Association between body fat indices and pain perception: Implications for self-reported pain and pressure pain threshold in people with knee osteoarthritis

Background

Pain is the main disabling symptom in knee osteoarthritis (KOA). People with KOA are often overweight or obese, conditions associated with pain. However, the relationship between body fat indices and pain perception needs to be assessed using more accurate equipment, thereby establishing objective measures for its results.

Objectives

This study investigated the association between body fat indices and pain perception in people with KOA.

Methods

Eighty adults with KOA (58 ± 9 years, 60 % women) participated. Body fat indices were measured using Dual-Energy X-ray Absorptiometry (DEXA), and pain was assessed through pressure pain threshold (PPT) at local and remote sites. Self-reported pain was measured using the Numeric Pain Rating Scale (NPRS) and the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC). Multiple linear regression models, adjusted for age and sex, were used to analyze these associations.

Results

Higher body fat percentage (% body fat) was associated with lower PPTs (β = 1.7; 95 % CI: 1.2–4.8) and higher WOMAC scores (β = 0.3; 95 % CI: 1.1–2.7); fat mass index (FMI) showed similar trends. Visceral adipose tissue (VAT) was only significantly associated with NPRS (β = 45.4; 95 % CI: 13.4–77.5).

Conclusion

Body fat mass is a key factor in pain perception in people with KOA. These findings underscore the importance of detailed body fat assessments in this population, which aid in developing more precise and personalized therapeutic interventions for managing chronic pain.