Review: Emotional and behavioral functioning in phenylketonuria

Abstract

Objective: To examine 17 studies of the psychological sequelae of early- treated phenylketonuria (PKU) with emphasis on the impact of dietary control on functioning. Two questions are addressed: (1) What is the typical psychological profile associated with PKU? (2) Is emotional and behavioral disturbance more prevalent in PKU-affected individuals compared to appropriate controls? Method: Computerized searches of PsycINFO® identified studies using behavioral, personality, and diagnostic measures. Results: Findings converge upon a profile including attentional difficulties, depression, anxiety, and low self-esteem. Methodological constraints limit conclusions regarding the nature and severity of observed difficulties. A single study has used comparison groups appropriate for the simultaneous examination of the questions posed (Waisbren and Levy, 1991). Conclusions: We discuss results using a biopsychosocial framework, addressing the factors and processes that may influence emotional and behavioral functioning in this neurodevelopmental disorder. We outline potential lines of new investigation that address critical methodological factors.