Factors associated with generalized anxiety disorder in Korean older adults: A secondary data analysis of the 2022 Korea National Health and Nutrition Examination Survey
Article information
Abstract
Purpose
The purpose of this study is to identify the factors influencing generalized anxiety disorder (GAD) in older adults and to provide effective health management directions for GAD patients.
Methods
This study used data from the 9th National Health and Nutrition Survey (2022) and selected 1,666 older adults. The analysis was conducted using the SPSS 26.0 program. A complex sample chi-square test was performed to identify factors related to GAD. Complex sample logistic regression was conducted to determine the factors influencing GAD in the participants.
Results
The study results indicated that sex (p=.034), smoking (p=.042), alcohol consumption (p=.003), sleep duration (p=.005), chewing discomfort (p<.001), speaking discomfort (p<.001), and self-rated health (p=.016) were statistically significantly associated with GAD. The multivariate analysis considering the interaction between variables, sleep duration (OR=2.07, p=.031) and chewing discomfort (OR=2.49, p=.008) were identified as factors influencing GAD.
Conclusion
Chewing discomfort in older adults affects not only GAD but also leads to a decline in aesthetics and social withdrawal. Therefore, improvements in oral health policy support for oral health promotion and prevention are required. Additionally, education and interventions through community systems should be provided to address sleep issues associated with GAD.
INTRODUCTION
Older adulthood involves experiencing physical and mental challenges, including functional decline, withdrawal from economic activity, and the loss of a spouse [1]. Nevertheless, the economic resources and social support systems that are in place to assist individuals in coping with these transitions are frequently found to be inadequate [2]. Physical health issues among older adults, such as age-related decline in bodily functions and increased prevalence of chronic diseases, along with social loss and isolation, economic hardship, cognitive decline, and psychological stress, precipitate generalized anxiety disorder (GAD) [3]. GAD is a condition that is characterized by excessive anxiety or worry that persists for a minimum of 6 months, accompanied by a multitude of concerns that are challenging to regulate. These concerns are often accompanied by various physical and mental symptoms, including restlessness, muscle tension, fatigue, sleep disturbances, and impaired concentration [4]. However, the presence of other mental disorders makes it difficult to diagnose GAD. This leads to a high probability that the severity of the disorder will be overlooked, necessitating systematic management [5].
As population aging accelerates in South Korea, mental health concerns among older adults are coming to the fore, emerging as a pressing social priority that is comparable to the prevalence of physical health issues. Because worry, tension, and anxiety are often considered secondary symptoms of depression among older adult patients, the symptoms of GAD are likely to be overlooked. Therefore, careful attention to anxiety symptoms among older adults is warranted, independently of depressive symptoms [5], highlighting the importance of systematic management for the early detection and treatment of mental health issues in this population. However, most research on the mental health of older adults focuses on topics such as depression, suicide, and death; few studies have examined GAD.
Previous studies [3,6,7] have reported an association between GAD and stressors. Older adults demonstrate a heightened vulnerability to exacerbated GAD symptoms, which is attributable to a multitude of stressors, including physical, psychological, and socioeconomic factors, as well as apprehensions regarding death, stemming from developmental characteristics. Furthermore, older adults perceived health-related stress to be the most significant form, and this perceived stress was found to directly influence anxiety [2]. This high level of stress is closely associated with GAD [3,7]. Self-rated health (SRH) [7] and sleep disorders among older adults are also reportedly associated with GAD [8]. This anxiety among older adults has been associated with negative factors such as functional decline, cognitive impairment, and reduced quality of life [8]. In other words, even when older adults experience equivalent levels of stress, their degree of anxiety may vary according to the manner in which it is perceived by the individual, and since higher levels of social support reduce stress [1], efforts by both the individual and their circle are indispensable for developing the capacity to regulate stress.
