Relationship between Perceived Health Status and Health Practices in the General Adult Population in Japan ()
1. Introduction
In 1972, Belloc and Breslow first reported a strong relationship between physical health status and seven lifestyle practices for physical health [1] . They found that these seven health practices were significantly associated with a general index of physical health. Breslow’s seven health practices (7 - 8 hours sleep regularly, maintaining proper weight, moderate or no use of alcohol, regular physical activity, not eating between meals, eating breakfast, and never smoking cigarettes) are widely accepted in Western and Asian countries. Over the past 40 years in Japan, many studies have been published regarding such issues [2] -[7] , and these seven health habits have been used to assess health practices and to test the association between health practices and health status, including depressive states and complaints [8] -[15] . Furthermore, the Japanese government’s public health service policies and Health Japan 21 refer to these seven practices with respect to prevention of chronic disease and enhancement of quality of life in Japanese citizens [16] [17] .
The World Health Organization’s definition of health refers to the “complete status of physical, mental, and social well-being.” This definition contrasts with early studies where health status was determined via mortality rates [18] -[20] and chronic conditions (physician ratings and functional ability) [21] [22] . Recently, perceived health has been used to measure health status [23] [24] . Kaplan et al. suggested that perceived health held the key to understanding other psychosocial influences on health. This is a simple, direct, and inclusive method, because it is based on the respondent’s perceptions [25] .
Several studies have reported an association between lifestyle and perceived health status by sex [26] , age group [26] -[31] [34] [35] , occupation [27] [28] [33] , ethnicity [28] [30] [35] , household income, different chronic conditions [34] [35] , and personality traits [26] [36] . Despite such studies having clarified the overall associations among perceived health status (self-reported health status) and lifestyle (physical activity, drinking habits, smoking habits, eating habits, nutrition, driving safety, leisure-time activities, and intensity of each physical activity), surprisingly little is known about the relationship between Breslow’s seven health practices and perceived health status.
In Lester and Breslow’s research, physical health status was measured along a spectrum, ranging from severe disability, chronic conditions, impairment, symptoms, to high energy levels [37] [38] . However, it is difficult to use this measure in a community public health service. In the present study, we evaluated the usefulness of Breslow’s seven health practices to subjectively assess physical and perceived health status, using a perceived health scale containing all seven health practices.
The purpose of this study was to explore the relationship between perceived health status and Breslow’s seven health practices in the adult population of Japan, and to find effective and simple (low cost) suggestions of good daily life habits for health and longevity.
2. Methods
Data were gathered from the 2011 questionnaire research “Health Kumamoto 21”. The present study was con ducted after receiving informed consent from the subjects and approval from the ethics committee of the Kumamoto University Faculty of Life Sciences (approval number 408). This study was performed in accordance with the Declaration of Helsinki.
2.1. Study Population
A cross-sectional research method was adopted. The data used in this study were sourced from the ongoing Health Japan 21 program in Kumamoto Prefecture, Japan. A total 5585 adult residents were selected on the basis of a stratified systematic sample of city housing units and using area probability sampling methods. Information for 2011 about health status and lifestyle was obtained from mail-back questionnaires. Completed questionnaires were received within 2 weeks from 2519 respondents (45.1%), which included 1159 men and 1360 women aged between 20 and 74 years. To ensure anonymity, no name was required on the questionnaire. Table 1 lists demographic variables including sex, age, employment status, family structure, perceived health status, life satisfaction, depression, and social network, as well as Breslow’s seven health practices. Employment status was rated on a 5-point scale: made redundant (1), unemployed (2), unstable employment (3), nonworking spouse and/or children (4), and employed (5). Perceived health status was measured by responses to the question, “All in all, would you say your health is excellent, good, fair, or poor?” [23] . Responses were rated on a 4-point scale: excellent (4), good (3), fair (2), or poor (1). Life satisfaction scores were measured by responses to the question, “How satisfied are you with your daily life?” [39] . Responses were rated on a 5-point scale: very dissatisfied (1), dissatisfied (2), neither dissatisfied nor satisfied (3), satisfied (4), or very satisfied (5). Depression scores were measured by responses to the question, “Do you feel any stress in your daily life?” [39] . Responses were rated on a 5-point scale: very strongly (1), strongly (2), neither stressed nor unstressed (3), slightly (4), or no stress (5). Social network participation was measured by a composite index of items relating to contact with friends and relatives, and membership in various kinds of group activities. Social network scores were based on three questions concerning the extent and frequency of three types of social ties (close friends/relations, involved in the
Table 1. Variables in the analyses of health practices and perceived health status.
