Table 2.
Comparing Patients with and Without Functional Gastrointestinal Symptoms Against Controls Concerning the Degree of Hypothalamus-Pituitary-Adrenal Axis Suppression Post-dexamethasone Suppression Test
| HPA-axis suppression post-DST | P-valuesa (vs controls) | |||
|---|---|---|---|---|
|
|
||||
| Hypersuppressors (cortisol < 130 nmol L−1) | Intermediate (cortisol 130–500 nmol L−1) | Hyposuppressors (cortisol > 500 nmol L−1) | ||
| Controls (n = 146, n [%]) | 14 (10) | 118 (80) | 14 (10) | |
| Patients with functional GI symptoms (n = 30, n [%])b | 8 (27) | 18 (60) | 4 (13) | 0.023 |
| Patients without functional GI symptoms (n = 31, n [%])b | 4 (13) | 22 (71) | 5 (16) | 0.370 |
The 2 analyses are comparisons concerning the categorized post-dexamethasone suppression test (DST) cortisol distribution between the patients with functional gastrointestinal (GI) symptoms and the controls as well as between the patients without functional GI symptoms and controls.
Patients with and without functional GI symptoms were defined as those patients with a gastrointestinal symptom rating scale-irritable bowel syndrome (GSRS-IBS) score above or below the median score for the whole patient sample.
HPA, hypothalamus-pituitary-adrenal; IBS, irritable bowel syndrome.
Significance testing performed with Fisher’s exact test. The lowest 10 % (n = 14) and the highest 10 % cutoffs (n = 14) of the post-DST cortisol values (< 130 nmol L−1 and > 500 nmol L−1 respectively) among the controls were defined as hyper- and hyposuppression respectively and the remaining 80 % (n = 118) were defined as intermediate HPA-axis suppression.