Iodine also promotes follicular cell apoptosis and has an influence on immune cells (augmented maturation of dendritic cells, increased number of T cells, stimulated B-cell immunoglobulin production).Data from The Danish Investigation of Iodine Intake and Thyroid Disease shows that within two cohorts (males, females) with moderate and mild iodine deficiency, the levels of both thyroid peroxidase and thyroglobulin antibodies are higher in females, and prevalence rates of both antibodies increase with age. Sex
Study of healthy Danish twins divided to three groups (monozygotic and dizygotic same sex, and opposite sex twin pairs) estimated that genetic contribution to thyroid peroxidase antibodies susceptibility was 61% in males and 72% in females, and contribution to thyroglobulin antibodies susceptibility was 39% in males and 75% in females.The high female predominance in thyroid autoimmunity may be associated with the X chromosome. It contains sex and immune-related genes responsible for immune tolerance. A higher incidence of thyroid autoimmunity was reported in patients with a higher rate of X chromosome monosomy in peripheral white blood cells.Another potential mechanism might be skewed X-chromosome inactivation, leading to the escape of X-linked self-antigens from presentation in the thymus and loss of T-cell tolerance.Having other autoimmune diseases is a risk factor for developing Hashimotos thyroiditis, and the opposite is also true.
Populations that are spread out or defined poorly may skew data in unexpected ways.Iodine Deficiency Disorder (IDD) is combated using an increase in iodine in a persons diet. When a dramatic change occurs in a persons diet, they become more at-risk of developing hypothyroidism and other thyroid disorders. Combatting IDD with high salt intakes should be done carefully and cautiously as risk for Hashimotos may increase. If making modifications to ones diet, it is important to use a clinicians discretion to ensure that the dietary changes are the best option as recommendations can vary person to person. Secular trends
The secular trends of hypothyroidism reveal how the disease has changed over the course of time given changes in technology and treatment options. Even though ultrasound technology and treatment options have improved, the incidence of hypothyroidism has increased according to data focused on the US and Europe. Between 1993 and 2001, per 1000 women, the disease was found varying between 3.9 and 4.89. Between 1994 and 2001, per 1000 men, the disease increased from 0.65 to 1.01.Changes in the definition of hypothyroidism and treatment options modify the incidence and prevalence of the disease overall. Treatment using levothyroxine is individualized, and therefore allows the disease to be more manageable with time but does not work as a cure for the disease.