Burnout and sleep quality in Korean middle-aged women before or after menopause: a cross-sectional study

Introduction

Menopause is defined as the permanent cessation of menstrual cycles for a year. Menopause occurs physiologically due to the lack of mature follicles in the ovaries, which reduces estrogen secretion. The mean age of menopause is between 50 and 52 years; however, it can vary from 44 to 54 years (1). Although menopause is a natural transition from the reproductive age to the aging process and cessation of fertility, it is characterized by symptoms that affect not only women’s everyday lives but also their physical and mental health (2). Typical menopausal symptoms include hot flashes, night sweats, irregular menstrual cycles, decreased physical strength, muscle or joint pain, bladder irritability, sleep disturbances, fatigue, and depressed mood. These symptoms vary considerably in incidence, frequency, intensity, and duration across individuals and various phases of the menopausal process (i.e., pre-, peri-, or postmenopausal periods) (3,4).

Sleep disturbances, such as difficulty in falling sleeping, waking up at night, difficulty in resuming sleep after waking up, and waking up earlier than usual, are among the most troublesome symptoms of menopause and are reported by almost half of menopausal women (5,6). Changes in sleep patterns that lead to sleep disturbances are associated with hormonal status during the menopausal transition. The serotonin level, which is an important factor in the sleep process, is reduced along with a decline in estrogen and progesterone during menopause. Reduced serotonin levels are associated with sleep disorders (7) although aging is also related to sleep disorders (8,9). Sleep has always been considered an essential human need, and both sleep quantity and quality are essential for optimizing all body systems (7,10). Good sleep quality refreshes the mental, psychological, and physical condition of an individual, whereas poor sleep quality is negatively associated with normal cognitive function, emotional balance, and overall wellbeing (11,12).

Some of the most common menopausal symptoms are mental and physical exhaustion, particularly emotional exhaustion (13,14). This study focuses on burnout, which may be a component of menopausal symptoms. Bourgault mentioned that few studies have noted that burnout symptoms, such as depersonalization and emotional exhaustion, among middle-aged women before or after menopause may resemble signs of estrogen deficiency (15). Burnout occurs when individuals feel overly emotionally and physically drained (16). Burnout symptoms typically include fatigue, mood changes, forgetfulness, trouble concentrating, apathy, feelings of detachment in relationships, and indecision (17). The emotional and psychological symptoms associated with menopause are almost identical to those of burnout (15,17). In qualitative studies investigating the menopausal experiences, aging, and life experiences of Korean middle-aged women, psychological phenomena associated with feelings of loss, emptiness, helplessness, worthlessness, despair, loneliness, low self-esteem, and depression were commonly reported (18). These psychological phenomena in menopausal middle-aged women can accelerate their burnout.

When middle-aged women before or after menopause experience frequent burnout symptoms along with sleep disturbances, poor sleep quality and burnout should be addressed as common health problems. Little research has been done on poor sleep quality and burnout in middle-aged women before or after menopause. This study aimed to examine the association between sleep quality and burnout in middle-aged women before or after menopause. This article is presented in accordance with the STROBE reporting checklist (available at https://jhmhp.amegroups.com/article/view/10.21037/jhmhp-24-108/rc).

Methods

Study design

This was a cross-sectional, descriptive correlational study that analyzed survey data collected using a self-administered questionnaire. The study was conducted in accordance with the Declaration of Helsinki and its subsequent amendments. The study was approved by Chonnam National University (No. 1040198-230712-HR-091-02) and informed consent was obtained from all individual participants.

Participants

Subjects eligible for this study were middle-aged women before or after menopause. The inclusion criteria were as follows: (I) middle-aged women aged between 44 and 55 years and (II) middle-aged women who understood the purpose of the study and voluntarily agreed to participate in an online survey. Considering that Korean women experience menopause at approximately 48 to 52 years (19), the age of the study participants was limited to 44 to 55 years. This age group encompasses the menopausal age range of Korean women and is more likely to include individuals experiencing menopausal symptoms than other middle-aged age groups (9). The exclusion criteria were middle-aged women who could not read and answer questions in Korean.