Meanwhile, oral health can impair GAD. Oral health issues, including chewing discomfort, tooth loss, and the use of removable dentures, reportedly affect mental health conditions such as GAD among older adults [7,9,10]. Periodontal disease is the result of a complex interplay between bacterial growth and the host immune system. The extant literature has demonstrated that periodontal disease is associated with stress factors, including stress related to the health of the individual and that of their family members [11]. Adults diagnosed with depression or anxiety disorders exhibit an elevated risk of tooth loss when compared with adults not afflicted with such conditions [9], which substantiates the established correlation between oral health and mental/psychological factors. In addition, elevated scores on the GAD-7 scale have been correlated with more pessimistic self-perceptions of oral health status [12]. Moreover, oral health concerns have been demonstrated to result in restrictions on social activities and influence social interactions [12,13]. These oral health concerns can also diminish the quality of life of older adults by impeding chewing, speech, and aesthetic functions [14]. To reduce the prevalence of GAD and enhance the quality of life among those affected, the mental/psychological, sociocultural, physical, and cognitive factors associated with GAD must be identified.
Since 1998, South Korea has administered the Korea National Health and Nutrition Examination Survey (KNHANES) to establish a Health Plan that is based on nationally representative and reliable data on the health status and behaviors of its citizens. Notably, surveys on stress and suicide-related issues have been conducted since 1998. However, the survey for diagnosing GAD began in 2021, resulting in a severe lack of related research. This study aims to determine the factors that influence the development of GAD among Korean older adults and propose effective health management strategies for patients with GAD.
The specific objectives are as follows.
First, the demographic characteristics, health status, and GAD severity of the subjects are assessed.
Second, the differences in GAD based on the characteristics of the subjects are identified.
Third, the factors influencing GAD among the subjects are identified.
METHODS
Ethics Statement: This study was approved by the Public Institutional Review Board (PIRB) (Approval Number: 2018-01-03-4C-A) and subsequently by the Institutional Review Board (IRB) of Kyungdong University (IRB-1041455-202502-HR-001-01). Top-coding, bottom-coding, and recategorization methods were applied to the KNHANES IX-1 (2022) data to ensure the anonymity and confidentiality of personal information. Data were provided after the researcher received approval for data use in accordance with the Korea Disease Control and Prevention Agency’s raw data disclosure and management regulations.
1. Study Design
This study adhered to the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) guidelines (http://www.strobe-statement.org). It used raw data from KNHANES IX-1 (2022). The KNHANES data are considered a public resource, as stipulated by the ‘National Health Promotion Act,’ which establishes the framework for the survey and subsequent disclosure of information on various health behaviors, the prevalence of chronic diseases, and the nutritional and dietary intake status of the population. Since the sample design used two-stage stratified cluster sampling, rather than simple random sampling, a descriptive cross-sectional study using secondary data was planned.
2. Subjects
The KNHANES household sample excluded facilities such as nursing homes, military bases, prisons, and foreign households. Within the selected sample households, all members who met the appropriate household member criteria were designated as subjects for this study. KNHANES IX-1 included a total of 6,265 individuals. This study sampled 1,666 older adults aged 65 and above from the entire population based on the objectives of the research. After the exclusion of 53 individuals with missing responses for the dependent variable (GAD-7), the final sample size for the analysis comprised 1,613 individuals (Figure 1).
Research subject selection process. GAD-7=Generalized anxiety disorder-7; KNHANES IX=9th Korea National Health and Nutrition Examination Survey.
3. Measures and Scales
1) Demographic Characteristics
The demographic characteristics of the research subjects were determined by establishing variables including sex, age, education level, and income level. Set sex categories were “male” and “female”; age categories were “65~74” and “75 and older”; income levels were “high,” “upper-middle,” “lower-middle,” and “low”; and education levels were “elementary school,” “middle school,” “high school,” and “college or above.”
2) Health Characteristics
The health characteristics of the subjects were identified as “smoking,” “alcohol consumption,” “sleep duration,” “chewing discomfort,” “speaking discomfort,” and “SRH.” The smoking variable was set to “no” for “past smoker or non-smoker” and “yes” for “current smoker.” For the alcohol consumption question, “non-drinker (lifetime) or less than one drink per month in the past year” was defined as “no,” and “one or more drinks per month in the past year” as “yes.” A sleep duration of “7~9 hours” was defined as “adequate,” while less than 7 hours or more than 9 hours was classified as “insufficient/excessive.” Chewing discomfort and speaking discomfort were scored on a 5-point scale: “very uncomfortable,” “uncomfortable,” “neutral,” “not uncomfortable,” and “not at all uncomfortable.” Responses of “very uncomfortable” or “uncomfortable” were classified as “yes,” while “neutral,” “not uncomfortable,” and “not at all uncomfortable” were classified as “no.” SRH was categorized into five levels: “very good,” “good,” “neutral,” “poor,” and “very poor.” Responses of “very good” or “good” were categorized as “good,” while “neutral,” “poor,” and “very poor” were categorized as “poor.”