community, and joining group activities) [39] . Health practice status was based on Breslow’s seven health practices [1] . The health practice score represents the number of current health practices (0 - 7). Participants self- reported their weight and height, which were used to calculate BMI.
2.2. Analysis
Data were analyzed using the IBM SPSS Statistical Package, Version 20.0 (IBM Corp., Armonk, NY, USA). Participants were divided into six age groups: 20 - 29, 30 - 39, 40 - 49, 50 - 59, 60 - 69, and 70 - 74 years of age. Participants were also was divided into three groups according to the number of regular health activities currently practiced: zero to three (0 - 3), four to five (4 - 5), and six to seven (6 - 7).
Differences in the percentages among the health practice groups, age groups, and sex groups were tested using chi-squared tests. Differences in mean values among health practices, age, and sex groups were tested for significance with one-way analysis of variance, multiple comparison procedures using Tukey’s HSD test, and t-tests. Pearson’s correlation analysis was used to determine the relationship among all associated variables. Multiple stepwise regression analysis was used to examine the effects of the independent variables (age, BMI, Breslow’s health practices, life satisfaction, depression, social network, family structure, and employment status) on the levels of perceived health status. All data are given as mean ± SD. A p-value < 0.05 was considered significant.
3. Results
Based on Breslow’s seven health practices, 59.0% of participants (men, 60.2%; women, 57.9%; p > 0.05) regularly had 7 - 8 hours sleep per night; 56.4% (men, 55.1%; women, 57.5%; p > 0.05) maintained a proper weight; 86.6% (men, 77.2%; women, 94.4%; p < 0.001) had moderate or no alcohol use; 26.5% (men, 29.6%; women, 23.9%; p < 0.05) engaged in regular physical activity; 37.6% (men, 51.5%; women, 26.0%; p < 0.01) reported not eating between meals; 80.9% (men, 77.4%; women, 83.8%; p < 0.05) reported eating breakfast every day; and 75.7% (men, 59.0%; women, 89.7%; p < 0.001) reported never smoking cigarettes.
Table 2 reports data for the age, sex, and health practice groups. Mean age did not differ between men and women for all age groups. The total percentage in the 4 - 5 health practices group (men, 45.0%; women, 55.5%)
Table 2. Demographic and participant groups (n = 2519).
*p < 0.01, 4 - 5 vs. 0 - 3; #p < 0.05, 6 - 7 vs. 0 - 3; $p < 0.05, 6 - 7 vs. 4 - 5; Significant differences measured using chi-squared test.
was significantly higher than the 0 - 3 (men, 33.4%; women, 25.0%) and 6 - 7 (men, 21.6%; women, 19.5%) groups for both men and women (p < 0.05).
Tables 3-5 report data of perceived health status, life satisfaction, and BMI according to health practice, sex, and age groups. For both men and women, mean scores of perceived health status in the groups of 4 - 5 and 6 - 7 current health practices were significantly higher than those in the 0 - 3 group, and the 6 - 7 group was significantly higher than the 4 - 5 group. There were no significant differences between men and women or among age groups (Table 3). As for perceived health status data, the life satisfaction mean scores of the groups who engaged in 4 - 5 and 6 - 7 practices were significantly higher than those of the 0 - 3 group, and the 6 - 7 group was significantly higher than the 4 - 5 group. The total life satisfaction mean score for women was significant higher than that for men. There were no significant differences among age groups for men and women (Table 4). The total mean BMI variable was significantly higher in the 0 - 3 group than the 4 - 5 and 6 - 7 groups, and the 4 - 5 group was significantly higher than the 6 - 7 group. Furthermore, mean scores of the variables perceived health,
Table 3. Scores of perceived health status by health practices, age, and sex groups.
