Table 1.
Characteristics of the studies included in the meta-analysis.
| Study Characteristics | Population Characteristics | Intervention Characteristics | Outcome | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| First Author (Year) | Country | n (Female) | Age (Years) Mean ± SD | BMI (kg/m2) Mean ± SD |
Disease Severity (EDSS) Mean ± SD | MS Type | Disease Duration (Years) Mean ± SD | 25(OH)D Baseline Level (ng/mL) | Duration/w | Frequency(x/Week) | Vit D Dose | Comparator | Adherence | Side Effects | Fatigue Scale |
| Achiron et al., (2014) [35] | Israel | 158 (118) | 41.1 ± 9.2 | NR | 2.9 ± 2.6 | RR: 91.7% | 6.2 ± 5.5 | NR | 6 months | 7 | 1 mcg | Placebo | IG: 90% | IG: headache and dizziness | FIS; MFIS |
| CG: 91% | CG: abdominal pain | ||||||||||||||
| Bahmani et al., (2022) [36] | Irán | 38 (38) | AT + VitD: 27.70 ± 2.68 | NR | 3–5 (range) | NR | NR | AT + VitD: 25.80 ± 1.81 | 8 | 1 | 50,000 units | AT Placebo (CG) |
AT + VitD: 100% | NR | MFIS |
| AT: 26.77 ± 2.27 | AT: 26.55 ± 1.50 | AT: 90% | |||||||||||||
| VitD: 25.44 ± 2.29 | VitD: 26.44 ± 1.42 | VitD: 90% | |||||||||||||
| CG: 28.11 ± 3.62 | CG: 27.20 ± 3.45 | CG: 100% | |||||||||||||
| Kampman et al., (2012) [37] | Norway | 68 (48) | IG: 40 (21–50) ** | IG: 28 (21–41) ** | IG: 2.5 (0–4.5) *** | RR: 100% | IG: 11 (1–27) ** | IG: 55.56 (46.87; 64.26) nmol/L **** | 96 | 1 | 20,000 IU + 500 mg calcium/day |
Placebo + 500 mg calcium/day |
IG: 100% | No adverse events | FSS |
| CG:41 (26–50) ** | CG: 26 (18–40) ** | CG: 2.0 (0–4.5) *** | CG: 10 (2–26) ** | CG: 57.33 (48.37; 66.28) nmol/L **** | CG: 91.67% | ||||||||||
| Rolf et al., (2017) [39] | Netherlands | 40 (26) | IG: 38.5 ± 7.8 | NR | IG: 2.0 (1.5–2.5) * | RR: 100% | IG: 7.5 (4.4–11.7) months * | IG: 58 (38–82) nmol/L * | 48 | 7 | 7000 IU first 4 weeks and 14,000 IU up to week 48 | Placebo | IG: 90.91% | NR | FSS |
| CG: 37.6 ± 9.6 | CG: 2.0 (1.5–2.3) * | CG: 5.7 (3.9–11.7) months * | CG: 53 (43–63) nmol/L * | CG: 92% | |||||||||||
| Rolf et al., (2018) [38] | Netherlands | 41 (41) | IG: 38.6 (28.0–45.0) * | NR | IG: 2.0 (1.4–2.0) * | RR: 100% | IG: 3.8 (2.8–11.4) * | IG: 85 (71–111) nmol/L * | 16 | 7 | 4000 IU | Placebo | IG: 92% | IG: headache and dizziness | FSS |
| CG: 35.1 (33.0–45.0) * | CG: 2.0 (1.0–2.5) * | CG: 5.4 (1.2–7.9) * | CG: 78 (68–95) nmol/L * | CG: 72.41% | CG: abdominal pain and stomach discomfort | ||||||||||
AT: home-based aerobic training, BMI: body mass index, CG: control group, EDSS: Expanded Disability Status Scale, FIS: Fatigue Impact Scale, IG: intervention group, IU: international units, mcg: micrograms, mg: milligrams, MFIS: Modified Fatigue Impact Scale, n: sample size, ng/mL: nanograms per milliliter, nmol/L: nanomoles per liter, NR: not reported, NA: not available, RCT: randomized clinical trial, RR: relapsing–remitting, SD: standard deviation, VitD: vitamin D, w: weeks, x: times per week, 25(OH)D: 25-hydroxy vitamin D, * = median (IQR); ** = mean (range); *** = median (range) **** = mean (95% CI).