Table 1.
Summary characteristics of included studies.
| First author country |
Total N | Age Years | % Male | Low Vitamin D* cutoff | Study design | Comorbidity % >10% | Ref. |
|---|---|---|---|---|---|---|---|
| Abrishami Iran |
73 | 55 | 64% | <25 ng/ml | Retrospective study | Hypertension (24.7%) Chronic kidney disease (21.9%) |
(25) |
| Adami Italy |
61 | 69.4 | 52.5% | <20 ng/ml | Retrospective observational study | Hypertension (59%) Cardiovascular diseases (27.8%) Diabetes. (18%) Cancer (18%) Chronic kidney disease (18%) Chronic obstructive pulmonary disease (18%) |
(26) |
| Angelidi USA |
144 | 66 | 44.4% | <30 ng/ml | Retrospective, observational, cohort | Hypertension (73.6%) Hyperlipidemia (54.9%) Diabetes. (43.8%) |
(27) |
| Anjum Pakistan |
140 | 42.5 | 58.6% | <10 ng/ml | Prospective cohort | NR | (28) |
| Baktash UK |
70 | 80 | 70% | <30 ng/ml | Prospective cohort study | Hypertension (48.5%) Diabetes (37.1%) |
(29) |
| Carpagnano Italy |
42 | 65 | 71% | <30 ng/ml | Retrospective, observational single center study | Total: 86% Hypertension (26%) |
(30) |
| Cereda Italy |
129 | 77 | 54% | <20 ng/ml | Prospective cohort | Hypertension (70.1%) Ischemic heart disease (40.9%) Diabetes. (30.7%) |
(31) |
| Charoenngam USA |
287 | 62 | 52.6% | <30 ng/ml | Retrospective chart review cross-sectional study | Hypertension (79.9%) Diabetes (56%) Hyperlipidemia (58.2%) Chronic kidney disease (37.6%) |
(32) |
| Demir Turkey |
227 | 46.3 | 44.66% | <30 ng/ml | Retrospective cohort study | NR | (33) |
| De Smet Belgium |
186 | 69 | 58.6% | <20 ng/ml | Retrospective observational trial | Coronary artery disease (61.5%) |
(34) |
| Gavioli USA |
437 | 67 | 48% | <30 ng/ml | Retrospective, observational cohort study | Hypertension (68%) Diabetes (45%) Coronary artery disease (30%) Malignancy (24%) |
(35) |
| Hernandez Spain |
197 | 61 | 62.4% | <20 ng/ml | Retrospective case-control study | Hypertension (38.6%) | (36) |
| Jevalikar India |
409 | 54 | 68.9% | <20 ng/ml | Prospective observational study | Diabetes (46.1%) Hypertension (40%) Hypothyroidism (14.9%) |
(37) |
| Karahan Turkey |
149 | 63.5 | 54.4% | <20 ng/ml | Retrospective observational study | Hypertension (57%) Diabetes (40.9%) Dyslipidemia (26.2%) Coronary artery disease (21.5%) Chronic kidney disease (19.5%) |
(38) |
| Luo China |
74 | 62.5 | 58.1% | <30 ng/ml | Retrospective cross-sectional study | Total 67.6% | (39) |
| Maghbooli Iran |
235 | 59 | 61.3% | <30 ng/ml | Retrospective cross-sectional study/analysis |
Hypertension (44.4%) Diabetes (36.6%) |
(40) |
| Orchard UK |
50 | 60 | 56% | <20.83 ng/ml | Prospective cohort | Hypertension (40%) Diabetes (28%) Asthma (10%) |
(41) |
| Radujkovic Germany |
185 | 60 | 51% | <12 ng/ml | Prospective cohort | Cardiovascular disease (31%) | (42) |
| Ricci Italy |
52 | 68.4 | 48 % | <10 ng/ml | Cohort | Hypertension (42.3%) Obesity (23%) |
(43) |
| Tehrani Iran |
205 | 59.7 | 69% | <30 ng/ml | Descriptive retrospective study | Hypertension (44.4%) Diabetes (35.1%) Ischemic heart disease (24.9%) Chronic kidney disease (23.4%) |
(44) |
| Vassiliou Greece |
30 | 65 | 80% | <15.2 ng/ml | Retrospective observational study | Hypertension (50%) Hyperlipidemia (30%) |
(45) |
| Ye China |
60 | 43 | 37% | <12 ng/ml | Case control study | Hypertension (10%) Renal failure (26.6%) Diabetes (8.3%) |
(46) |
| Kerget Turkey |
88 | 49.1 | 46.6% | <20 ng/ml | Prospective cohort | Hypertension (11.36%) Diabetes (9%) |
(47) |
| Jain India |
154 | 46 | 48.5% | < 20 ng/ml | Prospective observational study | Diabetes Hypertension |
(48) |
*
Low vitamin D = vitamin D levels ranges from <10 to <30 ng/ml, NR: not reported.