Clinical trial NCT05622331: Burden of Respiratory Syncytial Virus (RSV) in Children in Sweden (BRICS): A Retrospective Study in Sweden
Official title: Burden of Respiratory Syncytial Virus (RSV) in Children in Sweden (BRICS): A Retrospective Study in Sweden
Study type: OBSERVATIONAL
Overall status: COMPLETED
Conditions: Respiratory Syncytial Virus (RSV)
Lead sponsor: Sanofi
Sponsor class: INDUSTRY
Collaborators: name: Quantify Research
First posted: 2022-11-18
Enrollment: 1100000
Sex: ALL
Maximum age (years): 5
Standard ages: CHILD
Accepts healthy volunteers: no
Observational model: COHORT
Time perspective: RETROSPECTIVE
Sampling method: NON_PROBABILITY_SAMPLE
Study population: The source population for this study will consist of all children (≤5 years of age) in Sweden with an RSV infection or any acute respiratory infection (ARI) between January 1rst 2001 and latest available date, identified from three sources:

* Primary or secondary diagnosis in hospital care (National Patient Registry)
* Primary or secondary diagnosis in primary care (regional databases)
* Positive RSV laboratory test result (Regional laboratory data) The expected study sample is 38,000 unique pediatric patients with an RSV diagnosis, identified in the National Patient Register between 2001 and 2020. The expected RSV sample size, the non-RSV control population will consist of 80,000-160,000 individuals, matched 1:10. The expected number of ARI infections during the time period is estimated to around 1 million. This totals a study sample of between 1-1.1 million.

Brief summary: Primary Objective:

-Estimate the hospital-associated healthcare resource use (HCRU), and associated costs, of RSV infection in children in comparison to the non-RSV control cohort (general population) and patients with rhinovirus infection.

Secondary Objectives:

* Describe demographic and clinical patient characteristics of RSV infected children.
* Estimate and compare the incidence of RSV infection and acute respiratory infections (ARIs) in children.
* Estimate the mortality associated with RSV infection in children.
* Estimate the social economic burden of RSV infection in children in relation to parents staying home from work to care for their sick child (VAB leave) in comparison to non-RSV control cohort (i.e. parents to children in the general population).

  * Estimate the net days with VAB leave and the compensation disbursed (temporary parental benefit) associated with RSV infection in children.
  * Estimate the indirect costs that can be attributed to VAB leave.
* Examine the medium- and long-term complications associated with an RSV diagnosis in children in comparison to the non-RSV control chart (general population) and patients with rhinovirus infection.
* Examine and describe risk factors associated with an RSV infection in children
* Estimate the healthcare resource use (HCRU), and associated costs, of RSV infection in children, for a subset of patients where primary care data is available, in comparison to the non-RSV control cohort (general population).

Detailed description: The overall study period will be between July 1st 2001 and to latest available date (likely June 30th 2022).

Patients will be identified for inclusion in the study population between July 1st 2006 and June 30th 2021.

Patients will be followed from time of inclusion until end of the study period or until death.

All patients will have an index date corresponding to the date of diagnosis of incident infection in primary and/or hospital care during the identification period. An incident infection is defined as the occurrence of infections more than 30 (\>30) days apart. This implies that a patient can have more than one index date during the study period. Patients that are included in both the RSV cohort and the regional primary care RSV cohort may have two different index dates for the same incident infection, depending on the objective. This is if a patient is first treated in primary care and then hospitalized. The index date is defined differently for the two cohorts, as the first diagnosis in hospital care for the RSV cohort and first diagnosis in primary care OR hospital care for the regional primary care cohort. The non-RSV controls will have the same index date as their matched RSV patient.

The look-back period will be used to inform baseline characteristics as well as patients' medical and diagnosis history. All patients will have possible look-back from birth for information on the patient's hospital care history and from 2005 for information on the patient's prescribed drugs history. The individual look-back and follow-up will depend on the time of inclusion in the study population as well as age at inclusion.

