Prognostic Factors for Deterioration in Health Status, Functional Capacity, and Physical Activity, and for the Occurrence of Exacerbations in the Spanish Activity Questionnaire in Chronic Obstructive Pulmonary Disease (SAQ-COPD) Cohort of COPD Patients

Chronic obstructive pulmonary disease (COPD), which includes long-term breathing problems like chronic bronchitis and emphysema, is a major health condition that makes it difficult for people to breathe. It affects hundreds of millions of people worldwide and is one of the leading causes of illness and death. People with COPD often cope with other health problems at the same time (called comorbidities), experience decreased ability to move and exercise and are at high risk for flare-ups (called exacerbations) that often lead to emergency care or hospital visits. These issues reduce quality of life and increase the need for medical services.

We will study a group of people with COPD who are part of the SAQ-COPD (Spanish Activity Questionnaire–Chronic Obstructive Pulmonary Disease) cohort. Our goal is to understand whether information collected at the beginning of the study—such as age, sex, medical history, fitness levels, and physical activity—can help us predict which patients are most likely to experience worsening health. We will focus on several outcomes, including changes in symptoms, use of healthcare services, physical activity levels, and the number of exacerbations.

We will also look at whether physical activity and functional capacity (a person’s ability to carry out daily tasks) are linked with each other and with overall health at the start of the study. To answer our research questions, we will conduct a secondary analysis of data that has already been collected from participants over six months. We will compare their initial (baseline) measurements with results collected at the six-month follow-up. We will then use statistical models to identify which baseline factors best predict worsening health, lower physical activity, or more frequent flare-ups. Our aim is to determine early warning signs that could help healthcare providers identify patients who need closer monitoring or earlier intervention.

This research is important because COPD is a lifelong disease, and being able to predict who is most at risk of decline could improve care and reduce hospital visits. If we are able to find simple and reliable predictors—such as low physical activity or poor performance on the Five Sit-to-Stand (5-STS) test—healthcare teams could use this information to guide treatment decisions and create more personalized care plans. In the long term, we hope this work will help improve the quality of life and prognosis for people living with COPD.