Risk factors of mental disorders among empty and non-empty nesters in Shanxi, China: a cross-sectional study

China has a rapidly aging population. According to the annual data of the National Bureau of Statistics of China (CNBS), 230 million people aged 60 years and above accounted for 16.7% of the total population in 2016, an increase of 15.6% from 199 million in 2010 [1, 2]. Moreover, traditional living arrangement has been challenged by the disintegration of the extended family in recent years. With the decline in the number of adult children available to help the needing elders, the proportion of elders living alone or living with their spouse is increasing. These elders are called the “empty nesters” [3]. The estimated number of empty nester households will account for 90% of the elderly households by 2030 [4].

As substantial demographic change happens, mental disorders (e.g., depression, anxiety, impulse control, and substance abuse) in the elders become a type of major health challenge [5, 6]. Among the consequences of mental disorders are loneliness, increased risk for physical illnesses (e.g., ischemic heart disease, stroke, cancer), cognitive decline, impairments in activities of daily living. And depression, a widespread type of mental disorders, causes a common disability in the elders and decreases in life satisfaction [5]. In addition, the incidence of dementia has increased at an alarming rate worldwide, especially in China where over nine million elders suffer from dementia, constituting 3.2 to 9.9 percentage of the Chinese elders [6]. In addition, Mental disorders play a prime role for suicide attempt in rural China [7] and almost all the elderly suicide victims are preceded by mental disorders [8]. Taking care of elders with mental disorders brings considerable physical, mental and financial spending to their families, and needs substantial of medical resources and healthcare support from government assistance, the community and institution care [6]. Hence, the primary prevention of mental disorders and promotion of mental health of the elderly are of utmost importance [9], and an evaluation of mental disorders and its risk factors among elders is urgently needed.

Previous studies showed that empty nesters without a traditional family providing for them were in a dire condition regarding life satisfaction [10], quality of life [11], health-promoting lifestyle [4] and social support [12]. Does the empty-nest living arrangement contribute to the mental disorders of elders? There have been some researches to report the mental disorders of elders or empty nesters. Yu [13] indicated that over 39% of elders reported depressive symptoms, which were related with the lack of social support and poor physical health. A researcher declared that the Geriatrics Depression Scale score, which was adopted to assessed the level of depression, was significantly higher in rural empty nesters. A cross-sectional study from Sichuan province showed that anxiety disorders prevailed in empty nesters [14]. The associations with mental disorders were found in all aspects of gender, relationship with their children, monthly income, chronic diseases and self-care ability [15‐17]. However, studies focusing on the disparity of mental disorders and its related factors among empty and non-empty nesters were relatively less. Several researches indicated that empty nesters had higher levels regarding depressive symptoms and loneliness feelings compared with non-empty ones [18‐20], while our pilot study (n = 488) conducted in Taiyuan, capital of Shanxi Province, China, suggested that non-empty nesters had poorer mental health status compared with empty ones, such as in somatization, obsessive-compulsiveness and psychoticism [21]. Based above, we expanded the research areas and increased the number of people surveyed to explore which elderly group was more susceptible to mental disorders. In addition, the pilot study used Symptom Check-list 90 (SCL-90), an international self-assessment questionnaire of psychological problems and symptom distress, as the survey tool [21, 22]. But in the process of actual investigation, we found that the compliance and acceptance of the elders was poor due to the more entries of SCL-90. In this study, we adopted Chinese Health Questionnaire (CHQ-12) as the research tool for measuring mental disorders, which has been suggested as effective as and more efficient than the longer version [23, 24], and also seems to be more suitable for elders than the longer version due to its simplicity. The purpose of this study was to comparatively evaluate the mental disorders among empty and non-empty nesters, and explore the risk factors among empty and non-empty nesters, thus providing effective theoretical basis for interventions and prevention of the mental disorders among empty and non-empty nesters.

The observed rate of mental disorders was higher in empty nesters (26.9%) compared with non-empty ones (23.5%), indicating that the former were more vulnerable to mental disorders than the latter. Moreover, the final result also supported the related comparative studies [18‐20], which indicated that empty nesters had higher levels regarding specific psychiatric problem and symptom distress. However, the conclusive point was inconsistent with the findings in our pilot study [21]. Different living areas may account for the varied outcome. 65% of the participants in this study resided in rural areas, while 66.0% of the study subjects lived in urban areas in our pilot study. Many previous studies have indicated that empty nesters living in the rural had significantly more serious mental distress compared with those who lived in the city [14, 29]. In rural China, the traditional concept of ‘bring up their children for old age’ of elders is relatively strong. The elders are accustomed to relying on their children, while leaving away from their children (an empty-nest status) easily make them into a boring and hopeless life. Whereas for empty nesters living in the urban areas, their independent economic ability and open mind, as well as free time enable them to enjoy interactive activities and light mood. In addition, different measurement tools may also be responsible for the discrepancy. SCL-90 contains nine dimensions and focuses on nine aspects of mental health: somatization, obsessive-compulsive, interpersonal sensitivity, depression, anxiety, hostility, phobic anxiety, paranoid ideation and psychoticism [22], while CHQ-12 only pays attention to mental disorders in a unidimensional perspective.

After further analysis, a significant association between empty nesters who lived alone or lived in an institution and mental disorders was found. A previous study pointed that pension agency may block the social relationship network of the community where the elders were located, making elders lack necessary interactions and communications, thereby causing poorer mental health [30]. However, empty nesters living with spouse didn’t have higher mental disorders in comparison to non-empty ones. The finding reflected that the spouse had a salutary effect on empty nesters’ mental health, which was consistent with the study result of Cheng [20]. After children departed from home, their spouse may be the most understanding and closest person to them and serve as the strong pillar to provide them emotional support against loneliness or other bad emotion [31]. Our study results pointed that empty nesters overall, especially the ones who lived alone or lived in an institution, had a higher prevalence of mental disorders than non-empty nesters.

