Objective: To evaluate the self-reported prevalence of poor adherence to recombinant human growth hormone (rhGH) therapy in a large, representative sample of Italian children and adolescents and to assess treatment and patient level correlates of poor adherence.
Methods: The study was conducted in 46 pediatric centers throughout Italy. A questionnaire was administered to consecutive children/adolescents treated with rhGH or their parents. Eligible patients were represented by subjects aged between 6 and 16 years, of both sexes, on rhGH treatment for at least 6 months. The questionnaire was administered to the person in charge of preparing the injection. Multivariable logistic regression analysis was performed to identify factors independently associated with adherence.
Results: Overall, 1,007 children/adolescents were involved, of whom 24.4% missed 1 or more injections during a typical week and were thus considered as nonadherent. The most frequently reported reasons for missing a dose were being away from home (33.3%), forgetfulness (24.7%), not feeling well (12.9%), and pain (10.3%). Multivariable analysis indicated association between poor adherence and adolescence, low level of parent education, longer duration of treatment, need to convince the child to inject, and low level of awareness of the consequences of not properly following treatment. The likelihood of adherence markedly increased with higher levels of perceived device convenience.
Conclusion: Poor adherence is still a major problem in the treatment of growth disorders. Increasing awareness and reassessment of treatment adherence on an annual basis should be part of clinical practice of pediatric endocrinologists involved with rhGH treatment.
Abbreviations: CI = confidence interval GH = growth hormone rhGH = recombinant human growth hormone.