ESPE Abstracts

Background: Recombinant human growth hormone (rhGH) therapy is a long-term injection treatment that can be burdened by poor adherence. Although adherence rates are usually good in childhood, children and adolescents can be particularly stressed by daily injections, resulting in a low quality of life (QoL).

Objectives: To assess the degree of adherence and stress related to daily rhGH treatment based on data reported by patients and caregivers. To evaluate factors influencing adherence to rhGH and therapy-related stress.

Methods: Patients on rhGH treatment for at least one year were recruited during their six-month follow-up. Patients treated due to isolated GH deficiency (GHD) or small for gestational age (SGA) were included. A questionnaire was administered to patients and/or caregivers (for children < 6 years). Adherence was defined ‘good’ (one missed dose per week) or ‘moderate/poor’ (>1 missed dose per week). The questionnaire included questions on parents' education, employment, family residence, household composition, rhGH therapy duration, who gives the injections, perception of therapy's effectiveness, agophobia, chronic therapy-related stress, discomfort towards peers related to chronic treatment, problems transporting vials.

Results: Seventy patients were recruited (60% male, 40% female; mean age 11.7±2.86 years); 77.1% were pubertal and 22.9% prepubertal. 68.6% were treated for GHD while 31.4% because of SGA. Therapy mean duration was 56.2±34.6 months. The questionnaire was completed in 60% of the cases by the patient while in 40% by the parent. Adherence was good or medium/poor in 82.9% and 17% of cases, respectively. Therapy was administered by the parent or by the patient in 77.1% and 22.9% of cases, respectively. rhGH was perceived as useful in 77.1% of cases, while as unhelpful or imposed by parents or doctor in 22.9%. Agophobia was reported in 25.7% of the cases and discomfort towards peers related to chronic treatment in 22.9% of cases. Therapy-related stress was declared in 41.4% of cases. At the univariate regression analysis therapy-related stress was significantly influenced by agophobia (OR 2.9, 95%CI 1.05-8.97; P = 0.045) and discomfort towards peers (OR 4.4, 95%CI 1.32-14.59; P = 0.015). These results were confirmed at multivariate regression analysis adjusted for sex, age, pubertal stage (P <0.05). No factors significantly influenced adherence to therapy.

Conclusion: Agophobia and discomfort towards peers related to chronic treatment are associated to therapy-related stress in childhood, despite a high degree of adherence. These factors should be identified early to plan strategies to mitigate their negative effects on the QoL of children and adolescents treated with rhGH.