Thyroidectomy Decreases Snoring and Sleep Apnea: Fact or Fantasy?

I n this issue of Thyroid, Reiher and her colleagues from the University of Wisconsin report their study of snoring and sleep apnea after thyroidectomy (1). This is an interesting study in which the authors have reported the effects of thyroidectomy, based on preoperative and postoperative questionnaires, in patients who may have sleep apnea. Interestingly, the authors selected for preoperative study a group of patients who reported symptoms of obstructive sleep apnea. The authors do mention that the most effective way to evaluate sleep apnea is an overnight polysomnogram. The problem remains, however, that sleep apnea or snoring are difficult clinical issues and personal reporting may not be the most effective way to study them.

The authors included a variety of patients, among them those with thyroid cancer, Graves' disease, thyroiditis, or compressive symptoms. The number of patients with large goiters was small in this series. Patients who presented with large compressive goiters would clearly benefit from thyroidectomy, and it is quite likely the patients may have misinterpreted their symptoms due to having sleep apnea. Hypothyroid and obese patients are known to have sleep apnea (2 –4) and their symptoms may improve after surgery; however, in this study, the authors reported better results in patients who had lower thyrotropin compared with <25% improvement in patients with higher thyrotropin. This result is clearly paradoxical, and it is quite likely this erroneous impression may come from a variety of different types of patients, including some with Graves' disease. Clearly, the number of patients reported was quite small, and the findings will need to be confirmed in a larger group of patients.

Snoring is a difficult symptom to self-report. Most individuals who snore regularly do feel and argue that they rarely snore; however, their partners will attest to their snoring. Subjective information or questioning in relation to snoring may be difficult to interpret. After thyroidectomy, the natural architecture of the neck changes considerably in relation to the pharynx and esophagus, and some of the improvements in the symptoms may be related to anatomical changes in the laryngopharyngeal area rather than anything to do with sleep apnea. It should be recognized that sleep apnea is not an indication for thyroidectomy; however, thyroid pathology is a real indication for surgery. It is interesting that the authors also reported improvement in symptoms with hemithyroidectomy. The severity of patients' symptoms based on self-reporting is difficult to quantify. However, of the 33 patients who underwent total thyroidectomy and took part in the study, only seven patients had known sleep apnea and used a CPAP machine at home pre-operatively; after surgery, only one patient no longer required a CPAP. Interestingly, patients with compressive symptoms did not reveal any obvious improvement compared with those without compressive symptoms.

One of the issues about snoring bothersome to others is that it is clearly difficult for the individual to report. Sleep apnea and snoring are such vague conditions that unless the patient is quite obese or has large goiter or has been using a CPAP machine regularly, any postoperative changes in these individuals are difficult to recognize, especially based on a questionnaire. The authors rightfully commented on the small number of patients; clearly this is a good start. It may be difficult to expand this study to patients who are proven to have sleep apnea and are undergoing thyroidectomy, whether for large goiters, substernal goiters, tracheal compression, or thyroid cancer. Even though the title of the article states “thyroidectomy decreases snoring and sleep apnea symptoms,” I am not sure the study completely supports this conclusion. Further studies are necessary to distinguish fact from fantasy in this difficult area.