Lung function in adult patients with osteogenesis imperfecta: a cohort study

Area of Science:

• Pulmonary Medicine
• Genetics
• Rheumatology

Background:

• Osteogenesis imperfecta (OI) is a rare genetic disorder affecting collagen, leading to bone fragility and deformities.
• OI is linked to increased respiratory issues, but lung function changes over time in adults remain poorly understood.

Purpose of the Study:

• To investigate the natural history of lung function in a cohort of adult patients with Osteogenesis Imperfecta.
• To identify factors associated with lung function impairment and changes over time in OI patients.

Main Methods:

• Longitudinal study of 46 adult OI patients (≥15 years) with spirometry data from 2012-2023.
• Linear regression analyzed baseline spirometry associations with clinical factors; mixed linear regression assessed changes over time.
• Models were adjusted for age, sex, height, and OI type (Sillence classification).

Main Results:

• 24% of patients had abnormal spirometry at baseline (restrictive, obstructive, or mixed patterns).
• Older age correlated with lower FEV1 and FEV1/FVC. Asthma history was linked to higher FEV1 and FVC.
• Smokers showed a faster decline in FEV1/FVC. Specific collagen gene mutations (COL1A2 vs. COL1A1) were associated with lower FVC.
• After adjustments, FEV1 and FVC showed a significant annual increase over the follow-up period.

Conclusions:

• Adult OI patients exhibit an annual increase in FEV1 and FVC, suggesting improved lung compliance possibly due to collagen defects.
• Pulmonary changes in OI result from a complex interplay between increased lung compliance and reduced thoracic volume from skeletal deformities.