SAT-281 Relationship between Socioeconomic Status, Adherence and Outcomes to Growth Hormone Treatment in Children: Real-World Treatment Patterns in Israel

Background: The goals of growth hormone treatment (GHT) during childhood and adolescence are to normalize height velocity and attain a final adult height within the normal range. Despite decades of use, little data is available on GHT patterns and outcomes in a real-life environment. Maccabi Health Services (MHS) is Israel's second biggest health maintenance organization and the database includes up to 20 years of data on 2 million members, offering a unique opportunity to follow real-life GHT children's demographics, clinical data and adherence to therapy. Objective: To assess a decade of GHT patterns and outcomes in a real-world setting via the MHS database. Methods: This was a retrospective cohort database study of all children initiating GHT in MHS (January 2004-December 2014) who met uniform criteria for diagnosis and initiation of therapy. Age, sex, socioeconomic status (SES) and auxologic parameters were recorded at initiation of therapy, and height gain standard deviation score (ΔHtSDS) was calculated during the study period. Adherence was evaluated using proportion of days covered (PDC). Results: 3325 children initiated GHT of whom 2379 were included in the study cohort (62.1% males). The two main indications observed were Idiopathic Short Stature (ISS; n=1615, 67.9%) and Growth Hormone Deficiency (GHD; n=611, 25.7%). Children belonging to the upper third of SES comprised 61.3% of ISS and 59.7% of GHD patients. At initiation of GHT, mean height-SDS was -2.36±0.65 (-2.36±0.6 for GHD and -2.30±0.67 for ISS, p=0.0417); mean age was 9.8±3.1 years (9.42±3.42 for GHD and 10.12±2.9 for ISS, p≤0.0001); time from first diagnosis of short stature (as recorded in the Electronic Medical Record) to first GH purchase was 4.8±3.3 years (4.4±3.1 for GHD and 5.0±3.3 for ISS, p=0.0001). Mean treatment period was 3.5±0.95 years (3.6±1.6 for GHD and 3.4±1.9 for ISS, p=0.017), with 79.4% of patients treated for more than 3 years. The overall mean height gain (ΔHtSDS) was 1.35 and 1.37 for GHD and ISS respectively, and was mainly achieved in the first three years. Final height (at age 15 for girls and 17 for boys) was recorded for 624 patients (26.2%) with GHD patients achieving better outcomes than ISS (-1.0±0.82 vs -1.28±0.93 respectively, p=0.0002). Good adherence (PDC >80%) was achieved in 78.2% of the cohort during the first year, 57.6% in the second, and 68.1% in the third. GHD patients had better adherence than ISS (67.3% vs 58.7%). Conclusions: This large real-life study of treatment patterns in Israel revealed that children initiate GHT a long period after initial recognition of short stature, belong mainly to the upper SES, and have suboptimal adherence from the second year of therapy. This was most pronounced in the ISS group. Over-representation of the upper SES among those receiving GHT reflects treatment bias. Appropriate referral, diagnosis and follow up care may result in better treatment outcomes with GHT.