Social inequalities in health
- There are substantial social inequalities in health in Norway, especially between educational groups.
- Women and men with the highest education live 5-6 years longer and have better health than those with the lowest education.
- The differences are increasing, especially among women.
- Within Oslo, life expectancy varies by up to eight years between districts.
- Inequalities in health in Norway are larger than in many other European countries.
About social inequalities
When comparing groups in society, we find systematic differences in health. The higher the education and income the group has, the higher the proportion of the group’s members have good health (Norwegian Directorate of Health, 2005; Huisman, 2005). These are known as social inequalities in health.
Health improves with every step on the socioeconomic ladder. A higher education is associated with better health. The same applies to income. Not only does the next poorest have better health than the poorest, we see that the richest on average have slightly better health than the next richest.
Social inequalities in health apply to almost all diseases, injuries and ailments. We see differences among all age groups and among men and women. These involve many lost days and years of good health and quality of life.
Social inequalities are unfair and represent a loss for individuals, families and society. The total health potential of the population is not fully utilised.
Here we describe specific examples of socioeconomic differences in health and life expectancy in Norway.
Health and life expectancy increases with increasing education
Figure 1 shows the life expectancy (at 35 years of age) in Norway, 1960-2015, grouped by educational achievement. As the figure shows, men and women with higher education had the highest life expectancy in the period from 1960 til 2015.
Estimates of life expectancy at 35 years in 2015 show that (norgeshelsa.no):
- Men with university or college education have a 6.4 year longer life expectancy than men with lower secondary education.
- For women, the difference is 5 years.
- If someone is married, has a university or college education and has a spouse with the same level of education, their life expectancy is 8–9 years higher than for unmarried people who have only completed lower secondary education (Kravdal, 2017).
Figure 1. Life expectancy for women and men aged 35 in Norway, 1961–2015, grouped by education level. Source: 1961-1989: Steingrimsdottir (2012), 1990-2015: Statistics Norway/Norhealth
The level of the figures from Steingrimsdottir (2012) has been slightly adjusted for comparability.
We see that those who completed higher education had the highest life expectancy throughout the entire period from 1961 to 2015.
Increasing social inequality in life expectancy
In the decade from 1960 to 1970 there was a decrease in expected remaining life years among men in the lowest educational groups.
From 1970 to 2000, life expectancy increased significantly in all groups but most in the groups with the highest education. Until around 1980, women in all three educational groups had a higher life expectancy than men, see Figure 1, women to the left. This is no longer the case. Women with lower education are lagging behind and have had the poorest development (Steingrimsdottir, 2012).
Figure 2 shows the difference in life expectancy between 35-year-olds with lower secondary education and those who have higher education in the period from 1961 to 2015. The figure shows how the difference is increasing for women over the entire period. For men, the difference increased up to 2004, followed by a levelling out until 2009. Since then, the trend appears to be increasing.
Figure 2. The difference in expected remaining-life years at 35 years of age between those with lower secondary and higher education in the period 1961-2015. The figure shows the annual figures for the entire period (dots) and the 5-year moving average, which is based on annual figures and the four preceding years (solid lines). Source: Norhealth.no
The Public Health Report has a chapter on life expectancy.
Inequalities in health among children and adolescents
There are differences in health at all ages, among children, adolescents, adults and the elderly.
- There is higher infant mortality, lower birth weight and a higher risk of premature birth in groups with lower education (Dahl, 2014).
- There is a higher proportion of children and adolescents who report poor health in families with lower socioeconomic status than higher socioeconomic status (Elstad, 2012).
- Adolescents from homes with high socioeconomic status more frequently report a higher quality of life, better health and less psychological distress than children from homes with lower socioeconomic status (NOVA, 2016). The differences are particularly evident among girls, according to figures from the Ungdata study in 2014 and 2015.
The Ungdata study is based on responses from 118 000 schoolchildren aged 13-19 in 183 Norwegian municipalities (NOVA, 2016). Socioeconomic factors were measured through questions about parental education, access to books and material resources in the home. The fifth of the adolescents with the highest score were defined as the group with high socioeconomic status (NOVA, 2016).
Health inequalities among the elderly
There are few Norwegian studies of socioeconomic differences in health among the elderly. Perhaps it was assumed that the strongest survive, regardless of socioeconomic background. Consequently, there would be small differences among those who have lived long lives. However, recent studies suggest that differences continue into old age (Moe, 2012; Kinge, 2015a)
Among the eldest there are differences in expected remaining life years:
- Among 65-year-olds, the expected remaining lifetime is about 4 years longer for those who have a higher education than for those with lower education.
