An international study has revealed that between 1980 and last year, global life expectancy increased from about 62 years to 72 years but the improvement was negated to some extent by increasing numbers of people suffering serious health threats related to obesity, high blood sugar, and alcohol and drug abuse.
This was among the findings in a range of papers co-authored by Epidemiologist at UKZN, Professor Benn Sartorius, and published in a dedicated issue of The Lancet as part of the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD).
The study draws on the work of more than 1 800 collaborators in nearly 130 countries and territories.
Many countries have shown improvements in life expectancy from fewer suicides in France to lower death rates on Nigerian roadways to a reduction in asthma-related deaths in Indonesia.
In South Africa, male life expectancy improved from 66.5 years in 1990 to 70.8 years in 2015, while for women it increased from 71.7 years in 1990 to 76.6 years in 2015.
Although the majority of deaths in the country are still caused by HIV and AIDS, the increase in life expectancy is due to the significant scale up of antiretroviral therapy preventative measures such as male circumcision, expansion of HIV testing as well as reduced HIV transmission from mother to child.
Globally, 5.8 million children under the age of five died in 2015, representing a 52% decline in the number of deaths in the age category since 1990. The rate also decreased considerably in South Africa from 1 693 deaths per 100 000 in 1990 to 772 in 2015.
The study also indicated that to a large extent, human health is determined by risk factors, some of which are within a person’s control.
Between 1990 and 2015, global exposure to unsafe sanitation, household air pollution, being underweight during childhood, childhood stunting, and smoking each fell more than 25%. However, exposure to several occupational risks, high body mass index, and drug use increased more than 25% in the same period.
In South Africa, the top 10 causes of premature deaths were HIV/AIDS, interpersonal violence, lower respiratory tract infection, road injuries, tuberculosis, ischemic heart disease, diabetes, cerebrovascular disease, diarrheal diseases and neonatal preterm births. The study found that factors driving the highest amount of death and disability in the country include: unsafe sex, high body mass-index, high fasting plasma glucose, dietary risks, alcohol and drug use, high systolic blood pressure, tobacco smoke, child and maternal malnutrition, air pollution and unsafe water, sanitation and hand washing.
Apart from HIV and AIDS, this is in line with the global findings where risk factors are exacerbated by poor diet, lack of exercise, and smoking, and lead to a significant health burden.
High systolic blood pressure was the top risk factor in 2015, contributing to over 9% of global health loss, followed by smoking (6.3%), high blood sugar (6.1%), and high body mass index (BMI) (5%).
According to the World Health Organization, diet has for many years played a key role as a risk factor for chronic lifestyle diseases.
Significant changes at global level have been observed since the 1950s, inducing major population level shifts in diet, first in industrial regions and more recently in developing countries. Traditional, largely plant-based diets have been swiftly replaced by high-fat, energy-dense diets with a substantial content of animal-based protein. However, diet, while critical to prevention, is just one risk factor. Physical inactivity, now recognised as an increasingly important determinant of health, is the result of a progressive shift of lifestyle towards more sedentary patterns, in developing countries as much as in industrialised ones.
Recent data from São Paulo in Brazil, for example, indicate that 70%-80% of the population are remarkably inactive. The combination of these and other risk factors, such as tobacco use, is likely to have an additive or even a multiplier effect, capable of accelerating the pace at which the chronic disease epidemic is emerging in the developing countries.
Commenting on the findings, Sartorius said: ‘Major gains have been made both globally and in South Africa. However, this progress is threatened by an increasing burden of obesity, high blood sugar (diabetes), high blood pressure (hypertension) and alcohol abuse.
‘Local policy makers need to tackle these important issues as South Africa further undergoes the epidemiology transition to increased non-communicable disease burden and particularly the potentially growing high risk population of HIV+ve individuals (with now increased longevity due to ART) who are more susceptible to certain non-communicable disease conditions. This will place an additional burden on our already taxed health care system.’