People are living much longer worldwide than they were two decades ago, as death rates from infectious diseases and cardiovascular disease have fallen, according to a new, first-ever journal publication of country-specific cause-of-death data for 188 countries. Published in The Lancet on December 18, the study, "Global, regional, and national age-sex-specific all-cause and cause-specific mortality for 240 causes of death, 1990-2013: a systematic analysis for the Global Burden of Disease Study 2013," was conducted by an international consortium of more than 700 researchers led by the Institute for Health Metrics and Evaluation (IHME) at the University of Washington.
As per study, given the size of India's population in particular, and projections that it may soon become the world's most populous country, mortality trends there have global implications. In 2013, India accounted for 19 percent, or 10.2 million, of the world's deaths. The country has made great strides in reducing both child and adult mortality since 1990. The average yearly rates of decline in mortality have been 3.7% per year for children and 1.3% per year for adults. Between 1990 and 2013, life expectancy at birth increased from 57.3 years to 64.2 years for males and from 58.2 years to 68.5 years for females.
"It's very encouraging that adults and children in India are living longer and healthier lives," said Dr Jeemon Panniyammakal of the Public Health Foundation of India and a co-author of the study. "But India's growing influence on global health means we must do more to address the diseases that kill people prematurely."
Compared to previous Global Burden of Disease (GBD) studies, researchers from more than 100 nations incorporated more country-level data as well as additional data on specific conditions. They also examined whether leading causes of death in lower-income countries are beginning to mirror those in higher-income countries. What they found is that even with big improvements in longevity in low-income countries, the types of health challenges faced by countries such as Bolivia, Nepal, and Niger are far different from those faced by countries such as the Japan, Spain, and the United States. The health challenges of many middle-income countries such as China or Brazil are also closer to those in the US.
Causes of death vary widely by country, but, at the global level, drug use disorders and chronic kidney disease account for some of the largest percent increases in premature deaths since 1990. Death rates from some cancers, including pancreatic cancer and kidney cancer, also increased. At the same time, countries have made great strides in reducing mortality from diseases such as measles and diarrhea, with 83 percent and 51 percent reductions, respectively, from 1990 to 2013. Globally, three conditions - ischemic heart disease, stroke, and chronic obstructive pulmonary disease (COPD) - claimed the most lives in 2013, accounting for nearly 32% of all deaths.
The average age of death increased from 46.7 in 1990 to 59.3 in 2013, as a result of declining fertility and a demographic shift in the world's population to older ages. Partly because of global population growth, the number of deaths in both sexes for all ages combined increased from 47.5 million to 54.9 million.