终末潮气二氧化碳水平在亚临床和显性甲状腺功能减退症患者中低于健康对照组；与甲状腺功能检查无关。

End-tidal CO(2) levels lower in subclinical and overt hypothyroidism than healthy controls; no relationship to thyroid function tests.

机构信息

Tuberculosis and Lung Disease Research Center, Tabriz University of Medical Sciences, Tabriz, Iran.

出版信息

Int J Gen Med. 2011 Jan 7;4:29-33. doi: 10.2147/IJGM.S16252.

DOI:10.2147/IJGM.S16252

PMID:21403789

原文链接:https://pmc.ncbi.nlm.nih.gov/articles/PMC3056328/

Abstract

BACKGROUND

Hypoventilation is a frequently suspected complication of hypothyroidism.

OBJECTIVE

In this study we examined the hypothesis that changes in alveolar ventilation, as measured by end-tidal carbon dioxide (Et-CO(2)), differ between patients with mild (subclinical) and overt (clinical) thyroid hormone deficiency, and both differ from healthy control subjects.

METHODS

A total of 95 subjects, including 33 with subclinical hypothyroidism (an elevated thyroid-stimulating hormone (TSH) level and a normal thyroxin (fT(4)) level), 31 with overt hypothyroidism (elevated TSH and decreased fT(4)), and 31 healthy controls. All subjects were female and were evaluated clinically by an endocrinologist for evidence of thyroid disease and categorized on the basis of thyroid hormone levels. Et-CO(2) was measured using a capnograph. Et-CO(2) levels were measured three times and the mean value was considered as the mean level for the individual.

RESULTS

Mean Et-CO(2) values of the subclinical hypothyroidism group were significantly lower than those of the healthy controls (31.79 ± 2.75 vs 33.81 ± 2.38; P = 0.01). Moreover, mean Et-CO(2) values for the overt hypothyroidism group were significantly lower than those for healthy controls (32.13 ± 3.07 vs 33.81 ± 2.38; P = 0.04). There was a significant correlation between Et-CO(2) values and TSH levels (r = -0.24; P = 0.01). However, Et-CO(2) values were not correlated with fT(4) levels (r = 0.13; P = 0.20).

CONCLUSIONS

Alveolar ventilation, as inferred from lower Et-CO(2) levels, is higher in subjects with subclinical hypothyroidism and overt hypothyroidism (lower Et-CO(2)) than in healthy controls. Furthermore, Et-CO(2) levels have no relationship to the levels of TSH or fT(4). The lower Et-CO(2) in these patients with hypothyroidism, particularly at the subclinical stage, suggests presence of hyperventilation, which may be related to direct effect of TRH on respiratory center or to local changes within the lung.

摘要

背景

低通气是甲状腺功能减退症的常见并发症。

目的

本研究旨在检验假设，即通过测量呼气末二氧化碳（Et-CO2）来评估肺泡通气，在亚临床（亚临床）和显性（临床）甲状腺激素缺乏的患者中是否存在差异，并且与健康对照组不同。

方法

共有 95 名女性受试者，包括 33 名亚临床甲状腺功能减退症患者（促甲状腺激素（TSH）水平升高，甲状腺素（fT4）水平正常），31 名显性甲状腺功能减退症患者（TSH 升高和 fT4 降低）和 31 名健康对照组。所有受试者均由内分泌科医生进行临床评估，以确定是否存在甲状腺疾病，并根据甲状腺激素水平进行分类。使用二氧化碳描记仪测量 Et-CO2。测量 Et-CO2 水平三次，取平均值作为个体的平均值。

结果

亚临床甲状腺功能减退症组的平均 Et-CO2 值明显低于健康对照组（31.79 ± 2.75 与 33.81 ± 2.38；P = 0.01）。此外，显性甲状腺功能减退症组的平均 Et-CO2 值明显低于健康对照组（32.13 ± 3.07 与 33.81 ± 2.38；P = 0.04）。Et-CO2 值与 TSH 水平呈显著负相关（r = -0.24；P = 0.01）。然而，Et-CO2 值与 fT4 水平无相关性（r = 0.13；P = 0.20）。

结论

从较低的 Et-CO2 值推断，亚临床甲状腺功能减退症和显性甲状腺功能减退症（较低的 Et-CO2）患者的肺泡通气量高于健康对照组。此外，Et-CO2 水平与 TSH 或 fT4 水平无关。这些甲状腺功能减退症患者，尤其是亚临床阶段，较低的 Et-CO2 表明存在过度通气，这可能与 TRH 对呼吸中枢的直接作用或肺部内局部变化有关。