The burden of severe asthma in sub-Saharan Africa: Findings from the African Severe Asthma Project

Bruce J Kirenga; Jeremiah Chakaya; Getnet Yimer; George Nyale; Tewodros Haile; Winters Muttamba; Levicatus Mugenyi; Winceslaus Katagira; William Worodria; Hellen Aanyu-Tukamuhebwa; Njira Lugogo; Moses Joloba; Tesfaye B Mersha; Amsalu Bekele; Fred Makumbi; Amha Mekasha; Cynthia L Green; Corina de Jong; Moses Kamya; Thys van der Molen

doi:10.1016/j.jacig.2024.100209

The burden of severe asthma in sub-Saharan Africa: Findings from the African Severe Asthma Project

J Allergy Clin Immunol Glob. 2024 Jan 9;3(2):100209. doi: 10.1016/j.jacig.2024.100209. eCollection 2024 May.

Authors

Bruce J Kirenga^{1

2}, Jeremiah Chakaya³, Getnet Yimer⁴, George Nyale^{3

5}, Tewodros Haile⁴, Winters Muttamba^{1

6}, Levicatus Mugenyi^{1

7}, Winceslaus Katagira¹, William Worodria⁸, Hellen Aanyu-Tukamuhebwa⁸, Njira Lugogo⁹, Moses Joloba¹⁰, Tesfaye B Mersha¹¹, Amsalu Bekele⁴, Fred Makumbi¹², Amha Mekasha⁴, Cynthia L Green¹³, Corina de Jong¹⁴, Moses Kamya², Thys van der Molen¹⁴

Affiliations

¹ Makerere University Lung Institute, Kampala, Uganda.
² Department of Medicine, Makerere University, Kampala, Uganda.
³ Kenya Association of Physicians Against TB and Lung Diseases, Nairobi, Kenya.
⁴ Addis Ababa University College of Health Sciences, Addis Ababa, Ethiopia.
⁵ Kenyatta National Hospital, Nairobi, Kenya.
⁶ Division of Infection and Global Health, School of Medicine, University of St Andrews, St Andrews, United Kingdom.
⁷ Medical Research Council/Uganda Virus Research Institute and London School of Hygiene and Tropical Medicine Research Unit, Entebbe, Uganda.
⁸ Mulago Hospital, Kampala, Uganda.
⁹ Department of Internal Medicine, Division of Pulmonary and Critical Care Medicine, University of Michigan, Ann Arbor, Mich.
¹⁰ Department of Medical Microbiology, Makerere University, Kampala, Uganda.
¹¹ Division of Asthma Research, Department of Pediatrics, Cincinnati Children's Hospital Medical Center, University of Cincinnati College of Medicine, Cincinnati, Ohio.
¹² School of Public Health, Makerere University, Kampala, Uganda.
¹³ Department of Biostatistics and Bioinformatics, Duke University School of Medicine, Durham, NC.
¹⁴ Department of General Practice and Elderly Care, GRIAC-Primary Care, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands.

Abstract

Background: Severe asthma is associated with high morbidity, mortality, and health care utilization, but its burden in Africa is unknown.

Objective: We sought to determine the burden (prevalence, mortality, and activity and work impairment) of severe asthma in 3 countries in East Africa: Uganda, Kenya, and Ethiopia.

Methods: Using the American Thoracic Society/European Respiratory Society case definition of severe asthma, we analyzed for the prevalence of severe asthma (requiring Global Initiative for Asthma [GINA] steps 4-5 asthma medications for the previous year to achieve control) and severe refractory asthma (remains uncontrolled despite treatment with GINA steps 4-5 asthma medications) in a cohort of 1086 asthma patients who had been in care for 12 months and had received all GINA-recommended medications. Asthma control was assessed by the asthma control questionnaire (ACQ).

Results: Overall, the prevalence of severe asthma and severe refractory asthma was 25.6% (95% confidence interval [CI], 23.1-28.3) and 4.6% (95% CI, 3.5-6.0), respectively. Patients with severe asthma were (nonsevere vs severe vs severe refractory) older (39, 42, 45 years, P = .011), had high skin prick test reactivity (67.1%, 76.0%, 76.0%, P = .004), had lower forced expiratory volume in 1 second percentage (81%, 61%, 55.5%, P < .001), had lower quality of life score (129, 127 vs 121, P < .001), and had higher activity impairment (10%, 30%, 50%, P < .001). Factors independently associated with severe asthma were hypertension comorbidity; adjusted odds ratio 2.21 (1.10-4.47), P = .027, high bronchial hyperresponsiveness questionnaire score; adjusted odds ratio 2.16 (1.01-4.61), P = .047 and higher ACQ score at baseline 2.80 (1.55-5.08), P = .001.

Conclusion: The prevalence of severe asthma in Africa is high and is associated with high morbidity and poor quality of life.

Keywords: Severe asthma; burden of severe asthma; severe asthma determinants; sub-Saharan Africa.