Table 3.
Comparison of levels of biomarkers between cases and controls
| N measurements (n cases/ n controls) | Cases: Celiac disease antibody positive participantsa | Controls | OR (95% CI)b | |
|---|---|---|---|---|
| Number of participants | 169 | 676 | ||
| Median (5%/95%) | Median (5%/95%) | |||
| Cholesterol (mmol/L)* | 790 (cases:158/controls:632) | 5.5 (3.7/8.0) | 5.7 (4.1/7.8) | |
| 1st quartile | 1.56 (0.92–2.62) | |||
| 2nd quartile | 1.02 (0.60–1.74) | |||
| 3rd quartile | 0.84 (0.50–1.43) | |||
| 4th quartile | Ref | |||
| % (n/N) | % (n/ total N ) | |||
| Cholesterol under 5 mmol/L | 37.3 (59/158) | 28.3 (179/632) | 1.60 (1.08–2.37) | |
| Median (5%/95%) | Median (5%/95%) | |||
| Hemoglobin (mmol/L)* | 235 (cases:48/controls:187) | 8.4 (7.2/9.8) | 8.6 (7.6/9.9) | |
| 1st quartile | 1.44 (0.47–4.40) | |||
| 2nd quartile | 0.63 (0.21–1.83) | |||
| 3rd quartile | 0.63 (0.21–1.88) | |||
| 4th quartile | Ref | |||
| % (n/ total N ) | % (n/N) | |||
| Low hemoglobinc | 12.5 (6/48) | 4.3 (8/187) | 3.82 (1.14–12.79) | |
| Median (5%/95%) | Median (5%/95%) | |||
| Fasting blood glucose (mmol/L)* | 549 (cases:110/controls:439) | 4.8 (4.0/6.0) | 4.8 (3.9/6.3) | |
| 1st quartile | 0.84 (0.46–1.54) | |||
| 2nd quartile | 1.00 (0.56–1.79) | |||
| 3rd quartile | 0.68 (0.38–1.23) | |||
| 4th quartile | Ref | |||
| Fasting blood glucose over 7 mmol/L | 1.8 (2/110) | 2.5 (11/439) | 0.69 (0.14–3.48) | |
| Median (5%/95%) | Median (5%/95%) | |||
| HbA1c (%)* | 474 (cases:95/controls:379) | 5.8 (4.9/6.5) | 5.8 (5.0/6.5) | |
| 1st quartile | 1.26 (0.61–2.57) | |||
| 2nd quartile | 1.01 (0.53–1.92) | |||
| 3rd quartile | 1.14 (0.62–2.08) | |||
| 4th quartile | Ref | |||
| Median (5%/95%) | Median (5%/95%) | |||
| Ferritin (µg/L)* | 455 (cases:92/controls:363) | 74.5 (6.0/311.0) | 78.0 (8.0/298.0) | |
| 1st quartile | 1.41 (0.65–3.05) | |||
| 2nd quartile | 0.72 (0.36–1.43) | |||
| 3rd quartile | 0.69 (0.35–1.34) | |||
| 4th quartile | Ref | |||
| ALAT (Alanine transaminase)* (U/L) | 465 (cases:94/controls:371) | 10.8 (6.6/33.0) | 10.2(6.6/32.0) | |
| 1st quartile | 0.67 (0.17–2.73) | |||
| 2nd quartile | 0.63 (0.15–2.56) | |||
| 3rd quartile | 1.43 (0.41–4.07) | |||
| 4th quartile | Ref | |||
| ASAT (Aspartate aminotransferase) (U/L)* | 35 (cases:7/controls:28) | 20.0 (14.0/28.0) | 17.5 (13.0/38.0) | |
| 1st quartile | 0.63 (0.08–5.26) | |||
| 2nd quartile | 0.37 (0.04–4.01) | |||
| 3rd quartile | 0.34 (0.03–4.41) | |||
| 4th quartile | Ref | |||
| Alkaline phosphatase (ALP)* (U/L) | 385 (cases:77/controls:308) | 48.0 (28.2/90.0) | 44.4 (28.2/72.0) | |
| 1st quartile | 0.69 (0.34–1.40) | |||
| 2nd quartile | 0.63 (0.32–1.25) | |||
| 3rd quartile | 0.60 (0.30–1.20) | |||
| 4th quartile | Ref | |||
| % (n/ total N ) | % (n/ total N ) | |||
| Elevated liver parameters (ASAT/ALAT/ALP)d | 1.0 (1/102) | 2.2 (9/407) | 0.42 (0.05–3.48) | |
| Median (5%/95%) | Median (5%/95%) | |||
| Vitamin D (nmol/L)* | 474 (cases:95/controls:379) | 50.0 (10.0/107.0) | 54.0 (13.0/102.0) | |
| 1st quartile | 1.21 (0.63–2.30) | |||
| 2nd quartile | 1.41 (0.76–2.65) | |||
| 3rd quartile | 1.05 (0.55–2.01) | |||
| 4th quartile | Ref | |||
| Vitamin B12 (pmol/L)* | 385 (cases:77/controls:308) | 286.3 (159.4/513.6) | 295.9 (170.5/492.2) | |
| 1st quartile | 1.22 (0.63–2.38) | |||
| 2nd quartile | 0.81 (0.39–1.69) | |||
| 3rd quartile | 0.64 (0.30–1.36) | |||
| 4th quartile | Ref |
*The quartiles were calculated per each of the eight studies
Statistically significant values are shown in bold
aThe participants were screened for celiac disease antibodies by EliA™ Celikey® tissue transglutaminase (TTG) anti-IgA and anti-IgG assays and deamidated gliadin peptide (DGP) anti-IgG assays. Celiac disease antibody positive were defined as IgG-DGP ≥ 10.0 U/mL and/or IgA-TTG/IgG-TTG ≥ 7.0 U/mL. 5 of the 16,776 participants had a diagnosis of celiac disease in the national patient register, they were all celiac disease antibody negative and were excluded before matching. Cases were matched without replacement on age (5 years range), sex and study to 4 controls
bConditional logistic regression for comparison of cases with controls giving odds ratios (ORs) with 95% confidence intervals (CIs)
cLow hemoglobin was defined as hemoglobin under 7.3 mmol/L for women and under 8.3 mmol/L for men
dElevated liver parameters was defined as ALAT over 70 U/L for men and over 45 U/L for women, ASAT over 45 U/L for men and over 35 U/L for women, and alkaline phosphatase (ALP) over 105 U/L, 376 participants both had measurements for ALAT and ALP