Serum vitamin D deficiency and its association with systemic disease in exfoliation syndrome

To determine the association of serum vitamin D levels with exfoliation syndrome (XFS) and evaluate its impact on co-associated systemic diseases.

Forty patients with XFS and 40 control subjects without XFS were recruited for this study. Se-rum concentrations of 25-hydroxy vitamin D [25(OH) D] were measured by high-performance liquid chromatography. Vitamin D deficiency was defined as a serum 25(OH) D concentration of <20 ng/mL. A detailed medical history including hypertension, diabetes mellitus, ischemic heart disease, cerebrovascular stroke, autoimmune disease, and neurologic disorders such as Parkinson disease and Alzheimer disease was recorded. Student t test and chi-square test was used for statistical evaluations.

The mean age of patients with XFS and control subjects was 69.6 ± 8.1 years (range 58-90 years) and 67.1 ± 6.3 years (range 60-86 years), respectively (p>0.05). Mean 25(OH) D levels did not differ between XFS (19.8 ± 8.3 ng/mL) and control (19.9 ± 10.3 ng/mL) groups (p = 0.978). Patients with XFS had higher prevalence of cerebrovascular (p = 0.026) and cardiovascular disease (p = 0.001). There was no association between the systemic disease status and serum vitamin D levels of patients with XFS.

Although vitamin D levels were similar between XFS and control subjects, the levels were found to be decreased in both groups. Patients with XFS had a significantly higher prevalence of cerebrovascular and cardiovascular disease as compared to controls independent of their serum 25(OH) D levels. Low vitamin D level does not appear to be linked to XFS in the studied population.