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Open Access 01-12-2016 | Research article

Effects of longitudinal changes in Charlson comorbidity on prognostic survival model performance among newly diagnosed patients with hypertension

Authors: Peter Rymkiewicz, Pietro Ravani, Brenda R. Hemmelgarn, Finlay A. McAlister, Danielle A. Southern, Robin Walker, Guanmin Chen, Hude Quan

Published in: BMC Health Services Research | Issue 1/2016

Abstract

Background

To assess the use of updated comorbidity information over time on ability to predict mortality among adults with newly diagnosed hypertension.

Methods

We studied adults 18 years and older with an incident diagnosis of hypertension from Alberta, Canada. We compared the prognostic performance of Cox regression models using Charlson comorbidities as time-invariant covariates at baseline (TIC) versus models including Charlson comorbidities as time-varying covariates (TVC) using Akaike Information Criterion (AIC) for testing goodness of fit.

Results

The strength of the association between important prognostic clinical variables and mortality varied by modeling technique; for example, myocardial infarction was less strongly associated with mortality in the TIC model (Hazard Ratio 1.07; 95% Confidence Interval (CI): 1.05 to 1.1) than in the TVC model (HR 1.20; 95% CI: 1.18 to 1.22). All TVC models slightly outperformed TIC models, regardless of the method used to adjust for comorbid conditions (individual Charlson Comorbidities, count of comorbidities or indices). The TVC model including all 17 Charlson comorbidities as individual independent variables showed the best fit and performance.

Conclusion

Accounting for changes in patient comorbidity status over time more accurately captures a patient’s health risk and slightly improves predictive model fit and performance than traditional methods using TIC assessment.

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Title: Effects of longitudinal changes in Charlson comorbidity on prognostic survival model performance among newly diagnosed patients with hypertension
Authors: Peter Rymkiewicz
Pietro Ravani
Brenda R. Hemmelgarn
Finlay A. McAlister
Danielle A. Southern
Robin Walker
Guanmin Chen
Hude Quan
Publication date: 01-12-2016
Publisher: BioMed Central
Published in: BMC Health Services Research / Issue 1/2016
Electronic ISSN: 1472-6963
DOI: https://doi.org/10.1186/s12913-016-1910-8

Keynote webinar | Spotlight on medication adherence

Springer Medicine

Effects of longitudinal changes in Charlson comorbidity on prognostic survival model performance among newly diagnosed patients with hypertension

Abstract

Background

Methods

Results

Conclusion

Keynote webinar | Spotlight on medication adherence

Springer Medicine

Abstract

Background

Methods

Results

Conclusion

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