Ethnic differences in the relationship between obesity and joint pain and function in a joint arthroplasty population.
OBJECTIVE
We investigated the influence of obesity on joint pain and function in Asians as compared to Caucasians with degenerative hip and knee arthritis.


METHODS
We surveyed 1983 patients (1876 Caucasians and 107 Asians) undergoing primary hip or knee replacement surgery. Relevant covariates including demographic data, body mass index (BMI), sex, comorbidities, education, and ethnicity were recorded. Pain and joint functional status were assessed at baseline and at 1-year followup with the Western Ontario and McMaster University Osteoarthritis Index (WOMAC) pain and function scores.


RESULTS
Asian patients presented for surgery at a significantly younger age and lower mean BMI, and reported greater pain and dysfunction than Caucasian patients. Multivariate linear regression modeling showed that for every level of BMI, Asian patients reported greater levels of joint pain and dysfunction. At a BMI of 30 kg/m2, this translated to a 16.6% higher WOMAC score (p < 0.001).


CONCLUSIONS
Among patients with endstage osteoarthritis, at every level of BMI, joint pain and dysfunction are greater in Asians than in Caucasians. This difference is likely mediated through both mechanical and inflammatory effects.
Gandhi
Rajiv
R
Division of Orthopedic Surgery, University of Toronto, Toronto, Canada. rajiv.gandhi@uhn.on.ca
Razak
Fahad
F
Mahomed
Nizar N
NN
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D019643:Arthroplasty, Replacement; D044466:Asian People / Q000208:ethnology*; D015992:Body Mass Index; D002170:Canada / Q000208:ethnology; D005260:Female; D006801:Humans; D007596:Joints / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D009765:Obesity / Q000150:complications / Q000208:ethnology* / Q000503:physiopathology; D015207:Osteoarthritis, Hip / Q000150:complications / Q000208:ethnology* / Q000503:physiopathology; D020370:Osteoarthritis, Knee / Q000150:complications / Q000208:ethnology* / Q000503:physiopathology; D010146:Pain / Q000208:ethnology* / Q000209:etiology / Q000503:physiopathology; D010147:Pain Measurement; D044465:White People / Q000208:ethnology*; D055815:Young Adult