title: Differences in radiographic features of knee osteoarthritis in African-Americans and Caucasians: the Johnston county osteoarthritis project.
abstract: OBJECTIVE
  To examine racial differences in tibiofemoral joint (TFJ) and patellofemoral joint (PFJ) radiographic osteoarthritis in African-American (AA) and Caucasian men and women.
  
  
  METHODS
  Multiple logistic regression was used to evaluate cross-sectional associations between race and tibiofemoral osteoarthritis (TF-OA) and the presence, severity and location of individual radiographic features of tibiofemoral joint osteoarthritis [TFJ-OA] (osteophytes, joint space narrowing [JSN], sclerosis and cysts) and patellofemoral joint osteoarthritis (PFJ-OA) (osteophytes, JSN and sclerosis), using data from the Johnston County Osteoarthritis Project. Proportional odds ratios (POR) assessed severity of TF-OA, TFJ and PFJ osteophytes, and JSN, adjusting for confounders. Generalized estimating equations accounted for auto-correlation of knees.
  
  
  RESULTS
  Among 3187 participants (32.5% AAs; 62% women; mean age 62 years), 6300 TFJ and 1957 PFJ were included. Compared to Caucasians, AA men were more likely to have TF-OA (adjusted odds ratio [aOR]=1.36; 95% CI, 1.00-1.86); tri-compartmental TFJ and PFJ osteophytes (aOR=3.06; 95%CI=1.96-4.78), and TFJ and PFJ sclerosis. AA women were more likely than Caucasian to have medial TFJ and tri-compartmental osteophytes (aOR=2.13; 1.55-2.94), and lateral TFJ sclerosis. AAs had more severe TF-OA than Caucasians (adjusted cumulative odds ratio [aPOR]=2.08; 95% CI, 1.19-3.64 for men; aPOR=1.56; 95% CI, 1.06-2.29 for women) and were more likely to have lateral TFJ JSN.
  
  
  CONCLUSIONS
  Compared to Caucasians, AAs were more likely to have more severe TF-OA; tri-compartmental disease; and lateral JSN. Further research to clarify the discrepancy between radiographic features in OA among races appears warranted.
authors.affiliation: Thurston Arthritis Research Center, University of North Carolina at Chapel Hill, NC 27599-7280, USA.
authors.forename: L
authors.initials: L
authors.lastname: Braga
authors.forename: J B
authors.initials: JB
authors.lastname: Renner
authors.forename: T A
authors.initials: TA
authors.lastname: Schwartz
authors.forename: J
authors.initials: J
authors.lastname: Woodard
authors.forename: C G
authors.initials: CG
authors.lastname: Helmick
authors.forename: M C
authors.initials: MC
authors.lastname: Hochberg
authors.forename: J M
authors.initials: JM
authors.lastname: Jordan
mesh_terms: D001741:Black or African American / Q000208:ethnology; D015992:Body Mass Index; D015519:Bone Density; D005260:Female; D006801:Humans; D007719:Knee Joint / Q000000981:diagnostic imaging*; D008297:Male; D008875:Middle Aged; D020370:Osteoarthritis, Knee / Q000000981:diagnostic imaging* / Q000208:ethnology; D054850:Osteophyte / Q000000981:diagnostic imaging* / Q000208:ethnology; D015995:Prevalence; D011859:Radiography; D012016:Reference Values; D012307:Risk Factors; D012720:Severity of Illness Index; D017678:Sex Distribution; D044465:White People / Q000208:ethnology