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Completed

NCT Number: NCT05169619

Prevalence and Characterisation of Asthma Patients According to Disease Severity in Portugal

This study aims to determine the prevalence of Asthma, Difficult-to-Treat and Severe Asthma in Portugal, and characterize patients to better understand their disease characteristics, treatment profile and health care resource use to improve clinical management of the disease.

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Key information

Conditions

Asthma Bronchial Diseases Hypersensitivity Hypersensitivity, Immediate Immune System Diseases Lung Diseases Lung Diseases, Obstructive Respiratory Hypersensitivity Respiratory Tract Diseases

Age range

18 year and older

Sex eligibility

All sexes

Study type

Observational

Primary location

Research Site, Alpendorada, Portugal

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About this study

Data on the epidemiology of asthma in Portugal were mainly grounded in studies using questionnaires and covering limited age groups. Studies assessing the prevalence of asthma diagnosis and of its sub-groups with more accurate methods are therefore needed This study aims to determine the prevalence of asthma, difficult-to-treat and severe asthma in Portugal, and to characterize patients to better understand their disease characteristics, treatment profile and health care resource use to improve clinical management of the disease.

We will conduct a population-based nationwide study with a multicentre stepwise approach, enrolling 7500 adult subjects, randomly selected, from the Portuguese National Health Service patients' database of 38 primary care centres:

STAGE 0 - Phone call invitation and enrolment of participants STAGE 1 - Telephone interview survey to assess respiratory symptoms. STAGE 2 - Clinical assessment, diagnostic confirmation, and patient characterization STAGE 3 - Characterization of asthma patients (sub-group) and characterization of difficult- to-treat asthma & severe asthma patients after 3 months follow up period.

Who can participate

Healthy volunteers accepted: Yes

Only the study team can determine whether someone qualifies for participation.

Inclusion criteria

  • Adults =>18 years old registered in Portuguese National Health service patients' database of primary care units.
  • Give voluntary signed informed consent,
  • Ability to understand ans answer questionnaires.

Exclusion criteria

  • Participants that have a physical condition that could interfere with the study assessments or prevent the participant from adequately participating in the study (e.g. mobility problems, not able to perform spirometry,…)

Treatment and study plan

Primary outcomes

  1. Proportion of participants with asthma, difficult-to-treat asthma, and severe asthma

    Time frame: From date of inclusion until the end of the study currently planned (2,5 years)

    Ratio between the total number of participants with confirmed asthma, difficult-to-treat asthma, and severe asthma and the total number of participants

Secondary outcomes

  1. Subject's characteristics - Age

    Time frame: From date of inclusion until the end of the study currently planned (2,5 years)

    Years

  2. Subject's characteristics - Living in a city or rural community

    Time frame: From date of inclusion until the end of the study currently planned (2,5 years)

    Postal code

  3. Subject's characteristics - Family history

    Time frame: From date of inclusion until the end of the study currently planned (2,5 years)

    Family history of asthma and asthma death and type of relationship

  4. Subject's characteristics - Comorbidities and allergies

    Time frame: From date of inclusion until the end of the study currently planned (2,5 years)

    List of comorbidities with major impact on asthma outcomes

  5. Subject's characteristics - Obesity

    Time frame: From date of inclusion until the end of the study currently planned (2,5 years)

    WHO classification of body mass index

  6. Subject's characteristics - Physical activity

    Time frame: From date of inclusion until the end of the study currently planned (2,5 years)

    Using the brief physical activity assessment questionnaire. This brief physical activity assessment has only two questions and subjects are scored on < 4 (Insufficiently" active) and ⩾4 ("Sufficiently" active).

  7. Subject's characteristics - Health related quality of life

    Time frame: From date of inclusion until the end of the study currently planned (2,5 years)

    Using mini AQLQ Questionnaire AQLQ is a multiple-choice questionnaire for patients with asthma, each choice is assigned a score 1-7. There are 15 questions to answer. The total score is calculated and ranges between 15 and 105. Lower scores indicate worse quality of life.

  8. Subject's characteristics - Healthcare resource use and costs

    Time frame: From date of inclusion until the end of the study currently planned (2,5 years)

    a) Direct resources will include number of inpatient admissions, emergency and hospital visits, medical appointments, diagnostic tests previously performed for asthma treatment in the last 12 months. b) Indirect resources will include reduced productivity of Asthma patients through an ad-hoc questionnaire about absenteeism (work and school days lost because of asthma) and presenteeism (reduced productivity due to asthma) in the last 12 months.

