A composite ranking of risk factors for COVID-19 time-to-event data from a Turkish cohort

Ayse Ulgen1, Sirin Cetin2, Meryem Cetin3

  • 1Department of Biostatistics, Faculty of Medicine, Girne American University, Karmi, Cyprus.

Insights

Identifying reliable blood test risk factors for COVID-19 severity is crucial. This study enhances survival analysis using machine learning to pinpoint key indicators for disease progression and recovery.

Area of Science:

  • Clinical Medicine
  • Biostatistics
  • Computational Biology

Background:

  • Reliable identification of routine laboratory blood test risk factors for COVID-19 severity and mortality is vital for patient care and hospital management.
  • Meta-analysis is commonly used to combine study results for reproducibility, but a more robust approach is needed.

Purpose of the Study:

  • To develop a more robust list of risk factors for COVID-19 severity and mortality using routine blood tests.
  • To extend standard survival analysis by incorporating machine learning, multivariable analysis, and analyzing both death and recovery events.

Main Methods:

  • Extended standard survival analysis on time-to-event data in three directions: machine learning prediction, multivariable analysis, and analyzing time-to-hospital release alongside time-to-death.
  • Generated ten ranking lists of risk factors based on these extended analyses.
  • Utilized stepwise variable selection in random survival forest to identify optimal prognostic factors.

Main Results:

  • Identified 20 out of 30 factors reliably associated with faster death or faster recovery from COVID-19.
  • Determined that 10-15 factors can achieve optimal prognosis performance when considering correlations and using stepwise variable selection.
  • The final list of significant risk factors includes calcium, white blood cell and neutrophils count, urea and creatine, d-dimer, red cell distribution widths, age, ferritin, glucose, lactate dehydrogenase, lymphocyte, basophils, anemia-related factors, sodium, potassium, eosinophils, and aspartate aminotransferase.

Conclusions:

  • The proposed extended survival analysis provides a robust method for identifying COVID-19 risk factors from routine blood tests.
  • A refined list of 10-15 key blood test parameters can effectively predict COVID-19 prognosis.
  • These findings can aid in clinical decision-making and hospital resource management for COVID-19 patients.

Related Concept Videos

Relative Risk01:12

Relative Risk

Relative risk (RR) is a statistical measure commonly used in epidemiology to compare the likelihood of a particular event occurring between two groups. This metric is important for evaluating the relationship between exposure to a specific risk factor and the probability of a particular outcome. It plays a crucial role in medical research, public health studies, and risk assessment. Relative risk quantifies how much more (or less) likely an event is to occur in an exposed group compared to an...
398
Bias in Epidemiological Studies01:29

Bias in Epidemiological Studies

Biases can arise at various stages of research, from study design and data collection to analysis and interpretation. Recognizing and addressing these biases is essential to ensure the validity and reliability of epidemiological findings.Broadly speaking, biases in epidemiology fall into three main categories: selection bias, information bias, and confounding. A more detailed description of possible biases is:  
733
Factors Affecting the Risk of Infection01:26

Factors Affecting the Risk of Infection

The hosts' susceptibility to infection depends on several factors. The integrity of the skin and mucous membranes helps protect the body against microbial attacks. When the skin is altered, the chance of infection, limb loss, and even death increases.
The integrity and count of the white blood cells help the body resist pathogens and fight infection. When impaired, it reduces the body's resistance to pathogens. The acidic pH levels of the gastrointestinal, genitourinary tracts, and skin...
12.4K
Comparing the Survival Analysis of Two or More Groups01:20

Comparing the Survival Analysis of Two or More Groups

Survival analysis is a cornerstone of medical research, used to evaluate the time until an event of interest occurs, such as death, disease recurrence, or recovery. Unlike standard statistical methods, survival analysis is particularly adept at handling censored data—instances where the event has not occurred for some participants by the end of the study or remains unobserved. To address these unique challenges, specialized techniques like the Kaplan-Meier estimator, log-rank test, and...
309
Hazard Ratio01:12

Hazard Ratio

The hazard ratio (HR) is a widely used measure in clinical trials to compare the risk of events, such as death or disease recurrence, between two groups over time. It reflects the ratio of hazard rates—the instantaneous risk of the event occurring—between a treatment group and a control group. This measure provides valuable insights into the relative effectiveness of a treatment by assessing how the risk of an event differs between the two groups.
For example, in a clinical trial...
274
Hazard Rate01:11

Hazard Rate

The hazard rate, also known as the hazard function or failure rate, is a statistical measure used to describe the instantaneous rate at which an event occurs, given that the event has not yet happened. From a probabilistic perspective, it represents the likelihood that a subject will experience the event in a very small time interval, conditional on surviving up to the beginning of that interval. In terms of frequency, the hazard rate can be viewed as the ratio of the number of events to the...
196