The Relationship of α-Klotho Level with Vitamin D, Calcium, Phosphorus and Parathyroid Hormone in the Ankylosing Spondylitis

This study aimed to evaluate the relationship between -klotho levels and 25(OH)-vitamin D, calcium, phosphorus, and parathyroid hormone (PTH) in ankylosing spondylitis (AS) patients. Eighty-five patients aged 18-65, admitted to outpatient clinics between August 1 and September 1, 2019, were included. Patients with AS for at least 5 years (32, 37.6%) were assigned to the AS group, while those without known diseases (53, 62.4%) were placed in the healthy group. The -klotho level was 0.60 [0.33] ng/mL in the AS group and 0.68 [1.59] ng/mL in the healthy group (p=0.209). In the AS group, those with vitamin D deficiency had a klotho level of 0.599 [1.751] ng/mL, compared to 0.605 [0.499] ng/mL in those without (p=0.952). In the healthy group, levels were 1.309 [10.110] ng/mL and 0.641 [0.879] ng/mL, respectively (p=0.195). No significant relationships were found between -klotho levels and vitamin D, PTH, calcium, phosphorus, or ALP in either group. Although some studies suggest a link between vitamin D and -klotho, further research is needed.