ASSESSMENT OF MUSCLE STRENGTH AND ITS ASSOCIATION WITH QUALITY OF LIFE IN CHILDREN WITH CHRONIC KIDNEY DISEASE

Introduction:

Nutritional assessments for children with chronic kidney disease (CKD) often miss the crucial aspect of muscle strength, which impacts physical activity and quality of life. Hand grip strength measurement is a simple, objective method to assess muscle function. However, data on maximum voluntary contraction and muscle endurance, particularly from under-resourced countries, is limited. This study aims to evaluate hand grip strength in CKD-affected children and its link to their quality of life.

Methods:

This cross-sectional observational study involved clinically stable children with CKD stages 2-5D and transplant recipients between October 2023 and April 2024. The interim analysis of this study is presented here. Clinical data and nutritional parameters were collected. Undernutrition was defined as a body mass index (BMI) for height age below the 5th percentile according to WHO growth charts. Hand grip strength was measured using the MLT004/ST Grip Force Transducer AD Instruments, with the non-dominant hand being used (or the dominant hand in hemodialysis patients with a fistula). Maximal voluntary contraction (MVC) in kilograms was recorded three times, with constant encouragement and a minimum interval of one minute between each measurement. The best value, adjusted for forearm muscle area, was used for analysis. The rate of decline in sustained MVC was measured until it reached 50% of the initial value, and this rate (kg/s) was used as an index of static endurance. Additionally, all children were assessed for quality of life using the PedsQL version 4.0 questionnaire for ages 5-18 years.

Results:

A study involving 33 children with chronic kidney disease (CKD)—comprising 16 non-dialysis, 11 dialysis, and 6 transplant patients—aged 13.45 ± 3 years, with 66% being male, was conducted. Undernutrition was found in 6% of children in the non-dialysis group and 36% of those in the dialysis group. The mean maximum voluntary contraction (MVC) was significantly lower in the dialysis group compared to the non-dialysis group (10.6 ± 6.7 kg vs. 19.5 ± 8.2 kg, p=0.031) but was similar between the transplant and non-dialysis groups (19.3 ± 9.9 kg vs. 19.5 ± 8.2 kg, p=0.52). Ninety percent of children in the dialysis group had an MVC below the 50th percentile of the non-dialysis group. The lowest MVC recorded was 3.96 kg in a child with cystinosis undergoing dialysis. Regardless of age, gender, or BMI, the mean MVC was significantly lower in the dialysis group (β coefficient -7.54, 95% CI: -14.5 to -0.59). A similar pattern was observed in mean static endurance across the three groups (p=0.09). Overall, there was a significant positive correlation between MVC and static endurance (r=0.52, p=0.004). Both the physical and social quality of life scores for parents and children showed a modest positive correlation with MVC across the cohort.

Conclusions:

This study, conducted in an under-resourced country, highlights that muscle strength is most significantly compromised in children undergoing chronic dialysis, irrespective of undernutrition. Furthermore, muscle strength has a notable impact on the physical and social.

I have no potential conflict of interest to disclose.

I did not use generative AI and AI-assisted technologies in the writing process.