Preplanned Studies: Hearing Loss and Depressive Symptoms Among Community-Dwelling Older Adults — Liaoning, Henan, and Guangdong Provinces, China, 2019–2020

Hearing loss (HL), a highly prevalent and undertreated disorder in older adults, affects over 60% of the elderly population in China (1). A national survey in China revealed that older adults have a higher prevalence of depression compared to other age groups (2). HL significantly impacts communication and participation in social activities, potentially leading to social isolation and negatively affecting physical and mental health. Furthermore, research suggests that HL increases the risk of depression (3). Scinicariello’s study demonstrated age and gender disparities in the association between moderate to severe HL and depressive symptoms among older adults in the United States (4). However, there is limited research on this association in older Chinese adults. This study aims to explore the relationship between severe or profound HL and depressive symptoms in the general population, focusing on age and gender differences. Data were obtained from the Prevention and Intervention on Neurodegenerative Disease for Elderly in China (PINDEC) project, which focuses on building capacity for the prevention and intervention of Alzheimer’s disease (AD) and Parkinson’s disease (PD), as well as other health conditions. This study included 9,865 community-dwelling older adults aged 60 years and older from three provinces in China. The results indicate that younger elderly individuals aged 60–74 are a high-risk group for the association between severe or profound HL and depressive symptoms. Additionally, there is a significant correlation between severe or profound HL and depressive symptoms among elderly women aged 60–74. This study shows that elderly people with severe or profound HL have a significantly increased risk of depressive symptoms. Therefore, developing a national strategy for preventing and managing HL in the elderly population is crucial to reducing the risk of depressive symptoms.

The PINDEC project considered both the degree of aging and balanced geographical distribution when initiating its 2019–2020 survey of community-based residents aged 60 and above in three regions: Liaoning, Henan, and Guangdong provinces. The stratified multi-stage cluster sampling process involved several steps. First, two or three cities were randomly selected from each province. Second, one county and one district were randomly selected from each city. Third, one subdistrict in urban areas and one township in rural areas were selected from each county/district using probability proportionate to size sampling. Finally, 4–8 administrative villages or neighborhood communities were randomly selected from each subdistrict/township using cluster sampling until the desired sample size (1,000 participants) was reached. A total of 12,369 older adults aged 60 and above were initially included (5). After excluding participants with missing key variables or who refused to participate in psychological questionnaires and hearing tests, 9,865 respondents remained in the study (Supplementary Figure S1). The study was approved by the Ethnics Committee of the National Center for Chronic and Non-Communicable Disease Control and Prevention, China CDC (Ref. no.: 201902). All participants were assigned informed consent forms.

HL was measured using the four-frequency air conduction pure-tone average (PTA) in the better ear at 500, 1,000, 2,000, and 4,000 Hz and reported continuously in decibels (dB). Lower hearing thresholds indicated better hearing, while higher thresholds indicated worse hearing. HL severity was defined using the following categories: normal HL (0 to 25 dB), mild HL (26 to 40 dB), moderate HL (41 to 60 dB), and severe or profound HL (61 dB or worse) (6). The Patient Health Questionnaire-9 (PHQ-9) was used to screen for depressive symptoms. PHQ-9 scores range from 0 to 27, and participants with scores of 5 or above were identified as having depressive symptoms (7).

Categorical variables were described using frequencies and proportions. Differences between subgroups were analyzed using the chi-square test. Multivariable logistic regression models were used to assess the association between depressive symptoms and HL, adjusting for covariates (demographic variables, behavioral factors, and cardiovascular disease). Statistical significance was set at P<0.05. All statistical analyses were performed using R software (Version 4.0.5; R Foundation for Statistical Computing, Vienna, Austria).

A total of 9,865 adults (mean age: 68.92±6.46 years) were included in this study (Table 1). Of these, 1,640 (16.62%) met the criteria for depressive symptoms. The prevalence of depressive symptoms was 15.12%, 16.47%, 18.22%, and 23.00% for participants with normal HL, mild HL, moderate HL, and severe or profound HL, respectively (P<0.001).

As HL severity increased, a statistically significant trend toward higher levels of depressive symptoms emerged in both male and female older adults (P<0.001). However, when stratified by age and gender, a progressively higher rate of depressive symptoms with increasing HL was observed only among women aged 60–74 years (Table 2).

Multivariable logistic regression analyses revealed a significant association between severe or profound HL and depressive symptoms after adjusting for multiple variables [odds ratio (OR): 1.52, 95% confidence interval (CI): 1.15, 2.01]. This association was also observed among participants aged 60–74 years (OR: 1.50, 95% CI: 1.04, 2.16). Stratified by gender, the OR for severe or profound HL was 1.56 (95% CI: 1.00, 2.43) for males in the whole population and 1.60 (95% CI: 1.01, 2.56) for females in the 60–74 age group (Table 3).