Background: Risk factor identification is a proven strategy in advancing treatments and preventive therapy for many chronic conditions. Quantifying the impact of those risk factors on health outcomes can consolidate and focus efforts on individuals with specific high-risk profiles. Using multiple risk factors and longitudinal outcomes in 2 independent cohorts, we developed and validated a risk score model to predict mortality in current and former cigarette smokers. Methods: We obtained extensive data on current and former smokers from the COPD Genetic Epidemiology (COPDGene®) study at enrollment. Based on physician input and model goodness-of-fit measures, a subset of variables was selected to fit final Weibull survival models separately for men and women. Coefficients and predictors were translated into a point system, allowing for easy computation of mortality risk scores and probabilities. We then used the SubPopulations and InteRmediate Outcome Measures In COPD Study (SPIROMICS) cohort for external validation of our model. Results: Of 9867 COPDGene participants with standard baseline data, 17.6% died over 10 years of follow-up, and 9074 of these participants had the full set of baseline predictors (standard plus 6-minute walk distance and computed tomography variables) available for full model fits. The average age of participants in the cohort was 60 for both men and women, and the average predicted 10-year mortality risk was 18% for women and 25% for men. Model time-integrated area under the receiver operating characteristic curve statistics demonstrated good predictive model accuracy (0.797 average), validated in the external cohort (0.756 average). Risk of mortality was impacted most by 6-minute walk distance, forced expiratory volume in 1 second and age, for both men and women. Conclusions: Current and former smokers exhibited a wide range of mortality risk over a 10- year period. Our models can identify higher risk individuals who can be targeted for interventions to reduce risk of mortality, for participants with or without chronic obstructive pulmonary disease (COPD) using current Global initiative for chronic Obstructive Lung Disease (GOLD) criteria.
Bibliographical noteFunding Information:
Abbreviations: COPD Genetic Epidemiology, COPDGene®; SubPopulations and InteRmediate Outcome Measures In COPD Study, SPIROMICS; chronic obstructive pulmonary disease, COPD; Global initiative for chronic Obstructive Lung Disease, GOLD; body mass index, BMI; Body mass index-Obstruction-Dyspnea-Exercise capacity index, BODE; computed tomography, CT; forced expiratory volume in 1 second, FEV1; forced vital capacity, FVC; preserved ratio-impaired spirometry, PRISm; 6-minute walk distance, 6MWD; Framingham Risk Score, FRS; longitudinal follow-up program, LFU; modified Medical Resource Council dyspnea scale, mMRC; cardiovascular disease, CVD; segmental airway wall thickening, sAWT; Social Security Death Index, SSDI; area-under-the-curve, AUC; confidence interval, CI; standard deviation, SD Funding Support: The COPDGene® study is funded by National Heart, Lung, and Blood Institute grants U01 HL089897 and U01 HL089856. The COPDGene® study (NCT00608764) is also supported by the COPD Foundation through contributions made to an Industry Advisory Committee comprised of AstraZeneca, Boehringer-Ingelheim, Genentech, GlaxoSmithKline, Novartis, Pfizer, Siemens, and Sunovion. Date of Acceptance: May 15, 2020 Citation: Strand M, Austin E, Moll M, et al. A risk prediction model for mortality among smokers in the COPCGene® study. Chronic Obstr Pulm Dis. 2020;7(4):346-361. doi: https://doi.org/10.15326/jcopdf.7.4.2020.0146
The COPDGene® study is funded by National Heart, Lung, and Blood Institute grants U01 HL089897 and U01 HL089856. The COPDGene® study (NCT00608764) is also supported by the COPD Foundation through contributions made to an Industry Advisory Committee comprised of AstraZeneca, Boehringer-Ingelheim, Genentech, GlaxoSmithKline, Novartis, Pfizer, Siemens, and Sunovion.
© 2020 JCOPDF.
- COPD genetic epidemiology study
- Preserved ratio-impaired spirometry
- Risk score