Medical, cognitive and affective status of four-year-old very premature babies without severe disability. A case-control study

To determine cognitive performances and affective development of a cohort of very premature babies at the age of 4 years. Longitudinal case-control study. Newborns less than 33 weeks gestation were included from 1992 to 1994 and were matched with two full-term newborns. At 4 years of age, they have been evaluated for medical status, cognitive functions with the K-ABC test and affective condition with the PSA and Conners' tests. The preterm group was significantly different from the controls for: a smaller height, (P < 0.01), a lower socioeconomic level (P = 0.027), a lower nursery school level (44% versus 27,6%, P = 0.05), the incapacity to draw "a bonhomme" (55,3% versus 93%, P < 0.001), lower performances for the K-ABC and PSA tests, a pathologic Conners score (20.4% versus 2.4%, P < 0.001). Multivariate analysis by logistic regression showed a similar neuropsychological results: a lower score of K-ABC (< 80, P = 0.0006, odds-ratio = 33.2), and a lower social competence score of PSA (< 45, P = 0.004, odds-ratio = 35.9). Follow-up of premature babies is required, and measures to prevent or minimize cognitive and social disabilities are mandatory.