Article Text
Abstract
Objectives This study identifies depressive symptoms and the factors that could explain its presence in breastfeeding people.
Design This study is a cross-sectional study from national survey data.
Setting and participants Data were derived from the 2019 Korean Community Health Survey. The study subjects were breastfeeding people under the age of 50.
Primary outcome measures Depressive symptoms in breastfeeding people were classified according to the Patient Health Questionnaire-9 (PHQ-9) score. Physical and health behaviours were considered as factors related to depressive symptoms. A multilevel logistic regression analysis was used.
Results Among 497 participants, 19.4% (n=97) of breastfeeding people were depressed. We found that depressive symptoms were associated with age (31–35, OR: 0.79, 95% CI: 0.67 to 0.94; 35–49, OR: 0.42, 95% CI: 0.32 to 0.56), rural setting (OR: 0.62, 95% CI: 0.51 to 0.76), economic activity (OR: 0.75, 95% CI: 0.61 to 0.91) and physical health (diabetus mellitus or hypertension, OR: 5.17, 95% CI: 3.78 to 7.06).
Conclusions This study implies that socioeconomic factors, physical health and health behaviours may influence depressive symptoms in breastfeeding people. These findings should be used as descriptive data to support the development of education programmes to help breastfeeding people.
- public health
- depression & mood disorders
- primary care
Data availability statement
Data are available in a public, open access repository.
This is an open access article distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited, appropriate credit is given, any changes made indicated, and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/.
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STRENGTHS AND LIMITATIONS OF THIS STUDY
This study is significant because it investigated depressive symptoms and its influencing factors in breastfeeding people using Korea’s representative community health survey data.
This study investigated depressive symptoms in breastfeeding people using the Patient Health Questionnaire-9. This is meaningful because this enables a comparison of depressive symptoms with other community population groups.
It used a cross-sectional design with secondary data; therefore, it is difficult to explain the temporal context of depressive symptoms in breastfeeding people and their related factors.
Introduction
Mental health has emerged as a national problem in Korea due to rapid economic growth and changes in social values.1 2 Depression is a disease that causes a decrease in daily functioning by causing various cognitive, mental and physical symptoms with a decrease in motivation as the main symptoms, and it is more common than other mental diseases.3 4 According to the WHO, 5% of adults and 280 million people worldwide suffer from depression.5 Depression shows an increasing trend in both developing and developed countries regardless of income level.6 The proportion of Korean adults who experienced depression was 11.2%.7
Depression does not appear once; its prevalence varies according to life events.2 8 Women experience depression twice as often as men.9–11 It is caused by a complex interaction of physiological and social factors.8 The risk of a first occurrence of depression in women increases significantly during pregnancy and with childbearing-related hormonal changes.12 Depression after childbirth is an important mental health issue because it is highly likely to develop into chronic depression following this period.3 13
After childbirth, women become physically and psychologically tired from new responsibilities beyond their capabilities. In severe cases, women can feel helpless, guilty and depressed.14 Breast feeding is associated with depression in reproductive women; however, no clear relationship between maternal depression and breast feeding has been confirmed.15 Breast feeding mothers have increased parasympathetic nervous system regulation, and reduced stress and depressive symptoms when compared with formula-fed mothers.14 By contrast, depression in women is associated with the initiation or discontinuation of breast feeding.15 16 Depressive mothers have less interaction with newborns and reduced touching, sensitivity and skin to skin contact. Consequently, newborn weights do not increase at the normal rate due to poor suckling and decreased milk intake.17
The factors influencing depression in breastfeeding people include hormonal changes after childbirth, changes in maternal roles and demographic and health-related factors. The demographic factors are living alone, low education levels and low income.10 18 19 In addition, women are more likely to experience depression when they are less physically active, drink or smoke or are under a lot of stress.9 18 19 The physical health factors include women with chronic diseases, such as diabetes, ischaemic heart disease, and stroke.9 18 20
Previous studies on breastfeeding people have mainly focused on the factors affecting breastfeeding practices17 21 or the effects of breast feeding on women’s health.22–24 Few studies have assessed the impact of demographic and health characteristics on depression in breastfeeding people. Breast feeding is essential for the growth and development of babies; therefore, as a topic of national health policy,5 it is necessary to understand the depression of these women.
