Table 1.
Baseline characteristics and laboratory results of IBD patients
| Total | CD patients | UC patients | p valuea | |
|---|---|---|---|---|
| n = 316 | n = 131 | n = 185 | ||
| Age, years (SD) | 48.5 (14.8) | 46.5 (14.7) | 49.9 (14.8) | 0.046 |
| Women, n (%) | 181 (57.3) | 84 (64.1) | 97 (52.4) | 0.039 |
| Postmenopausal state, n (% of women) | 71 (39.2) | 32 (38.1) | 39 (40.2) | NS |
| Body mass index, kg/m2 (SD) | 25.3 (4.5) | 25.5 (4.8) | 25.1 (4.3) | NS |
| Active IBD, n (%) | 160 (50.6) | 70 (53.4) | 90 (48.6) | NS |
| Disease duration IBD, years (SD) | 11.0 (9.7) | 11.1 (10.0) | 11.0 (9.6) | NS |
| Exacerbation IBD, episodes/year (SD) | 2.7 (2.1) | 2.8 (2.2) | 2.7 (1.9) | NS |
| History of >7.5 mg daily corticosteroid usage for at least 6 months, n (%) | 92 (29.1) | 38 (29.0) | 54 (29.2) | NS |
| Daily use of oral vitamin D supplementation, n (%) | 106 (33.5) | 42 (32.1) | 64 (34.6) | NS |
| Low dietary calcium intake, n (%) | 15 (4.8) | 6 (4.6) | 9 (4.9) | NS |
| Fatty fish intake, units/month (SD) | 2.6 (2.5) | 2.6 (2.3) | 2.7 (2.5) | NS |
| Excessive alcohol usage, n (%) | 34 (10.9) | 11 (8.5) | 23 (12.6) | NS |
| Current smoking, n (%) | 73 (23.1) | 46 (35.1) | 27 (14.6) | <0.001 |
| Preferred exposure to sun when outdoors, n (%) | 166 (53.7) | 61 (36.7) | 105 (63.3) | 0.041 |
| Outdoor activities at least 2 h a day | ||||
| Summer, days/week (SD) | 4.5 (2.1) | 5.4 (2.1) | 5.4 (2.1) | NS |
| Winter, days/week (SD) | 3.0 (2.5) | 3.1 (2.5) | 2.9 (2.4) | NS |
| Sun holiday in the last year, n (%) | 138 (44.5) | 49 (37.7) | 89 (49.4) | 0.040 |
| Solarium visits, n (%) | 64 (20.6) | 27 (20.8) | 37 (20.6) | NS |
| Laboratory markers in serum | ||||
| Hb, mmol/L (SD) | 8.6 (0.92) | 8.5 (0.90) | 8.7 (0.93) | NS |
| Ht, L/L (SD) | 0.41 (0.04) | 0.40 (0.04) | 0.41 (0.04) | NS |
| RDW, % (SD) | 44.6 (4.8) | 45.8 (5.2) | 43.7 (4.2) | <0.001 |
| ESR, mm/h (SD) | 14.1 (12.7) | 15.7 (10.8) | 13.0 (13.8) | <0.001 |
| CRP, mg/L (SD) | 4.5 (7.7) | 5.1 (6.4) | 4.1 (8.6) | <0.001 |
| Calcium, mmol/L (SD) | 2.3 (0.1) | 2.4 (0.1) | 2.3 (0.09) | NS |
| Phosphate, mmol/L (SD) | 1.1 (0.2) | 1.1 (0.2) | 1.1 (0.2) | NS |
| Albumin, g/L (SD) | 40.6 (3.2) | 40.1 (3.2) | 40.9 (3.2) | 0.006 |
| Creatinine, μmol/L (SD) | 72.9 (15.7) | 71.2 (13.7) | 74.2 (16.8) | NS |
| TSH, mIU/L (SD) | 1.53 (0.87) | 1.50 (0.95) | 1.54 (0.81) | NS |
SD standard deviation, Hb haemoglobin, Ht haematocrit, RDW red blood cell distribution width, ESR erythrocyte sedimentation rate, CRP C-reactive protein, TSH thyroid stimulating hormone
aStatistical analyses between CD and UC patients were performed by using a parametric test (unpaired t test) when a normal distribution was present and when in order a non-parametric test (Mann–Whitney U) to assess univariate significant associations between the stated continuous determinants and CD vs. UC. Categorical determinants were analysed by using Pearson’s Chi-square test (or Fisher’s exact test when expected frequencies were low). All p values >0.10 are noted as NS (non-significant). All p values between 0.5 and 0.10 are noted in order to evaluate non-significant trends associated between the groups