Table 4.
Results of RCTs.
| Author, Year | Outcomes Evaluated | Mean (SD) Baseline 25OHD (nmol/L) | Mean (SD) Endline 25OHD (nmol/L) | Mean (SD) Baseline BP (mmHg) | Mean (SD) Endline BP (mmHg) | Conclusion |
|---|---|---|---|---|---|---|
| Al Daghri, 2019 [28] | 25OHD: enzyme linked immunosorbent assay | Tablet: 30.8 (9.3) Milk: 31.8 (8.1) C: 29.8 (10.3) (p = 0.46) |
Tablet: 41.5 (14.4) Milk: 38.1 (11.9) C: 31.9 (13.8) (p < 0.001) (p = 0.73 between tablet and milk; <0.001 between tablet and C; p < 0.001 between milk and control) |
SBP: Tablet: 117.3 (14.4) Milk: 117.9 (14.4) C: 120.9 (14.9) (p = 0.75) |
SBP: Tablet: 112.3 (12.3) Milk: 115.3 (16.1) C: 117.1 (14.9) (p = 0.005) (p = 0.44 between tablet and milk; p = 0.004 between tablet and C; p = 0.19 between milk and C) |
Significant decrease in SBP in all groups. Between-group significant decrease in favor of the tablet group (p = 0.005) |
| SBP and DBP: average of 2 measures by a conventional mercurial sphygmomanometer taken after a 30-minute rest | DBP: Tablet: 71.9 (11.9) Milk: 73.3 (15.7) C: 72.5 (11.6) (p = 0.50) |
DBP: Tablet: 69 (11.4) Milk: 75.6 (15.7) C: 68.1 (11.1) (p < 0.001) (p < 0.001 between tablet and milk; p = 0.94 between tablet and C; p < 0.001 between milk and C) |
Significant decrease in DBP in the tablet and control groups. Between-group significant improvement in favor of control (p < 0.001) | |||
| Elevated BP: ≥90th percentile for age, sex and height | Elevated BP: Tablet: 38.9% Milk: 40.7% C: 34.9% |
Elevated BP: Tablet: 25.0% (p < 0.001) Milk: 44.4% (NS) C: 24.7% (p < 0.05) |
Significant reduction in elevated BP in the tablet and control groups (p < 0.05) | |||
| Dong, 2010 [29] | Plasma 25OHD: enzyme immunoassay | I: 33.1 (8.7) C: 34.0 (10.6) (p = 0.76) |
I: 85.7 (30.1) C: 59.8 (18.2) (p < 0.001) |
SBPI: 111.3 (10.4) C: 114.9 (7.8) (p = 0.20) |
NR | NS change in SBP or DBP over time in the control or intervention groups (p > 0.05) |
| SBP and DBP: average of 3 measures, 2 minutes apart, by a vital signs monitor after a 5-minute rest | DBP I:68.2 (12.3) C: 69.4 (6.5) (p = 0.17) |
|||||
| Hauger, 2018 [32] | Serum 25OHD: liquid chromatography-tandem mass spectrometry |
I1: 56.9 (12.7) I2: 58.1 (13.5) C: 55.2 (10.8) |
I1: 61.8 (10.6) I2: 75.8 (11.5) C: 31.1 (7.5) (p < 0.001) |
SBP: I1: 95.7 (4.6) I2: 96.4 (4.4) C: 97.1 (5.5) |
SBP: I1: 95.6 (4.4) I2: 96.9 (4.4) C: 96.6 (4.2) (NS) |
NS change in SBP or DBP when adjusted for baseline value of the outcome |
| Marginally higher DBP of 1.4 mmHg (95% CI: −0.0,2.8; p = 0.05) in I1 compared with I2 | ||||||
| SBP and DBP: average of 2 out of 3 readings, 10 minutes apart, by an automated monitor in a supine position | DBP: I1: 58.8 (4.1) I2: 59.9 (4.6) C: 59.2 (4.1) |
DBP: I1: 58.5 (4.5) I2: 60.5 (3.8) C: 59.9 (3.3) (NS) |
Marginally lower DBP of −1.2mmHg (95% CI: −2.7, −0.0; p = 0.05) in I1 compared with C, which was not observed with I2 | |||
| Kelishadi, 2014 [30] | Serum 25OHD: chemiluminescent immunoassay method | I: 45.60 (5.09) C: 44.7 (5.66) (p = 0.48) |
I: 79.89 (5.34) C: 47.59 (5.01) (p = 0.02) |
I: 134.01 (5.89) C: 136.61 (6.08) (p = 0.53) |
I: 131.47 (4.69) C: 135.26 (4.52) (p = 0.07) |
NS change in mean arterial pressure in intra-group and inter-group comparisons |
| Mean arterial pressure: ((SBP − DBP)/3) + DBP; with SBP and DBP measured using standard protocol with calibrated instruments (procedure not detailed) | ||||||
| Smith, 2018 [31] | Serum 25OHD: liquid chromatography-tandem mass spectrometry | I1: 49.2 (12) I2: 51.7 (13.4) C: 46.9 (11.4) |
I1: 56.6 (12.4) I2: 63.9 (10.6) C: 30.7 (8.6) (p < 0.001 for all groups, from baseline to endline) |
SBP: I1: 124 (13) I2:122 (10) C: 121 (10) |
SBP: I1: 123 (11) I2: 121 (8) C: 123 (14) (NS) |
NS change in SBP or DBP |
| SBP and DBP: average of 3 readings, 1 min apart, by an automated BP monitor on the non-dominant arm in an upright position with the arm supported | DBP: I1: 69 (10) I2: 67 (7) C: 67 (8) |
DBP: I1: 71 (11) I2: 67 (6) C: 68 (10) (NS) |
SD: standard deviation; 25OHD: 25-hydroxyvitamin D; BP: blood pressure; SBP: systolic blood pressure; DBP: diastolic blood pressure; C: control; I: intervention; NR: not reported; NS: not significant.