Study on the correlation between smoking and hypothyroidism in iodine-suitable areas / 中华内分泌代谢杂志

ABSTRACT

Objective To explore the relationship between different smoking status and hypothyroidism in six iodine-suitable areas of China. Methods A total of 8187 residents were investigated by cluster sampling in six cities, and 7448 residents were included in the survey. The height, weight, waist circumference, and blood pressure were measured by filling out epidemiological questionnaire. Blood samples were collected to detect thyroid stimulating hormone ( TSH) , thyroid peroxidase antibody ( TPOAb) , and thyroglobulin antibody ( TgAb) . Results The mean TSH, TPOAb, and TgAb positive rates in passive smoking and active smoking groups were all lower than those in non-smoking group ( all P<0.01) . In the active smoking group, the TSH value decreased by 0.023 units for every unit increase in smoking index. The positive rates of TgAb and TPOAb in both passive smoking and active smoking groups were lower than those in non-smoking group (all P<0.01). Active and passive smoking reduced the prevalence of hypothyroidism (both P<0.01). Among women, the risks of clinical hypothyroidism and subclinical hypothyroidism were reduced in both active and passive smoking groups. Besides, the risk of subclinical hypothyroidism decreased significantly when the smoking index was more than 70. In male population, the risk of subclinical hypothyroidism in active and passive smoking group decreased. Besides, the risk of clinical hypothyroidism and subclinical hypothyroidism decreased significantly when the smoking index was more than 70. Conclusion Smoking in iodine-suitable areas may reduce TSH level and the positive rates of TPOAb and TgAb.