- 90-year-old men and women with higher education can expect to live three months longer than men and women with lower secondary education.
Statistically, elderly people with low socioeconomic status have more illnesses and health problems than those with high socioeconomic status. The "World Report on Ageing and Health" highlights that this group also has the fewest resources to take care of their own health (Beard, 2015).
Social inequalities in health and disease
Social inequalities in health apply to virtually all diseases, injuries and disorders (Dahl, 2014). Social status affects health, although the reverse can be the case, that health problems can interfere with education and career, and consequently lead to a low socioeconomic position. Meanwhile, financial and work problems can increase the risk of health problems and disease. Results from different studies show, for example, that:
- In groups with lower education there is a much larger proportion who report poor health than in groups with higher education (Kurtz, 2013)
- Musculoskeletal disorders are more common among people with lower socioeconomic status, and figures from the Lifestyles studies in Norway indicate that there is an association that has become stronger over time (Dahl, 2014).
- For those who have only completed lower secondary education, the risk of COPD is three times that of those with a university education. (Bakke, 1995; Johannessen, 2005; Næss, 2004).
- There are major differences between education groups in the number of first heart attacks, according to figures from the CVDNOR project from the period 1994-2009 (Igland, 2014).
- Type 2 diabetes is more common in groups with shorter education than in groups with longer education (Agardh, 2011; Joseph, 2010).
- There is a clear association between chronic pain and socioeconomic factors like education, income and professional status. Prevalence is highest in the lowest socioeconomic groups (Bonathan, 2013).
- People with low socioeconomic status are at higher risk for mental disorders (WHO, 2014).
Socioeconomic differences in lifestyle
Studies show that lifestyle habits such as smoking, diet and physical activity often follow educational and income levels. That means that those who have higher education and higher incomes have a more favourable lifestyle than those with lower education and income. For example, a study of 11-year-olds from the Oslo area shows that children's consumption of sugary drinks is related to parental educational levels. The same applies to the consumption of fruit and vegetables (University of Oslo, 2016).
Smoking is closely related to education. The proportion of smokers falls steadily with increasing education see smoking and snus
While only 5 per cent of 25-74-year-old men with college or university education are daily smokers, the proportion is 25 per cent in the group with lower secondary education, see Figure 4a. These figures are compiled by NIPH based on data from Statistics Norway.
The differences are as great among women. Approximately 22 per cent of women with lower secondary education (grunnskole) smoke, compared with 5 per cent of women with higher education, see figure 4a.
Figure 4a. Daily smoking among women (kvinner) and men in the 25-74 year age group by highest educational achievement, 2017. Per cent, standardised. Lower secondary, upper secondary and higher education. Source: Norhealth, Statistics Norway.
Figure 4b shows that daily smoking among women and men aged 25-74 years by educational level for the period 1975 to 2015.
Figure 4b. Percentage of daily smokers aged 25-74 years by educational period 1975-2015. The figures are adjusted for European standard populations in the ten-year age groups (25-34, 35-44, 65-74 ...). Source: Smoking Habits Survey by Statistics Norway.
We see that there are major differences between educational groups. Among women, we also see that the proportion of daily smokers declined first in the group with the longest education (orange curve) and last in the group with lower education (purple curve with approximate peak in 1995).
In 1996, the age limit for buying tobacco was raised from 16 to 18 years. In 2004, a total ban on smoking in all public places was introduced. Several regulatory and legislative changes have followed, including a law on tobacco-free schools and childcare centres in 2013.
In parallel with public health initiatives aimed at smoking, there have been major changes in opinions of smoking since 2000, even among the young. Smoking was previously associated with a certain status, but today smoking gives little status and respect among young people (NOVA, 2015).
Alcohol use is increasing in line with education and income levels. However, the proportion of people who are alcohol dependent is not highest among those with the highest socioeconomic status, but is highest among people with lower income and education (NIPH, 2009; Norwegian Directorate of Health, 2016).
Adolescents from families with low socioeconomic status (parents with short education and parents outside the labour market) are at more risk of earlier debut with alcohol, more frequent drinking and are intoxicated more often than their peers (Pape, 2017).
