Table 1

Demographic and baseline characteristics

CharacteristicLow-dose fish oilHigh-dose fish oilp Value
Age (years): mean (SD)61 (10)61 (10)0.84
Gender (% female)4059<0.01
BMI (kg/m2): mean (SD)29 (4)29 (5)0.67
WOMAC* pain: mean (SD)15 (9)16 (9)0.35
WOMAC* function: mean (SD)49 (29)54 (34)0.28
Quality of life (AQoL-4D): mean (SD)0.77 (0.27)0.74 (0.25)0.50
NSAID use (%)34300.54
Radiographic knee OA (OARSI%)2096/101 (95%)98/101 (97%)0.47
Total OARSI joint space narrowing :mean (SD)1.7 (0.1)1.8 (0.1)0.62
Total OARSI osteophyte score: mean (SD)2.0 (0.3)2.3 (0.2)0.42
MRI Total cartilage volume (μL): mean (SD)7.46 (2.09) (n=56)6.60 (1.73) (n=60)0.02†
Any BML (%)44/55 (82%)47/55 (85%)0.61
 BML size (mm2): median (IQR)118 (209)122 (219)0.70
 CRP: median (IQR)1.5 (2.2)1.7 (2.3)0.43
Plasma omega-3 fatty acids
Plasma EPA (20:5n-3): mean (SD)1.3 (0.7) (n=95)1.5 (1.1) (n=94)0.17
Plasma DHA (22:6n-3): mean (SD)3.4 (1.0) (n=95)3.5 (1.2) (n=94)0.75
  • *Western Ontario and McMaster Universities Arthritis Index, scored on the NRS 3.1 10-point numerical scale.21 Pain scores range (0,50) and function scores range (0,170).

  • †p=0.26 after gender adjustment.

  • BMI, body mass index; BML, bone marrow lesion; CRP, C reactive protein; DHA, docosahexaenoic acid; EPA, eicosapentaenoic acid; NRS, numerical rating scale; NSAID, non-steroidal anti-inflammatory drugs; OA, osteoarthritis; OARSI, Osteoarthritis Research Society International; WOMAC, Western Ontario and McMaster Universities Arthritis Index.