Between 2007 and 2017, an increase of 15.6% in the prevalence of COPD was reported.³  Savi et al refers to COPD as the silent epidemic of Africa because the prevalence of COPD in sub-Saharan Africa has been poorly studied as a result of a lack of standardised epidemiological instruments and the need to do good quality post-bronchodilator spirometry, which requires considerable expertise and experience.¹

According to a 2022 study by Awokola et al, the prevalence of COPD in urban areas in South Africa is as high as 24.8% compared to a global prevalence of 11.8%.²

Cape Town had the highest prevalence of stage ≥2 COPD (19% overall, 22% male and 17% female), because of the higher incidence of smoking, occupational dust exposure, indoor pollution, and prior tuberculosis (TB).³

COPD is often unrecognised by patients and physicians and therefore underdiagnosed and undertreated, especially in many Sub-Saharan Africa settings, where attention remains more focused on communicable diseases.²

Risk factors and symptoms

Risk factors for COPD include:^4,5

• Smoking (compared to smokers, never smokers with airflow limitations have fewer symptoms, milder disease, and less systemic inflammation)
• Genetics (severe hereditary deficiency of aslpha1-antitrypsin)
• Infections (severe childhood respiratory infections)
• Ageing and gender (ageing of the airways and parenchyma mimic some of the structural changes associated with COPD, women are more affected by the damage caused by smoking leading to more severe disease, but men are at higher risk of mortality due to COPD)
• Retarded lung growth during gestation and childhood
• Occupational exposures (organic and inorganic dust, chemical agents, and fumes)
• Indoor (wood, animal dung, crop residues and coal used for cooking or heat) and outdoor air pollutants (causal effect is unclear)
• Chronic bronchitis
• Asthma
• Low socioeconomic status.

According to the 2022 Global Initiative for Chronic Obstructive Lung Disease (GOLD) guideline, COPD is characterised by persistent respiratory symptoms and airflow limitations that is due to airway and/or alveolar abnormalities.⁵

Clinical manifestations of COPD include: a chronic cough or sputum production (30% of patients), dyspnoea (increased effort to breath, chest heaviness, air hunger or gasping), wheezing and chest tightness. Symptoms are often more severe in the early morning and evening but may increase during the day as the disease progresses.^4,5

Systemic features of COPD include muscle wasting and cachexia, which may lead to worsening of comorbid conditions such as cardiovascular disease, asthma, osteoporosis, and diabetes.⁵

Diagnosis

According to authors of the South African Thoracic Society position paper (2019) COPD is either undiagnosed or diagnosed too late, thus limiting the benefit of therapeutic interventions.³

The diagnosis of COPD should be considered in any patient with chronic progressive dyspnoea and/or chronic cough (with or without sputum production) with a smoking history of more than 10 pack-years and/or other risk factors for COPD.³

A detailed history of exposure during childhood, occupation, as well as tobacco, HIV and previous TB is important. All smokers should be considered at risk and have screening spirometry where this is available.³

The authors recommend performing spirometry in at-risk individuals, which will help to identify COPD early. Correct diagnosis, and in particular the differentiation of COPD from other causes of patient’s symptoms, is important to ensure correct treatment.³

Treatment

According to the new GOLD guideline, the objectives of treatment are two-fold:⁵

• Relieving and reducing the impact of symptoms
• Reducing the risk of adverse health events such as exacerbations.

COPD is generally managed with inhaled pharmacotherapy, as well as smoking cessation, pulmonary rehabilitation, vaccination, and oxygen therapy in advanced cases.⁵

Best practice guidelines recommend that:⁶

• The cornerstone of treatment is bronchodilators (BD) with the possibility that inhaled corticosteroids (ICS) will never be included in the life course
• Treatment with ICS should be avoided as the inflammation present in the pathology of COPD is ICS-resistant. They are associated with the development of pneumonia
• Only when the disease is severe and/or an associated eosinophil phenotype, then ICS may be utilised
• If the patient is stable on an ICS–bronchodilator regimen, then the ICS must be withdrawn.