Depressive symptoms can be a fatal psychopathology for individuals. Additionally, depression in mothers of young children has a profound negative effect on the development of young children.22 Therefore, early screening and active preventive interventions would be most effective. This study aimed to investigate the effects of demographic and health factors on depression in breastfeeding people using the Community Health Survey.25 Based on this, we sought to offer basic data for the development of a mental health programme for breastfeeding people.
Methods
Study population
This study uses the 2019 Korea Community Health Survey (KCHS).25 It was conducted at 255 health centres nationwide since 2008 for adults aged ≥19 years to produce comparable regional health statistics to formulate and evaluate regional healthcare plans. Briefly, a trained investigator visits each household selected as a sample, describes the survey and confidentiality, receives consent to participate and conducts a 1:1 interview method survey.
Of the 229 099 participants from the 2019 KCHS, breastfeeding people aged <50 years were included in this study. The exclusion criteria were men, women aged ≥50 years, women who were not breast feeding and missing related questionnaire replies (Patient Health Questionnaire-9 (PHQ-9) score, health behaviours and health-related questions) (figure 1). In this study, breastfeeding people were defined as woman who answered, ‘Be breastfeeding after giving birth’ to the question, ‘Are you currently menstruating?’. The final sample included 497 breast feeding people. Participants were categorised into two groups: ‘Non-depressed’ (n=400) or ‘Depressed’ (n=97), depending on their PHQ-9 score. The raw data used in this study were provided by the Korea Disease Control and Prevention Agency (KDCA), which manages healthcare resources including human resources for healthcare, health facilities and medical equipment in South Korea. These data are openly available at the Public Data Portal (https://chs.kdca.go.kr/chs/index.do).
Study variables
The demographic characteristics were age, area of residence, economic activities and level of education. Participants were stratified by age into 19–30, 31–35 and 36–49 groups, based on the mean and quartiles of breastfeeding people. The area of residence was divided into urban (~dong) or rural (~Eup, myeon). Economic activities were defined by the question ‘Did you work more than 1 hour for income purposes in the last week or have you worked as an unpaid family worker for more than 18 hours?’. The responses were divided into ‘yes’ or ‘no’. Education levels were divided into two categories: ≤high school and ≥college.
The PHQ-9 is based on the nine diagnostic criteria for major depressive disorder from the Diagnostic and Statistical Manual Fourth Edition. The scale can serve as a dual-purpose instrument to screen for the presence of depressive disorder and assess the severity of symptoms.9 11 All items share the header, ‘‘Over the last 2 weeks, how often have you been bothered by any of the following problems?’. The questions share response options ranging from 0 (‘not at all’) to 3 (‘nearly every day’). Total PHQ-9 scores range from 0 (absence of depressive symptoms) to 27 (most severe depressive symptoms). Major depression is diagnosed if five or more of the nine depressive symptoms are present. The consistency of Edinburgh Postnatal Depression Scale and PHQ-9 in measuring depression in postnatal women has been assessed. Studies26 27 report that five points can be used as a cut-off in the PHQ-9 scale to distinguish depressive symptoms in these women. Therefore, a 5 point cut-off score was used to classify depressive symptoms of breastfeeding people in this study. We defined a score below 5 points as without depressive symptoms and above 5 points as with depressive symptoms.
The physical health characteristics assessed in this study were obesity, hypertension and diabetes. Previous literature reviews9 11 20 have reported that these are modified in depression. Obesity was defined as BMI (kg/m2) ≥30; BMI <30 was considered normal.11 Hypertension and diabetes were reported based on a medical diagnosis.