Obesity is less common among 40-year-olds with higher education than among 40-year-olds with lower education (Meyer, 2005). Social differences in overweight and obesity are also found among children (Biehl, 2013). However, the pattern is different in rich and poor countries. In a large study of 70 countries, it was shown that in poor countries there is more obesity among those with higher education, while in rich countries there is more obesity among people with lower education (Kinge, 2015b)
Smoking-related diseases explain much of the differences
To explain social inequalities in health, mortality and life expectancy, we have to look at both disease patterns and lifestyle habits.
Around 2000, significantly more died prematurely from heart attacks in the groups with lower education than in the groups with higher education. Here, premature death refers to death before 75 years of age. Calculations for all causes of death combined show that cardiovascular diseases explained about half of the differences between educational groups in terms of premature death (Strand, 2010). After 2000, the differences in mortality from cardiovascular diseases were significantly reduced (Strand, 2014), especially among men, see Figure 5a men.
Among women, there has also been a decline in educational differences in mortality from cardiovascular diseases, see Figure 5b women. However, parallel with this decline there has been an increase in educational differences in terms of mortality from lung cancer and COPD. Overall, therefore, the social inequalities in mortality among women has increased in the period from 2000 to 2009 (Strand, 2014).
Figure 5a. Differences in premature death among men with low and high education. Differences are shown for seven causes and in five periods. The diagram applies to the age group 45-74 years (premature deaths), the number of deaths per 100 000 per year.
Mortality rates are age-adjusted. The overall height of the columns represents the absolute difference in overall mortality. The figure is based on Figure 1 in (Strand, 2014).
Comments to Figure 5a:
We see that the total difference between educational groups was highest in the 1990s. We also see that there are various diseases that create differences (see colour codes). In the 1960s there was no apparent major cause. In subsequent decades, mortality from cardiovascular diseases created ever greater differences between educational groups. In the 2000s, the differences in mortality from cardiovascular diseases were still significant but less than in the previous decade.
Figure 5b. The difference in mortality between women who have low and high education. Differences are shown for seven causes and in five periods.
The diagram applies to the age group 45-74 years (premature deaths) during the period 1961-2009, the number of deaths per 100 000 per year. Mortality rates are age-adjusted. The total height of the columns represents absolute difference in overall mortality.
The figure is based on Figure 1 in (Strand, 2014).
Comments to Figure 5b:
We see that the total difference between educational groups is highest in the 2000s. We also see that there are various diseases that create differences (see colour codes).
In all decades, mortality from cardiovascular diseases creates large differences between educational groups. In the 2000s, the significance of cardiovascular diseases has been somewhat reduced.
However, the significance of lung cancer and COPD has increased.
Heart disease, COPD and lung cancer are all smoking-related diseases. Different smoking habits in groups with lower and higher education are probably a particularly important cause of social inequalities in mortality in Norway (Mackenbach, 2008; Mackenbach, 2016; Strand, 2010; Strand, 2014). Women and men with a long education first began to quit smoking, and the decline in mortality began therefore in these groups. Eventually, as the groups with short education change their smoking habits, we expect that they will also have a positive development and that the gap between the groups with medium and long education will become smaller. An important public health challenge is to combat smoking, especially in groups with lower education.
Differences between municipalities and counties mirror socioeconomic differences
80 per cent of the geographical variation in mortality between Norwegian men can be explained by various socioeconomic factors according to a large study of all deaths among 60-89 year olds in the period 2000-2008 (Kravdal, 2015). Among women, this is 73 per cent.
A similar study analysed differences between Norwegian municipalities in terms of obesity among young people (Kinge, 2015b).
The results show that about half of the variation in obesity among the municipalities could be attributed to socioeconomic conditions. The analysis was based on weight and height for nearly 200 000 young people at 17 years of age in the period from 2011 to 2013. In addition, data included socioeconomic conditions in the municipalities, such as income, the proportion with higher education and the proportion who were employed in managerial positions.
Geographical differences in life expectancy
Major inequalities exist between municipalities, districts and counties in terms of life expectancy. Similar differences can be found in other western societies (Sund, 2009).
- Life expectancy is highest in Akershus and Vestlandet lowest in Finnmark.
- There is a difference in life expectancy of up to 10–12 years between men living in the municipalities with the highest and lowest life expectancies, respectively. For women, the corresponding difference is up to 8–10 years.
- Within Oslo, the difference between districts is up to 8 years for men. For women this is 5 years.
- In Bergen and Stavanger, the corresponding differences between districts are 3 to 4 years. In Trondheim, the difference between the neighbourhoods is under one year.
