Recognition of Serious Infections in the Elderly (ROSIE)

Recognition of Serious Infections in the Elderly: Developing a Diagnostic Prediction Rule Based on Clinical Features and Blood Tests to Help Physicians Safely Rule Out a Serious Infection in an Older Patient Presenting to Ambulatory Care

The aim of this diagnostic accuracy study is to develop a clinical prediction rule based on signs, symptoms, patient characteristics and blood tests, to be used in ambulatory care to help physicians safely rule out a serious infection in an older patient.

It will be performed in general practices and emergency care departments across Flanders (Belgium).

Study Overview

• Status: Completed
• Conditions: Infection
• Intervention / Treatment: Diagnostic test: signs and symptoms, blood tests

Detailed Description

This is a cross-sectional diagnostic cohort study in older adults presenting to ambulatory care, including a follow-up period of 30 days. This study will be used to construct an algorithm consisting of clinical features and blood test results to identify serious infections.

The study will run in ambulatory care in Flanders. Recruitment is expected to last 2.5 years, with each patient entering the study only once. Older adults will be approached for possible participation in the study by practice staff. There is only one study visit.

Those who agree to participate via written informed consent will have demographics and clinical features recorded. A blood sample will be taken in all participants on study entry. Follow-up information for all participants will be collected using electronic medical record notes (EMD) and patient diaries.

Treatment and other management decisions will be left to the treating physicians' discretion.

• Study Type: Observational
• Enrollment (Actual): 493

Contacts and Locations

• Study Contact: Name: Thomas Struyf, MS; Phone Number: +32495280329; Email: thomas.struyf@kuleuven.be
• Study Contact Backup: Name: Ann Van den Bruel, MD, PhD; Email: ann.vandenbruel@kuleuven.be

Study Locations

• Belgium
  • Antwerp, Belgium
    • De Wijkpraktijk
  • Brasschaat, Belgium
    • De Leeuwenkaart
  • Gelrode, Belgium
    • Huisartsenpraktijk Arcade
  • Heers, Belgium
    • De Bilter 28
  • Leuven, Belgium
    • Emergency Department Heilig Hart hospital Leuven
  • Leuven, Belgium
    • Emergency Department University Hospitals Leuven
  • Malle, Belgium
    • Emergency Department St.-Jozef Hospital Malle
  • Mortsel, Belgium
    • DRLA
  • Paal, Belgium
    • De Driehoek Paal
  • Sint-Truiden, Belgium
    • Huisartspraktijk Brustempoort
  • Wilrijk, Belgium
    • Onspraktijk
  • Limburg
    • Paal, Limburg, Belgium, 3583
      • De Driehoek Paal

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 65 years and older (Older Adult)
• Accepts Healthy Volunteers: No

• Sampling Method: Non-Probability Sample

Study Population

All acutely ill adults aged 65 years or older presenting to ambulatory care in whom a physician suspects an infection will be eligible. Ambulatory care is defined as in-hours general practice and emergency care.

Description

Inclusion Criteria:

• Aged 65 years or older
• Presenting to a general practice with an acute illness with a maximum duration of 10 days since onset
• Suspicion of infectious disease (this may include suspicion of an acute exacerbation of COPD)
• Patient or proxy of the patient is willing and able to give informed consent for participation.

Exclusion Criteria:

The participant may not enter the study if any of the following apply:

• Too clinically unstable to waste time on study procedures
• Indwelling catheter in situ
• Immunocompromised or currently receiving medication for systemic immune-suppression, including corticosteroids
• Being admitted to hospital for longer than 24 hours less than 7 days before study entry, or having undergone surgery in the previous 30 days
• Living in a nursing home (both short term and long term stay) (only in general practice cohort)
• Patient was already included in the study

Study Plan

How is the study designed?

Design Details

• Observational Models: Cohort
• Time Perspectives: Prospective

Number of groups / cohorts

2

Cohorts and Interventions

Group / Cohort	Intervention / Treatment
Emergency care; Consecutive enrolment of acutely ill older adults in emergency care	Diagnostic test: signs and symptoms, blood tests; signs and symptoms as observed by the treating physician + blood tests (CRP, Procalcitonin, White blood cell count)
General practice; Consecutive enrolment of acutely ill older adults in general practice	Diagnostic test: signs and symptoms, blood tests; signs and symptoms as observed by the treating physician + blood tests (CRP, Procalcitonin, White blood cell count)

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Diagnostic accuracy 1	Sensitivity and specificity of clinical prediction rules that are based on signs, symptoms, patient characteristics with and without blood tests, to be used in ambulatory care to help physicians safely rule out a serious infection in an older patient	30 days

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Diagnostic accuracy 2	Sensitivity, specificity, positive and negative predictive value and likelihood ratios of individual signs, symptoms, patient characteristics and blood tests for diagnosing a serious infection in persons aged ≥65 years	30 days

Other Outcome Measures

Outcome Measure	Measure Description	Time Frame
Net benefit: number of patients correctly classified as having a serious infection	To assess the added value of prediction model based decisions over treat all and treat none at clinically relevant thresholds	30 days
Diagnostic accuracy 3	Sensitivity, specificity, positive and negative predictive value and likelihood ratios of tests across the most often occurring infection types	30 days
Descriptive 1: Prevalence (%) of serious infections in the study population	To investigate the potential for incorporation bias (diagnostic review bias) when establishing the reference standard in an expert review panel, with and without information on biomarker results.	30 days
Descriptive 2: multivariate analysis (no outcome)	To describe features independently associated with a physicians' gut feeling of serious infection in an older patient	30 days
Diagnostic accuracy 4	Sensitivity and specificity of the developed prediction rules compared to existing prediction rules	30 days
Diagnostic accuracy, sensitivity analysis	Sensitivity and specificity of the prediction rules taking all-cause mortality versus mortality due to infection as an outcome	30 days

Collaborators and Investigators

• Sponsor: KU Leuven
• Investigators: Principal Investigator: Ann Van den Bruel, MD, PhD, Department of Public Health and Primary Care, KU leuven

Study record dates

Study Major Dates

• Study Start (Actual): October 16, 2020
• Primary Completion (Actual): August 3, 2023
• Study Completion (Actual): August 3, 2023

Study Registration Dates

• First Submitted: July 30, 2020
• First Submitted That Met QC Criteria: August 13, 2020
• First Posted (Actual): August 18, 2020

Study Record Updates

• Last Update Posted (Actual): August 7, 2023
• Last Update Submitted That Met QC Criteria: August 3, 2023
• Last Verified: August 1, 2023

More Information

Terms related to this study

• Keywords: diagnosis; geriatric; ambulatory care; general practice; emergency care
• Additional Relevant MeSH Terms: Pathologic Processes; Disease Attributes; Infections; Communicable Diseases
• Other Study ID Numbers: S63771

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No