Müller B, Zulewski H, Huber P, Ratcliffe J G, Staub J J
Department of Medicine, University Hospital, Basel, Switzerland.
N Engl J Med. 1995 Oct 12;333(15):964-9. doi: 10.1056/NEJM199510123331503.
The effect of smoking on thyroid function is controversial, and its effect on thyroid hormone action is unknown. We investigated the effects of cigarette smoking in women with various grades of hypothyroidism and in normal women.
We studied 138 normal women and 135 women with primary hypothyroidism, of whom 84 had subclinical hypothyroidism and 51 overt hypothyroidism. Sixty of the women with hypothyroidism were reevaluated during thyroxine therapy. The women were categorized as smokers or nonsmokers according to their responses to a questionnaire. Thyroid function was evaluated by measurements of serum thyrotropin, free thyroxine, and triiodothyronine. Peripheral thyroid hormone action was assessed by a clinical score and measurements of ankle-reflex time and serum lipids and creatine kinase.
Among the women with subclinical hypothyroidism, the smokers had a higher mean (+/- SD) serum thyrotropin concentration (21.3 +/- 16.6 vs. 12.7 +/- 7.2 mU per liter, P = 0.004) and a higher ratio of serum triiodothyronine to serum free thyroxine (by 30 percent, P = 0.003) than the nonsmokers. Their serum concentrations of total cholesterol and low-density lipoprotein (LDL) cholesterol were higher (by 16 percent, P = 0.013; and 28 percent, P = 0.003, respectively). Among the women with overt hypothyroidism, the serum concentrations of thyrotropin, free thyroxine, and triiodothyronine were similar in the smokers and nonsmokers. As compared with the nonsmokers, the smokers had a clinical score indicating a greater degree of hypothyroidism (P < 0.001), higher serum concentrations of total and LDL cholesterol (by 25 percent, P < 0.001; and 24 percent, P = 0.002, respectively), longer ankle-reflex time (by 25 percent, P < 0.001), and higher serum concentrations of creatine kinase (by 236 percent, P < 0.001). There were dose-response relations between smoking and serum concentrations of total and LDL cholesterol, serum creatine kinase concentrations, and ankle-reflex time in the women with overt hypothyroidism, and between smoking and serum concentrations of total and LDL cholesterol in the women with subclinical hypothyroidism.
Smoking increases the metabolic effects of hypothyroidism in a dose-dependent way. This may be explained by alteration of both thyroid function and hormone action.
吸烟对甲状腺功能的影响存在争议，其对甲状腺激素作用的影响尚不清楚。我们研究了吸烟对不同程度甲状腺功能减退女性及正常女性的影响。
我们研究了138名正常女性和135名原发性甲状腺功能减退女性，其中84名患有亚临床甲状腺功能减退，51名患有显性甲状腺功能减退。60名甲状腺功能减退女性在接受甲状腺素治疗期间进行了重新评估。根据她们对问卷的回答将这些女性分为吸烟者或非吸烟者。通过测量血清促甲状腺激素、游离甲状腺素和三碘甲状腺原氨酸来评估甲状腺功能。通过临床评分以及测量踝反射时间、血清脂质和肌酸激酶来评估外周甲状腺激素作用。
在亚临床甲状腺功能减退女性中，吸烟者的平均（±标准差）血清促甲状腺激素浓度较高（21.3±16.6对12.7±7.2 mU/升，P = 0.004），血清三碘甲状腺原氨酸与血清游离甲状腺素的比值也较高（高30%，P = 0.003）。她们的血清总胆固醇和低密度脂蛋白（LDL）胆固醇浓度较高（分别高16%，P = 0.013；和28%，P = 0.003）。在显性甲状腺功能减退女性中，吸烟者和非吸烟者的促甲状腺激素、游离甲状腺素和三碘甲状腺原氨酸的血清浓度相似。与非吸烟者相比，吸烟者的临床评分显示甲状腺功能减退程度更严重（P < 0.001），血清总胆固醇和LDL胆固醇浓度更高（分别高25%，P < 0.001；和24%，P = 0.002），踝反射时间更长（长25%，P < 0.001），血清肌酸激酶浓度更高（高236%，P < 0.001）。在显性甲状腺功能减退女性中，吸烟与血清总胆固醇和LDL胆固醇浓度、血清肌酸激酶浓度以及踝反射时间之间存在剂量反应关系，在亚临床甲状腺功能减退女性中，吸烟与血清总胆固醇和LDL胆固醇浓度之间存在剂量反应关系。
吸烟以剂量依赖的方式增加甲状腺功能减退的代谢效应。这可能是由甲状腺功能和激素作用的改变所解释的。
