• A study published in Orphanet Journal of Rare Diseases used Truveta Data to characterize patients with ornithine transcarbamylase deficiency (OTCD), a rare genetic disorder.
• Researchers combined longitudinal EHR data with information extracted from physician notes to better understand symptoms, treatment patterns, and outcomes in real-world clinical practice.
• Among patients with available ammonia measurements, nearly two-thirds (63.2%) experienced at least one hyperammonemia event, highlighting the substantial burden of OTCD.
As researchers work to better understand rare diseases in real-world clinical practice, large-scale datasets are helping provide new insights into conditions that have historically been difficult to study.
A study published in Orphanet Journal of Rare Diseases used Truveta Data to characterize patients with ornithine transcarbamylase deficiency (OTCD), a rare genetic disorder. Researchers examined patient characteristics, treatment patterns, and outcomes in a real-world care setting.
Study snapshot
Researchers identified 214 patients with OTCD between 2016 and 2024 and examined clinical characteristics, treatments, hyperammonemia events, and healthcare utilization. Because OTCD is a rare condition, real-world research has historically been limited by small patient populations, making it difficult to characterize patient experiences in routine clinical practice.
Looking beyond structured data
Important clinical details are not always captured in diagnosis codes and other structured health record fields, particularly for rare diseases. To build a more complete picture of OTCD, researchers supplemented electronic health record (EHR) data with information extracted from clinical notes using natural language processing (NLP).
This approach helped identify symptoms, hyperammonemia events, neurological impairments, and other clinical characteristics documented during routine care. Researchers noted that combining structured EHR data with information from physician notes provided additional insight into the real-world experience of patients with OTCD.
Patients with OTCD experienced substantial disease burden
Researchers identified a wide range of symptoms among patients with OTCD, reflecting the disorder’s impact across multiple body systems. Commonly observed symptoms included personality, emotional, or behavioral changes (38.8%), shallow breathing (29.4%), nausea and vomiting (27.1%), lethargy (25.7%), and headaches (25.2%). Neurological impairments were also identified in nearly 30% of patients.
Among the 68 patients with available ammonia measurements, nearly two-thirds (63.2%) experienced at least one hyperammonemia event. The study also found limited use of ammonia-scavenging medications, treatments designed to help lower ammonia levels in the blood, which were used by 21.0% of patients.
The authors concluded that patients with OTCD experience substantial clinical burden and that current management strategies have limitations, highlighting the need for therapies that more effectively prevent hyperammonemia events and reduce symptom burden.
Read the full study
Clinical characteristics, treatments and outcomes of patients with ornithine transcarbamylase deficiency (OTCD): a retrospective cohort study using a US electronic health record database, Orphanet Journal of Rare Diseases
