Reference Values for the Six Minute Walk Test in Children with Juvenile Idiopathic Arthritis

Abstract

Aims

To (1) describe six-minute walk test (6MWT) reference values for children with Juvenile Idiopathic Arthritis (JIA) and (2) explore predictors of 6MWT distance. A secondary objective was to determine how 6MWT distances of children with JIA compare to those of children without JIA reported in the literature.

Methods

Demographic, clinical, height, weight and 6MWT data were extracted from clinical records of 120 children with JIA (70.8% female, $\text{mean age}=$12.4 ± 3.2 years) who attended a follow-up rheumatology clinic. A total of 272 6MWTs were included in the analyses. Linear mixed effects modeling was used to determine the relationship between predictive variables and 6MWT distance. 6MWT distances were compared to predicted values using published equations for estimating 6MWT distances in children without JIA.

Results

Height, weight, and age were predictive of 6MWT distance (R² = 0.62). Mean 6MWT distances for children with JIA were lower than those reported for children without JIA (p < 0.001). Mean 6MWT distance was 84% and 78% of predicted values for children without JIA.

Conclusion

The reference values and associated predictive model have application for assessing exercise capacity in children with JIA.

KEYWORDS:

• Exercise
• juvenile inflammatory arthritis
• rehabilitation
• six-minute walk test

Acknowledgements

The authors would like to express our gratitude to Shazmin Giga and Lori Wolfe who recruited participants and collected the data for this study. The authors would also like to express their appreciation to the participants and their families for their contributions to this research.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

Funding for this project was provided by the Glenrose Rehabilitation Hospital Foundation. Dr. Pritchard was supported by the Women and Children’s Health Research Institute (WCHRI) through the generous support of the Stollery Children’s Hospital Foundation, the Canadian Child Health Clinician Scientist Training Program, and Alberta PolicyWise for Children and Families.

Notes on contributors

Qaasim Mian

Dr. Qaasim Mian is a Senior Pediatric resident in the Department of Pediatrics, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, Alberta, Canada.

Dax G. Rumsey

Dr. Dax G. Rumsey is a Pediatric Rheumatologist and Associate Professor in the Department of Pediatrics, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, Alberta, Canada.

Olaf Verschuren

Dr. Olaf Verschuren is a Pediatric Physical Therapist and Senior Researcher at the Centre of Excellence for Rehabilitation Medicine, UMC Utrecht Brain Center, University Medical Center Utrecht, Utrecht University and De Hoogstraat Rehabilitation, Utrecht, the Netherlands.

Elham K. Moez

Dr. Elham K. Moez is currently pursuing a Postdoctoral fellowship in Molecular Epidemiology of Cancer at Lunenfeld-Tanenbaum Research Institute. At the time of writing, she was a Ph.D. candidate in Epidemiology at the University of Alberta, Canada. Her research interest is to develop and apply efficient statistical methods to analyze various health research data with complex structure.

Michelle Roy

Michelle Roy is a Pediatric Physical Therapist at the Glenrose Rehabilitation Hospital in Edmonton, Alberta, Canada.

Cara Kaup

Cara Kaup is a Pediatric Physical Therapist at the Glenrose Rehabilitation Hospital, Edmonton, Alberta, Canada.

Lesley Pritchard

Dr. Lesley Pritchard is a Pediatric Physical Therapist and Associate Professor in the Department of Physical Therapy, Faculty of Rehabilitation Medicine, University of Alberta, Edmonton, Alberta, Canada.