title: Vitamin d deficiency and its association with thyroid disease.
abstract: OBJECTIVE
  Vitamin D deficiency is a global health problem, its role as an immune modulator has been recently emphasized. The evidence is increasingly pointing towards vitamin D significant role in reducing the incidence of autoimmune diseases. However, at this time the research on its role in autoimmune and thyroid disease is not conclusive. We aimed to examine the relationship between hypothyroidism and vitamin D deficiency and to clarify the relation between serum calcium levels with hypothyroid disease.
  
  
  METHODS
  Serum vitamin D (25-OH) levels were measured in 30 patients with hypothyroidism and 30 healthy subjects, utilizing the spectrophotometric method. Vitamin D deficiency was designated at levels lower than 20 ng/ml. Thyroid hormones (TSH, T3 and T4) and calcium levels were evaluated in all participants.
  
  
  RESULTS
  Serum 25(OH) vit D was significantly lower in hypothyroid patients than in controls (t=-11.128, P =0.000). Its level was insignificantly decreased in females than male patients (t=- 1.32, P >0.05). Moreover, serum calcium levels recorded a significant decrease in hypothyroid patients when compared to controls (t= -5.69, P = 0.000).
  
  
  CONCLUSIONS
  Our results indicated that patients with hypothyroidism suffered from hypovitaminosis D with hypocalcaemia that is significantly associated with the degree and severity of the hypothyroidism. That encourages the advisability of vit D supplementation and recommends the screening for Vitamin D deficiency and serum calcium levels for all hypothyroid patients.
authors.affiliation: Assistant Professor of Medical Biochemistry, Medical Laboratory Department, Applied Medical Science College, Qassim University, Saudi Arabia.
authors.forename: Amal Mohammed Husein
authors.initials: AM
authors.lastname: Mackawy
authors.affiliation: Students in the Medical Laboratory Department, Applied Medical Science College, Qassim University, Saudi Arabia.
authors.forename: Bushra Mohammed
authors.initials: BM
authors.lastname: Al-Ayed
authors.affiliation: Students in the Medical Laboratory Department, Applied Medical Science College, Qassim University, Saudi Arabia.
authors.forename: Bashayer Mater
authors.initials: BM
authors.lastname: Al-Rashidi
keywords: Blood calcium levels; Thyroid diseases; Vit D deficiency