ap < 0.05, 6 - 7 vs. 0 - 3;bp < 0.05, 6 - 7 vs. 4 - 5; cp < 0.05, 4 - 5 vs. 0 - 3; **p < 0.01; ***p < 0.001; Significant differences among the health practices groups measured using Tukey’s HSD test.
Table 4. Scores of life satisfaction by health practices, age, and sex groups.
ap < 0.05, 6 - 7 vs. 0 - 3; bp < 0.05, 6 - 7 vs. 4 - 5;cp < 0.05, 4 - 5 vs. 0 - 3; #p < 0.01, women vs. men; **p < 0.01, ***p < 0.001; Significant differences among the health practices groups measured using Tukey’s HSD test.
Table 5. Mean BMI variable by health practices, age, and sex groups.
ap < 0.05, 6 - 7 vs. 0 - 3;bp < 0.05, 6 - 7 vs. 4 - 5; cp < 0.05, 4 - 5 vs. 0 - 3; **p < 0.01; ***p < 0.001; Significant differences among the health practices groups measured using Tukey’s HSD test.
life satisfaction, and BMI were better in the 6 - 7 group than in the 4 - 5 and 0 - 3 groups. There were no statistically significant differences in the 70 - 74 age group (Tables 3-5).
Pearson’s correlation analysis showed a significant positive correlation between perceived health status and health practices (r = 0.0.229, p < 0.001), life satisfaction (r = 0.279, p < 0.001), social network (r = 0.089, p < 0.001), and employment (r = −0.123, p < 0.001); and a significant negative correlation for age (r = −0.058, p < 0.01), BMI (r = −0.093, p < 0.001), and depression (r = −0.177, p < 0.001). There was a negative correlation between age and life satisfaction, but it was not statistically significant (Table 6).
A multiple stepwise regression analysis of the health practices scores was performed to determine which independent variables were predictors of perceived health status for all participants. With seven independent variables in the regression model, the analysis produced the following results: 14.1% (p < 0.01) for all participants, 17.5% (p < 0.05) for men, and 12.3% (p < 0.01) for women (Table 7).
Several highly significant correlations were found for the independent variables; life satisfaction, seven health practices, employment status, and social network were found to have significant positive effects on levels of perceived health status. By contrast, age, depression, and BMI were found to have significant negative effects on perceived health status. BMI had no effect on levels of perceived health status among men. Both BMI and social network had no significant effect in women.
4. Discussion
Health is a multi-dimensional concept that is usually measured in terms of: 1) life expectancy (using international comparisons); 2) healthy life expectancy; 3) years of potential life lost (using international comparisons); 4) physical and mental illness; 5) self-rated health status; 6) limitation of activity; and 7) chronic disease prevalence [40] . More recently, self-rated health status has been used as a measure of how an individual perceives his or her health by rating it as excellent, very good, good, fair, or poor.
Perceived health status is a reliable and valid indicator for general health and many morbidities and mortality in adolescents [12] [41] -[43] , students [44] , working-age populations [3] [15] [45] [46] , older adults [23] [47] -[49] , middle-aged adults [50] [51] , and general populations by follow-up study [25] . Perceived health status―also called self-rated health status, self-rated general health, or self-reported health―is a frequently used measure of subjective morbidity. There are two health status measures; one is a single-item self-perceived general health question, and the other is a multi-item index. If we compare the single-item and multi-item measures, the single-item (“All in all, would you say your health is excellent, good, fair, or poor?” and/or “very good, good, moderate, bad or very bad?”) is simpler and has been frequently used in research published recently in epidemi-
Table 6. Pearson correlation matrix of variables.
*p < 0.05; **p < 0.01; ***p < 0.001.
