不同碘摄入量对甲状腺肿和甲状腺结节影响的前瞻性研究

目的 研究不同碘摄入量人群非毒性甲状腺肿(甲肿)和非毒性甲状腺结节的流行病学特点及影响其发生、发展和转归的因素.方法 2004年对盘山(长期轻度碘缺乏)、彰武(碘缺乏基础上补碘至碘超足量)和黄骅(长期碘过量)社区于1999年参加本课题组流行病学研究并进行甲状腺B超检查的人群(3 385人)进行甲状腺疾病的随访调查.结果 (1)盘山、彰武和黄骅社区弥漫型甲肿的累积发病率分别为7.1%、4.4%和6.9%,盘山和黄骅均显著高于彰武(均P<0.01);结节型甲肿的累积发病率分别为5,0%、2.4%和0.8%,盘山的发病率最高(P<0.01).(2)三社区甲状腺单发结节的累积发病率分别为4.0%、5.7%和5.6%,多发结节的累积发病率分别为0.4%、1.2%和1.0%.(3)基础碘缺乏、碘过量、甲状腺自身抗体(thyroid autoantibody,TAA)阳性是甲肿发生的独立危险因素.(4)彰武初访时TAA阳性人群非毒性甲肿的发生率显著高于TAA阴性人群(P<0.01),盘山和黄骅无显著差异.(5)三社区非毒性弥漫型甲肿维持人群和黄骅非毒性结节型甲肿维持人群随访前后TAA阳性率均高于同社区正常人群(P<0.05).结论 碘缺乏和碘过量均有可能使甲肿的发病率增加.碘缺乏社区结节型甲肿高发,弥漫型甲肿是碘过量社区甲肿发牛的主要形式.甲状腺自身免疫与甲肿的发生和维持相关,这种相关性在历史上为碘缺乏而后过度补碘的社区更明显.

Prospective study on the effect of different iodine intakes on goiter and thyroid nodules

Objective To investigate the epidemiological characteristics of non-toxic goiter and non-toxic thyroid nodules in the regions with different iodine intakes and the factors influencing the occurrence, development and outcome of goiter and thyroid nodules. Methods 3 385 subjects, who had taken part in the previous survey in 1999 with the ultrasonic examination of thyroid, were composed of individuals in Panshan with chronic mild iodine deficiency,in Zhangwu with more than adequate iodine "after iodine supplementation and in Huanghua with excessive iodine. These 3 groups of subjects were followed up in 2004. Results (1) The cumulative incidences of diffuse goiter in Panshan ,Zhangwu and Huanghua were 7.1% ,4.4% and 6.9% ,respectively ,being the lowest in Zhangwu (P<0.01) and those of nodular goiter were 5.0% ,2. 4% and 0.8%, respectively, being the highest in Panshan (P<0.01). (2) The incidences of single nodule were 4.0% ,5.7% and 5.6%, respectively, and those of multiple nodules 0.4%, 1.2% and 1.0%, respectively. (3)The result of logistic analysis showed that iodine deficiency,iodine excess and positive thyroid autoantibodies (TAA) were the independent risk factors for the occurrence of goiter. (4)In Zhangwu ,the incidence of non-toxic goiter in the group with positive TAA was higher than that in the group with negative TAA(P<0.01) ,while there were no such differences in Panshan and Huanghua. (5)In these three regions, the rates of positive TAA in the individuals with diffuse non-toxic goiter were higher than those in the healthy subjects (P<0.05). And in Huanghua,the rate of positive TAA in subjects with non-toxic nodular goiter was also higher than that in the healthy individuals (P<0.05). Conclusion Iodine deficiency and iodine excess may both induce the raising incidence of goiter. Nodular goiter is prevalent in iodine deficient district and diffuse goiter is the predominant form in places with iodine excess. Thyroid autoimmunity is associated with occurrence and maintenance of goiter, and this phenomenon is more obvious in the community with previous iodine deficiency followed then by treatment with more than adequate iodine.