Background: GH treatment requires regular, daily s.c. injections for very long periods of time when not virtually for a lifelong period. The mean final height attained with GH therapy is influenced by poor adherence to treatment.
Objective and hypotheses: The main aim of this study was to identify non-adherent patients to GH therapy and to determine the influence of compliance in response to the treatment (IGF1 serum levels and growth velocity). We also evaluated the influence of socioeconomic factors on the therapeutic adherence.
Method: 165 children treated with rhGH were included. Age, gender, etiology, Tanner state, duration of treatment, growth rate, IGF1 serum values, daily dose and annual dose data were collected. The prescribed dose and the dose administered by the hospital pharmacy were compared. Poor adherence was defined as a rate below 92% of prescribed dosage. A subgroup of 106 patients (53 poor-adherent patients and 53 good-adherent ones) was asked to answer a questionnaire to assess social and environmental factors.
Results: 34% of the patients showed moderatelow adherence to rhGH treatment. There was a decrease in adherence associated with age (P<0.04) and treatment duration (P<0.001), but no differences were found in relation to GH deficiency diagnosis. The median HV-SDS (height velocity SDS) in patients who showed good adherence to therapy was higher (1.29 vs 0.47) when compared to the group of poor adherence (P<0.001). Adherence was significantly related to IGF1 (1.3 vs 0.4; P<0.001) and with the level of education of the mother (P<0.007).
Conclusion: One-third of our patients presented poor adherence to GH therapy, which results in suboptimal growth. IGF1 levels could be helpful to identify patients with lower adherence. Physicians should pay special attention to certain characteristics of the patient and their environment to encourage desirable therapeutic compliance.
20 - 22 Sep 2014
European Society for Paediatric Endocrinology