  9. Subject's characteristics - Referral

    Time frame: From date of inclusion until the end of the study currently planned (2,5 years)

    number of patients that should be referral for asthma specialist hospital Consultation or that were referred to Severe Asthma consultation

  10. Disease Characteristics - Age of Asthma onset

    Time frame: From date of inclusion until the end of the study currently planned (2,5 years)

    Age of Asthma onset

  11. Disease Characteristics - Asthma symptoms

    Time frame: From date of inclusion until the end of the study currently planned (2,5 years)

    According to Control of Allergic Rhinitis and Asthma Test (CARAT). CARAT is a 10-item validated Portuguese questionnaire, which allows for the simultaneous assessment of allergic rhinitis and asthma (ARA) control. A score above 24 (min. 0; max. 30) identifies controlled asthma.

  12. Disease Characteristics - Pulmonary function tests

    Time frame: From date of inclusion until the end of the study currently planned (2,5 years)

    Spirometry and reversibility testing

  13. Disease Characteristics - Inflammatory biomarkers

    Time frame: From date of inclusion until the end of the study currently planned (2,5 years)

    Fractional exhaled nitric oxide (FeNO) test and blood eosinophil and neutrophil count,

  14. Disease Characteristics - Exacerbations

    Time frame: From date of inclusion until the end of the study currently planned (2,5 years)

    Number of exacerbations in the past year

  15. Disease Characteristics - Emergency room (ER) visits

    Time frame: From date of inclusion until the end of the study currently planned (2,5 years)

    Number of visits to emergency room (ER) within the past year

  16. Disease Characteristics - Hospital admissions

    Time frame: From date of inclusion until the end of the study currently planned (2,5 years)

    Number of hospital admissions and mean length of hospital stay in the past year

  17. Disease Characteristics - Disease control

    Time frame: From date of inclusion until the end of the study currently planned (2,5 years)

    According to Control of Allergic Rhinitis and Asthma Test (CARAT). CARAT is a 10-item validated Portuguese questionnaire, which allows for the simultaneous assessment of allergic rhinitis and asthma (ARA) control. A score above 24 (min. 0; max. 30) identifies controlled asthma.

  18. Treatment Patterns - Treatment profile (current and last year)

    Time frame: From date of inclusion until the end of the study currently planned (2,5 years)

    Stage of GINA treatment step according to GINA guidelines

  19. Treatment Patterns - Treatment adherence

    Time frame: From date of inclusion until the end of the study currently planned (2,5 years)

    Assessed using a Visual Analogue Scale (VAS) from 0 to 100, 0 means poor adherence and 100 good adherence

  20. Treatment Patterns - Inhalation technique

    Time frame: From date of inclusion until the end of the study currently planned (2,5 years)

    Assessed by the clinician using national checklists

  21. Subject's characteristics - Gender

    Time frame: From date of inclusion until the end of the study currently planned (2,5 years)

    Male/Female

  22. Subject's characteristics - Marital status

    Time frame: From date of inclusion until the end of the study currently planned (2,5 years)

    Single, Married / De facto Union, Separated / Divorced, Widowed

  23. Subject's characteristics - socio-economic and education level

    Time frame: From date of inclusion until the end of the study currently planned (2,5 years)

  24. Subject's characteristics - occupational status

    Time frame: From date of inclusion until the end of the study currently planned (2,5 years)

  25. Subject's characteristics - Smoking status & environmental tobacco smoke

    Time frame: From date of inclusion until the end of the study currently planned (2,5 years)

  26. Subject's characteristics - Health related quality of life

    Time frame: From date of inclusion until the end of the study currently planned (2,5 years)

    Using EQ-5D. EQ-5D is a questionnaire which include five dimensions (mobility, self-care, usual activities, pain/discomfort, anxiety/depression). and is used to evaluate the quality of life. Each dimension in the EQ-5D-5L has five response levels: no problems (Level 1); slight; moderate; severe; and extreme problems (Level 5). There are 3,125 possible health states defined by combining one level from each dimension, ranging from 11111 (full health) to 55555 (worst health).

Sponsors and collaborators

Lead sponsor

AstraZeneca

Industry

Collaborators

  • Universidade do Minho - ICVS
  • Universidade do Porto

Registry information

Official study title

Epi-Asthma: Prevalence and Characterisation of Asthma Patients According to Disease Severity in Portugal

Acronym: Epi-Asthma

Important dates

Study start
2021
Primary completion
2024
Study completion
2024
First posted
Dec 27, 2021
Registry last updated
Mar 6, 2025

OpenTrials presents study information sourced from ClinicalTrials.gov. The official registry record should be consulted for the latest information.

View the official ClinicalTrials.gov record (opens in a new tab)

This listing is for discovery and informational purposes only. It is not medical advice, does not guarantee that a study is recruiting, and does not determine eligibility. Contact the study team and a qualified healthcare professional when considering participation.

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