Table 3.
Subgroup analyses of L-carnitine on glycemic indices in adults.
| Number of effect sizes | WMD (95%CI) | P-value | Heterogeneity | |||
|---|---|---|---|---|---|---|
| P heterogeneity | I 2 | P between sub-groups | ||||
| Subgroup analyses of carnitine on serum FBG (mg/dl) | ||||||
| Overall effect | 42 | −3.22 (−5.21, −1.23) | 0.002 | < 0.001 | 88.6% | |
| Baseline FBG (mg/dl) | ||||||
| < 100 | 16 | −0.40 (−2.94, 2.13) | 0.755 | < 0.001 | 85.6% | 0.005 |
| ≥100 | 26 | −5.91 (−8.84, −2.99) | < 0.001 | < 0.001 | 88.6% | |
| Trial duration (week) | ||||||
| < 12 | 17 | 0.01 (−1.68, 1.69) | 0.997 | 0.028 | 43.7% | 0.001 |
| ≥12 | 25 | −5.81 (−8.73, −2.88) | < 0.001 | < 0.001 | 92.5% | |
| Intervention dose (g/day) | ||||||
| < 2 | 15 | −1.13 (−4.05, 1.79) | 0.448 | < 0.001 | 85.5% | 0.077 |
| ≥2 | 27 | −4.73 (−7.45, −2.01) | 0.001 | < 0.001 | 89.5% | |
| Baseline BMI (kg/m2) | ||||||
| Normal (18.5–24.9) | 8 | 0.92 (−1.96, 3.82) | 0.529 | 0.071 | 46.4% | 0.029 |
| Overweight (25–29.9) | 22 | −4.35 (−7.76, −0.94) | 0.018 | < 0.001 | 90.2% | |
| Obese (>30) | 11 | −4.83 (−8.44, −1.21) | 0.021 | < 0.001 | 91.9% | |
| Health status | ||||||
| Diaberic | 17 | −6.55 (−9.92, −3.18) | < 0.001 | < 0.001 | 90.5% | 0.017 |
| Non-diabetic | 25 | −1.35 (−3.95, 1.24) | 0.307 | < 0.001 | 86.3% | |
| Subgroup analyses of carnitine on serum Insulin (pmol/l) | ||||||
| Overall effect | 21 | −1.37 (−3.14, 0.39) | 0.128 | < 0.001 | 96.7% | |
| Trial duration (week) | ||||||
| < 12 | 9 | −0.01 (−1.43, 1.41) | 0.988 | 0.033 | 52.1% | 0.083 |
| ≥12 | 12 | −2.33 (−4.53, −0.13) | 0.038 | < 0.001 | 97.9% | |
| Intervention dose (g/day) | ||||||
| < 2 | 8 | −0.39 (−5.51, 4.71) | 0.879 | < 0.001 | 98.5% | 0.678 |
| ≥2 | 13 | −1.50 (−2.53, −0.47) | 0.004 | < 0.001 | 86.3% | |
| Baseline BMI (kg/m2) | ||||||
| Overweight (25–29.9) | 13 | −0.05 (−1.33, 1.22) | 0.932 | < 0.001 | 73.2% | 0.011 |
| Obese (>30) | 7 | −3.39 (−6.32, −0.46) | 0.023 | < 0.001 | 98.2% | |
| Health status | ||||||
| Diaberic | 9 | −1.15 (2.35, 0.05) | 0.061 | < 0.001 | 87.0% | 0.813 |
| Non-diabetic | 12 | −1.57 (−4.84, 1.70) | 0.346 | < 0.001 | 97.9 | |
| Subgroup analyses of carnitine on serum HbA1c (%) | ||||||
| Overall effect | 21 | −0.27 (−0.47, −0.07) | 0.007 | < 0.001 | 90.1% | |
| Trial duration (week) | ||||||
| < 12 | 6 | 0.04 (−0.05, 0.14) | 0.400 | 0.839 | 0.0% | 0.001 |
| ≥12 | 15 | −0.40 (−0.65, −0.14) | 0.002 | < 0.001 | 92.1% | |
| Intervention dose (g/day) | ||||||
| < 2 | 5 | −0.01 (−0.11, 0.08) | 0.772 | 0.813 | 0.0% | 0.011 |
| ≥2 | 16 | −0.38 (−0.64, −0.11) | 0.005 | < 0.001 | 92.0% | |
| Baseline BMI (kg/m2) | ||||||
| Overweight (25–29.9) | 15 | −0.08 (−0.17, 0.01) | 0.091 | 0.168 | 25.4% | 0.064 |
| Obese (>30) | 5 | −0.75 (−1.37, −0.13) | 0.018 | < 0.001 | 96.4% | |
| Health status | ||||||
| Diaberic | 15 | −0.41 (−0.69, −0.13) | 0.004 | < 0.001 | 92.5% | 0.010 |
| Non-diabetic | 6 | −0.02 (−0.11, 0.07) | 0.634 | 0.833 | 0.0% | |
| Subgroup analyses of carnitine on HOMA-IR | ||||||
| Overall effect | 18 | −0.73 (−1.21, −0.25) | 0.003 | < 0.001 | 98.2% | |
| Trial duration (week) | ||||||
| < 12 | 7 | −0.26 (−0.80, 0.27) | 0.329 | < 0.001 | 77.3% | 0.075 |
| ≥12 | 11 | −1.00 (−1.60, −0.39) | 0.001 | < 0.001 | 98.8% | |
| Intervention dose (g/day) | ||||||
| < 2 | 6 | −0.44 (−2.21, 1.32) | 0.623 | < 0.001 | 99.2% | 0.709 |
| ≥2 | 12 | −0.78 (−1.11, −0.45) | < 0.001 | < 0.001 | 89.5% | |
| Baseline BMI (kg/m2) | ||||||
| Overweight (25–29.9) | 10 | −0.15 (−0.77, 0.46) | 0.618 | < 0.001 | 96.8% | 0.044 |
| Obese (>30) | 18 | −1.28 (−2.19, −0.37) | 0.006 | < 0.001 | 98.1% | |
| Health status | ||||||
| Diabetic | 8 | −0.73 (−1.34, −0.11) | 0.020 | < 0.001 | 89.7% | 0.983 |
| Non diabetic | 10 | −0.74 (−1.39, −0.08) | 0.027 | < 0.001 | 98.9% | |
BMI, body mass index; CI, confidence interval; FBG, fasting blood glucose; HbA1c, hemoglobin A1c; HOMA-IR, homeostatic model assessment for insulin resistance; WMD, weighted mean differences.