Cryptogenic Organising Pneumonia (COP) is an understudied lung disease characterised by presence of granulation tissue within the alveolar ducts and alveoli. While prognosis of patients with COP is generally positive there remains a paucity of information on the condition in the academic literature. This abstract presents the largest real-world study of COP in Chronic lymphocytic Leukaemia (CLL) patients to date.
A retrospective cohort study utilising the IMS Pharmetrics Plus database. A CLL patient cohort was identified using ICD9/10 codes; patients with previous history of COP prior to CLL diagnosis were excluded from the analysis. As a comparator, a random 5% sample of all patients with no history of CLL was taken. Crude Incidence rates (CR) of COP were estimated in both groups. A Poisson regression model (PRM) was fitted to estimate the age and sex adjusted incidence rate ratio (IRR) of experiencing COP in CLL patients versus those with no history of CLL. Tests for trend were conducted for age and sex.
A total of 64,773 CLL and 3,201,48 non-CLL patients were included in the study. The CLL cohort comprised of 59% males with a total of 436 patients experiencing COP. The non-CLL cohort comprised of 47% males with 1,971 patients experiencing COP. The CR of COP in the CLL cohort was 2.4 (95% CI 2.2- 2.61) per 1,000 person years (py) and 0.20 (95% CI 0.19- 0.21) per 1,000 py in the non CLL cohort. An age and sex adjusted PRM estimated an IRR of 7.7 (95% CI 6.9- 8.68, p-value <0.001). A significant trend of increasing COP incidence was observed for age (p-value <0.001). However, no differences found for gender.
This study indicated that CLL patients had a higher rate of experiencing an episode of COP as opposed to non-CLL patients, adjusted for age and sex. As COP is difficult to distinguish from the infectious and non-infectious inflammatory pulmonary process in CLL patients, awareness of this increased risk may lead to earlier diagnosis and institution of treatment of COP. The role of co-morbidities and co-medications will be investigated in further analyses.
Clinical trial identification
Legal entity responsible for the study
Gilead Sciences Gilead Sciences.
I. Faghmous, H. Ramroth, C. Aguilar, A. Van Troostenburg, P. Badyal: Gilead Sciences.