Table 3.
Subgroup analysis
| Arthritis pain of patients with OA | Joint function of patients with OA | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Study characteristics | Datasets number | SMD (95% CI) | I2 (%) | P1 | P2 | Datasets number | SMD (95% CI) | I2 (%) | P1 | P2 |
| Scale | ||||||||||
| WOMAC | 5 | − 0.23 [− 0.45, − 0.02] | 67 | 0.03 | 5 | − 0.19 [− 0.36, − 0.02] | 49 | 0.03 | ||
| Others | 4 | − 0.40 [− 0.67, − 0.13] | 19 | 0.003 | 0.33 | 3 | − 0.35 [− 0.65, − 0.05] | 0 | 0.02 | 0.34 |
| Mean age | ||||||||||
| < 65 years | 5 | − 0.40 [− 0.67, − 0.13] | 60 | 0.004 | 5 | − 0.29 [− 0.50, − 0.08] | 31 | 0.006 | ||
| ≥ 65 years | 4 | − 0.09 [− 0.19, 0.02] | 0 | 0.10 | 0.03 | 3 | − 0.12 [− 0.23, − 0.01] | 0 | 0.03 | 0.15 |
| Dose of n− 3 PUFA | ||||||||||
| < 1000 mg/d | 5 | − 0.11 [− 0.21, − 0.01] | 0 | 0.02 | 5 | − 0.14 [− 0.24, − 0.05] | 0 | 0.004 | ||
| ≥ 1000 mg/d | 4 | − 0.49 [− 0.86, − 0.11] | 69 | 0.01 | 0.09 | 3 | − 0.37 [− 0.80, 0.06] | 65 | 0.09 | 0.31 |
| Dose of EPA | ||||||||||
| < 500 mg/d | 4 | − 0.08 [− 0.19, 0.02] | 0 | 0.12 | 3 | − 0.11 [− 0.22, − 0.00] | 0 | 0.04 | ||
| ≥ 500 mg/d | 5 | − 0.39 [− 0.65, − 0.14] | 60 | 0.003 | 0.08 | 5 | − 0.31 [− 0.51, − 0.10] | 33 | 0.003 | 0.09 |
| Dose of DHA (mg/d) | ||||||||||
| < 500 mg/d | 5 | − 0.11 [− 0.21, − 0.01] | 0 | 0.02 | 5 | − 0.14 [− 0.24, − 0.05] | 0 | 0.004 | ||
| ≥ 500 mg/d | 4 | − 0.49 [− 0.86, − 0.11] | 69 | 0.01 | 0.09 | 3 | − 0.37 [− 0.80, 0.06] | 65 | 0.09 | 0.31 |
| Follow− up duration | ||||||||||
| < 6 months | 4 | − 0.39 [− 0.70, − 0.09] | 38 | 0.01 | 3 | − 0.33 [− 0.77, 0.11] | 60 | 0.15 | ||
| ≥ 6 months | 5 | − 0.23 [− 0.44, − 0.03] | 65 | 0.03 | 0.39 | 5 | − 0.14 [− 0.24, − 0.05] | 0 | 0.002 | 0.42 |
P1 p values for subgroup effect; P2 p values for subgroup difference; OA osteoarthritis; SMD standardized mean difference; CI confidence interval; n-3 PUFA omega-3 polyunsaturated fatty acids; EPA eicosapentaenoic acid; DHA docosahexanoic acid; WOMAC Western Ontario-McMaster University Osteoarthritis Index