The goal of this observational study is to evaluate the frequency and predictors of exacerbations in COPD patient population in Uganda.

The main questions it aims to answer are:-

1. What is the proportion of frequent exacerbators (≥2/year) and what factors are associated with the frequent exacerbator phenotype?
2. What is the frequency of exacerbations and what factors are correlated with exacerbation frequency? Participants will be asked to offer demographic ,clinical and exposure questions. Questionnaires assessing disease burden, and quality of life will be administered. Clinical measurements, and complete blood count will be collected ta baseline and on sick visits. Spirometry will be measured at baseline and on the last visit. Samples will be collected for storage. Participants will be followed up for one year.

In this prospective observational study aimed at evaluating the frequency and predictors of exacerbations in a COPD population, the following were the objectives.

Primary objective

1. To estimate the proportion and predictors of frequent COPD exacerbations in Ugandans with COPD. Secondary objective(s)

1. To determine the frequency and predictors of exacerbations among COPD patients in Uganda
2. To evaluate the aetiologies of COPD exacerbations including eosinophilia, and bacterial causes.
3. To evaluate outcomes such as quality of life, lung function decline in patients with exacerbations by frequency of the exacerbations. COPD will be diagnosed as follows Definitions and diagnostic criteria for COPD and its grading, and that of an exacerbation have been provided by the GOLD guidelines 4 . This study will use the GOLD definitions and classifications. As per GOLD 2018 guidelines 4 , COPD will be considered in any patient with appropriate spirometry who has dyspnea, chronic cough or sputum production, and/or a history of exposure to risk factors for the disease.

GOLD 2018 definition of an exacerbation:

An acute worsening in respiratory symptoms that results in additional therapy. A) Mild exacerbation: Requires additional treatment with short acting bronchodilators only B) Moderate exacerbation: Requires additional treatment with short acting bronchodilators plus antibiotics and / or oral corticosteroids C) Severe exacerbation: Requires hospitalization or visit to emergency room. participants will be followed up at three monthly intervals, except when they have had a severe exacerbation, where they will be followed up at two weekly intervals until they stabilise.

During the follow up visit, participant's COPD diaries will be evaluated for exacerbation length, severity and frequency as well as health care utilization. Additionally the CAT, CCQ and MRC dyspnoea scale questionaires, to evaluate the impact of COPD on quality of life will be administered. Finally lung function will be evaluated by spirometry.

Inclusion Criteria:

• Age ≥30yrs
• COPD diagnosis as per protocol (page 7)
• Attending URAC clinic sites
• Written informed consent
• Able to fill in diary or has attendant who can help fill it out
• Willing to attend follow up visits as required by study

Exclusion Criteria:

• Active pulmonary tuberculosis
• Other important co-morbid disease likely to affect participation or outcomes, such as lung cancer, asthma and any other that may be deemed so, in which case be discussed on case by case basis by the investigational team.

We will recruit COPD patients aged ≥ 30, diagnosed as specified on page 7. These patients will be identified during the screening phase as having GOLD airflow obstruction severity grades 1-4 and symptom/exacerbation risk categories A-D per the GOLD 2018 criteria (Figure 1). The cut-off of 30 years was chosen because prevalence studies in Ugandans indicated that COPD was prevalent in those as young as 30 years 18 .