Delayed bile flow may induce the formation/accumulation of common bile duct stones (CBDS). Bile flow is delayed in hypothyroidism, partly due to insufficient sphincter of Oddi relaxation. Patients with CBDS have higher incidences of clinical and subclinical hypothyroidism compared to healthy controls and gallbladder stone patients. The aim of this large registry-based study was to investigate the prevalence of CBDS in patients with diagnosed hypothyroidism compared to age-, sex- and living area-adjusted glaucoma (control) patients.
Between 1987 and 2001, all patients with approved Special Medical Coverage (SMC) for hypothyroidism or glaucoma, and without other SMC approvals, were included. The glaucoma (control) cohort was adjusted for age, sex and area of residence. For each patient, onset of SMC, all prescription drugs and treatments for CBDS were noted.
A total of 14,334 patients in each group met the inclusion criteria. Thirty-three patients (0.23%) in the hypothyroidism cohort and 23 (0.16%) in the glaucoma cohort had been treated for CBDS (p = 0.018). The groups did not differ in the number of CBDS treatments before the diagnosis of hypothyroidism or glaucoma. However, after the diagnosis of hypothyroidism or glaucoma there were significantly more CBD stone patients in the hypothyroid cohort (n = 25) than in the glaucoma cohort (n = 14) (p