From the desk of: Mirko Hennig, Ph.D.
“Wishing you a long, happy and healthy life” is what we repeatedly say as we get older. A recent, global study published in The Lancet (2015; 386, p.743-800) clearly emphasizes the importance of the latter referring to our quality of life. According to the Global Burden of Disease (GBD) study, worldwide life expectancy at birth rose by 6.2 years between 1990 and 2013. However, these additional years come at a price as healthy life expectancy at birth increased by only 5.4 years over the same 13 year time span. The massive, country-specific assessment utilized age-specific mortalities and data accumulated for 306 diseases in 188 countries between 1990 and 2013. While the study highlights the need for more and better data about disabilities to estimate healthy life expectancies in a more reliable manner, several consistent trends emerge:
Implications of this study
Living longer but suffering more? While life expectancy in 1990 in the US averaged 71.9 and 78.8 years for male and female population, respectively, it increased significantly reaching averages of 76.3 and 81.4 years in 2013. However, the years of life expectancy gained are not necessarily lived healthily. On average, 9.2 (8% of life expectancy) and 11.9 (15%) years of male and female lives born in 1990 are associated with disability. This burden of disease increases to 10.5 (14%) and 12.8 (16%) years for male and female population born in 2013. Thus, the data suggests a widening gap between longer and healthy lives.
Neglected, age-related diseases. The reason for an increased disease burden over our longer life spans can at least partially be attributed to a rising prevalence of age-related conditions. While the GBD team shows that health loss due to cardiovascular and circulatory diseases and cancer stagnated or even decreased over the period 1990-2013, the drivers of the difference between longer and healthy life expectancies are musculoskeletal disorders, mental and substance use disorders, neurological disorders, and diabetes, accompanied by vision and hearing loss.
While the leading cause of increased disease burden in the US in 2013 continues to be ischemic heart disease, it is now followed by back and neck pain. Chronic obstructive pulmonary disease ranks third. Tracheal, bronchus and lung cancer, depression, diabetes, Alzheimer’s, other musculoskeletal disorders, stroke and sense organ disorder round out the 2013 top ten in the US.
Take-home message
Research and development investments by the National Institutes of Health (NIH) and the pharmaceutical industries have traditionally focused on cardiovascular diseases, endocrine disorders and cancer. As a consequence, sustained gains have been made against the majority of the leading causes of death worldwide. On the other hand, few age-related diseases such as musculoskeletal disorders, neurological disorders, diabetes and hearing and vision loss receive the attention they deserve in public policy discussions and health research priorities. A balanced diet rich in antioxidants and anti-inflammatories plays an important role to forestall the onset of age-related disorders. Therefore, researchers at the Nutrition research Institute (NRI) in Kannapolis including Drs. Cheatham, Surzenko and Zeisel investigate the interplay of nutrition and cognitive function. However, more investment and research has to shift towards diseases that debilitate, rather than kill in order to maintain health progress in ageing populations.
