McElvaney G N, Wilcox P G, Fairbarn M S, Hilliam C, Wilkins G E, Pare P D, Pardy R L
University of British Columbia Pulmonary Research Laboratory, St. Paul's Hospital, Vancouver, Canada.
Am Rev Respir Dis. 1990 May;141(5 Pt 1):1221-7. doi: 10.1164/ajrccm/141.5_Pt_1.1221.
Dyspnea on exertion is a frequently reported symptom of thyrotoxicosis. In the majority of cases, there is no obvious cause of dyspnea, but as skeletal myopathy is also common in thyrotoxic patients, it has been postulated that increased dyspnea could be secondary to respiratory muscle weakness. We sought to determine whether thyrotoxic patients were in fact more dyspneic on exertion than age- and sex-matched controls, and if so, whether the increased dyspnea was secondary to respiratory muscle weakness. The study group consisted of 12 thyrotoxic patients and 12 control subjects matched for age and gender. We measured lung volumes, compliance, elastic recoil, respiratory muscle strength, maximal exercise performance, and the intensity of breathlessness (modified Borg scale) at various levels of exercise in all subjects. The respiratory muscles were weaker in patients than controls. This weakness improved in treated patients (p less than 0.05) with concomitant increases in VC, IC, and TLC (all p less than 0.05). Despite this, we found no differences in breathlessness intensity scores between patients and controls or in patients before and after successful antithyroid therapy.
劳力性呼吸困难是甲状腺毒症常见的症状。在大多数情况下，呼吸困难并无明显原因，但由于骨骼肌病在甲状腺毒症患者中也很常见，因此有人推测呼吸困难加重可能继发于呼吸肌无力。我们试图确定甲状腺毒症患者在运动时是否比年龄和性别匹配的对照组更容易出现呼吸困难，如果是，呼吸困难增加是否继发于呼吸肌无力。研究组由12名甲状腺毒症患者和12名年龄和性别匹配的对照者组成。我们测量了所有受试者在不同运动水平下的肺容量、顺应性、弹性回缩力、呼吸肌力量、最大运动能力以及呼吸困难强度（改良Borg量表）。患者的呼吸肌比对照组弱。在接受治疗的患者中，这种肌无力情况有所改善（p<0.05），同时肺活量（VC）、吸气量（IC）和肺总量（TLC）均增加（均p<0.05）。尽管如此，我们发现患者与对照组之间的呼吸困难强度评分没有差异，成功进行抗甲状腺治疗前后的患者之间也没有差异。
