Abstract: Objective  To understand the iodine nutritional status in Chengguan District of Lanzhou, and the epidemiological characteristics and influencing factors of thyroid nodules. Methods  Stratified cluster sampling was used to conduct a crosssectional survey on six communities. Thyroid ultrasound, thyroid function and urine iodine were tested. Results  The prevalence rate of thyroid nodules was 21.0% as a whole, with that of the men being, 17.2% and that of women being. Obviously, the prevalence rate of. women was higher than men (P<0.05).The majority of patients under 60 years had single nodules less than 1.0  cm. Patients over 60 years had multiple thyroid nodules with the diameter greater than or equal to 1.0  cm. Thyroid function in patients with thyroid nodules was normal (81.6%), and there was no association between thyroid nodules and thyroid function(P＞0.05). The median urinary iodine level in Lanzhou area was 205.4  μg/L, higher than that in other areas of China, and significantly higher in women than men (P<0.05). The urine iodine level decreased with age (P<0.05). Age is an important factor affecting the occurrence and development of thyroid nodules. Conclusion  The level of urine iodine is high in Lanzhou area. Both age and sex are related to the occurrence and development of thyroid nodules.

Key words: thyroid nodule, iodine, thyroid function tests