Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2021 May;8(1):e000794.
doi: 10.1136/bmjresp-2020-000794.

Survival models to support shared decision-making about advance care planning for people with advanced stage cystic fibrosis

Affiliations

Survival models to support shared decision-making about advance care planning for people with advanced stage cystic fibrosis

Negin Hajizadeh et al. BMJ Open Respir Res. 2021 May.

Abstract

Background: For people with advanced stage cystic fibrosis (CF), tailored survival estimates could facilitate preparation for decision-making in the event of acutely deteriorating respiratory function.

Methods: We used the US CF Foundation national database (2008-2013) to identify adult people with incident advanced stage CF (forced expiratory volume in 1 s (FEV1) ≤45% predicted). Using the lasso method for variable selection, we divided the dataset into training and validation samples (2:1), and developed two multivariable Cox proportional hazards models to calculate probabilities of survival from baseline (T0 model), and from 1 year after (T12 model). We also performed Kaplan-Meier survival analyses.

Results: 4752 people were included. For the T0 model, FEV1; insurance; non-invasive ventilation; supplemental oxygen; Burkholderia colonisation; cirrhosis; depression; dialysis; current smoking; unclassifiable mutation class and cumulative CF exacerbations predicted increased mortality. Baseline transplant evaluation status of 'accepted, on waiting list' predicted decreased mortality. For the T12 model, interim decrease in FEV1 >10%, and pulmonary exacerbations additionally increased predicted mortality. Lung transplantation was associated with lower mortality. Of the 4752, 93.5%, 86.4%, 79.7% and 73.9% survived to 1, 2, 3 and 4 years, respectively, without considering any confounding variables. The models had moderate predictive ability indicated by the area under the time-dependent receiver operating characteristic curve (0.787, 95% CI 0.769 to 0.794 for T0 model; and 0.779, 95% CI 0.767 to 0.797 for T12 model).

Conclusion: We have developed models predicting survival in people with incident advanced stage CF, which can be reapplied over time to support shared decision-making about end-of-life treatment choices and lung transplantation. These estimates must be updated as data become available regarding long-term outcomes for people treated with CF transmembrane conductance regulator modulators.

Keywords: cystic fibrosis; lung transplantation.

PubMed Disclaimer

Conflict of interest statement

Competing interests: None declared.

Figures

Figure 1
Figure 1
Study flow diagram. CF, cystic fibrosis; FEV1, forced expiratory volume in 1 s.
Figure 2
Figure 2
Kaplan-Meier survival curves for T0 cohort (A)and T1 cohort (B). CF, cystic fibrosis.
Figure 3
Figure 3
Kaplan-Meier survival curve for patients who received lung transplantation. CF, cystic fibrosis.

References

    1. Ramsey BW. Management of pulmonary disease in patients with cystic fibrosis. N Engl J Med 1996;335:179–88. 10.1056/NEJM199607183350307 - DOI - PubMed
    1. Corey M, Edwards L, Levison H, et al. . Longitudinal analysis of pulmonary function decline in patients with cystic fibrosis. J Pediatr 1997;131:809–14. 10.1016/S0022-3476(97)70025-8 - DOI - PubMed
    1. Rosenbluth DB, Wilson K, Ferkol T, et al. . Lung function decline in cystic fibrosis patients and timing for lung transplantation referral. Chest 2004;126:412–9. 10.1378/chest.126.2.412 - DOI - PubMed
    1. Street RL. Aiding medical decision making: a communication perspective. Med Decis Making 2007;27:550–3. 10.1177/0272989X07307581 - DOI - PubMed
    1. Chewning B, Bylund CL, Shah B, et al. . Patient preferences for shared decisions: a systematic review. Patient Educ Couns 2012;86:9–18. 10.1016/j.pec.2011.02.004 - DOI - PMC - PubMed

Publication types