Mortality in achondroplasia study: a 42-year follow-up.

Achondroplasia (ACH) is the most common dwarfing condition having a prevalence of 1/25,000 live births. An increase in overall mortality, age specific mortality up to age 34 years and heart disease-related mortality was first reported in a 1987 study of a large population of ACH individuals. Since this study, concern about premature death, particularly in young adults, has persisted in the ACH population. The present study was undertaken to follow-up the patterns of mortality in a more contemporaneous ACH population. The vital status of 718 ACH individuals from the original study and 75 new ACH individuals was determined through the search of two computerized mortality database. The results showed that the overall mortality and age-specific mortality at all ages remained significantly increased. Rates of death were similar across all 42 years of follow-up suggesting that higher death rates were still occurring in the contemporary ACH population. Accidental, neurological, and heart disease-related deaths were increased in adults. Heart disease-related mortality, between ages 25 and 35, was more than 10 times higher than the general population. Overall survival and the average life expectancy for this ACH population were decreased by 10 years. These results demonstrate that despite advances in the knowledge of the natural history of ACH and health care needs of this population, mortality remains significantly increased. The high rate of heart disease related deaths illustrates the need to identify risk factors in the ACH population and develop treatment interventions accordingly.