Increased life expectancy does not lead to more healthy years

According to data from 1990 to 2023, the gap between overall life expectancy and healthy life expectancy, known as the “illness gap,” has increased in almost all countries and territories analyzed. Over one generation, this gap has grown by almost two years, from 8.8 years in 1990 to 10.7 years in 2023. On average, people spent 14.5% of their lives in poor health in 2023, which is higher than the 13.6% in 1990. Moreover, the deterioration was not limited to the last years of life. Instead, it extended throughout the adult years, indicating that people are increasingly living with chronic diseases and disabilities for a significant portion of their adult lives.

Over the same period, global life expectancy at birth increased from 64.6 to 73.8 years, while healthy life expectancy increased from 55.9 to 63.1 years. As overall survival rates consistently outpaced healthy life expectancy, people were spending more time with chronic diseases and functional limitations. Even the COVID-19 pandemic, which temporarily affected life expectancy and healthy life expectancy, did not change the overall trend.

The gap between “years of life” and “years of health” is particularly large in high-income countries. In 2023, the United States had the largest national gap, at 14 years, followed by Australia (13.9 years) and Canada (13.7 years). In general, regions with higher socio-demographic development indices (SDI) have longer life expectancy, but also spend more years in poor health. This reflects the fact that improvements in life expectancy are not accompanied by a corresponding increase in healthy life expectancy. In all seven GBD superregions, both the absolute number of years and the proportion of life spent in poor health increased between 1990 and 2023. In the high-income group, this gap was 12.7 years in 2023, while in sub-Saharan Africa, it was 9.0 years.

In all regions and at all levels of socioeconomic development, women live longer than men but spend more years in poor health. In 2023, the average gap in morbidity between women and men was 12.1 years and 9.3 years, respectively. This pattern is evident in all indicators of the SDI index, where women generally live longer, but these additional years are often associated with illnesses and disabilities.

More than half of the world’s years spent in poor health are attributed to a relatively small group of predominantly non-fatal chronic conditions, accounting for 57.4% of unhealthy years in 2023. The largest contributors to the gap are musculoskeletal diseases, particularly low back pain. This is followed by mental disorders (such as depression and anxiety), sensory disorders (including age-related hearing loss), falls and other unintentional injuries, and other chronic non-communicable diseases.

A significant portion of these years is associated with risk factors that can be prevented or controlled. Globally, the main risk factors are high fasting glucose levels, high body mass index, inadequate nutrition in children and mothers, and tobacco use. However, the picture varies significantly by region: in sub-Saharan Africa and other regions with low SDI, malnutrition among children and mothers remains a leading factor. Air pollution is also among the top five key factors.

According to Dr. Christopher Murray, director of the Institute for Health Metrics and Evaluation (IHME) at the University of Washington School of Medicine and a senior author of the study, further progress in public health should focus not only on increasing life expectancy but also on improving healthy life expectancy. This requires more investment in prevention, long-term management of chronic diseases, and the care system.

As Katherine Bisignano, IHME’s senior science editor and co-author of the paper, points out, improving healthy aging requires addressing the conditions and risk factors that contribute to disability. By addressing these factors early on, such as through prevention and improving the long-term care system, significant impacts on society, healthcare, and the economy can be achieved.