Table 1.
Patients’ characteristics at the two centers
| Oslo University Hospital Aker | Innlandet Hospital Trust Gjøvik | ||||
|---|---|---|---|---|---|
| n | n | p-value | |||
| Gender (%male) | 62 (29%) | 211 | 28 (20%) | 139 | 0.05# |
| Age (years) | 43 (21–61) | 211 | 44 (24–61) | 139 | 0.66* |
| Body mass index (kg/m2) | 43 (33–62) | 211 | 42 (35–53) | 139 | 0.09* |
| Ethnicity (% Caucasian) | 195 (93%) | 210 | 139 (100%) | 139 | 0.001# |
| Irritable bowel syndrome (IBS) | 17/211 (8%) | 211 | 37/139 (26%) | 139 | <0.001# |
| IBS-constipation | 3/17 (18%) | 17 | 7/37 (19%) | 37 | 0.48# |
| IBS-diarrhea | 2/17 (12%) | 17 | 11/37 (30%) | 37 | |
| IBS-mixed | 11/17 (65%) | 17 | 18/37 (49%) | 37 | |
| IBS-unsubtyped | 1/17 (6%) | 17 | 1/37 (3%) | 37 | |
| Functional bloating | 21/205 (10%) | 205 | 19/138 (14%) | 138 | 0.32# |
| Functional constipation | 20/205 (10%) | 205 | 3/135 (2%) | 138 | 0.006# |
| Functional diarrhea | 9/206 (4%) | 206 | 4/139 (3%) | 139 | 0.48# |
| Smoking | 56/204 (28%) | 204 | 24/139 (17%) | 139 | 0.03# |
| Diabetes mellitus | 53/211 (25%) | 211 | 26/139 (19%) | 139 | 0.16# |
| Hypothyroidism | 19/211 (9%) | 211 | 17/138 (12%) | 138 | 0.32# |
| Fibromyalgia | 20/211 (10%) | 211 | 25/138 (18%) | 138 | 0.02# |
| Self-reported psychiatric disorder | 36/211 (17%) | 211 | 29/139 (21%) | 139 | 0.37# |
| Hemoglobin (g/dl) | 14.1 (1.1) | 211 | 14.5 (1.1) | 136 | 0.006 |
| White-cell count (×109/l) | 7.4 (2.4–13.3) | 210 | 7.5 (4.2–16.1) | 136 | 0.95* |
| Platelet count (×109/l) | 275 (112–519) | 210 | 276 (131–939) | 134 | 0.46* |
| HbA1C (%) | 5.8 (4.7–14.9) | 211 | 5.5 (4.5–11.5) | 136 | <0.001* |
| Bilirubin (μmol/l) | 7 (2–23) | 210 | 6 (2–28) | 136 | 0.07* |
| C-reactive protein (mg/l) | 7 (1–50) | 210 | 5 (0–43) | 136 | 0.01* |
| Cholesterol (mmol/l) | 4.9 (1.0) | 210 | 5.1 (1.0) | 136 | 0.10 |
| High-density lipoprotein (mmol/l) | 1.1 (0.5–2.0) | 210 | 1.1 (0.4–2.2) | 136 | 0.70* |
| Low-density lipoprotein (mmol/l) | 3.1 (0.9) | 210 | 3.3 (0.9) | 136 | 0.02 |
| Thyroid stimulating hormone (mIE/l) | 1.4 (0–14.6) | 210 | 1.7 (0–6.9) | 136 | 0.11* |
| Free T4 (pmol/l) | 15 (11–28) | 210 | 15 (10–26) | 136 | 0.30* |
| Vitamin B1 (nmol/l) | 156 (62–239) | 210 | 153 (104–246) | 135 | 0.70* |
| Vitamin B6 (nmol/l) | 29 (5–231) | 211 | 22 (5–209) | 133 | 0.01* |
| Vitamin B12 (pmol/l) | 344 (158–1480) | 211 | 346 (158–1401) | 136 | 0.80* |
| Folic acid (nmol/l) | 18 (6–46) | 211 | 17 (7–46) | 136 | 0.14* |
| Use of statins | 35/211 (17%) | 211 | 19/138 (14%) | 138 | 0.48# |
| Use of thyroid substitution therapy | 19/211 (9%) | 211 | 13/139 (9%) | 139 | 0.91# |
The results are given as number (proportion in percent) for categorical variables, mean (standard deviation) for continuous variables with normal distribution and median (range) for other continuous variables. Data were analyzed with with t-tests, Pearson chi-squared tests (marked with #) or Mann-Whitney U test (marked with *)