However, Irusen and Malange (2020) argue that anti-inflammatory medication should be the mainstay of COPD treatment. Currently, they state, ICS are the best agents available.⁶

The hesitancy in prescribing ICS because of the possibility of adverse metabolic effects and pneumonia (over 90% of COPD patients in all clinical trials do not get pneumonia) - although important - is unwarranted, they stress. When confounders for these occurrences have been considered, the risks appear negligible or of very low frequency at worst.⁶

The data also show that ICS withdrawal is deleterious and ill-advised in a disease with a natural history of progressive decline necessitating increased pharmaceutical support. Those patients with more eosinophils should be targeted for early ICS therapy, and de-escalation should not be contemplated for them, they write.⁶

When the disease has progressed beyond the mild stage, dual BD and ICS, ideally in a single inhaler, are a compelling option for optimal therapeutic outcomes.⁶

COPD has a considerable impact on respiratory reserve and is associated with increasing morbidity. Optimal outcomes are best achieved with long-acting bronchodilators and ICS co-prescription, they conclude.⁶

Survival rates

The prognosis of COPD is determined by measuring forced expiratory volume in one second, a measure of airflow. Moreover, COPD can affect the prognosis of other diseases, such as covid-19, cancer, mental health conditions, cardiovascular diseases, gastrointestinal disorders, and musculoskeletal disorders.⁴

A recent 13-year follow-up study (n=37 930) conducted in Brazil Patient's survival rates at one and 10 years were 97.6% and 83.1%, respectively. The multivariate analysis showed that male patients, >65-years and underweight had an increased risk of mortality.⁷

Therapeutic regimens containing a BD in a free dose along with a fixed-dose combination of ICS and BD seem to be a protective factor when compared to other regimens.⁷

GOLD key messages⁵

• Smoking cessation is key
• Pharmacological therapy can reduce COPD symptoms, reduce the frequency and severity of exacerbations, improve overall health status and reduce the risk of mortality
• Each pharmacological treatment regimen should be individualised and guided by the severity of symptoms, risk of exacerbations, side-effects, comorbidities, available drugs and cost, and the patient’s response to treatment, his/her preference and ability to use delivery devices
• Inhaler techniques need to be assessed regularly
• Patients with COPD should be vaccinated against Covid-19
• Influenza and pneumococcal vaccines decrease the risk of lower respiratory tract infections
• Pulmonary rehabilitation improves symptoms, quality of life across all grades of COPD
• In patients with severe resting chronic hypoxemia, long-term oxygen therapy improves survival
• In patients with stable COPD and resting or exercise-induced moderate desaturation, long-term oxygen therapy should not be prescribed routinely. However, individual patient factors must be considered when evaluating the patient’s need for supplemental oxygen
• In patients with severe chronic hypercapnia and a history of hospitalisation for acute respiratory failure, long-term, non-invasive ventilation may decrease mortality and prevent rehospitalisation
• In select patients with advanced emphysema refractory to optimised medical care, surgical or bronchoscopic interventional treatments may be beneficial
• Palliative approaches are effective in controlling symptoms in advanced COPD.

REFERENCES:

1. Salvi S. The silent epidemic of COPD in Africa. The Lancet Global Health, 2015.
2. Safiri S, Carson-Chahhoud, Noori M, et al. Burden of chronic obstructive pulmonary disease and its attributable risk factors in 204 countries and territories, 1990-2019: results from the Global Burden of Disease Study 2019. BMJ,2022.
3. Abdool-Gaffar MS, Calligaro G, van Zyl RN, et al. Management of chronic obstructive pulmonary disease—A position statement of the South African Thoracic Society: 2019 update. Journal of Thoracic Disease, 2019.
4. Awokola BI, Amusa GA, Mortimer KJ, et al. Chronic obstructive pulmonary disease in sub-Saharan Africa. The International Journal of Tuberculosis and Lung Disease,
5. Global strategy for Prevention, Diagnosis and Management of COPD: 2022 report.https://goldcopd.org/2022-gold-reports-2/
6. Irusen EM, Malange TD. Pharmacotherapy of chronic obstructive pulmonary disease: Therapeutic considerations with a focus on inhaled corticosteroids. South African Family Practice, 2020.
7. Gargano LP, Zuppo IDF, Nascimento MMGD, et al. Survival Analysis of COPD Patients in a 13-Year Nationwide Cohort Study of the Brazilian National Health System. Frontiers in Big Data, 2020.