People living in more deprived areas have a higher risk of death after heart surgery, experts have found. Dr. Domenico Pagano, of Queen Elizabeth Hospital, Birmingham, UK, and colleagues carried out a recent study into modifiable risk factors for death after cardiac surgery.
On the website of the British Medical Journal, they explain that social inequalities are known to increase overall mortality. “The link between poverty, socioeconomic inequalities, and increased mortality is well established,” they write, “but the extent to which such inequalities can be modified is unknown.”
They carried out the study because cardiovascular disease is the top cause of premature death in the Western world, and is also “closely related to socioeconomic deprivation.” Heart surgery encompasses many beneficial procedures, and the team investigated whether the benefits apply across all socioeconomic levels.
They analyzed figures on 44,902 adults undergoing cardiac surgery between January 1997 and December 2007. Social deprivation scores were derived from levels of unemployment, car ownership, overcrowding, and low occupational social class in the patient’s neighborhood.
Social deprivation was significantly linked to risk of death in hospital. Surviving patients were followed for approximately five years, during which 12 percent died. Again, social deprivation was linked to reduced long-term survival.
The extra risk was partly accounted for by smoking, body mass index, and diabetes. But when these were taken into account, deprivation remained a strong predictor of increased risk. The researchers say this suggests that some other factors related to deprivation are having a negative effect on survival.
The team writes, “In summary, people from deprived socioeconomic groups not only have a shorter life expectancy but also spend a greater proportion of their lives affected by disability or illness. We have identified some important modifiable clinical factors (smoking, body mass index and diabetes) that if addressed might substantially reduce the adverse effects of social deprivation on survival after cardiac surgery.”
However, they add, “The influence of social deprivation on survival remained predictive, indicating that some additional factors related to deprivation might influence outcome.” They believe that the risk could be lowered by better targeting of resources and education on how to engage with healthcare services.
Commenting on the study, Dr. Martin Denvir and Dr. Vipin Zamvar of the Royal Infirmary of Edinburgh, UK, state, “The difference in risk between affluent and deprived patients is striking.”
They suggest that by 65 years of age (the median age of patients in the study) home location is probably determined by several factors, including educational achievement, employment status, and economic security, all of which will have been influencing health status throughout life. “Patients with social deprivation are therefore more likely to have severe disease and other comorbidities at the time of surgery,” they write.
“The overarching marker of social deprivation is poverty,” they add. “Poverty can cause social, familial, cultural, educational, environmental, emotional, and aspirational problems. Narrowing the gap between the health of the rich and the poor can be achieved only by dealing with the root causes early on in life and continuously throughout life. A good start in life – including decent education, adequate housing, and adequate employment opportunities – is most important. Health will follow.”
Dr. Johan P Mackenbach of Erasmus University in Rotterdam, The Netherlands, gives his opinion on social inequalities in death rates. He writes, “Advocates of psychosocial explanations of health inequalities argue that relative material disadvantage is likely to be more important for the explanation of health inequalities than absolute disadvantage, because health inequalities are found in rich countries as well as in poorer countries, and there is little relation between average income and life expectancy in richer countries.”
Dr. Richard G Wilkinson, of the University of Sussex, UK, agrees. He says that mortality is related more closely to relative income than to differences in absolute income. National mortality rates tend to be lowest in countries that have smaller income differences and thus lower levels of relative deprivation, he points out, adding that most of the rise in life expectancy seems unrelated to economic growth rates.
In his opinion, health can be affected by perceptions of our place in the social hierarchy, based on income. If this perception is poor, it causes negative emotions such as shame and distrust that are translated “inside” the body into poorer health.
Dr. Wilkinson concludes, “Social dominance, inequality, autonomy, and the quality of social relations have an impact on psychosocial wellbeing and are among the most powerful explanations for the pattern of population health in rich countries.”
But his argument has not been widely accepted. Some researchers say the association depends on which countries are included in the analysis, and a further study found that absolute income is a better predictor of subjective health than relative income, and concluded that “exposure to others who are better off will not automatically influence one’s moods in a negative way.” The role of psychological factors in health inequalities remains to be clearly understood.
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