Autoimmune Hepatitis May Increase Risk for Osteoporotic Fractures

Individuals with autoimmune hepatitis (AIH) have an increased risk for osteoporotic fractures, according to study results published in the American Journal of Gastroenterology.

Osteopenia is common among patients with chronic liver disease and may lead to osteoporosis and fragility fractures, likely due to altered bone metabolism and anabolic hormone deficiency. As a subset of liver disease, autoimmune hepatitis (AIH) may lead to osteoporosis via similar pathologic mechanisms. Due to the low incidence of osteoporotic fractures in those affected with AIH, researchers aimed to investigate the fracture risk associated with AIH.

A nationwide population-based cohort study was conducted using individuals from the Republic of Korea. Individuals with AIH, diagnosed using the Korea National Health Insurance Service (NHIS) from 2007 and 2020, were included in the study. An age- and sex-matched non-AIH control group were included at a ratio of 1:4. Those with chronic liver diseases, previous osteoporotic fractures, or a history of organ transplantation were excluded from the study.

The primary outcome was the development of any osteoporotic fracture, including vertebral, hip, distal radius, and proximal humerus. If an individual suffered multiple fractures during the study, each fracture was counted as a separate event.

A total of 7,062 individuals with AIH were included in the study, with an average follow-up of 5.4 years. Patients had a median age of 56 years, and the majority were women(84.3%).

During the study period, a total of 712 osteoporotic fractures occurred in patients with AIH, leading to an incidence rate (IR) of 17.45 (95% CI, 16.20-18.78) per 1,000 person years (PYs). Compared with the control group, those with AIH had a higher risk for osteoporotic fractures (incidence rate ratio [IRR], 1.51; 95% CI, 1.39-1.64).

Risk factors for osteoporotic fracture in those with AIH included female sex (adjusted hazard ratio [AHR], 2.17), older age (AHR, 5.05 and 12.10 in patients aged 41-64 years and ≥65 years, respectively), history of stroke (AHR, 1.68) and presence of liver cirrhosis (AHR, 1.55). Glucocorticoid use vs nonuse was associated with a 1.63-fold increase of fracture.

Patients with AIH were found to have a higher prevalence of comorbidities, including liver cirrhosis and a higher rate of prescription glucocorticoid use. Subgroup analysis adjusted for lifestyle and comorbidities found AIH patients to have a 1.24-fold higher risk for osteoporotic fracture when compared with matched control individuals. Notably, regular exercise (≥1 time/week) was associated with a lower risk for fracture (AHR, 0.87)

Study limitations include the inability to gather bone mineral density (BMD) test results at the onset of the study, as baseline results may have varied within the population.

“Female sex, older age, and presence of cirrhosis were also associated with an increased risk of the fracture,” study authors wrote. “Longer use of glucocorticoids further increased the risk of osteoporotic fracture. Considering the morbidities from osteoporotic fracture, recognition of these risk factors and early diagnosis and intervention may be crucial in the care of patients with AIH.”

This article originally appeared on Gastroenterology Advisor