Is Chronic Obstructive Pulmonary Disease Associated with Alterations in Hearing? A Systematic Review and Meta-Analysis

Abstract

Background and Aims: Chronic obstructive pulmonary disease (COPD) affects up to 600 million people worldwide and it is currently one of the leading causes of morbidity and mortality in patients suffering from chronic diseases. The primary purpose of this study was to conduct a systematic review in order to explore the effects of COPD on the auditory system function by performing a quantitative analysis of currently available published data on this subject. Methods: We systematically searched seven diverse electronic databases and manual searching of references to identify relevant studies. Data from the selected studies were rated by two investigators independently in a blinded fashion. Meta-analysis was done on pooled data using Cochrane's Review Manager 5. Results: Sixteen articles received suitable scores and were thus included for further processes. Hearing loss (HL) was defined by all studies as change in pure tone audiometry (PTA) thresholds, auditory brainstem response (ABR) and auditory P300 parameters. ABR waves was significantly elongated in patients with COPD than in controls (SMD = 0.27; 95%CI: 0.05-0.48; P = 0.02). PTA was significantly higher in patients with COPD when compared with control cases (SMD = 1.76; 95%CI: 0.43-3.08; P=0.0004). We found that patients with COPD had a significantly higher latency than controls (SMD = 1.30; 95%CI: 0.79-1.80; P=0<0001). Conclusions: COPD patients had considerably greater incidence for HL when compared with controls. Interesting, although the mean PTA thresholds at every frequency for COPD patients was higher than those for controls, these values were still in the slight to mild hearing loss ranges. Prolonged ABR wave latencies in the COPD patients suggest retro-cochlear involvement. Thus COPD most frequently clusters with HL, which is worth noting that alteration in hearing is not always recognized by medical experts as frequent comorbidity associated with COPD. Funding: None Conflict of interest: None