Participants were recruited in August 2023 using an online survey panel developed by a survey company (SurveyBilly, Seoul, South Korea). An online survey can be easily accessed from anywhere with an internet connection, increasing the likelihood of survey participation, and reduce the possibility of errors in the data collection process because survey responses are automatically collected and organized (20,21). The author provided the company with a recruitment letter for participation in the study. This letter included the title and purpose of the study, the inclusion and exclusion criteria, the benefits and risks of participating in the online survey, the time required to complete the survey, and information regarding subject anonymity, voluntary participation, and informed consent. For the recruitment process, the survey company had a panel database of over 20,000 people segmented by gender, age, job, and position. Individual panel members who met the inclusion criteria for this study were invited to participate in the online survey via smartphone text messages containing the recruitment letter and a survey link. Reminders were sent twice at two-week intervals. Women were recruited from each menopausal stage, including the premenopausal, perimenopausal, and early postmenopausal stages, which accounted for approximately one-third of the total sample size. When the participants responded to the distributed survey, their responses were automatically collected in a data format in an Excel sheet. The final dataset compiled by the survey company was emailed to the author as an Excel file (Microsoft Excel, Redmond, WA, USA). The F test in G*Power 3.1.9.2 software indicated a minimum sample size of 180 based on a significance level (α) of 0.05, an effect size of 0.25, and a statistical power of 0.85 (22). Overall, 214 middle-aged women were recruited, considering an expected dropout rate of 10%. Fourteen persons were excluded because the questionnaires were not completed. Therefore, 200 participants were included in this study.

Measures

Participant characteristics

Questions about participant characteristics were divided into demographic factors and menopause-related factors by referring to Korean studies targeting middle-aged and menopausal women (23,24) (Appendices 1-3). The demographic factors consisted of nine items: age group, educational level, marital status, family type, job, average monthly income, alcohol consumption, exercise, and present health status. To avoid inappropriately dividing the menopausal age range of Korean women, age groups were divided into three-year intervals. The specific classifications of the other demographic characteristics were determined in reference to previous studies (23,24). Menopause-related factors consisted of three items: menopausal status, menopausal symptoms, and use of female hormones. For menopausal status, the participants were asked to choose one of the following three options: premenopause with menstruation, perimenopause with amenorrhea for less than one year since the last menstrual period, and postmenopause with amenorrhea for more than one year since the last menstrual period. For menopausal symptoms, the participants were asked to choose one of the following four options based on the severity of their symptoms: no, mild, moderate, and severe symptoms.

Burnout

The Korean version of the Personal Burnout Instrument from the Copenhagen Burnout Inventory was used to measure burnout (25,26). Personal burnout refers to the degree of physical and psychological fatigue and exhaustion experienced by an individual (25). The Personal Burnout Instrument consists of six items rated on a 5-point Likert scale (1 = never, 2 = seldom, 3 = sometimes, 4 = often, and 5 = always), with higher scores indicating higher levels of burnout. In this study, Cronbach’s alpha was 0.93 compared to 0.95 in a study by Kang (26), and it ranged from 0.85 to 0.87 during the instrument’s development (25).

Sleep quality

Four items selected from the Brief version of the Pittsburgh Sleep Quality Index were used to measure sleep quality (27). The Korean version of the Pittsburgh Sleep Quality Index was used for the four items translated into Korean (28). The four items were as follows: “How long does it usually take you to fall asleep each night over the last month?”, “How many hours of actual sleep did you get at night over the last month?”, “Have you had trouble sleeping because you wake up in the middle of the night or early in the morning over the last month?”, and “How would you rate your sleep quality overall over the last month?”. The four-item instrument was rated on a 4-point Likert scale, with higher scores indicating higher levels of sleep quality. In this study, Cronbach’s alpha was 0.80, and it ranged from 0.79 to 0.84 in previous studies (27,28).

Statistical analysis

This study used SPSS WIN 27.0 (IBM Corp., Armonk, NY, USA) for data analysis. The personal characteristics of the participants were analyzed using frequencies and percentages. Burnout and sleep quality variables were analyzed using overall means and standard deviations (SDs). The Kolmogorov-Smirnov test showed that the data were normally distributed (P=0.498) (29).

Independent samples t-tests and one-way analysis of variance (ANOVA) were used to determine whether there were significant differences in the means of burnout and sleep quality according to personal characteristics. For post-hoc tests, the Scheffe test or Games-Howell test was used, depending on whether equal variances were assumed. Pearson’s correlation coefficient was used to determine the relationship between burnout and sleep quality. Multiple regression analysis using dummy variables was performed to identify factors related to burnout. Demographic and menopause-related variables that showed significant differences in burnout through independent samples t-tests and one-way ANOVA were converted to dummy variables, and the dummy variables were included as independent variables in the multiple regression analysis to control for exogenous and confounding variables. The Durbin-Watson test was performed to identify residual independence. Tolerances and variance inflation factors (VIFs) were used to check for multicollinearity between the independent variables. The reliability of the instruments was examined using Cronbach’s alpha coefficient. The level of statistical significance was defined as a P value less than 0.05.

