背景：近期研究显示，不明原因的慢性咳嗽与阻塞性睡眠呼吸暂停（OSA）有关。目前的指南推荐采用经验性综合治疗措施来治疗慢性咳嗽，特别是胃食管反流（GERD）诱发的咳嗽、上呼吸道咳嗽综合征（UACS）和咳嗽变异性哮喘（CVA）。但对OSA的检测未做任何推荐。本试验旨在研究因慢性咳嗽就诊的患者中的OSA发病率，研究OSA治疗对缓解慢性咳嗽的有效性。 
    方法：过去4年中，对社区肺部疾病诊疗中的慢性咳嗽患者进行回顾性研究。排除胸片异常、肺功能检测异常、已有肺间质性疾病和随访不全的患者。基于病历回顾，对临床数据、给予的治疗、咳嗽缓解程度进行评价。特别是对OSA患者进行诊断性检测，同时评估OSA治疗对慢性咳嗽的影响。
    结果：75名患孤立性慢性咳嗽的患者入选本项研究。其中44名患者有明确的咳嗽病因（GERD 占37%, UACS 占12%, CVA 占8%）。31名患者的咳嗽症状具有多发病因（GERD-UACS 占31%, GERD-CVA 占5%, UACS-CVA占3%, GERD-UACS-CVA占3%）。31%的患者进行了进一步诊断性检测，评价UACS、GERD和CVA。对38名患者进行针对OSA的特异性检查，在其中33名患者中发现存在阻塞性睡眠呼吸暂停。在接受针对睡眠呼吸异常治疗的患者中，93％患者的咳嗽症状得到改善。
    结论：慢性咳嗽患者常同时存在OSA，同样也可能存在其他咳嗽病因。CPAP疗法联合针对咳嗽症状的其他特异性治疗措施能改善咳嗽严重程度。有必要在慢性咳嗽管理中增加对睡眠呼吸暂停的评价和治疗。 

Chronic cough and obstructive sleep apnea in a community-based pulmonary practice.

Sundar KM, Daly SE, Pearce MJ, Alward WT.

Abstract

BACKGROUND: Recent reports suggest an association between unexplained chronic cough and obstructive sleep apnea (OSA). Current guidelines provide an empiric integrative approach to the management of chronic cough, particularly for etiologies of gastroesophageal reflux (GERD), upper airway cough syndrome (UACS) and cough variant asthma (CVA) but do not provide any recommendations regarding testing for OSA. This study was done to evaluate the prevalence of OSA in patients referred for chronic cough and examine the impact of treating OSA in resolution of chronic cough.

METHODS: A retrospective review of chronic cough patients seen over a four-year period in a community-based pulmonary practice was done. Patients with abnormal chest radiographs, abnormal pulmonary function tests, history of known parenchymal lung disease, and inadequate followup were excluded. Clinical data, treatments provided and degree of resolution of cough was evaluated based on chart review. Specifically, diagnostic testing for OSA and impact of management of OSA on chronic cough was assessed.

RESULTS: 75 patients with isolated chronic cough were identified. 44/75 had single etiologies for cough (GERD 37%, UACS 12%, CVA 8%). 31/75 had multiple etiologies for their chronic cough (GERD-UACS 31%, GERD-CVA 5%, UACS-CVA 3%, GERD-UACS-CVA 3%). 31% patients underwent further diagnostic testing to evaluate for UACS, GERD and CVA. Specific testing for OSA was carried out in 38/75 (51%) patients and 33/75 (44%) were found to have obstructive sleep apnea. 93% of the patients that had interventions to optimize their sleep-disordered breathing had improvement in their cough.

CONCLUSIONS: OSA is a common finding in patients with chronic cough, even when another cause of cough has been identified. CPAP therapy in combination with other specific therapy for cough leads to a reduction in cough severity. Sleep apnea evaluation and therapy needs to considered early during the management of chronic cough and as a part of the diagnostic workup for chronic cough.