Clinical outcomes and medical management of achondroplasia in <scp>Japanese</scp> children: A retrospective medical record review of clinical data
Hiroyuki Saitou, Taichi Kitaoka, Takuo Kubota, Junko Kanno, Hiroshi Mochizuki, Toshimi Michigami, Kosei Hasegawa, Ikuma Fujiwara, Takashi Hamajima, Daisuke Harada, Y. Seki, Keisuke Nagasaki, Sumito Dateki, Noriyuki Namba, Hirofumi Tokuoka, Jeanne M. Pimenta, Shelda Cohen, Keiichi Ozono
Abstract
Achondroplasia (ACH) is a rare, autosomal dominant skeletal dysplasia characterized by short stature, characteristic facial configuration, and trident hands. Before vosoritide approval in Japan, patients with ACH could start growth hormone (GH) treatment at age 3 years. However, ACH and its treatment in young Japanese children have not been studied. This retrospective, longitudinal, medical records-based cohort study (before vosoritide approval) summarized symptoms, complications, monitoring, surgery/interventions, and height with/without GH in Japanese patients with ACH <5 years. Complications were observed in 89.2% of all 37 patients; 75.7% required surgery or intervention. All patients were monitored by magnetic resonance imaging; 73.0% had foramen magnum stenosis, while 54.1% had Achondroplasia Foramen Magnum Score 3 or 4. Of 28 GH-treated patients, 22 initiating at age 3 years were generally taller after 12 months versus 9 non-GH-treated patients. Mean annual growth velocity significantly increased from age 2 to 3 versus 3 to 4 years in GH-treated patients (4.37 vs. 7.23 cm/year; p = 0.0014), but not in non-GH-treated patients (4.94 vs. 4.20 cm/year). The mean height at age 4 years with/without GH was 83.6/79.8 cm. These results improve our understanding of young patients with ACH in Japan and confirm that early diagnosis of ACH and monitoring of complications help facilitate appropriate interventions.