Evidence map›Paper›PMID 34556999›Full record

ArticleJournal of asthma and allergy2021

Severe Asthma in a General Population Study: Prevalence and Clinical Characteristics.

Lina Rönnebjerg, Malin Axelsson, Hannu Kankaanranta, Helena Backman, Madeleine Rådinger, Bo Lundbäck, Linda Ekerljung

Open access · goldAbstract read
In one paragraph

Article in Journal of asthma and allergy, 2021. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 48 papers.

0numbers the graph read from it
0cells of the map it votes in
48citing papers in PubMed
8.6field-weighted citation impact, top 1% of its field
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

48 citing papers in PubMed, 105 citations in OpenAlex.

  1. Article
  2. Observational
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  5. Well-controlled asthma does not adversely affect outcomes following anterior cervical discectomy and fusion.European spine journal : official publication of the European Spine Society, the European Spinal Deformity Society, and the European Section of the Cervical Spine Research Society · 2026
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  10. Digitally assessed home FEVBMJ open respiratory research · 2025
    Article
  11. Review
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  13. Risk factors for asthma exacerbations.The journal of allergy and clinical immunology. Global · 2025
    Article
  14. Article
  15. Article
  16. Review
  17. Article
  18. Article
  19. Article
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4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

7 authors at 4 institutions in 2 countries.

Lina RönnebjergKrefting Research Centre, Department of Internal Medicine and Clinical Nutrition, Institute of Medicine, University of Gothenburg, Gothenburg, Sweden.ORCID 0000-0003-0598-1066
Malin AxelssonDepartment of Care Science, Faculty of Health and Society, Malmö University, Malmö, Sweden.ORCID 0000-0001-5493-8334
Hannu KankaanrantaKrefting Research Centre, Department of Internal Medicine and Clinical Nutrition, Institute of Medicine, University of Gothenburg, Gothenburg, Sweden.ORCID 0000-0001-5258-0906
Helena BackmanDepartment of Public Health and Clinical Medicine, Umeå University, Umeå, Sweden.ORCID 0000-0002-0553-8067
Madeleine RådingerKrefting Research Centre, Department of Internal Medicine and Clinical Nutrition, Institute of Medicine, University of Gothenburg, Gothenburg, Sweden.ORCID 0000-0002-0652-7378
Bo LundbäckKrefting Research Centre, Department of Internal Medicine and Clinical Nutrition, Institute of Medicine, University of Gothenburg, Gothenburg, Sweden.ORCID 0000-0002-7196-3651
Linda EkerljungKrefting Research Centre, Department of Internal Medicine and Clinical Nutrition, Institute of Medicine, University of Gothenburg, Gothenburg, Sweden.ORCID 0000-0001-5784-0041
University of Gothenburg · SEMalmö University · SETampere University · FIUmeå University · SE

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

purposeCurrent guidelines primarily use medication levels to distinguish severe asthma from other types of asthma. In addition, severe asthma must also be uncontrolled at high-intensity treatment or become uncontrolled if treatment level is decreased. To date, only a few studies have used this definition to investigate the prevalence and clinical characteristics of severe asthma in population-based samples. Therefore, the aim of this study was to evaluate the prevalence and clinical characteristics of individuals with severe asthma in the population-representative West Sweden Asthma Study. MATERIALS AND

methodsIn this cross-sectional population-based study, a randomly selected sample (n=1172) and a separate asthma sample (n=744) underwent clinical examinations, completed a structured interview and responded to questionnaires. Severe asthma was defined as at least one feature of uncontrolled asthma despite treatment in line with the Global Initiative for Asthma (GINA) steps 4/5. This treatment level required a minimum medium dose of inhaled corticosteroids (ICS) plus a second controller or oral corticosteroids.

resultsThe prevalence of severe asthma was 1.1% in the adult random sample and 9.5% within the asthma sample. Individuals with severe asthma were older and had more symptoms, activity limitations, heart disease and blood neutrophils compared to those with other asthma. They also had lower lung function and despite these impairments, 32% did not have annual contact with a healthcare provider.

conclusionThe prevalence of severe asthma was higher compared to previous studies, and many individuals with severe asthma did not have regular contact with healthcare providers. Due to the high burden of symptoms and impairments for individuals with severe asthma, it is important that the healthcare system implement strategies to improve follow-up and evaluate these patients according to existing guidelines.

Indexed as

asthma controlasthma epidemiologyasthma-medicationasthma severity symptomslung function

Identifiers

PMID34556999
PMCPMC8454418
OpenAlexW3201482726

What OpenQuestion holds

Textmetadata
LicenceCC BY-NC
Read underepoch 390

Registered trials

None linked

Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.