Department of Endocrinology & Medicine, Aalborg Hospital, Aarhus University Hospital, Aalborg, Denmark.
Clin Endocrinol (Oxf). 2012 Nov;77(5):764-72. doi: 10.1111/j.1365-2265.2012.04455.x.
Current smoking is associated with a low prevalence of thyroid autoantibodies. On the other hand, smoking withdrawal enhances thyroid autoantibody level and may be a risk factor for the development of hypothyroidism. The aim of this study was to assess the association between smoking habits (smoking cessation in particular) and development of autoimmune hypothyroidism.
Population-based, case-control study.
Cases (n = 140) newly diagnosed with primary autoimmune overt hypothyroidism were identified prospectively by population monitoring (2,027,208 person-years of observation) of all thyroid function tests performed in the two well-defined geographical areas. Individually, age-, sex- and region-matched euthyroid controls (n = 560) were simultaneously included from the same population.
Participants gave details on smoking habits including smoking withdrawal and other lifestyle factors. Smoking habits were verified by measuring urinary cotinine (a nicotine metabolite).
Incident hypothyroidism was very common in people who had recently stopped smoking: OR vs never smokers (95%-CI); quit smoking <1 years, 7·36 (2·27-23·9); 1-2 years, 6·34 (2·59-15·3); 3-10 years, 0·75 (0·30-1·87); >10 years, 0·76 (0·38-1·51). Results were consistent in both sexes and irrespective of age. Within two years after smoking cessation, the percentage of hypothyroid cases attributable to cessation of smoking was 85%. The current smoking was not associated with altered risk of developing overt hypothyroidism [OR, 0·92 (0·57-1·48)].
The risk of having overt autoimmune hypothyroidism diagnosed is more than 6-fold increased the first 2 years after cessation of smoking. Clearly, smoking cessation is vital to prevent death and severe disease. However, awareness of hypothyroidism should be high in people who have recently quit smoking, and virtually any complaint should lead to thyroid function testing.
目前的研究表明，吸烟与甲状腺自身抗体的低患病率有关。另一方面，戒烟会增加甲状腺自身抗体的水平，并可能成为甲状腺功能减退症发展的危险因素。本研究旨在评估吸烟习惯（特别是戒烟）与自身免疫性甲状腺功能减退症发展之间的关系。
基于人群的病例对照研究。
通过对两个定义明确的地理区域内进行的所有甲状腺功能检测进行人群监测（2027208 人年观察），前瞻性地确定了 140 例新诊断的原发性自身免疫性显性甲状腺功能减退症病例。年龄、性别和地区匹配的甲状腺功能正常对照者（n=560）也同时从同一人群中纳入。
参与者详细描述了吸烟习惯，包括戒烟和其他生活方式因素。吸烟习惯通过测量尿中可替宁（一种尼古丁代谢物）来验证。
近期戒烟者发生甲状腺功能减退症的情况非常常见：与从不吸烟者相比的比值比（95%可信区间）；戒烟<1 年者为 7.36（2.27-23.9）；戒烟 1-2 年者为 6.34（2.59-15.3）；戒烟 3-10 年者为 0.75（0.30-1.87）；戒烟>10 年者为 0.76（0.38-1.51）。结果在男女和年龄组中均一致。在戒烟后两年内，因戒烟而发生甲状腺功能减退症的比例为 85%。目前吸烟与显性甲状腺功能减退症发病风险增加无关[比值比，0.92（0.57-1.48）]。
在戒烟后的前 2 年内，诊断为显性自身免疫性甲状腺功能减退症的风险增加了 6 倍以上。显然，戒烟对于预防死亡和严重疾病至关重要。然而，对于近期戒烟者，应高度警惕甲状腺功能减退症，并且几乎任何症状都应进行甲状腺功能检测。
