Persistence to growth hormone treatment and clinical characteristics of pediatric patients with growth hormone deficiency: A retrospective cohort study of data from the Japan Medical Data Center claims database.

Limited real-world data are available on persistence to growth hormone replacement therapy (GHRT) in Japan. Therefore, we used the Japan Medical Data Center claims database to retrospectively investigate persistence with GHRT in patients with pediatric growth hormone deficiency (pGHD). We identified 1,020 patients with pGHD treated with GHRT. The mean age at initial diagnosis was 7.5 ± 3.8 years, and we found a bimodal pattern in age, with peaks at 3 and 12 to 13 years of age; the peaks were more pronounced in male patients. After excluding patients with early withdrawal, 1,016 patients were eligible for persistence analysis. The time to initial treatment discontinuation, i.e., the first prescription-free period of 182 days (6 months) or more, for 50% of the patients was 2,526 days, which was similar to that of treatment completion (2,626 days). Most patients persisted with GHRT until they completed treatment, but 24 out of 1,016 (2.4%) had a treatment discontinuation. The mean proportion of days covered was 89.8%. Being female (hazard ratio [95% CI]: 1.85 [1.36-2.51]) and older age at diagnosis (1.50 [1.41-1.60]) were associated with shorter time to discontinuation. This finding suggests that most patients persist with GHRT until puberty. In conclusion, although most Japanese patients with pGHD appear to persist well with GHRT, some complete GHRT before puberty. Additionally, there are patients diagnosed and starting treatment just before puberty. Therefore, continued efforts towards early referral and diagnosis are important.