The health behaviour characteristics assessed in this study were sleep duration and flexibility exercise. Previous literature reviews10 18 19 have confirmed that these are modified in depression. Sleep duration was classified based on the number of hours of sleep (0–5 hours, 6–7 hours and ≥8 hours). Flexibility exercise was classified by the number of days over the previous week that flexibility exercise, such as stretching, had been performed.
Data analysis
Data analysis was carried out using the IBM SPSS statistics V.23.0 program. Since the community health survey samples were collected under a complex sampling design, a composite sample plan file reflecting stratified variables, colonies and weights was generated according to the data analysis guidelines of the KDCA, and then a composite sample analysis was undertaken. The characteristics of demographic factors, health behaviours and physical health were described using frequency and percentage. Overall differences in proportions between groups were analysed using the χ2 test. In order to determine the effects of demographics, health behaviour and physical health on PHQ-9 in breastfeeding people, multiple logistic regression analysis was conducted. Each OR was reported together with its 95% CI. All statistical significance levels were set at p<0.05.
Patients and public involvement
Patients and/or the public were not involved in the design, conduct, reporting or dissemination plans of this research.
Results
Demographic characteristics
The demographic characteristics of the 497 breastfeeding people included in this study are shown in table 1. The proportion of participants aged 19–30 years was 28.3% (n=133), 31–35 years was 45.4% (n=228) and 36–49 years was 26.3% (n=136). The average age was 32.95±4.41 years. Most participants lived in an urban area (84.8%), with 15.2% living in a rural area. In total, 81.4% of the women were not engaged in economic activities (18.6% were engaged in economic activities). The proportions of women with no more than a high-school education and at least a college education was 15.0% and 85.0%, respectively. The proportions of women who scored 0–4, 5–9, 10–14 and ≥15 points on the PHQ-9 were 80.6%, 14.5%, 4.1% and 0.8%, respectively.
Characteristics of the subject according to PHQ-9 scores
The PHQ-9 scores revealed that 80.6% (n=400) and 19.4% (n=97) of breastfeeding people were not depressive and were in the depressed group (table 2). There was a significant difference in age, residence, economic activity, diabetes or hypertension, sleep duration and exercise between ‘Non-depressed’ and ‘Depressed’ groups (p<0.001). In terms of education, 14.8% of breastfeeding people who had graduated from high school or below were depressive and 85.2% had at least graduated from a college; however, this difference did not reach significance (p=0.780). Additionally, 94.8% of the women in the depressed group were not obese, while 95.2% were not obese in the 19–30 group (p=0.141).
Factors affecting depressive symptoms in breastfeeding people
Table 3 shows the effects of demographic characteristics, physical health and health behaviours on depressive symptoms in breastfeeding people.
The likelihood of depressive symptoms in women aged 31–35 and 36–49 years was lower (OR: 0.79, 95% CI: 0.67 to 0.94 and OR: 0.42, 95% CI: 0.32 to 0.56, respectively) when compared with breastfeeding people 19–30 years of age. Compared with breastfeeding people living in urban areas, those living in rural areas were less likely to report depressive symptoms (OR: 0.62, 95% CI: 0.51 to 0.76). Moreover, those who engaged in economic activities had a reduced chance of reporting depressive symptoms when compared with those who did not engage in economic activities (OR: 0.75-fold, 95% CI: 0.61 to 0.91). breastfeeding people who at least graduated from college were 1.02-fold (95% CI: 0.87 to 1.19) more likely to report depressive symptoms when compared with those who had no more than a high school education.
