Table 2.

Characteristics of Participants with Biomarker Data and Baseline and Follow-Up Paired Knee Radiographs (N=364).

	Subgroups at Risk of Incident Outcome
Characteristics	Total (N=364, knees=728)	K-L Grade* (N=299, knees =542)	OST Grade† (N=203, knees=353)	JSN Grade‡ (N=260, knees=446)
Baseline Age (mean (SD))	60.4 (±9.6)	58.8 (±8.8)	58.8 (±8.6)	59.2 (±8.9)
Baseline Body Mass Index (mean kg/m2(SD))	30.4 (±7.1)	29.8 (±6.7)	28.6 (±5.5)	29.7 (±6.6)
Women, n/N (%)	231/364 (62.9)	179/299 (59.9)	113/203 (55.7)	153/260 (58.9)
African American, n/N (%)	156/364 (42.9)	115/299 (38.5)	61/203 (30.5)	99/260 (38.1)
Baseline Chronic Knee Symptoms, n/N (%)	180/362 (49.7)	127/299 (42.6)	78/202 (38.6)	113/259 (43.6)

^*K-L risk group: K-L grade of 0 or 1 in at least one knee at baseline

^†OST risk group: OST grade of 0 in at least one knee at baseline

^‡JSN risk group: JSN grade of 0 in at least one knee at baseline