Eligibility criteria: Inclusion Criteria:

•Children (≤5 years of age) with an RSV infection or any acute respiratory infection (ARI) between July 1st 2001 and latest available date, identified in either hospital care, regional primary care or laboratory database.

Exclusion Criteria:

•There are no exclusion criteria for this study.

Primary outcomes:
measure: Short-term healthcare: Number of specialist outpatient visits
timeFrame: Analysis period: July 1st 2006 - July 31st 2021 Reporting period: 30 days from index date
measure: Short-term healthcare: Number of hospitalizations
timeFrame: Analysis period: July 1st 2006 - July 31st 2021 Reporting period: 30 days from index date
measure: Short-term healthcare: Length of hospitalizations
timeFrame: Analysis period: July 1st 2006 - July 31st 2021 Reporting period: 30 days from index date
measure: Short-term healthcare: Number of Intensive Care Unit (ICU) hospitalizations
timeFrame: Analysis period: July 1st 2006 - July 31st 2021 Reporting period: 30 days from index date
measure: Short-term healthcare: Length of ICU hospitalizations
timeFrame: Analysis period: July 1st 2006 - July 31st 2021 Reporting period: 30 days from index date
measure: Short-term healthcare: Number of RSV-related medical/surgical procedures
timeFrame: Analysis period: July 1st 2006 - July 31st 2021 Reporting period: 30 days from index date
measure: Short-term healthcare: Number of dispensed prescriptions of RSV-related medications
timeFrame: Analysis period: July 1st 2006 - July 31st 2021 Reporting period: 30 days from index date
measure: Short-term healthcare: The costs of direct medical (in- and outpatient care)
timeFrame: Analysis period: July 1st 2006 - July 31st 2021 Reporting period: 30 days from index date
measure: Short-term healthcare: The costs of RSV-related medications
timeFrame: Analysis period: July 1st 2006 - July 31st 2021 Reporting period: 30 days from index date
measure: Medium-term healthcare: Number of specialist outpatient visits
timeFrame: Analysis period: July 1st 2006 - July 31st 2021 Reporting period: 12 months from (first) index date
measure: Medium-term healthcare: Number of hospitalizations
timeFrame: Analysis period: July 1st 2006 - July 31st 2021 Reporting period: 12 months from (first) index date
measure: Medium-term healthcare: Length of hospitalizations
timeFrame: Analysis period: July 1st 2006 - July 31st 2021 Reporting period: 12 months from (first) index date
measure: Medium-term healthcare: Number of Intensive Care Unit (ICU) hospitalizations
timeFrame: Analysis period: July 1st 2006 - July 31st 2021 Reporting period: 12 months from (first) index date
measure: Medium-term healthcare: Length of ICU hospitalizations
timeFrame: Analysis period: July 1st 2006 - July 31st 2021 Reporting period: 12 months from (first) index date
measure: Medium-term healthcare: Number of RSV-related medical/surgical procedures
timeFrame: Analysis period: July 1st 2006 - July 31st 2021 Reporting period: 12 months from (first) index date
measure: Medium-term healthcare: Number of dispensed prescriptions of RSV-related medications
timeFrame: Analysis period: July 1st 2006 - July 31st 2021 Reporting period: 12 months from (first) index date
measure: Medium-term healthcare: The costs of direct medical (in- and outpatient care)
timeFrame: Analysis period: July 1st 2006 - July 31st 2021 Reporting period: 12 months from (first) index date
measure: Medium-term healthcare: The costs of RSV-related medications
timeFrame: Analysis period: July 1st 2006 - July 31st 2021 Reporting period: 12 months from (first) index date
Secondary outcomes:
measure: Patient characteristics
timeFrame: Analysis period: July 1st 2006 - June 30th 2021 Reporting period: at index date or during look-back period
measure: Incidence of RSV/ARIs
timeFrame: Analysis period: July 1st 2006 - June 30th 2021 Reporting period: by respiratory years
