The family structure in Korea has changed from the traditional large family center to the nuclear family form due to industrialization and urbanization, and recently, the number of one-person households living alone, and the nuclear family has increased rapidly [1]. According to the National Statistical Office, more than one-third of Korea’s population is estimated to be one-person households: 15.5% in 2000, 29.3% in 2018, and 34.3% in 2035 [2].

The increase in one-person households is an inevitable social phenomenon caused by changes in social structure such as industrial reorganization and changes in values. Yet as social security and tax, housing, and consumer markets are built around general households, one-person households are excluded or disadvantaged and one-person households are more likely to be at greater risk than ordinary households in various areas of life, including fear of aging and safety [3].

Along with the increase in the number of one-person households, the rapid increase in the number of elderly one-person households due to the growing age levels has been a notable phenomenon. In 1994, the proportion of the elderly living alone was 13.6%, while in 2018 it was 19.4%, an increase of about 6% across 18 years [4]. Compared to other elderly groups, one-person households have a problem in that they need to maintain their own lives independently because there is no family to support them. It was reported that one-person elderly households were more likely to be threatened by serious psychological and social problems due to financial problems, mental health problems such as depression, low nutrition and physical health, and lack of health promotion [5,6]. Especially, among the one-person households, the need for medical care is expected to be an important issue compared to other age groups, as the elderly group’s lower socioeconomic status is combined with their health problems. The problem of increasing elderly medical expenses is that 14% of the elderly still spend 40% of their health insurance expenditures, and are expected to have the highest expenditure causing social and pension burden in the future in an aged society [7]. Among the issues caused by the increase of one-person households due to social change, the provision of measures for health problems and primary medical needs of one-person elderly households is the most important policy issue to be addressed in the future.

Thus far, diverse studies have been conducted due to the increasing social interest in one-person households. Although there are many studies focusing on socio-demographic factors [3], nutritional behavior [8,9], quality of life [5,10], and satisfaction [6], there are only few studies focusing on health factors. Such studies only conducted short analysis for general health status [1,11,12], mental health [13-18], and oral health status. In addition, since only one one-person elderly household is analyzed, there are not many studies comparing the characteristics of one-person and multi-person households. Most studies involving two groups did not use comparison models between groups [11,12,14,17] and, thereby, the differences between the two groups have not been systematically investigated. Therefore, relevant studies are urgent as the problems-based alternatives can be sought only after in-depth understanding of the health problems and medical needs of one-person elderly households.

This study aimed to identify the health and primary medical needs problems of one-person elderly households by using the 2017 Community Health Survey data. Specifically, the health needs and problems of one-person elderly households and multi-person households were compared by analyzing the health behavior, health status, disease prevalence, medical needs, and medical access to the identified health care needs and problems of one-person elderly households.

In order to meet the policy demands of increasing social interest in one-person households due to the rapid increase in one-person households, this study investigated the health and medical needs of one-person elderly households, which are health-vulnerable groups. For this, we compared and analyzed the health behaviors, health status, and medical needs of one-person and multi-person households. About 16.6% of the total analysis subjects aged 60 or older were one-person households and compared to the statistics reported in 2018 where 19% of the elderly aged 65 were one-person households, it was assessed to be at a similar level as the nationwide statistics [18].

As a result of comparing socio-demographic characteristics of one-person and multi-person households, the proportion of females in one-person households was 74.3%, higher than that in multi-person households (50.3%). The higher trend of females in one-person households compared to multi-person households shows the same results in all studies involving one-person households [10,11,21]. The reason for this is that husbands are generally older than their wives and females have a longer average life span than males. Therefore, the gender ratio of the elderly population is thought to be due to the trend of decreasing men and increasing women, which may be affected by the difference in remarriage rates [5]. However, this large difference in gender characteristics may affect the comparison of other characteristics, which is a confounding variable. Therefore, when comparing household characteristics, sub-analysis was conducted by dividing into male and female.

Age, which is a key socio-demographic variable, was significantly higher at the age of 72.2 for one-person household than multi-person households. In terms of household income, the one-person households had lower incomes, and lower educational levels with 56.0% of the students being elementary school graduates or below. These interfamily characteristics showed results in the same context as other studies related to one-person households [1,11] and showed the same trends when compared to men and women.

Regarding smoking, 25.7% of one-person households and 39.8% of multi-person households reported smoking, thus the percentage of smokers was significantly higher for multi-person households than one-person households. In the gender sub-analysis, the proportion of smokers in the one-person household was significantly higher than that of the multi-person household. In case of drinking, 74.4% of multi-person households drank, which was higher than one-person households, and the same result was found in gender sub-group analysis. This is consistent with the finding of Kim [21] that the elderly living with spouses drank more than those who did not live with spouses. In terms of “days of muscle exercise” and “days of flexibility exercise,” the households that “never exercised” were significantly higher in the one-person households than in the multi-person households. Kim [21] found similar results that those who exercised more than 3 times a week were more likely in the elderly who lived with their spouses compared to those who did not. Elderly people in Korea have predominantly spent their youth in a poverty-stricken society, and due to the lack of methods and facilities to enjoy leisure activities, they frequently spend their free time tediously without properly utilizing their leisure time. In the case of the elderly people living alone, there are differences in social interaction, exercise, and leisure activities participation forms depending on the presence of a spouse or cohabiting family. The level of active leisure participation varies according to economic and health conditions as well. Active leisure participation during old age can restore the self that was lost due to the losses of old age by forming a formal network of relationships and fulfilling its role. There is a need to work to increase participation in productive leisure activities in the sense that it is a major means of promoting physical and mental health [22].

As an indicator of nutritional and dietary behavior, the “usual salt intake level” was slightly higher in one-person households than in multi-person households with those responding as “eating salty” higher and this is in agreement with the finding of Jang and Hong [8] about half the one-person households agreeing that “they usually eat spicy and salty foods.” The ratio of eating spicy and salty foods is high. As a proxy for nutritional knowledge, the question of “perception of nutrition labeling” was shown to indicate that since the one-person household is lower than the multi-person household, the nutritional knowledge of the one-person household is somewhat lower than that of the multi-person household. Through this, the nutritional status of the elderly people living alone should be considered as a priority, and practical programs and health management support based on the health needs of the elderly people living alone should be constructed [23].

The proportion of one-person households that responded that the “subjective health level” was “bad” was high compared to the multi-person household group, and the “subjective stress level” and “depression” was also significantly high for one-person household group. This is the same as the result of the findings of Jung [11] that subjective health, stress, and subjective oral health had a higher proportion of elderly people living alone saying it is bad when compared to those living with family members. Moreover, the proportion of one-person households responding that they had a disease was significantly higher than that of multi-person households, which is consistent with the findings of Kim [10]. In conclusion, one-person households in the elderly population assessed that the subjective and objective health levels were less than the multi-person households.

Sleeping time was significantly lower in one-person households than in multi-person households, which is consistent with the finding of Han et al. [14] that elderly people living alone sleep 6.05 hours a day, less than 6.59 hours a day for couple elderly. This is because most of the elderly people living alone lack the economic and social support given by the cohabiting families, thus become easily neglected to behaviors to maintain the health of the mind and body, and consequently, this leads to deterioration of physical health or social psychological isolation [22].

As an indicator of the medical needs in terms of mental health, “suicide experience” and “suicide attempt experience” were of a higher proportion in one-person households than multi-person households. This is consistent with a study reported by Park et al. [13] that with one-person households, women, low income and lower educational background, the higher the suicidal thoughts. This study assumed that there was a problem with mental health and one required mental health management and medical requirement in the case of “suicide experience” and “attempting suicide.” These indicators were used as substitute indicators suggesting “needs for mental health services.” The logical rationale for this approach starts from the claim that “suicide attempts” are medical conditions to be treated with behaviors in unhealthy conditions, including disease such as mental illness, and preventable medical and health problems [24]. Bae and Woo [25] pointed out that intentions to commit suicide or attempts to commit suicide frequently lead to suicide; hence, they are signs of suicide and require preventive management and medical measures. In particular, mental health problems such as depression and stress have been proposed as direct factors for suicide of the elderly [26] while these mental health problems are frequently encountered in the field where primary healthcare is provided, and must be emphasized as an issue that primary healthcare doctors should pay particular attention to [27]. Through empirical studies, Luoma et al. [28] corroborated that 90% of people who died from suicide used primary healthcare a year before death, and 76% visited a primary healthcare institution within 1 month of suicide. They suggested that addressing mental health and suicidal intention as a sign of suicide should be an important concern of primary healthcare doctors. As the elderly living alone are vulnerable to mental health conditions compared to multi-person households, and there are no other household members to assess suicidal signs, it is necessary to pay special attention to the mental health and suicidal signs of single-person elderly households in the primary healthcare field.

As an indicator of medical accessibility, the percentage of not receiving “oral examination,” “health examinations,” and “cancer examinations” was higher in one-person households than in multi-person households. The proportion of not receiving “dental care” and “needed medical care” experiences was also higher among one-person households. This is similar to the finding of Kim [21] that the rate of health examination and cancer examinations of the elderly living with their spouses is higher than that of the other group. These findings indicate that elderly people living alone have less access to medical care and less information than those living together. The recognition of the care service in the country is also attributed to the low result. However, as for the influenza immunization rate, one-person households were significantly higher than multi-person households, and a detailed analysis was conducted to find out the reason. Since there are more health centers than single hospitals for one-person household inoculation sites, it is possible that health institutions including public health centers have actively prevented the residents of rural areas, but further clarification is needed.

Logistic regression analysis was performed by clustering the various variables into groups of variables with the same meaning, and as a result, even though the age and gender were included in the model and controlled, the one-person household consumed 0.94 times less “bland food” than the multi-person household. The “nutrient labelling perception” also had 1.55 times higher “no perception” proportions compared to “perception.” The disease score was calculated by coding 1 for the cases of diagnosis of four diseases; hypertension, diabetes, arthritis, and cataract. The higher the disease score, the greater the number of diseases. The one-person household group had a “combined disease score” of 1.02 times higher than the multi-person household group. This is similar to Kim and Kim [16], who reported that elderly people living alone had more than three diagnosed disease compared to those not living alone and the research of Sohn [17] that found the chronic disease burden was 7.7 points for the elderly living alone and 4.8 points for the elderly not living alone. As such, most of the previous studies related to diseases were analyzed based on the presence of chronic disease, depression, and quality of life. There was no previous study using disease scores, so the above results could not be compared with other studies.

Sleeping time was shorter in one-person households than in multi-person households. Awareness of health and awareness of oral health were significantly worse, and awareness of depression was high. These results were similar to those of Jung [11] where there is a high percentage of elderly living alone with bad subjective health and subjective oral health. It also supports the research of Ryu and Park [29], which claims that family is one of the most important factors affecting health status. Therefore, it is necessary to induce and improve the environment that elderly live in with their families rather than to stand alone [11]. “Mental health needs” was also 1.24 times higher, and these results indicate that the elderly living alone had a higher suicidal thought rate than elderly couples, as corroborated by Han et al. [14] It also showed similar results as the research of Jeon and Lee [15] and Kim [30], which showed that suicidal thought experience is higher for those without a spouse. The “level of not receiving required services related to oral” was 1.03 times higher for one-person households. This was similar to the result of Jung [11], which showed that the percentage of elderly who lived alone was 0.33 times less than the elderly who received oral examination. The “level of not receiving health examinations and medical use service” was 1.17 times higher for one-person households than the multi-person households.

In conclusion, one-person households are considered to have poorer overall health behaviors, such as nutritional behaviors, exercise behaviors, drinking and smoking behaviors, and poorer subjective and objective health levels than multi-person households. Furthermore, albeit the high requirement for mental health and medical services, such as suicide attempts, the high rate of not receiving services indicated high barriers to receive and access health care. The implications from these results are as follows. First, a variety of programs are needed to prevent health problems and improve health behaviors through appropriate education and training for elderly one-person households. Second, along with the high medical service needs, policy efforts are needed to profoundly investigate obstacles hindering actual medical use and to solve these obstacles. In particular, since the demand is not being properly connected to medical use compared to high needs of primary healthcare, it is necessary to devise institutional measures to enable continuous medical care for the single-person elderly households in the primary healthcare.

The purpose of this study was to analyze the socio-demographic characteristics, health behaviors and health status, medical needs and accessibility of Koreans in the one-person and multi-person households. Although the data were analyzed using Korean representative data, there are some limitations. First, since this is a cross-sectional study that examined health level, medical access, etc. at the time of survey in 2017, there is a limitation that it is not possible to causally interpret the difference between one-person and multi-person households. Second, recall bias may occur because the survey is a 1:1 interview. Third, there are limitations in applying stratification variables, cluster variables, and weight variables in research and analysis, thus although it is a study of all citizens, it is not a perfect representation of the entire population. Fourth, there is a small percentage of households in the one-person household, so there is a difference in the number of subjects between the comparison group and the control group. Hence, in statistical analysis, there is a possibility of underestimation and false negatives in some items.

Despite the above limitations, this study is meaningful in the following aspects. First, it is easy to generalize and apply the results to all citizens by utilizing the data of Community Health Surveys that have undergone strict quality control. Second, unlike previous studies analyzing mental health and quality of life of the elderly, the differences in characteristics were derived by directly comparing the health behaviors and health and medical factors between one-person and multi-person households. Comprehensive and direct comparison of health and medical factors revealed the medical vulnerability and characteristics of the single-person elderly households. Therefore, as a risk group, they revealed the unsatisfied medical needs to be improved for these single-person elderly households. Such data can be applied as basic information to understand these groups for primary medical doctors who predominantly treat single-person elderly households and can also be used as basic data for policy development in order to solve unsatisfied medical care problems.

One-person elderly households are the overlapping areas of two social challenges, namely, the increase in the proportion of one-person households and the expansion of the elderly population. They are considered as the most vulnerable class and this research corroborates such evidence succinctly. In particular, the increasing problem of elderly medical expenses is considered to be the first priority to solve the problem of sustainable health insurance financing. Preventive efforts concerning single-person households and diverse policy efforts to minimize obstacles to the use of medical services should be urgently devised. In particular, considering the characteristics of medical necessities of single-person elderly households, as sustainable medical care is important, policy incentives are required to take interest in these groups and effectively manage these groups in primary healthcare fields.