Table 7. Multiple analysis of perceived health status and life satisfaction for other variables.
*p < 0.05; **p < 0.01; ***p < 0.001; using stepwise regression analysis.
ologic and public health journals. In some surveys, more than five answer categories have been used; other surveys use fewer categories. In our study, a four-answer question (“All in all, would you say your health is excellent, good, fair, or poor?” [23] [52] ) was used to survey health status.
Lifestyle has been defined as any activity undertaken by an individual. It can include health behaviors and risk behaviors, which are both often related in clusters to a more complex pattern of behaviors referred to as lifestyle. An individual lifestyle assessment is usually used to self-report behaviors such as eating habits, smoking habits, drinking habits, nutrition, driving safety, sleep patterns, leisure-time activities, and physical activity. Although many previous studies have reported a relationship between lifestyle and perceived health status, there are many lifestyle assessment variables [26] -[36] , and scales of perceived health status are also varied or complex [27] [28] [33] [36] . In this study, we reviewed previous studies, especially those of Breslow. Our objective was to clarify the relationship between perceived health status (excellent, good, fair, or poor) and Breslow’s seven health practices among Japanese adults, to find effective and simple health behaviors for improved health as well as for epidemiological study.
With the single-item self-rated general health question, the respondents’ answers are not only a reflection of their “objective” health status but are also influenced by the norms and expectations of individuals, groups, and societies about health. Kaplan [25] reported that there is a relationship among perceived health status, physical health status, and mortality. In that study, the variables of physical health status were constructed from individual reports of disability, chronic conditions, symptoms, and energy levels. Measuring those variables takes some time and involves complex analysis. It is neither convenient nor cost-effective for public health staff to collect such data in general community health care settings.
Nedra’s study [37] on the relationship between health practices and mortality reported that men and women engaged in six or seven of the health practices described here had greater life expectancy than those practicing three or less [40] . Our data also show that those engaging in more than four practices have a higher perceived health status, greater life satisfaction, and a healthier BMI than those who only practice three or fewer.
The results of the Pearson’s regression analysis found a significant relationship between perceived health status and these seven health practices, and also for BMI. The same was true in the multiple regression analyses, which indicated the independent impact of the seven practices and BMI on perceived health status. Furthermore, life satisfaction, employment, age, depression, and social network are significant factors in respondents’ perceived health status.
4.1. Limitations
This study had several limitations. First, the questionnaire response rate was 45.1%, which is lower than the typical 50% - 70% rate [52] . Previous studies have shown that there are various techniques to increase the response rate of mail surveys, for example, providing incentives for respondents, follow-up contact via telephone and postcard, and shorter questionnaires [53] -[55] . Although we used a kairanban (a regional newsletter and notice board) to remind respondents to return their questionnaires, we did not provide any incentive to do so. The six-page questionnaire contained more than 40 items; this may therefore be the reason for the low response rate. When compared with respondents, the small group of non respondents contained more young people (30.3% were aged 20 - 39 years) and older people (33.3% aged 70 - 74 years). Second, this study did not cover Japan’s entire adult population because we did not survey those over 75 years old. Monitoring the health habits of older adults is an important job for community health nurses in Japan.
4.2. Future
It is clear that perceived health status is associated with the seven health practices in this study, and that regular engagement in more than four of these practices results in a higher perceived health status. However, further analyses would be valuable to examine this issue in greater detail. An example is investigation of which health practices should be included in the “more than four” group and which in the “less than four” group. The nature of the interaction between chronic condition variables with respect to their impact on perceived health status and health practices must be clarified and should be the subject of further exploration. It is also important to research the best way to encourage an environment in which to create good health habits in Japan.
5 Conclusion
Our findings demonstrate a strong relationship between perceived health status and Breslow’s seven health practices. These results support the use of such practices to enhance perceived health status and to encourage good habits for improved health and longevity in the community.
Acknowledgements
We would like to thank all the participants in this study, and the technical support staff for data analysis and clerical support.