Aug 30;13(1):14225. doi: 10.1038/s41598-023-41290-3. PMID 37648695
• Yabe, H., Yamaguchi, T., Kono, K. et al. Effect of intradialytic exercise on fall occurrences in older patients undergoing hemodialysis: a single-center non-randomized study. Ren Replace Ther 9, 48 (2023). https://doi.org/10.1186/s41100-023-00503-1
• Gute L, Zimbudzi E. Interventions to reduce falls among dialysis patients: a systematic review. BMC Nephrol. 2023 Dec 21;24(1):382. doi: 10.1186/s12882-023-03408-7. PMID 38129770
• Hu H, Wu C, Kwok JYY, Ho MH, Chau PH, Lok KYW, Choi EPH. Effects of Different Exercises on Physical Function, Dialysis Adequacy, and Health-Related Quality of Life in Maintenance Hemodialysis Patients: A Systematic Review and Network Meta-Analysis. Am J Nephrol. 2023;54(9-10):379-390. doi: 10.1159/000532109. Epub 2023 Aug 3. PMID 37536298
• Bogataj S, Pajek M, Kren A, Kurnik Mesaric K, Pajek J. Randomized Controlled Trial of Intradialytic Cognitive and Physical Training to Enhance Functional Capacity. Kidney Int Rep. 2024 Apr 15;9(7):2028-2036. doi: 10.1016/j.ekir.2024.04.029. eCollection 2024 Jul. PMID 39081752

Identifiers

NCT: NCT07591714 · PA26HD-2-01

Primary sources (government registries)

• ClinicalTrials.gov (US NIH)

View this study on ClinicalTrials.gov ↗