[Changes of thyroid function, thyroid antibodies and urinary iodine among permanent residents of Urumqi in Xinjiang].

OBJECTIVE: To understand the rates of diagnosis on thyroid disease and the differences in the distribution of age groups among those permanent residents, to analyze the relationships among thyroid function, thyroid antibodies and urinary iodine.

METHODS: A cross-sectional survey was performed in 1 995 permanent residents in Urumqi, Xinjiang in May, 2013, Among them, 1 906 were healthy adults aged 18-84 age, with mean age as (46.3 ± 14.2) years and 30.4% of them were men. One time 10 ml random urine and blood samples were drown to examine urinary iodine (UI) thyroid stimulating hormone (TSH), free thyroxine (FT4), free triiodothyronine (FT3), anti-thyroglobulin (TgAb) and anti-thyroid peroxidase (TPOAb).

RESULTS: 1) 213 residents were newly diagnosed as having thyroid dysfunction (11.2%, including 78.4% women), hyperthyroidism (clinical and subclinical hyperthyroidism) that accounted for 2.7%, hypothyroidism (clinical and subclinical hypothyroidism) was accounted for 8.5%. Positive rates of TgAb (23.2%), TPOAb (16.6%) were noticed. The median urinary iodine was 134.5 µg/L, with 32% of the subjects were having iodine deficiency, 58% having adequate iodine and another 10% as under excessive iodine. No differences were observed on urine iodine between thyroid dysfunction and euthyroidism or between subjects with positive and negative antibodies. 2) TSH appeared different among age-groups of 18-, 45- and over 60. TSH showed higher in women than in men, with P value as < 0.001. For people with euthyroidism, TSH level in the antibody positive group was significantly higher than the antibody negative group (P < 0.000 1). 3) For people over 60 of age, morbidity of hypothyroidism was significantly higher than those under 60 but with no differences related to hyperthyroidism or the antibody positive rate.

CONCLUSION: UI levels were not significantly related with thyroid function and thyroid antibodies among residents of Urumqi, women showed higher on thyroid dysfunction or the rate of positive antibody. In the antibody positive group, TSH levels were significantly higher than in the antibody negative group. Hypothyroidism was seen higher in the over 60-years-of-age population. Monitoring programs on thyroid function, thyroid antibodies and urinary iodine among people over 60-years-of-age, should be strengthened.