Patient age distribution in thalassemia major: changes from 1973 to 1985.

Major advances have occurred in the treatment and prevention of thalassemia major, but their impact on incidence and survival have not been well assessed. In 1973, a survey was done of the ages of 243 living patients with thalassemia major followed at 12 centers in the United States and Canada. Twenty-two percent were younger than 5 years and 2.1% were older than 25 years of age (mean 11.4 +/- 6.7 [SD] years). In 1985, there were 303 patients at the same centers; 11% were younger than 5 years and 7.9% were older than 25 years (mean 14.2 +/- 7.3 years). A similar pattern was found in Connecticut, characterized by a marked decrease of new cases of thalassemia major during the past 15 years. This was not a result of fewer persons at genetic risk or a change in marital ethnic choices. Eleven of 14 families who had a child with thalassemia major assured that another affected child would not be born by having no more children, using prenatal diagnosis, or having therapeutic abortions. Extensive community programs of education and testing for thalassemia trait in Connecticut may also have contributed to the observed reduction in new cases.