3) Severity of GAD
The severity of GAD was assessed using the Korean version of the GAD-7 scale. The GAD-7 is a questionnaire developed for screening GAD, with each item scored from 0 to 3 points based on the severity of symptoms. The total score is calculated by adding the scores of all seven items, with a maximum total score of 21 points. A score of 0~4 points is classified as normal, 5~9 points as mild, 10~14 points as moderate, and 15 points or higher as severe anxiety. This scale is a self-report questionnaire and does not constitute a psychiatric diagnosis. In this study, scores of 10 or higher were considered indicative of GAD [15].
4) Data Collection
The data utilized in this study were obtained from publicly available sources and disseminated for general use. This study employed anonymized data in the form of unique identifiers that precluded personal identification, obtained through the KNHANES website (https://knhanes.kdca.go.kr/knhanes/main.do) operated by the Korea Disease Control and Prevention Agency (KDCA). Furthermore, the raw data are publicly available to the general public through the KNHANES website (https://knhanes.kdca.go.kr/) of the KDCA.
4. Analysis Method
Data were analyzed using the SPSS Statistics 26.0 program (IBM Corp., Armonk, NY, USA). The significance level was set at .05 to test the statistical significance of the research hypotheses. The weights employed in this study were derived according to the KNHANES data guidelines, and the analysis was conducted with the explicit assurance that any missing values were deemed valid.
The analysis employed a complex sample chi-square test to examine factors related to GAD based on the general characteristics of the subjects. Factors influencing the GAD of the subjects were analyzed using complex sample logistic regression.
RESULTS
1. Subject Characteristics
An analysis of the demographic characteristics, health status, and GAD characteristics of individuals aged 65 and older revealed that 3.9% had GAD. Most respondents were female (55.9%), had an education level of elementary school or below (46.4%), and reported having a “low” income (41.0%). Not smoking (90.5%), drinking alcohol (66.9%), and having “adequate” sleep duration (54.6%) received a high number of responses. A large number of responses indicated “no” chewing discomfort (66.4%) and “no” speaking discomfort (88.7%). SRH was most commonly rated as “poor” (72.2%) (Table 1).
2. GAD by Subject Characteristics
GAD showed statistically significant differences by subject characteristics, including sex (p=.034), smoking (p=.042), alcohol consumption (p=.003), sleep duration (p=.005), chewing discomfort (p<.001), speaking discomfort (p<.001), and SRH (p=.016). Women had a higher prevalence of GAD compared with men. Current non-smokers and those who consumed alcohol also had a higher prevalence of GAD. Further, GAD was more prevalent among groups with insufficient or excessive sleep duration, those experiencing chewing discomfort, and those experiencing speaking discomfort. GAD was also more prevalent among those with poor SRH (Table 2).
3. Factors Influencing GAD
Logistic regression analysis was performed to identify the factors influencing GAD. Univariate analysis revealed statistically significant differences in sex (p<.001), alcohol consumption (p=.004), sleep duration (p=.006), chewing discomfort (p<.001), speaking discomfort (p<.001), and SRH (p=.020). The group reporting chewing discomfort had a 3.54 times higher prevalence of GAD than the group without such discomfort, while the group reporting speaking discomfort had a 3.06 times higher prevalence of GAD than the group without such discomfort. In groups reporting poor SRH, the prevalence of GAD was 2.88 times higher. Individuals who consume alcohol had a 2.53 times higher prevalence of GAD than those who do not drink. Additionally, those with insufficient or excessive sleep duration had a 2.33 times higher prevalence of GAD than those with adequate sleep duration. Compared with men, women had a 1.80 times higher prevalence of GAD.
