Persistence of goitre in children post-salt iodization in Islamic Republic of Iran: autoimmune status

We evaluated the prevalence of autoimmune thyroiditis in a random sample of 1188 schoolchildren aged 8-13 years with normalized iodine intake in the Islamic Republic of Iran. The prevalence of goitre was 39.6%; the majority had palpable but non-visible goitre. Of a subsample of 500 children, median urinary iodine excretion [18/8 microg/dL] indicated normal iodine intake. Thyroid peroxidase [TPO] antibody was positive in 3.7% of children and was significantly correlated with the prevalence of goitre and hypothyroidism. No correlation was seen between urinary iodine excretion and positive TPO antibody, mean TPO antibody, hypothyroidism or prevalence of goitre. Autoimmune thyroiditis explains some cases of goitre but other goitrogenic factors need to be evaluated

[Prevalence of autoimmune thyroiditis in school children 10 years after normalized iodine intake]

Iodine deficiency has been identified as a significant public health problem in Iran. The main strategy for control of iodine deficiency was country wide salt iodination. 10 years after starting this program, goiter is still endemic in some school children. The most important differential diagnosis is autoimmune thyroiditis. The aim of the present study was to evaluate prevalence of autoimmune thyroiditis in school children with normalized iodine intake. 1188 school children, aged 8-13 years, were selected by cluster random sampling to evaluate prevalence of goiter. From a total of 1188, 500 school children were chosen to assess urinary iodine excretion, free T4, free T3, TPO anti body [TPOAb] and TSH. Goiter was endemic in 39.6%[95% CI 36/3%-41/7%] but majority of them had grade I thyromegaly. Median urinary iodine excretion [18/8 microg/ dl] indicated normal iodine intake. Mean [95%CI] free T4, free T3 and TSH concentration were 13.1[12.8-13.3] pg/ml, 3.7[3.6-3.8]pg/ml and 2.5 [2.2-2.8] IU/ml respectively. TPOAb was positive in 3.7% of children with a higher prevalence in girls[P< 0.001]. The prevalence of hypothyroidism and hyperthyroidism was 9% and 0.2% respectively but only 0.8% of school children had TSH>10. There was a significant relationship between detection of positive TPOAb, prevalence of goiter and hypothyroidism; however no relation was seen between urinary iodine excretion status and detection of positive TPOAb, hypothyroidism and prevalence of goiter. Despite median urinary iodine excretion being normal, persistence of goiter suggested presence of goiterous factors; alhought the autoimmune mechanisms of thyroid may to some extent autoimmune of thyroid explain some part of the goiter prevalence it is however necessary to evaluate other factors

Effect of menopause and renal function on vitamin D status in Iranian women

The effects of menopause and renal function on serum parameters of the vitamin D-endocrine system were studied in a cross-sectional sample of 676 healthy women aged 20-74 years in Shiraz. Low serum 25-hydroxyvitamin D [25-OHD] was found in 52.9% of the women. Serum parathyroid hormone [PTH] increased significantly over the age span in premenopausal women [r= 0.13, P= 0.02]. In premenopausal and postmenopausal women, serum levels of 25-OHD, phosphorus and calcium were stable across the age span. There was no significant correlation between creatinine clearance or serum PTH [r= -0.016, P= 0.66] and 25-OHD [r= 0.012, P= 0.74]. The high prevalence of vitamin D deficiency warrants consideration of dietary supplementation