A national study of physician recommendations to initiate and discontinue growth hormone for short stature.

OBJECTIVES: Overall growth hormone (GH) use depends on decisions to both initiate treatment and continue treatment. The determinants of both are unclear. We studied how physicians decided to begin GH in idiopathic short stature and how, after an initial course of treatment, they decided to continue, intensify (increase the dose), or terminate treatment.
METHODS: We used a national census study of 727 pediatric endocrinologists involving a structured questionnaires with a factorial experimental design. Main outcome measures were GH recommendations for previously untreated children and those children who were treated with GH for 1 year.
RESULTS: The response rate was 90%. In previously untreated children, recommendations to initiate GH were consistent with guidelines and also influenced by family preferences and physician attitudes (P<.001). In children treated with GH, recommendations on whether to continue GH were influenced by the growth response to therapy (P<.01) but were divided regarding course of action. With identical growth responses to treatment, physician decisions diverged (intensify versus discontinue GH) and were driven by independent, nonphysiologic, and contextual factors (eg, physician attitudes, family preferences, and GH-initiation recommendation; each P<.001). Together, attitudinal and contextual factors exerted more influence on continuation decisions than did the growth response to therapy.
CONCLUSIONS: Physician decisions to initiate GH are largely consistent with evidence-based medicine. However, decisions about continuing GH vary and are strongly influenced by factors other than response to treatment. With a potential market of 500 000 US children and costs exceeding $10 billion per year, changes in GH use may depend on potentially modifiable physician attitudes and family preferences as much as physiologic evidence.