title: Serum Vitamin D Status in Iranian Fibromyalgia Patients: according to the Symptom Severity and Illness Invalidation.
abstract: BACKGROUND
  This study was designed to assess serum vitamin D status (25-OHD) in the fibromyalgia (FM) patients and to compare it with a healthy control group. It also aimed to investigate the correlation of serum vitamin D level with FM symptom severity and invalidation experiences.
  
  
  METHODS
  A total of 74 consecutive patients with FM and 68 healthy control participants were enrolled. The eligible FM patients completed the Illness Invalidation Inventory (3(*)I), the Revised Fibromyalgia Impact Questionnaire (FIQR) and a short-form health survey (SF-12). Venous blood samples were drawn from all participants to evaluate serum 25-OHD levels. Mann-Whitney tests and multiple logistic regression analyses were performed and Spearman's correlations were calculated.
  
  
  RESULTS
  88.4% of FM patients had low levels of serum 25-OHD. FM patients had significantly higher level of serum 25-OHD than the control group (17.24 ± 13.50 and 9.91 ± 6.47 respectively, P = 0.0001). There were no significant correlations between serum 25-OHD levels and the clinical measures of disease impact, invalidation dimensions, and health status. Multiple logistic regression analyses revealed that an increased discounting of the disease by the patient's spouse was associated with a 4-fold increased risk for vitamin D deficiency (OR = 4.36; 95% CI, 0.95-19.87, P = 0.05).
  
  
  CONCLUSIONS
  This study showed that although high rates of vitamin D insufficiency or deficiency were seen among FM patients and healthy non-FM participants, but it seems there was no intrinsic association between FM and vitamin D deficiency. Addressing of invalidation experience especially by the patient's spouse is important in management of FM.
authors.affiliation: Student Research Center, Razi Hospital, School of Medicine, Guilan University of Medical Sciences, Rasht, Iran.
authors.forename: Alireza Amir
authors.initials: AA
authors.lastname: Maafi
authors.affiliation: Rheumatology Research Center, Razi Hospital, School of Medicine, Guilan University of Medical Sciences, Rasht, Iran.
authors.forename: Banafsheh
authors.initials: B
authors.lastname: Ghavidel-Parsa
authors.affiliation: Student Research Center, Razi Hospital, School of Medicine, Guilan University of Medical Sciences, Rasht, Iran.
authors.forename: Afrooz
authors.initials: A
authors.lastname: Haghdoost
authors.affiliation: Student Research Center, Razi Hospital, School of Medicine, Guilan University of Medical Sciences, Rasht, Iran.
authors.forename: Yasaman
authors.initials: Y
authors.lastname: Aarabi
authors.affiliation: Rheumatology Research Center, Razi Hospital, School of Medicine, Guilan University of Medical Sciences, Rasht, Iran.
authors.forename: Asghar
authors.initials: A
authors.lastname: Hajiabbasi
authors.affiliation: Rheumatology Research Center, Razi Hospital, School of Medicine, Guilan University of Medical Sciences, Rasht, Iran.
authors.forename: Irandokht
authors.initials: I
authors.lastname: Shenavar Masooleh
authors.affiliation: Rheumatology Research Center, Razi Hospital, School of Medicine, Guilan University of Medical Sciences, Rasht, Iran.
authors.forename: Habib
authors.initials: H
authors.lastname: Zayeni
authors.affiliation: Otolaryngology and Head and Neck Surgery Research Center, Iran University of Medical Sciences, Tehran, Iran.
authors.forename: Babak
authors.initials: B
authors.lastname: Ghalebaghi
authors.affiliation: Student Research Center, Razi Hospital, School of Medicine, Guilan University of Medical Sciences, Rasht, Iran.
authors.forename: Amir
authors.initials: A
authors.lastname: Hassankhani
authors.affiliation: Department of Rheumatology, Iran University of Medical Sciences, Tehran, Iran.
authors.forename: Ali
authors.initials: A
authors.lastname: Bidari
keywords: Chronic pain syndrome; Fibromyalgia; Invalidation; Iran; Surveys and Questionnaires; Vitamin D