Table 1

Demographic and clinical variables of the study participants

Subsample 1 (n=1253)Subsample 2 (n=2236)
Women, n (%)740 (59.1)1281 (57.3)
Age, mean (SD) years63.9 (8.8)64.5 (9.0)
Body mass index, mean (SD) kg/m229.0 (5.8)28.6 (5.5)
Knee OA (KLG≥2) (n=1695 knees), n (%)392 (23.1)NA
Erosive DIP/PIP OA* n (%)134 (10.7)221 (9.9)
 -Number of erosive OA joints, median (IQR) (0–16)3 (1–6)3 (1–5)
 -Number of non-erosive OA joints, median (IQR) (0–16)5 (3–8)5 (3–8)
Non-erosive DIP/PIP OA† n (%)461 (36.8)761 (34.0)
 -Number of non-erosive OA joints, median (IQR) (0–16)2 (1–4)2 (1–5)
Any subchondral bone attrition (n=1709 knees)‡ n (%)646 (37.8)NA
 -Number of affected knee subregions, median (IQR) (0–14)2 (1–4)
Femoral neck bone mineral density, mean (SD) g/cm2NA0.91 (0.14)
  • *One or more DIP and/or PIP joint(s) with OA (KLG≥2) and erosion in the same joint.

  • †One or more DIP and/or PIP joint(s) with OA and no erosions.

  • ‡One or more knee subregions with subchondral bone attrition grade≥1.

  • DIP, distal interphalangeal; KLG, Kellgren–Lawrence grade; NA, not applicable; OA, osteoarthritis; PIP, proximal interphalangeal.