The weight-adjusted-waist Index (WWI), an innovative measure for assessing obesity, exhibits improved performance in estimating lean muscle and adipose tissue mass compared to both the body mass index (BMI) and waist circumference (WC). A recent finding published in BMC Musculoskeletal Disorders reveals that an increase in WWI is associated with a higher risk of osteoarthritis (OA).
Dr. Wang and colleagues conducted the population-based study using data from the National Health and Nutrition Examination Survey (NHANES). The study, involving adults aged 20 to 80 years, took place between 2011 and 2020, with the aim of examining the relationship between WWI and the prevalence of Rheumatoid arthritis (RA) and OA.
The study findings indicate a linear positive association between WWI and OA prevalence, indicating an increased risk of OA with higher WWI values. However, concerning the prevalence of RA, a non-linear association was observed, showing a strong threshold impact with a saturation value of 11.21 cm/kg. To the left of the saturation point, the two variables exhibited a positive link, but no significant association was found to the right of the saturation point, suggesting a complex non-linear relationship between the prevalence of RA and WWI.
The onset and progression of RA and OA have been linked to obesity. A study by Park et al. utilized data from 1,139,463 adults aged 50 and older obtained from the Korean National Health Insurance Service (KNHIS). They classified participants as generally obese and centrally obese based on BMI and WC, respectively. The study found that elevated BMI and larger WC increased the risk of knee OA in a dose-dependent manner. Similarly, a multi-ethnic study by Kim et al. reported that WWI indicated a positive relationship with abdominal fat mass and a negative relationship with abdominal muscle mass.
The study findings reveal a positive linear correlation between WWI and OA prevalence. On the other hand, RA prevalence showed a negative non-linear correlation, suggesting a strong threshold impact with a saturation point. To further validate these findings and better understand the relationship, additional long-term studies involving a more diverse and extensive participant pool are necessary. Such research will help establish a more comprehensive understanding of the associations between WWI, OA, and RA, contributing to improved insights for managing these conditions in clinical settings.
References
- Wang X, Xie L, Yang S. Association between weight-adjusted-waist index and the prevalence of rheumatoid arthritis and osteoarthritis: a population-based study. BMC Musculoskelet Disord. 2023 Jul 20;24:595.
- Park D, Park YM, Ko SH, Hyun KS, Choi YH, Min DU, et al. Association of general and central obesity, and their changes with risk of knee osteoarthritis: a nationwide population-based cohort study. Sci Rep. 2023 Mar 7;13(1):3796.
- Kim JY, Choi J, Vella CA, Criqui MH, Allison MA, Kim NH. Associations between Weight-Adjusted Waist Index and Abdominal Fat and Muscle Mass: Multi-Ethnic Study of Atherosclerosis. Diabetes Metab J. 2022 Sep;46(5):747–55.