Results

Characteristics of middle-aged women

Table 1 shows the personal characteristics of the 200 middle-aged women who completed the online survey. In terms of these baseline characteristics, 85.5% were between 47 and 52 years of age, 68% had a college degree or higher, 85% were married, 84% were in couple-centered nuclear families, 62% were employed, 41% had a monthly income of more than 3 million Korean Won (KRW) (i.e., approximately over 2,500 USD), 64.5% did not drink alcohol, 59.5% exercised, and 85.5% perceived themselves to be healthy. In terms of menopause-related characteristics, 68.5% were menopausal, 61.5% had mild (39.5%), moderate (18%), and severe (4%) menopausal symptoms, and 94% did not take female hormonal medicine.

Burnout and sleep quality according to personal characteristics

Table 2 shows that the overall means for burnout and sleep quality were 2.65 (SD =0.93) and 2.85 (SD =0.66), respectively. Table 1 shows that burnout and sleep quality exhibited statistically significant differences (all P<0.001) based on job status, average monthly income, present health status, menopausal status (P=0.003 for burnout), and menopausal symptoms. Burnout also showed statistically significant differences according to age group (P<0.001), family type (P=0.04), and alcohol consumption (P=0.02). Sleep quality showed a statistically significant difference based on educational level (P=0.01). Table 1 also presents the post-hoc test results for age group, family type, average monthly income, menopausal status, and menopausal symptoms that showed significant differences in one-way ANOVA. For example, burnout was significantly higher in the 47–49 age group than in the 50–52 age group. Burnout was also significantly higher in middle-aged women with moderate and severe menopausal symptoms than in those without menopausal symptoms. Sleep quality was significantly higher in middle-aged women without menopausal symptoms than in those with mild, moderate, and severe menopausal symptoms. Table 3 shows that burnout was negatively associated with sleep quality (r=−0.489, P<0.001).

Burnout-related factors

Table 4 shows the results of the multiple regression analysis using dummy variables. The regression model predicting burnout was significant (F=11.324, P<0.001), and the coefficient of determination (adjusted R²) for explaining the model was 0.454. The Durbin-Watson value was 1.924, indicating that the condition of residual independence was met. The tolerances were above 0.1, and the VIFs were less than 10, indicating no multicollinearity issues among the independent variables, including the dummy variables. Better sleep quality (β=−0.260, P<0.001), no alcohol consumption (β=−0.118, P=0.04), the absence of menopausal symptoms (β=−0.442, P=0.004), and mild menopausal symptoms (β=−0.314, P=0.03) were significantly associated with reduced burnout. Average monthly incomes between two and three million KRW (β=0.181, P=0.005) and the perception of oneself as unhealthy (β=0.180, P=0.004) were significantly associated with increased burnout. The major factors predicting burnout were the absence of menopausal symptoms (β=−0.442), mild menopausal symptoms (β=−0.314), and sleep quality (β=−0.260).

Discussion

In middle-aged women before or after menopause, the mean score for burnout was 2.65 points, and the mean score for sleep quality was 2.85 points. These mean scores on a 5-point scale do not seem to indicate that overall, the study participants experienced poor sleep quality or severe burnout. With regard to sleep disturbances, a review study by Santoro et al. (9) reported that the pattern of sleep disturbances appears in the early menopausal transition, peaks in the late transition, and remains generally unchanged through postmenopause. According to the Stages of Reproductive Aging Workshop+10 (STRAW+10) criteria, the timing of the onset of early menopausal transition is variable, and the late menopausal transition occurs one to three years before menopause (30). The results of this study were somewhat different. The perimenopausal participants (less than a year since their last menstrual period, mean =2.51) in the early menopausal transition had significantly lower sleep quality than the postmenopausal participants (more than a year since their last menstrual period, mean =3.07) in the late menopausal transition.

The results of this study showed that better sleep quality was associated with lower burnout. Several studies involving nurses and physicians reported a correlation between low sleep quality including dissatisfied sleep, sleep disturbances, and insomnia, and increased burnout including emotional exhaustion, low self-compassion, depersonalization, and cynicism (16,31-33). These previous studies targeted healthcare professionals that were currently working. In a study by Chen et al. (16), poor sleep quality and burnout were positively correlated even after adjusting for job status, which is a confounding variable.

