What is burden of disease?
In short, it’s a set of statistical techniques we use to measure the impact on a population of diseases, health conditions, injuries and various health risk factors.
The impact is not in terms of money or health treatment costs it’s in terms of years of life lived in ill health or with a disease or injury, as well as years of life lost due to dying
early from a disease. So, overall, with Burden of Disease analysis we are basically measuring a health gap. This gap is the difference between the actual health of a population and the ideal situation where everyone lives a long life in full health. At the moment, from looking at the lowest death rates from around the world, we have set the ideal life span for both men and women at birth at 86 years.
And with the years lived in ill health, we recognise that some diseases are more debilitating or more severe than others, so we have special disability weights for each disease that take account of this. You will hear acronyms mentioned in relation to burden of disease. For example, the years of life lived in ill
health are called YLDs, years lived with disability… or the non-fatal burden.
The years of healthy life lost due to early death are called YLLs, which stand for years of life lost… also known as the fatal burden. When you add the two types of lost years together that is the YLDs and the YLLs together they are called DALYs, or disability-adjusted life years. Diseases vary in whether their overall burden is mostly due to living in ill health or due to early deaths.
For example the highest burdens in terms of early deaths are due to cancer, cardiovascular disease and injury. But in terms of burden from living with a
disease, mental and substance use disorders and musculoskeletal conditions score the highest. Another important part of our study is that we have been able to estimate what is called the attributable burden. This is the health loss attributable to health risk factors such as smoking, alcohol use, being overweight and lack of exercise.
We have also been able to quantify the negative effects of these health risks.