Gallstone Disease and Its Association with Hypothyroidism: A Case-Control Study from a Tertiary Care Centre in...

Biliary stasis is a principal driver of gallstone formation. Hypothyroidism promotes lithogenesis through altered lipid metabolism, sphincter of Oddi dysfunction, and impaired gallbladder contractility, thereby promoting bile cholesterol supersaturation. The objectives of this study were (1) to determine whether a statistically significant association exists between gallstone disease and hypothyroidism and (2) to identify whether gallstone composition correlates with thyroid status.

A prospective case-control study was conducted in the Department of General Surgery at a tertiary care hospital in Puducherry, India, over 25 months (November 2019-November 2021). Patients with ultrasound-confirmed gallstone disease (cases, n = 47) were compared with gallstone-free patients (controls, n = 84). Serum thyroid-stimulating hormone (TSH) was measured by a third-generation chemiluminescence immunometric assay. Gallstone composition was assessed post-operatively by qualitative biochemical analysis (Liebermann-Burchard reaction). Statistical analysis used IBM SPSS Statistics software version 20 (IBM Corp., Armonk, NY, USA); p < 0.05 was considered significant.

Of 47 cases, 19.1% were hypothyroid versus 0% of controls (χ² = 14.41, p = 0.00015). The Haldane-Anscombe-corrected odds ratio (OR) was 14.88, indicating approximately 15-fold greater odds of gallstone disease in hypothyroid individuals. Mixed-type stones predominated (93.6%), followed by cholesterol-type (4.3%) and pigment-type (2.1%). All nine hypothyroid cases had mixed-type stones. Cases clustered in the 30-39-year age group (48.9%).

Hypothyroidism is significantly associated with gallstone disease. The predominance of mixed stones is mechanistically consistent with bile cholesterol supersaturation driven by thyroid hormone deficiency. TSH screening can be considered to be incorporated into the diagnostic workup for cholelithiasis, particularly in high-prevalence populations.