Table 2.
Subgroup analyses.
| Subgroups | Serum Vitamin D | FBG 1 | HbA1c 1 | HOMA-IR 1 | Fasting Insulin | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| WMD 1 | 95%CI | p | WMD | 95%CI | p | WMD | 95%CI | p | SMD | 95%CI | p | SMD | 95%CI | p | ||
| Ethnicity | ||||||||||||||||
| Middle Easterners | 40.03 | (27.71, 52.34) | <0.001 | −10.43 | (−14.80, −6.06) | <0.001 | −0.36 | (−0.87, 0.15) | 0.170 | −0.65 | (−1.37, 0.08) | 0.081 | −1.48 | (−3.59, 0.63) | 0.170 | |
| Other Asians | 32.23 | (22.72, 41.73) | <0.001 | −1.83 | (−7.80, 4.15) | 0.549 | −0.18 | (−0.77, 0.42) | 0.565 | −1.59 | (−2.42, −0.76) | <0.001 | −1.80 | (−2.66, −0.95) | <0.001 | |
| Other ethnicities | 30.72 | (12.25, 49.19) | 0.001 | 1.67 | (−1.50, 4.85) | 0.301 | 0.17 | (0.00, 0.33) | 0.044 | 0.01 | (−0.45, 0.47) | 0.961 | 1.67 | (0.47, 2.87) | 0.006 | |
| BMI 1 | ||||||||||||||||
| Normal 2 | 38.20 | (27.89, 48.51) | <0.001 | −5.21 | (−11.76, 1.34) | 0.119 | 0.16 | (−0.13, 0.45) | 0.274 | −1.59 | (−2.42, −0.76) | <0.001 | −1.80 | (−2.66, −0.95) | <0.001 | |
| Overweight 2 | 33.01 | (23.94, 42.09) | <0.001 | −5.71 | (−14.09, 2.66) | 0.181 | −0.32 | (−0.70, 0.06) | 0.102 | −0.84 | (−1.78, 0.11) | 0.084 | −1.48 | (−3.59, 0.63) | 0.170 | |
| Obese 2 | 39.34 | (18.71, 59.97) | <0.001 | 0.64 | (−3.32, 4.60) | 0.751 | 0.22 | (0.05, 0.38) | 0.010 | −0.04 | (−0.38, 0.30) | 0.825 | 1.67 | (0.47, 2.87) | 0.006 | |
| Dose | ||||||||||||||||
| ≤2000 IU/day | 25.16 | (18.16, 32.16) | <0.001 | 0.35 | (−3.18, 3.89) | 0.844 | −0.21 | (−0.53, 0.11) | 0.189 | −0.50 | (−1.35, 0.35) | 0.249 | −1.80 | (−2.66, −0.95) | <0.001 | |
| >2000 IU/day | 48.45 | (29.94, 66.97) | <0.001 | −8.70 | (−12.96, −4.44) | <0.001 | 0.05 | (−0.41, 0.51) | 0.832 | −0.64 | (−1.42, 0.14) | 0.107 | −0.50 | (−2.44, 1.45) | 0.617 | |
| Duration | ||||||||||||||||
| ≤3 m | 35.51 | (18.84, 52.18) | <0.001 | −8.44 | (−12.72, −4.15) | <0.001 | −0.11 | (−0.42, 0.21) | 0.590 | −0.81 | (−1.49, −0.13) | 0.019 | ---- | ---- | ---- | |
| >3 m | 32.61 | (24.951, 40.271) | <0.001 | 2.04 | (-0.94, 5.02) | 0.180 | −0.12 | (−0.54, 0.31) | 0.509 | 0.01 | (−0.45, 0.47) | 0.961 | ---- | ---- | ---- | |
| Baseline 25(OH)D | ||||||||||||||||
| <50 nmol/L | 31.65 | (21.31, 41.99) | <0.001 | −5.77 | (−10.48, −1.05) | 0.017 | −0.11 | (−0.47, 0.26) | 0.563 | −0.81 | (−1.51, −0.11) | 0.024 | ---- | ---- | ---- | |
| 50–75 nmol/L | 48.33 | (29.46, 67.21) | <0.001 | 3.37 | (−1.81, 8.54) | 0.202 | −0.00 | (−0.14, 0.14) | 1.000 | 0.03 | (−0.67, 0.72) | 0.941 | ---- | ---- | ---- | |
| >75 nmol/L | 32.98 | (−39.64, 105.06) | 0.373 | −18.00 | (−43.24, 7.24) | 0.162 | −0.39 | (−0.78, 0.00) | 0.052 | −0.08 | (−0.55, 0.39) | 0.737 | ---- | ---- | ---- | |
| Baseline HbA1c 1 | ||||||||||||||||
| ≤7% | 45.27 | (25.39, 65.15) | <0.001 | −4.09 | (−15.44, 7.27) | 0.481 | −0.17 | (−0.86, 0.52) | 0.635 | −0.27 | (−0.65, 0.11) | 0.160 | 0.55 | (−1.49,2.59) | 0.53 | |
| >7% | 29.86 | (18.22, 41.49) | <0.001 | −3.53 | (−9.42, 2.35) | 0.240 | −0.08 | (−0.34, 0.18) | 0.548 | −0.65 | (−1.83, 0.54) | 0.286 | −2.57 | (−3.27, −1.87) | <0.001 | |
| Overall | 33.98 | (24.60, 43.37) | <0.001 | −3.59 | (−7.94, 0.76) | 0.105 | −0.11 | (−0.35, 0.13) | 0.381 | −0.58 | (−1.11, −0.05) | 0.033 | −0.83 | (−2.31, 0.64) | 0.268 | |
1 Abbreviations: WMD: weighted mean difference; SMD: standardized mean difference; FBG: fasting blood glucose; HbA1c: hemoglobin A1c; HOMA-IR: homeostatic model assessment of insulin resistance; BMI: Body mass index. 2 normal: 18.5–24.9kg/m2; overweight: 25.0–29.9 kg/m2; obese: ≥30.0 kg/m2. “----”: subgroup inapplicable to this outcome.