Social inequality in the use of health services
Previous studies indicate that there are no significant social inequalities in the use of public health services and hospitalisations, while there is more use of private practitioners, dentists and public specialist clinics among groups with high socioeconomic status (Directorate of Health, 2009; University of Oslo, 2013).
However, recent analyses of data from Statistics Norway's living conditions survey in 2015 show that (Statistics Norway, 2017b):
- There was little difference by income in use of different services in groups with good health, while there was a clear social gradient in service use for groups with less good health, especially among the elderly. The differences were not as clear among the younger groups.
- The use of health care was higher among people with short education compared with groups with longer education. This was especially the case for services such as general practitioners and hospital admissions.
- Groups with longer education were more likely to have consulted a physician and dentist.
- In groups with less than good health, there were fewer differences between the education groups for most of the services.
It has been shown that cancer patients with long education and high incomes generally have better survival for the most common forms of cancer compared to patients with shorter education and low income (Kravdal, 2014; Skyrud, 2016). The reasons for this are not known, but it has been found that groups with low socioeconomic status to a lesser extent than groups with high status receive intensive treatment, such as surgery (Nilssen, 2016).
In recent studies, it has also been shown that there is better treatment and better health outcomes among cardiac patients with long education compared to heart patients (Sulo, 2016a; Sulo, 2016b). Treatment differences for dying patients have also been found (Elstad, 2018).
Norway in an international perspective
In Norway, the differences in mortality between educational groups are large. The differences are among the largest in Europe (Mackenbach, 2016). This has surprised both researchers and politicians.
New European figures suggest that mortality is falling and that life expectancy is increasing in all education groups. The countries that have had the strongest equalisation in recent years are Spain, Scotland, England / Wales and Italy (Mackenbach, 2016). Since 2005, the decline in mortality was greatest among those with the lowest education, especially for men. This is a positive development.
The levelling out between educational groups in European countries is mainly due to fewer people dying from heart attacks and other smoking-related diseases. Lifestyle changes and treatment for high blood pressure and high cholesterol have been important contributing factors. Better medical care and higher survival rates from heart attacks have also been significant (Mackenbach, 2016).
In a comparison between 22 European countries, Norway is the country with the largest difference between educational groups for the proportion of daily smokers. The proportion of daily smokers was approximately four times higher among those with lower secondary education than among those with higher education (Mackenbach, 2008).
Health and social conditions inter-related
Health and lifestyle habits such as smoking, diet and physical activity are closely linked to social conditions, local communities, housing and living conditions (Dahl, 2014). Some causal relationships are probably influential throughout life (Blane, 2013) and the interaction between factors is important.
Basically, all conditions that affect public health and which are unevenly spread will help to create and sustain social inequalities in health.
To even out any health differences, one can begin with the underlying factors.
- Basic social conditions affect the entire causal chain
- Lifestyle, social support and other physical and social environmental factors directly affect health.
- Health services can counteract inequalities created earlier in the causal chain. Employment and adaptive education can also help to alleviate inequalities.
Lifestyle habits are primarily a result of the environment and living conditions. Factors such as economy, education, and living and working conditions may therefore affect health and the risk of disease, both in a positive and negative way.
Facts about noise
Noise is an example of an environmental factor that affects health in various ways. A report published by Statistics Norway shows that children and adolescents (0-20 years) in families with lower education increasingly live in areas with high noise levels (Statistics Norway, 2012).
- About 20 per cent of children in households with secondary education as their highest education were exposed to noise problems. The corresponding figure for children in families with higher education was 8 per cent.
- In low-income families, 14 per cent of children lived in houses with noise problems compared to 9 per cent in families with the highest incomes.
Noise can affect behaviour, lead to sleep disturbances, reduce the possibility for concentration and learning, as well as causing stress disorders. Such reactions to noise can have a huge impact on well-being, relaxation and health (WHO, 2011). Road traffic is the major source of noise in the community, followed by railways.
Great opportunities to improve public health
Efforts to improve living conditions, such as employment, education and living environment can help to promote health. This will also reduce social inequalities in health and increase life expectancy in all groups. The large differences in health and lifestyle habits that we see in Norway are a social problem that can be changed (Dahl, 2014).
Reduced social inequalities in health is also an important goal in health promotion. Levelling of social inequalities in health has a great potential for improvement of public health.
The Norwegian version of this article is an update of the chapter about Social Inequalities of Health in the Public Health Report 2014. Translated to English in March 2017, updated in 2018.
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