Breastfeeding people with a BMI of 25.1–29.9 were less likely to be in the depressed group than women with a BMI of ≤25 and ≥30 (OR: 0.98, 95% CI: 0.74 to 1.30 and OR: 0.89, 95% CI: 0.79 to 1.01, respectively). Furthermore, depressive symptoms were 5.17-fold (95% CI: 3.78 to 7.06) more likely in breastfeeding people with diabetes mellitus or hypertension. Depressive symptoms in breastfeeding people who slept for 6–7 hours and ≥8 hours was 0.32-fold (95% CI: 0.28 to 0.36) and 0.38-fold (95% CI: 0.26 to 0.56) less likely when compared with those who slept for ≤5 hours. Finally, depressive symptoms in breastfeeding people who exercised for 2–4 times a week was 0.63-fold (95% CI: 0.49 to 0.81) less likely than those who exercised 0–1 times a week. By contrast, those who exercised ≥5 times a week were 1.02-fold (95% CI: 0.89 to 1.17) more likely to report depressive symptoms when compared with those who exercised for 2–4 times a week.
Discussion
This study sought to determine the incidence of depressive symptoms in breastfeeding people, as well as the factors affecting depressive symptomatology using the KCHS. We included 497 women aged 19–49 years who responded that they were breast feeding. A previous study21 reported the average age of breastfeeding people was 32.1 years old. In line with this, the average age was 32.9 years in this study. Breast feeding increases as women get older, live in rural areas and have more than one child.21 However, this study could not confirm these points because only breastfeeding people were targeted. Future studies should assess variables such as obstetric history, childbirth method, lactation method and time of breastfeeding cessation in consideration of these characteristics.
Studies on depressive symptoms using the PHQ-918 typically define individuals as having depressive symptoms if they score ≥10 points on this survey. However, this study used previous studies26 27 on pregnancy and childbirth to define depressive symptoms in individuals who scored ≥5. Using this cut-off, 19.4% women in our study were included in the depressed group, and 80.6% were included in the non-depressed group. Among the studies that defined depressive symptoms in individuals whose PHQ-9 score was ≥5, 12.2% women reported depressive symptoms within 12 months after childbirth,26 and 35.4% women reported becoming depressed during pregnancy and/or after birth.27 There are many variables to consider regarding depressive symptoms in women after childbirth, such as the time of diagnosis, medical history and socioeconomic status.3 In this study, the depressive symptoms of breastfeeding people were investigated using secondary data. In future studies, factors such as prepregnancy depressive state, obstetric history, lactation method, and time after childbirth should be considered. Repeated studies with other tools, such as the Edinburgh Postnatal Depression Scale, should be used to examine depressive symptoms in women.15 17
This study investigated depressive symptoms in breastfeeding people using PHQ-9. This is meaningful because this enables a comparison of depressive symptoms with other community population groups. Previous studies have used the PHQ-9 to report that 25% of adult women over the age of 19 were depressed18 and 43% of individuals with polycystic ovary syndrome were depressed.28 Therefore comparisons of studies that used the PHQ-9 are helpful as basic data when developing a nursing intervention programme for women’s depressive symptoms.
Previous studies conducted on women of childbearing age do not accurately determine the effect of age on depressive symptoms. In this study, we found that younger breastfeeding people were more likely to be depressed. Previous studies in middle-aged men10 and women who were assessed for 21 years after childbirth3 have shown that the younger the women, the more likely they are to experience depressive symptoms. In this study, women were stratified by age based on the mean and quartile data, which was used as a secondary variable. However, future studies should directly assess the effect of age on depressive symptoms in breastfeeding people. Moreover, in the current situation where the age of women giving birth is increasing, stratifying the effects by age is necessary.
A previous study has shown that depressive symptoms in middle-aged men is increased in those living in cities.10 In line with this, depressive symptoms was found to be 0.62-fold (95% CI: 0.51 to 0.76) less likely in women living in rural areas in this study. The reason behind this effect is unknown. It may be that people feel depressed in a city with higher-intensity living when compared with a leisurely rural life. This requires further investigation. Low-income levels are associated with depressive symptoms in several studies.9–11 This study also found that people with economic activity were less likely to be depressed. However, only the presence of economic activity was investigated in this study; future studies that specifically consider the type of work and working hours are required. Previous studies on depressive symptoms in women >19 years of age9 18 have shown that lower education levels are associated with increased depressive symptoms. However, in this study, the effect of education levels on depressive symptoms could not be determined due to the similar age characteristics of the women.