This study showed that having no or mild menopausal symptoms was significantly associated with reduced burnout. The mean analysis of burnout according to menopausal symptoms showed that burnout increased continuously in proportion to the severity of symptoms. In particular, the participants with moderate (mean =3.10) and severe (mean =3.41) menopausal symptoms reported significantly higher burnout than the participants without menopausal symptoms (mean =2.33). A previous study of Dutch working women also found increased emotional exhaustion in working women with menopausal symptoms, most notably in perimenopausal women who frequently experienced menopausal symptoms (14). In this study, the employed participants reported significantly increased burnout compared with the unemployed participants. However, employment status was not a significant factor associated with increased burnout (β=0.086, P=0.19).

Regarding menopausal status, the mean analysis of burnout according to menopausal status showed that the premenopausal participants (mean =2.85) and the perimenopausal participants (mean =2.80) reported significantly higher burnout than the postmenopausal participants (mean =2.37). However, menopausal status was not a significant factor associated with increased or decreased burnout (for premenopause, β=0.129, P=0.09 and for perimenopause, β = 0.029, P=0.66). This may indicate that the severity of menopausal symptoms is more strongly associated with burnout than menopausal status.

Regarding average monthly incomes, having a monthly income between two and three million KRW was significantly associated with increased burnout compared with the other monthly incomes. Women before or after menopause may have relatively many financial responsibilities due to being the parents of adolescents, paying for their children’s tuition, and taking care of their elderly parents (34). These financial responsibilities might be related to increased burnout. To gain more insight, qualitative research is needed to explore why middle-aged women with monthly incomes in this range experience increased burnout. Regarding self-reported present health status, the results of this study showed that perceiving oneself to be unhealthy was significantly associated with increased burnout. Perceiving oneself to be unhealthy may be different from the presence or absence of actual health problems. To properly understand the association between the perception of health status and burnout in middle-aged women before or after menopause, it is necessary to investigate whether these middle-aged women have actual acute or chronic diseases, how these diseases are managed, whether they affect all aspects of daily life, and in particular whether they are associated with increased burnout. Abstaining from alcohol consumption was significantly associated with reduced burnout in the middle-aged women in this study. Similarly, psychological factors such as depression, anxiety, stress, fatigue, sleep disturbances, and changes in cognitive function and processing speed during the menopausal transition can trigger alcohol misuse (35). A scoping review study indicated that alcohol consumption among women increases after menopause and that women are more vulnerable to alcohol-related harms than men. This is because women have less alcohol-decomposing enzymes than men and their body composition consists of more fat than water, causing the concentration of ethanol to rise quickly in the blood (35).

This study has some limitations. First, collecting a convenience sample online through a panel database from the survey company may have introduced bias in the recruited sample, affecting the results. Second, the use of a self-report method with an online survey may have resulted in response bias, where responses vary depending on the subjective tendencies of the respondents. Therefore, caution is needed when applying the results of this study to other middle-aged women. Finally, based on the literature, other confounding variables, such as occupation type, years of employment, and working hours (14,16), physical activity (7,36), chronic physical illness (37), and reproductive history (37) were not investigated. This might be another limitation.

Conclusions

This study may be the first to consider burnout as a component of menopausal symptoms. Better sleep quality and the absence of menopausal symptoms were strongly associated with decreased burnout. These associations involving burnout are the highlight of this study. Based on these findings, specific information on experiences of burnout and sleep quality related to menopause should be explored, and psychological and physical programs to help middle-aged women who experience sleep disturbances and burnout symptoms are needed.

Acknowledgments

None.

Footnote

Reporting Checklist: The author has completed the STROBE reporting checklist. Available at https://jhmhp.amegroups.org/article/view/10.21037/jhmhp-24-108/rc

Data Sharing Statement: Available at https://jhmhp.amegroups.com/article/view/10.21037/jhmhp-24-108/dss

Peer Review File: Available at https://jhmhp.amegroups.com/article/view/10.21037/jhmhp-24-108/prf

Funding: This study was financially supported by Chonnam National University (Grant number: 2023-1115-01).

Conflicts of Interest: The author has completed the ICMJE uniform disclosure form (available at https://jhmhp.amegroups.com/article/view/10.21037/jhmhp-24-108/coif). The author has no conflicts of interest to declare.

Ethical Statement: The author is accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved. The study was conducted in accordance with the Declaration of Helsinki and its subsequent amendments. The study was approved by Chonnam National University (No. 1040198-230712-HR-091-02) and informed consent was obtained from all individual participants.

Open Access Statement: This is an Open Access article distributed in accordance with the Creative Commons Attribution-NonCommercial-NoDerivs 4.0 International License (CC BY-NC-ND 4.0), which permits the non-commercial replication and distribution of the article with the strict proviso that no changes or edits are made and the original work is properly cited (including links to both the formal publication through the relevant DOI and the license). See: https://creativecommons.org/licenses/by-nc-nd/4.0/.

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