Factors associated with changes in quality of life of COPD patients: a prospective study in primary care.

Background: A primary objective in the treatment of patients with chronic obstructive pulmonary disease (COPD) is to improve their health status.

Objective: To identify the factors associated with changes in health-related quality of life (HRQoL) in patients with COPD after one year of follow-up in primary care.

Method: Multicenter, prospective study with one year of follow-up. The end-point was the change in total score on the Saint George's Respiratory Questionnaire (SGRQ). Patients with a clinically relevant (>4 points) decrease or increase in SGRQ total score were compared. Factors associated with the changes in HRQoL observed after one year were determined by logistic regression analysis.

Results: A total of 791 patients (mean age, 70.2 years) were analyzed. Mean FEV1 (% predicted) was 52.4%. Average total SGQR score was 37.1 (SD = 19.1) at baseline and 35.6 (SD = 18.9) at follow-up. Significantly improved HRQoL was observed in 36.7% of patients, and was associated with starting polymedication, pulmonology visits, and balanced diet; ending respiratory rehabilitation, quitting smoking; and not being a frequent exacerbator. Quality of life worsened significantly in 29.2% of patients, and was associated with worsening respiratory symptoms and increased hospital admissions.

Conclusions: Although overall changes in HRQoL observed after one year were minimal, more than one third of patients improved significantly, and one third had significantly worse HRQoL. Clinical factors were independently associated with these changes, emphasizing the relevance to improved HRQoL of starting a healthy lifestyle and respiratory treatments and the negative impact on HRQoL of COPD symptoms onset and admissions.