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

Abstract

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 II (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 D3) 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 D3 (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 D3 and higher iPTH levels than those who described only a moderate (vitamin D3: P <.001; iPTH: P <.01) or mild (vitamin D3: P <.001; iPTH: P <.001) restriction in daily life.

Conclusion: Patients with PAD IV, 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.

FIGURE 1

Comparisons of the mean vitamin D₃ (25-hydroxyvitamin D) and intact parathyroid hormone (iPTH) levels between Group A, Group B, and the Control Group. Patients with peripheral arterial disease (PAD) IV had highly significant lower vitamin D₃ and significantly higher iPTH levels as compared to the Control Group and to patients with PAD II.

FIGURE 2

Vitamin D₃ (25-hydroxyvitamin D) serum levels in relation to the patient's individual restriction score.Patients with a subjective feeling of being severely immobilized and restricted in personal life had significantly lower vitamin D₃ levels as compared to those who described themselves as only moderately or mildly handicapped. Throughout the 3 groups, it was evident that patients with PAD IV (black columns) had significantly lower vitamin D₃ levels compared to PAD II patients (gray columns).