Genetic, Immunological, Dietary, Gut Microbiota, and Environmental Determinants of Osteoporosis in the Course of Celiac Disease: Which Factor Plays the First Violin in This Orchestra?

Celiac disease (CD) is a chronic small intestinal immune-mediated enteropathy precipitated by exposure to dietary gluten in genetically predisposed individuals. The worldwide prevalence of CD is estimated to be 0.7-1.4% of the general population. Etiopathology of this disease is multifactorial, with genetic determinants being a major contributing player to CD susceptibility. Its manifestation embraces different organs, including the musculoskeletal apparat. Patients with CD have increased risk of bone disorders. According to data, bone disorders - osteopenia and osteoporosis - can affect up to 70% of patients with CD at diagnosis, and it decreases after the initiation of a gluten-free diet. Gluten consumption in patients with CD triggers an inflammatory reaction followed by tissue damage, and both; local and systemic inflammation can increase the risk of bone mass deterioration. Other theory assumes shortages of vitamin D and an impaired calcium absorption mechanism leading to secondary hyperparathyroidism. Taking into account the increasing prevalence of CD and osteoporosis, we broadly discuss genetic, immunological, dietary, gut microbiota, and environmental factors that could increase the risk of osteoporosis in CD. Furthermore, we discuss lifestyle and pharmacological preventing and treatment measures.