A multivariate analysis was conducted to identify factors associated with GAD while considering the interactions between the variables. This analysis yielded statistically significant results for sleep duration (p=.031) and chewing discomfort (p=.008). Individuals with insufficient or excessive sleep duration had a 2.07 times higher prevalence of GAD than those with adequate sleep duration, while those reporting chewing discomfort had a 2.49 times higher prevalence of GAD (Table 3).
Associated Factors of Generalized Anxiety Disorder
DISCUSSION
This study was conducted using KNHANES IX-1 (2022) data to determine the factors influencing GAD among Korean older adults. The results indicate that sex, smoking, alcohol consumption, sleep duration, speaking discomfort, chewing discomfort, and SRH are associated with GAD, with sleep and chewing discomfort identified as factors influencing GAD.
In this study, 66 out of 1,613 subjects were classified as having GAD, accounting for 3.9% of the sample. The prevalence of GAD was higher among those aged 75 and older than among those aged 65~74. A study of 379 female older adults living alone based on KNHANES VIII-3 (2021) data [16] found that 7.5% had GAD, while the Seoul survey on older adults [17], using the same instrument in 2024, reported that 6.4% had GAD. It is important to note that the prevalence of GAD is gradually rising. According to a report by the Health Insurance Review and Assessment Service [18]., the number of patients with anxiety disorders, including GAD, among individuals aged 60 and older increased by 31.7% for those in their 60s, by 13.6% for those in their 70s, and by 35% for those aged 80 and older in 2021 compared with 2017. In addition, Kim and Lee [3] reported that the association between stress and GAD manifested with greater intensity in the middle-old (76~84 years) than in the young-old (65~74 years). This phenomenon can be attributed to the decline in physical function and health issues associated with aging, which often leads to reduced independence. Concurrently, changes in social roles, the loss of spouses and peers, and anxiety about death can result in a diminution of social support networks. These factors contribute to a heightened risk of mental health concerns [3,8]. The findings indicate the need for a systematic, preventive approach to mental health in older adulthood, suggesting that a multifaceted strategy is imperative. This strategy should encompass stress management programs, health promotion activities, and the activation of social support networks for older adults. South Korea became a super-aged society [19] in December 2024. As such, it has an ongoing need to prioritize the physical and mental health and well-being of its older adult population amidst the accelerating aging process, necessitating the formulation of policy directives that address the social, cultural, and national dimensions of these issues. The issue of population aging has evolved from a personal concern to a collective challenge necessitating systematic and sustained efforts from various stakeholders, including families, the government, and the broader community.
This study found sex, smoking, alcohol consumption, sleep duration, speaking discomfort, chewing discomfort, and SRH to be associated with GAD among older adults. In other words, older women, individuals who non-smoke, those who consume alcohol, those with insufficient or excessive sleep duration, those experiencing chewing and speaking discomfort, and those with poor SRH are at higher risk for GAD. The 2024 Seoul survey on older adults [17] also found that women exhibited a higher prevalence of GAD compared with men, and the National Mental Health Survey [20] reported that women had a 2.9 times higher prevalence, supporting the findings of this study. Mental health concerns, encompassing mental illness, have been demonstrated to be associated with detrimental health practices, including alcohol consumption and smoking [21]. Rather than alcohol consumption or smoking being the cause of anxiety, it is anxiety that perpetuates these behaviors [22]. Studies have suggested that smoking may increase the likelihood of anxiety disorders and that quitting smoking can reduce anxiety [22,23]. However, this study also found that non-smokers had a higher prevalence of GAD, which contrasts with previous studies. This result warrants further investigation, and future research should explore the potential connections and underlying factors behind this finding. Further, a previous study has demonstrated that individuals with poorer subjective mental health status exhibit a heightened propensity for elevated anxiety levels [17], a finding that aligns with the results of this study. In other words, older adults with higher levels of social participation tend to perceive their subjective health status more positively and exhibit greater satisfaction with their health [24]. This implies that standards and policy-level response strategies are needed to promote social participation among older adults. It is essential to augment existing initiatives that facilitate collaboration between local public health centers and senior welfare facilities, with the objective of enhancing the health behaviors of the older adult population.
