Purpose
How changes in depression and anxiety and well-being may fluctuate with changes in disease-specific quality of life (QOL), and further how changes in well-being may fluctuate with changes in depression and anxiety among patients with moderate and severe chronic obstructive pulmonary disease (COPD).
Methods
In a longitudinal study (as part of a randomized controlled trial), we investigated 150 patients with moderate and severe COPD at baseline, 143 at 4 weeks, and 130 at 4 months. Lung function was tested, and a questionnaire was completed at all appointments. The questions captured demographic variables, disease-specific QOL (St. George’s Respiratory Questionnaire), anxiety and depression (Hospital Anxiety and Depression Scale), and well-being (World Health Organization-5 Well-being Index). Multiple regression analyses were performed.
Results
At 4 weeks and 4 months, changes in disease-specific QOL (st. β = –0.35, p < 0.001, partial (p) R
2 = 11–12 %), depression (st. β = –0.32 to –0.36, p < 0.001, pR
2 = 9–12 %), and anxiety (st. β = –0.21 to –0.40, p < 0.02–0.001, pR
2 = 4–15 %) were significantly associated with changes in well-being. Changes in disease-specific QOL were significantly associated with changes in anxiety at 4 months (st. β = 0.21, p = 0.02, pR
2 = 4 %), but not with changes in depression.
Conclusions
Changes in disease-specific QOL, depression, and anxiety were associated with changes in well-being. Changes in disease-specific QOL contributed slightly to changes in anxiety, but not to changes in depression. Well-being may capture some aspects of mental QOL in COPD patients better than depression and anxiety.