Obesity in early childhood linked to higher rates of musculoskeletal consultations

In a recent study published in Archives of Disease in Childhood, a group of researchers evaluated the incidence of musculoskeletal consultations in children with obesity in a primary care setting.

Study: Are children living with obesity more likely to experience musculoskeletal symptoms during childhood? A linked longitudinal cohort study using primary care records. Image Credit: New Africa/Shutterstock.com

Background 

Worldwide, one in three adults and a similar proportion of children in the United Kingdom (UK) experience musculoskeletal problems, which cause pain and disability and affect mental health.

The increasing prevalence of obesity is worsening these issues, as excess weight significantly stresses the body’s joints, leading to conditions like back pain, chronic pain, and slipped capital femoral epiphysis (SCFE).

Earlier research suggested a link between being overweight and an increased risk of musculoskeletal issues in children, but the evidence was mostly cross-sectional and of moderate to low quality.

Recent longitudinal studies also support this association, yet they are few and of moderate quality, with inconsistent accounting for confounding variables. This underscores the urgent need for further research to clarify the causal relationship between obesity and musculoskeletal symptoms in children.

About the study 

The present study included 123,836 (96.3%) participants from the National Child Measurement Programme (NCMP) across four northeast London local authorities, with their records linked to primary care using pseudonymized National Health Service (NHS) numbers.

The NCMP involves measuring the height and weight of children in their first and last years of primary school to monitor public health trends.

Data sharing agreements facilitated the use of NCMP data from 2013/14 to 2018/19, alongside pseudonymized primary care data from the Discovery Data Service for 285 general practitioners (GPs).

This study focused on identifying musculoskeletal consultations among these children, excluding any prior to their NCMP measurement. 

Musculoskeletal consultations were determined through specific clinical codes, with the primary outcome being the presence or absence of at least one GP consultation for a musculoskeletal issue following the NCMP measurement.

Children’s body mass index (BMI) was adjusted for ethnicity and categorized into underweight, healthy weight, overweight, or obese according to UK standards.

Ethnicity, derived from NCMP records or, when missing, from electronic health records, and area-level deprivation were considered as confounding factors.

Statistical analysis involved estimating musculoskeletal consultation proportions and incidence rates, with Kaplan-Meier failure functions and Cox’s proportional hazards regression adjusting for confounders, including the academic year of NCMP participation and local authority.

The study also explored interactions between sex and school year of NCMP measurement. The analysis was conducted using Stata, adhering to rigorous data management and statistical standards to ensure the integrity of the findings.

Study results 

The study scrutinized a significant population from the NCMP, comprising 63,418 children in Reception (50.9% boys) and 55,364 children in Year 6 (50.8% boys).

Predominantly, these children hailed from the most deprived areas and were of Black or minority ethnic backgrounds, with a small fraction (less than 1%) excluded due to missing ethnic data.

Notably, obesity rates were higher in older children, with 19.9% of Year 6 boys and 14.4% of Year 6 girls living with obesity, compared to 8.9% of Reception boys and 7.1% of Reception girls.

The analysis revealed variations in musculoskeletal consultations by weight status. In younger children, girls with obesity were more likely to seek musculoskeletal consultations than their healthy-weight counterparts, a trend not observed in boys.

Among the older cohort, both girls with obesity and boys classified as underweight showed differences in consultation rates compared to their healthy-weight peers.

The most frequent musculoskeletal issues involved knee and back pain, with a higher prevalence of back pain reported in the Year 6 cohort compared to Reception children.

Over the follow-up period, which ranged from two to eight years, the first musculoskeletal consultation typically occurred within two to three years after the NCMP measurements.

Incidence rates of consultations varied, with girls living with obesity in both cohorts showing higher rates compared to those with a healthy weight. Interestingly, underweight Year 6 boys had a lower incidence rate than their counterparts.

Cumulative incidence analysis highlighted a higher likelihood of musculoskeletal consultations among Reception girls with obesity, although the small sample size introduced uncertainty.

The incidence was notably lower for Year 6 boys classified as underweight, with the confidence interval distinctly not overlapping with other weight categories.

The study’s findings underscore the heightened risk of musculoskeletal consultations among children with obesity, particularly girls, across different age groups.

The multivariable analysis, adjusting for various factors, confirmed this increased risk for overweight and obese girls in Reception and Year 6, with underweight boys in Year 6 showing a reduced likelihood of consultations.