Vitamin D deficiency and secondary hyperparathyroidism are common complications in patients with peripheral arterial disease

OBJECTIVE: To investigate via the vitamin D status whether patients with peripheral arterial disease (PAD) tend to develop vitamin D deficiency that in turn influences their clinical symptoms. DESIGN: Cross-sectional. SETTING: University hospital. PATIENTS AND PARTICIPANTS: Three hundred twenty-seven patients were evaluated; subjects with secondary causes of bone disease or bone active medication were excluded. One hundred sixty-one patients with either PAD stage 11 (n = 84) or stage IV (n = 77) were enrolled and compared to 45 age- and sex-matched healthy controls. MEASUREMENTS AND MAIN RESULTS: All patients underwent determinations of serum chemistry, 25-hydroxyvitamin D (vitamin D-3) intact parathyroid hormone (iPTH), alkaline phosphatase (ALP), and osteocalcin and were further stratified according to an individual restriction score into 3 groups: mildly, moderately, or severely restricted in daily life due to the underlying disease. Patients with PAD IV showed significantly lower vitamin D-3 (P = .0001), and calcium (P = .0001) values and significantly higher iPTH (P = .0001), osteocalcin (P = .0001) and ALP (P = .02) levels as compared to patients with PAD II. Patients considering themselves as severely restricted due to the underlying disease showed lower vitamin D-3 and higher iPTH levels than those who described only a moderate (vitamin D-3: P < .001; IPTH: P < .01) or mild (vitamin D-3: P < .001; iPTH: P < .001) restriction in daily life. CONCLUSION: Patients with PAD TV, especially those who feel severely restricted due to the disease, are at high risk of developing vitamin D deficiency, secondary hyperparathyroidism, and ultimately osteomalacia due to immobilization and subsequent lack of exposure to sunlight, all of which in turn lead to further deterioration. Monitoring of vitamin D metabolism and vitamin D replacement therapy could be a simple, inexpensive approach to mitigating clinical symptoms and improving quality of life in patients with advanced PAD.