title: Serum vitamin D deficiency and its association with systemic disease in exfoliation syndrome.
abstract: OBJECTIVE
  To determine the association of serum vitamin D levels with exfoliation syndrome (XFS) and evaluate its impact on co-associated systemic diseases.
  
  
  METHODS
  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.
  
  
  RESULTS
  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.
  
  
  CONCLUSIONS
  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.
authors.affiliation: Department of Ophthalmology, Hacettepe University School of Medicine, Ankara, Turkey.
authors.forename: Sibel
authors.initials: S
authors.lastname: Kocabeyoglu
authors.forename: Mehmet Cem
authors.initials: MC
authors.lastname: Mocan
authors.forename: Murat
authors.initials: M
authors.lastname: Irkec
authors.forename: Asli
authors.initials: A
authors.lastname: Pinar
authors.forename: Banu
authors.initials: B
authors.lastname: Bozkurt
authors.forename: Mehmet
authors.initials: M
authors.lastname: Orhan
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001327:Autoimmune Diseases / Q000453:epidemiology / Q000209:etiology; D002318:Cardiovascular Diseases / Q000453:epidemiology / Q000209:etiology; D016022:Case-Control Studies; D002561:Cerebrovascular Disorders / Q000453:epidemiology / Q000209:etiology; D003920:Diabetes Mellitus / Q000453:epidemiology / Q000209:etiology; D017889:Exfoliation Syndrome / Q000097:blood* / Q000150:complications; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009422:Nervous System Diseases / Q000453:epidemiology / Q000209:etiology; D015995:Prevalence; D011446:Prospective Studies; D014807:Vitamin D / Q000031:analogs & derivatives* / Q000097:blood; D014808:Vitamin D Deficiency / Q000150:complications*
chemical_list: D014807:Vitamin D; C104450:25-hydroxyvitamin D