A prevalence estimate of pervasive developmental disorder among immigrants to Israel and Israeli natives - A file review study

Background. The prevalence rates of pervasive developmental disorder (PDD) have risen in the West over the last 10 years. There is argument over the etiology of this change in rates. Social and cultural processes including migration have been hypothesized. Israel, as a country of ongoing immigration with a national registry of children diagnosed with PDD, offers an opportunity to compare rates of PDD among immigrants from developing countries and native Israelis. Method. A Social Security national registry of 1,004 children diagnosed with PDD was reviewed and rates were calculated using data extracted from the Israel National Bureau of Statistics. Of all Jewish children that were born in the years 1983-1997 and who are currently living in Israel, we defined four groups: (1) native Israelis of non-Ethiopian extraction (N = 1,198, 300), (2) native Israelis of Ethiopian extraction (N = 15,600), (3) immigrants of non-Ethiopian extraction (N = 110,300) and (4) children born in Ethiopia (N = 11,800). A further breakdown of groups 1 and 3 by well-characterized ethnic or geographical origins was not possible. Results. The rate of PDD was significantly elevated in native Israelis as compared to all immigrant children. Among immigrants, the rate of PDD in Ethiopian-born children was lower than that of those born in other countries. The rate of PDD in immigrant Ethiopian children was much lower than in native Israeli children of Ethiopian extraction. Conclusions. Birth in Israel, an industrialized country, is a marker for an environmental risk factor for PDD. This may indicate that gestation, birth or infancy in industrialized countries exposes children to environmental insults that increase the risk for contracting PDD.