Vitamin-D Receptor-Gene Polymorphisms Affect Quality of Life in Patients with Autoimmune Liver Diseases

Abstract

Vitamin D deficiency has been associated with depressive symptoms and reduced physical functioning. The aim of the study was to characterize the relationship between polymorphisms of the vitamin D receptor (VDR) gene and the quality of life in patients with autoimmune hepatitis (AIH) and primary biliary cholangitis (PBC). Three polymorphisms of the <i>VDR</i> gene (<i>TaqI-rs731236</i>, <i>BsmI-rs1544410</i>, and <i>ApaI-rs7975232</i>) were analyzed in patients with AIH (<i>n</i> = 142) and PBC (<i>n</i> = 230) and in healthy individuals (<i>n</i> = 376). Patient quality of life was assessed by validated questionnaires such as Medical Outcomes Study Short-Form 36 (SF-36), State Trait Anxiety Inventory (STAI), Modified Fatigue-Impact Scale (MFIS), Patient-Health Questionnaire 9 (PHQ-9), and PBC-40. The <i>TaqI</i> C and <i>ApaI</i> A alleles are risk alleles in both AIH and PBC, and a significant dominance of the A allele in <i>BsmI</i> was observed in AIH patients. In terms of quality of life, the presence of the CC or CT <i>TaqI</i> genotype was associated with emotional reactions, including the fatigue and the cognitive skills of patients with PBC, whereas in the group of AIH patients, homozygotes CC of <i>TaqI</i>, AA of <i>BsmI</i>, and AA of <i>ApaI</i> had worse physical, social, emotional, and mental function. The genetic variations of <i>VDR</i> gene can influence individual susceptibility to develop chronic autoimmune liver diseases such as AIH and PBC and affect quality of life.