Importance For the past 100 years, medicine in industrialized nations has become increasingly focused on specific medical interventions designed to improve the health of individual patients. Substantial evidence suggests that broader improvements in public health, nutrition, and economic well-being are more salient than medical or surgical interventions for the remarkable decrease in infant and child deaths since 1900. Less is known about the impact of specific medical interventions on morbidity such as intellectual disability (ID).
Objective To explore the impact of medical interventions in early childhood on increasing the prevalence of later ID, as reported in the literature from 1950 through 2000.
Design We reviewed the medical literature and other data from 1950 through 2000 to construct estimates of the condition-specific prevalence of ID over time. We further explored the existing literature to document historically relevant influences on condition-specific prevalence, including the introduction of effective interventions, the timing of these introductions, and the likelihood of their widespread use.
Setting Twentieth century United States and Western Europe.
Participants Populations of children who received a life-saving intervention within the first 5 years of life and were evaluated for ID after 5 years of age.
Main Outcome Measures Case-specific prevalence of ID from 1950 through 2000.
Results Low birth weight is associated with approximately 10% to 15% of the total prevalence of ID. No other new medical therapies introduced during this period were associated with a clinically significant increase in ID prevalence.
Conclusions and Relevance Previous research has shown that specific medical interventions, such as newborn screening for congenital thyroid deficiency and phenylketonuria, have decreased the prevalence of ID approximately 16% in the United States since 1950. These results suggest that other medical interventions, particularly the advent of intensive care technologies, have also increased the prevalence of ID.