The effect of BMI on depressive symptoms in women varies. One study has shown that underweight women are more likely to be depressed.29 Moreover, a different study has reported that obese women are more likely to be depressed.11 By contrast, BMI was not identified as an influencing factor on depressive symptoms in breastfeeding people in this study. These women would not have controlled their weight for breast feeding; therefore, this may not have a direct influencing factor on depressive symptoms. Weight comparisons before pregnancy and after childbirth, and body image should be considered in future studies.
Previous studies have reported an effect of diabetes mellitus,20 but not hypertension,9 on depressive symptoms. In this study, breastfeeding people with diabetes mellitus or hypertension were 5.17 times more likely to be depressed than those without. In this study, there were 12 breastfeeding people with diabetes mellitus or hypertension among the participants; therefore, the influence of these diseases could not be accurately identified. In future studies, the effects of these diseases on breastfeeding people with depressive symptoms with comorbidities such as diabetes, hypertension and thyroid should be undertaken. In addition, breastfeeding people with chronic diseases such as diabetes or hypertension will need emotional support, the use of support groups and dietary habit counselling to prevent depressive symptoms and lead a healthy life.
Compared with those who slept for less than 5 hours, those who slept for 6–7 hours and ≥8 hours are less likely to be depressed. A previous study has reported no correlation between sleep time and depressive symptoms30; however, this study confirms the results from previous studies10 28 that low sleep can increase depressive symptoms. This study only investigated the relationship between depressive symptoms and sleep duration; therefore, the use of other questionnaire tools that consider sleep quality and environment should be considered in the future. In this study, women who exercised 2–4 and ≥5 times a week were less and more likely to report depressive symptoms when compared with those who exercised 0–1 times a week, respectively. Previous studies18 19 have reported that low physical activity is associated with depressive symptoms, the results of this study could accurately confirm this due to the limitations of secondary data. In the future, it will be necessary to investigate the effect of exercise on depressive symptoms through repeated studies considering the type of exercise and exercise time. Taken together, these data and future studies can be used to prevent depressive symptoms and promote physical health in breastfeeding people.
This study is significant because it investigated depressive symptoms and its influencing factors in breastfeeding people using Korea’s representative community health survey data. However, it has the following limitations. It used a cross-sectional design with secondary data; therefore, it is difficult to explain the temporal context of depressive symptoms in breastfeeding people and their related factors. In addition, this study used the PHQ-9 to measure depressive symptom in berastfeeding people, but further studies should consider the DSM-5, which contains updated information pertaining to mental health conditions. Finally, this study defined breastfeeding people without considering the period and method of breast feeding. Future studies will be need to define breastfeeding people as in previous studies.31
Conclusions
This study investigated depressive symptoms in breastfeeding people and its influencing factors using the KCHS. Our findings can be used as descriptive data for better understanding the effects of depressive symptoms on breastfeeding behaviours, as well as to develop health programmes that target breastfeeding rates, improving the health of birthing people and their infants.
Data availability statement
Data are available in a public, open access repository.
Ethics statements
Patient consent for publication
Acknowledgments
The authors thanks those individuals who participated in this study.
References
Footnotes
Contributors Conceptualization, J.S.; methodology, J.S.; validation, E.L.; formal analysis, J.S.; writing—original draft preparation, J.S.; writing—review and editing, E.L. All authors have read and agreed to the published version of the manuscript.
Funding The authors have not declared a specific grant for this research from any funding agency in the public, commercial or not-for-profit sectors.
Competing interests None declared.
Patient and public involvement Patients and/or the public were not involved in the design, or conduct, or reporting or dissemination plans of this research.
Provenance and peer review Not commissioned; externally peer reviewed.