In this study, the factors contributing to GAD were sleep duration and chewing discomfort. Insomnia has been observed in 44% of anxiety disorder cases [25]. Moreover, depression and GAD have been identified as contributing factors to sleep disorders experienced by older adults [26]. The Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition, Text Revision (DSM-5-TR) diagnostic criteria for GAD encompass a range of anxiety-related symptoms, including insomnia [4]. Sleep deprivation among older adults is associated with loneliness and social support [27], which ultimately affects emotional well-being, physical activity, and quality of life. Therefore, it is imperative to provide medication for GAD, in conjunction with enhancing interpersonal functioning through psychotherapy and involving family members in all treatment plans. In light of the constraints encountered by older adults when independently enhancing their sleep hygiene, the provision of education and interventions through community systems, such as public health centers and senior welfare facilities, is of paramount importance.
Further, this study identified chewing discomfort as a contributing factor to GAD, a finding that is further substantiated by prior research demonstrating a positive correlation between higher chewing discomfort scores and higher GAD scores [7]. Additionally, a higher prevalence of GAD was observed among individuals who used dentures. This observation is corroborated by findings from several studies that reported an association between diminished oral health–related satisfaction and the presence of chewing discomfort [10]. GAD has a negative impact on individuals as it reduces oral saliva secretion and increases the secretion of stress hormones [28]. Chewing discomfort has been associated with a number of health complications and social isolation due to communication difficulties resulting from reduced motor function caused by malnutrition and impaired pronunciation [7]. Therefore, chewing discomfort not only affects GAD but also reduces aesthetic appeal and impairs interpersonal relationships [10], underscoring the need for enhanced oral health policy to facilitate appropriate promotion and prevention approaches in the field of oral health.
Maintaining ego-integrity represents a pivotal developmental endeavor in older adulthood. Ego-integrity is defined as the psychological need to review past experiences, evaluate and accept the life one has lived as a worthwhile existence, and bring closure to it. As a multitude of factors have been identified as contributors to ego-integrity, including depression in old age, anxiety about death, and social activities [29], individuals, families, communities, and the state must collaborate to address the welfare, psychological, and social issues of older adults, thereby facilitating their adaptation in later life. Because anxiety is a significant predictor of quality of life [30], efforts to build social support and residential infrastructure are expected to help alleviate anxiety disorders. Moreover, as evidenced by the findings of this study and previous research [3,8,18], symptoms of GAD are comparatively minimal among the young-old (65~74 years). Therefore, both education and preparation tailored to each life stage for healthy aging (well-aging) are required, starting with early old age.
This study used KNHANES data, which were not collected specifically to identify factors influencing GAD among Korean older adults. Therefore, it has certain limitations in terms of fully identifying the diverse factors contributing to GAD in this population. Nevertheless, it is significant that this study has identified factors contributing to GAD among older adults, thereby providing a framework for health management policies targeting this population, including personal characteristics, sociocultural characteristics, and oral health–related factors.
CONCLUSION
This study identified factors influencing GAD among Korean older adults using KNHANES IX-1 (2022) data. Among the 1,613 subjects, 66 (3.9%) were classified as having GAD. The variables associated with GAD among older adults included sex, smoking, alcohol consumption, sleep duration, speaking discomfort, chewing discomfort, and SRH. Sleep duration and chewing discomfort emerged as factors influencing GAD. This study constitutes a secondary data analysis, and while it can identify factors related to GAD, its limitation lies in its inability to elucidate causal relationships. Given this study’s findings, a follow-up study that considers additional influencing factors not covered in this study will be required.
Notes
Authors' contribution
Study conception and design acquisition - HSC and GYK; Data collection - HSC and GYK; Analysis and interpretation - HSC and GYK; Writing–original draft & review & editing - HSC and GYK; Final approval - HSC and GYK
Conflict of interest
No existing or potential conflict of interest relevant to this article was reported.
Funding
This research was supported by Kyungdong University Research Fund, 2022.
Data availability
Please contact the corresponding author for data availability.
Acknowledgements
None.