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Phenotypic characteristics and asthma severity in an East African cohort of adults and adolescents with asthma: findings from the African severe asthma project
  1. Bruce Kirenga1,
  2. Jeremiah Chakaya2,
  3. Getnet Yimer3,
  4. George Nyale4,
  5. Tewodros Haile5,
  6. Winters Muttamba6,
  7. Levicatus Mugenyi6,
  8. Winceslaus Katagira7,
  9. William Worodria8,
  10. Hellen Aanyu-Tukamuhebwa9,
  11. Njira Lugogo10,
  12. Moses Joloba11,
  13. Amsalu Bekele5,
  14. Fred Makumbi11,
  15. Cindy Green12,
  16. Corina de Jong13,
  17. Moses Kamya11 and
  18. Thys van der Molen14
  1. 1College of Health Sciences, Makerere University, Kampala, Uganda
  2. 2Kenya Association of Physicians against TB and Lung Diseases (KAPTLD), Nairobi, Kenya
  3. 3College of Health Sciences, Addis Ababa University, Addis Ababa, Ethiopia
  4. 4Department of Medicine, Kenyatta National Hospital, Nairobi, Kenya
  5. 5College of Health Sciences, Addis Ababa University, Addis Ababa, Ethiopia
  6. 6Lung Institute, Makerere University College of Health Sciences, Kampala, Uganda
  7. 7Lung Institute, Makerere University College of Health Sciences, Kampala, Uganda
  8. 8Mulago National Referral Hospital, Uganda Ministry of Health, Kampala, Uganda
  9. 9Mulago National Referral Hospital, Uganda Ministry of Health, Kampala, Uganda
  10. 10Internal Medicine, University of Michigan, Ann Arbor, Michigan, USA
  11. 11College of Health Sciences, Makerere University, Kampala, Uganda
  12. 12Medicine, Duke University School of Medicine, Durham, North Carolina, USA
  13. 13Department of General Practice, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
  14. 14University Medical Center Groningen (UMCG), University of Groningen, Groningen, Netherlands
  1. Correspondence to Dr Bruce Kirenga; brucekirenga{at}


Rationale The relationship between clinical and biomarker characteristics of asthma and its severity in Africa is not well known.

Methods Using the Expert Panel Report 3, we assessed for asthma severity and its relationship with key phenotypic characteristics in Uganda, Kenya and Ethiopia. The characteristics included adult onset asthma, family history of asthma, exposures (smoking and biomass), comorbidities (HIV, hypertension, obesity, tuberculosis (TB), rhinosinusitis, gastro-oesophageal disease (GERD) and biomarkers (fractional exhaled nitric oxide (FeNO), skin prick test (SPT) and blood eosinophils). We compared these characteristics on the basis of severity and fitted a multivariable logistic regression model to assess the independent association of these characteristics with asthma severity.

Results A total of 1671 patients were enrolled, 70.7% women, with median age of 40 years. The prevalence of intermittent, mild persistent, moderate persistent and severe persistent asthma was 2.9%, 19.9%, 42.6% and 34.6%, respectively. Only 14% were on inhaled corticosteroids (ICS). Patients with severe persistent asthma had a higher rate of adult onset asthma, smoking, HIV, history of TB, FeNO and absolute eosinophil count but lower rates of GERD, rhinosinusitis and SPT positivity. In the multivariate model, Ethiopian site and a history of GERD remained associated with asthma severity.

Discussion The majority of patients in this cohort presented with moderate to severe persistent asthma and the use of ICS was very low. Improving access to ICS and other inhaled therapies could greatly reduce asthma morbidity in Africa.

  • asthma
  • asthma mechanisms
  • asthma epidemiology

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  • Contributors BK conceived the initial idea of the ASAP project and BK, TvdM, JC, GY, MK, MJ and CdJ designed the study. WM, WW, HA-T, WK, GN, GY, JC, AB, TH and BK participated in data acquisition. CdJ coordinated data quality control. BK wrote the original draft of the manuscript. BK, NL, FM, CG and LM conducted the data analysis. All authors contributed to the drafting and finalisation of the manuscript.

  • Funding The study was funded by a project grant from the GSK Africa Non-Communicable Disease Open Lab (Project number: 8019). The funder provided in-kind scientific and statistical support in the study design but had no role in data collection, analysis or decision to publish. Authors retained control of the final content of the publication.

  • Competing interests None declared.

  • Patient consent for publication Not required.

  • Ethics approval Overall ethics approval was obtained from the Mulago Hospital research and ethics committee (MHREC 875). and from local ethics committees in each country.

  • Provenance and peer review Not commissioned; externally peer reviewed.

  • Data availability statement Data are available upon reasonable request. Data used in this manuscript is available in hard paper copy and soft copy data files at Makerere University Lung Institute and each participating institution.

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