measure: Number of laboratory-confirmed RSV cases with RSV diagnosis
timeFrame: Analysis period: July 1st 2006 - June 30th 2021 Reporting period: at index date or during look-back period
measure: Number of laboratory-confirmed RSV cases with no RSV diagnosis
timeFrame: Analysis period: July 1st 2006 - June 30th 2021Reporting period: at index date or during look-back period
measure: Number of diagnosed RSV cases with no RSV laboratory tests conducted
timeFrame: Analysis period: July 1st 2006 - June 30th 2021 Reporting period: at index date or during look-back period
measure: Mortality
timeFrame: Analysis period: July 1st 2006 - July 31st 2021 Reporting period: 30 days from index date
measure: Socioeconomic burden: Net days of VAB leave
timeFrame: Analysis period: July 1st 2006 - July 31st 2021 Reporting period: 12 months from (first) index date
measure: Socioeconomic burden: Net VAB leave benefit
timeFrame: Analysis period: July 1st 2006 - July 31st 2021 Reporting period: 12 months from (first) index date
measure: Socioeconomic burden: Indirect costs of VAB leave due to RSV
timeFrame: Analysis period: July 1st 2006 - July 31st 2021 Reporting period: 12 months from (first) index date
measure: Proportion of patients that develop respiratory complications (ICD-10 codes)
timeFrame: Analysis period: July 1st 2006 - July 31st 2021 Reporting period: per year during 5 years from index date
measure: Incidence of RSV per 1000 person-years
timeFrame: Analysis period: July 1st 2006 - July 31st 2021 Reporting period: per year during 5 years from index date
measure: Incidence rate ratios (IRR)
timeFrame: Analysis period: July 1st 2006 - July 31st 2021 Reporting period: per year during 5 years from index date
measure: Hazard ratios (HR)
timeFrame: Analysis period: July 1st 2006 - July 31st 2021 Reporting period: per year during 5 years from index date
measure: Estimation of hazard ratio of each risk factor on being diagnosed with RSV
timeFrame: Analysis period: July 1st 2006 - July 31st 2021Reporting period: look back period
measure: Primary Care: Number of primary care contacts
timeFrame: Analysis period: Date of first available data - July 31st 2021 Reporting period: 30 days from index date
measure: Primary Care: Number of specialized outpatient care visits
timeFrame: Analysis period: Date of first available data - July 31st 2021 Reporting period: 30 days from index date
measure: Primary Care: Number of hospitalizations
timeFrame: Analysis period: Date of first available data - July 31st 2021 Reporting period: 30 days from index date
measure: Primary Care: Length of hospitalizations
timeFrame: Analysis period: Date of first available data - July 31st 2021 Reporting period: 30 days from index date
measure: Primary Care: Number of ICU hospitalizations
timeFrame: Analysis period: Date of first available data - July 31st 2021 Reporting period: 30 days from index date
measure: Primary Care: Length of ICU hospitalizations
timeFrame: Analysis period: Date of first available data - July 31st 2021 Reporting period: 30 days from index date
measure: Primary Care: Number of RSV-related medical/surgical procedures
timeFrame: Analysis period: Date of first available data - July 31st 2021 Reporting period: 30 days from index date
measure: Primary Care: Number of dispensed prescriptions of RSV-related medications
timeFrame: Analysis period: Date of first available data - July 31st 2021 Reporting period: 30 days from index date
measure: Primary Care: The costs of direct medical (in- and outpatient care)
timeFrame: Analysis period: Date of first available data - July 31st 2021 Reporting period: 30 days from index date
measure: Primary Care: The costs of RSV-related medications
timeFrame: Analysis period: Date of first available data - July 31st 2021 Reporting period: 30 days from index date
Other outcomes:
Locations:
Study officials:
affiliation: Sanofi
name: Clinical Sciences & Operations
role: STUDY_DIRECTOR
References: