Original Article

Survival Analysis of Patients with Brain Stroke in the Presence of Competing Risks: A Weibull Parametric Model


Introduction: This study aimed to assess the association between the survival of patients and outcomes in Brain Stroke (BS) in the presence of competing risks utilizing a Weibull parametric model. 

Methods: In this longitudinal study, 332 patients with BS were attended from Imam Khomeini Hospital in Ardabil, Iran. The stroke was diagnosed according to the medical history, current symptoms, and brain imaging during June 2008 and 2018. The survival of the patients, as the primary outcome, was modeled utilizing the best-chosen Weibull model in the presence of competing risks, including stroke and other factors (heart disease, blood pressure, etc.). 

Results: Older age at diagnosis (59-68 years: hazard ratio [HR]=2.27; 90% confidence interval [CI]: 1.65 to 3.12; 69-75 years: HR=4.79; 95% CI: 3.56 to 6.44; ≥76 years: HR, 4.92; 95% CI: 3.55 to 6.80), being a male (HR, 1.39; 95% CI: 1.11 to 1.75), being unemployed (HR, 1.44; 95% CI: 1.39 to 1.82), having heart disease (HR, 1.68; 95% CI: 1.38 to 2.06), and hemorrhagic stroke (HR, 2.21; 95% CI: 1.378to 2.75) were directly related to death from BS. Older age at diagnosis (59-68 years: HR, 18.01; 90% CI, 5.33 to 64.92; 75-69 years: HR, 18.56; 95% CI: 6.97 to 86.57; ≥76 years: HR, 28.90; 95% CI: 15.77 to 218.49), and urban residence (HR, 0.46; 90% CI, 0.28 to 0.77) were directly related to death from other causes.

Conclusion: The recognition of the influential factors on the mortality of BS patients can allow increasing their survival. 

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IssueVol 7 No 3 (2021) QRcode
SectionOriginal Article(s)
DOI https://doi.org/10.18502/jbe.v7i3.7295
Stroke Risk factors Survival analysis Competing risk Weibull Model

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How to Cite
Norouzi S, Fallah R, Shamshirgaran SM, Farzipoor F, Asghari Jafarabadi M. Survival Analysis of Patients with Brain Stroke in the Presence of Competing Risks: A Weibull Parametric Model. JBE. 2021;7(3):235-243.