Pandemic-era changes in obesity-associated disabling arthritis burden among United States adults: a repeated...

To determine whether the population burden of disabling arthritis associated with high body mass index (BMI) changed from before to during the COVID-19 pandemic in US adults.

We analyzed nationally representative adults aged ≥ 20 years from the 2019 and 2023 National Health Interview Survey. High BMI was defined as BMI ≥ 25 kg/m². The primary outcome was a prespecified disabling arthritis phenotype requiring clinician-diagnosed arthritis or a related condition, recent joint pain, severe joint pain, and arthritis-attributed activity limitation. Survey-weighted modified Poisson regression was used to estimate adjusted prevalence ratios (aPRs), test the year × BMI interaction, and derive population attributable fractions (PAFs).

Among 54,735 adults, high disabling arthritis burden affected 4.2% of adults in 2019 and 3.9% in 2023. High BMI was associated with greater disabling arthritis burden in both years, but the association weakened in 2023 relative to 2019 (aPR 1.51 vs 1.92; P for interaction = 0.016). The attenuation was concentrated among adults aged 20-44 years, whereas associations remained robust in older age groups. The estimated PAF declined from 38.4% in 2019 to 25.9% in 2023. Sensitivity analyses showed similar findings.

High BMI remained an important correlate of disabling arthritis burden, but the observed association and attributable burden were lower in 2023. Findings should be interpreted as temporal associations rather than evidence of a causal pandemic effect, and support weight management alongside disability-sensitive care and prevention strategies. Key Points • High BMI remained associated with disabling arthritis burden in US adults. • The association and attributable fraction were lower in 2023 than in 2019. • Attenuation was greatest among adults aged 20-44 years. • NHIS and GBD estimates capture related but non-equivalent burden constructs.