Years of life lost due to Huntington disease.

Many genetic diseases shorten the lives of people who have them. Hence, it makes sense to speak of years of life lost due to cystic fibrosis or sickle-cell anemia or numerous other genetic disorders. In conventional practice, years of life lost is calculated for causes of death only, but a genetic disease is better understood as a risk-altering state or condition: it acts not at the time of death only but from birth onwards. Therefore, we must reformulate the concept of years of life lost before applying it to genetic conditions. This has already been done for congenital genetic diseases. This paper extends the reformulation to diseases with delayed onset. Huntington disease (HD) is used as an example.