Unmasking Adherence as a Cause of Unexplained Poor Growth Response in Adolescents Receiving Growth Hormone

Abstract

Purpose: To evaluate whether a digital record of injections can reveal nonadherence as the cause of unexplained poor growth response in adolescents on growth hormone therapy. Methods: Twelve adolescent patients receiving growth hormone (GH) treatment who developed unexplained poor growth for six months were identified. Patients were transitioned to a digital record of GH administration (easypod™) from their original method of administration. Growth rates and IGF-I levels prior to and after 3 months of digital monitoring were compared. Results: Mean age of the 12 participants was 15.6 ±1.9 years and mean duration of GH therapy was 4.5 ±2.7 years. Only one patient acknowledged poor adherence prior to starting easypod, but injection history log showed that five of the patients initially were not adherent with the daily injections. Four of these five patients then became adherent. Four patients were noted to be adherent at the initiation of easypod therapy but nonadherence could be suggested by their improved growth rates on easypod therapy. Mean growth rate of all subjects increased from 2.5 ±2.5cm per year compared to 6.3 ±3.8cm per year after transition to easypod (P<0.01). One patient remained poorly adherent for the duration of the study and two of the twelve patients remained poorly growing even though proven to be adherent to GH therapy by the digital injection record. These 3 patients discontinued GH therapy. There was no significant change in serum IGF-I levels before and after easypod use (P=0.25). Conclusion: A digital record of injections is useful in revealing nonadherence as the cause of unexplained poor growth response in adolescent