REVIEW OF: Marques T et al, Eur Arch Otorhinolaryngol 2021; Epub ahead of print

STUDY TYPE: Randomized open-label controlled trial

Age-related hearing loss is associated with depression, poorer physical and social functioning, and decreased quality of life, but can hearing aids reverse those trends? This study examined the effects of “aural rehabilitation” (hearing aids) on depressive symptoms.

The study randomly assigned 61 patients with moderate bilateral hearing loss to either receive a hearing aid or undergo no treatment. Blinding was not possible, and the control intervention consisted of regular follow-up without any placebo treatment. The primary outcome was the change in the Geriatric Depression Scale (GDS) at four weeks. A diagnosis of major depression was not required for study entry, but the participants entered the study with an average GDS score that was just at the cutoff for clinical depression. The patients with cognitive impairment were excluded from the study.

After four weeks, the average depression score decreased from 10.63 to 6.94 in the hearing aid group, while the score in the control group went from 11.69 to 10.97, a significant difference (p = 0.003). Using a regression model, the authors also examined the effect of various factors on depression score: age, marital status, educational level, and BPTA (a measure of hearing loss). Investigators concluded that hearing loss was independently associated with depression, and the degree of hearing loss was the main predictive factor for depressive symptoms at study entry.

The main limitation of this study is the lack of a placebo treatment in the control arm. An intervention as profound as restoration of hearing is likely to provoke a profound Hawthorne effect, a well-known phenomenon where virtually any observation or intervention can create a positive change in behavior, at least for a brief period. Other limitations include the absence of blinding, the brevity of the study, and the disparity in age between the two groups—the treatment group was younger than the control, with an average age of 77 vs 82, a significant difference (p = 0.013).

TCPR’S Take
Many of us have seen dramatic changes in our elderly patients’ functionality and demeanor with restoration of hearing, and it’s nice to see that confirmed here despite the study’s limitations. The findings serve as a reminder that we should probably investigate hearing loss more aggressively and refer for intervention when indicated.