The common risk factors related to mental disorders in the two groups were in the lack of self-care ability and having chronic disease. Lower monthly income, paying no or less attention to healthy diet and single status were uniquely associated with higher mental disorders in empty nesters. And middle age(70~79 years) was a protective factor of mental disorders for non-empty nesters relative to high age (80 years or above). Moreover, chronic diseases and monthly income, which had been found and fully explained in our pilot study [21], were confirmed again in this study.

The lack of self-care ability was a risk factor contributing to mental disorders in both groups. There is a strong link between physical and mental health [32]. A mediation analysis demonstrated that physical activity is the pathway through which physical health influences mental health [33]. Community health service centers should establish various forms of fitness equipment to attract the elderly to exercise; carry out community health education and psychological counseling to elevate elders’ awareness of self-care; and improve disease rehabilitation services by strengthening specialized training of family caregivers to improve the status of hardly or part self-care ability, and to promote rehabilitation of patients’ psychological, physical, and social functions.

Being single was a risk factor in the mental disorders among empty nesters, which proved the importance of spouse who could be responsible for companionship and emotional comfort. Whereas for the non-empty nesters, the companionship of the children made up for the lack of spousal companionship, which made the impact of being single on their mental health less prominent. Therefore, married elders, especially empty nesters, should be encouraged to cherish the time spent with their old partners. And the single empty nesters should socialize with others in diverse team activities and believe a late-life love is not all they need for a good life. Simultaneously, the community-based primary prevention for mental disorders should be strengthened to promote mental health of the empty nesters, especially for single ones. In addition, adult children should increase the amount of time they spend with their parents and visit their aging parents more frequently.

In this study, the empty nesters who never attended to daily healthy diet (3.78 ± 2.20) or paid less attention (3.29 ± 1.88) had higher CHQ-12 scores than those paying more attention (2.90 ± 1.59) or most attention (2.79 ± 1.54). And never paying attention to healthy diet (OR = 2.04; 95% CI = 1.41, 2.97) or paying less attention (OR = 1.58; 95% CI = 1.29, 1.94) was significantly associated with mental disorders in empty nesters, but it was not the influencing factor for the non-empty nesters. There is a growing priority internationally about that dietary risk factor, as well as physical health, has a close relationship with increased prevalence of mental disorders [34, 35]. Previous studies presented various evidences, indicating that key nutrients or diet components, such as antioxidants, omega-3 fatty acids, and B vitamins, from a healthy whole food diet played a pivotal role in cognitive function and mental disorders [35‐37]. Whereas contextual factor (social, physical, and environmental) affected dietary intake and quality [37]. In this study, contextual factors of the two subjects: empty and non-empty nesters, were different, such as family support and dietary pattern. In China, non-empty nesters living with their children have two conditions with respect to diet. One is that their children intimately arrange daily routines and reasonable diet for them; the other is that they have to prepare regular and balanced diet for their children who go to school or work. Hence, whether or not they actively focus on healthy diet, their diet is always in regular shape. This phenomenon is called “compulsive healthy diet”. So that the effect of whether or not paying attention to daily diet on mental disorders in non-empty nesters is insignificant. In contrast, empty nesters living independently have no children’s care and do not need to take care of their children. Hence, their diet depends completely on whether or not they pay attention. The community service centers should hire dietitians and food hygiene supervisors for carrying out diet health education to the elderly, in reference to the Chinese Dietary Guidelines (2016) [38]. This is especially important for empty nesters who should be instructed individually and consistently to enhance their balanced diet awareness. Health management centers should consider bringing meals-on-wheels service to empty nesters.

In addition, lower income had a positive association with mental disorders for empty nesters, which was consistent with Wang’s findings [39]. Higher income is significantly associated with lower psychological pressure, which is responsible for the marked improvement in mental health status. In rural China, the coverage of social security funds is lower than in the cities, the elder’s economic source of life is mainly from farming or family support. While non-empty nesters could depend on their children, empty nesters’ incomes are the most direct dependence for the security of life. The government should expand the coverage of welfare (especially the pension plan) [40] and give commercial pension insurance active guidance to exert its complementary role on social security of elders. Moreover, individuals should strengthen personal awareness of commercial pension insurance investment for future security. In addition, filial piety as a basic Chinese principle should be advocated; no matter where the children go to, it is incumbent for the elders.

We acknowledge the study had several limitations. First, the sample population were selected from Shanxi Province, thus these results may not be representative of the elders in other areas in China with different economic and geographical features. Second, the data collection, which was based on questionnaires and had no objective measurement, was subjective. Third, this was a cross-sectional study; therefore, the results failed to prove a causal relationship between risk factors and mental disorders.

This study indicated that empty nesters, especially the ones living alone and living in an institution, were more vulnerable to mental disorders than non-empty ones. And the elderly, who could completely care themselves and did not have chronic diseases, had lower prevalence of mental disorders. While having a higher income, married status and paying more attention to daily healthy diet uniquely contributed to empty nesters’ mental disorders. The results suggested scientific evidence for targeting interventions addressing risk factors of mental disorders among elders. Moreover, it contributed to the primary prevention of mental disorders and improvement of quality of life, as well as the formulation of health management strategies for elders.