Stability of distinct symptom experiences in patients with chronic obstructive pulmonary disease (COPD).

PURPOSE: This study aimed to examine reclassification rates among classes of chronic obstructive pulmonary disease (COPD) patients based on their distinct symptom experiences and to assess how these subgroups differed in symptom scores and health-related quality of life (HRQoL) outcomes over one year. Moreover, we wished to assess how these subgroups differed in demographic and clinical characteristics at 12 months. PATIENTS AND METHODS: This is a follow-up study of 267 patients with moderate, severe, and very severe COPD. Based on their distinct symptom experiences using the Memorial Symptom Assessment Scale (MSAS), three subgroups (i.e., "high", "intermediate", and "low") were identified at baseline. In the present study, transitions between the subgroups at three, six, nine, and 12 months were investigated and calculated as reclassification rates. Differences among the subgroups in symptom scores and HRQoL at each time point and demographic and clinical characteristics at 12 months were evaluated using analysis of variance with post hoc comparisons. RESULTS: Almost 65% were still in the "high" class after 12 months. At 12 months, pairwise comparisons for respiratory function measurements were not significantly different. Compared to the "intermediate" and "low" class, patients in the "high" class were more likely to be women and had significantly more comorbidities, reported a significantly higher number of symptoms at all time points, and worse HRQoL scores. CONCLUSION: Our findings suggest that the pattern of a high symptom burden in COPD is consistent over time. The patients' individual symptom experiences should be the primary focus of treatment.

Changes in and predictors of pain and mortality in patients with chronic obstructive pulmonary disease.

This longitudinal study of patients with chronic obstructive pulmonary disease (COPD) aimed to investigate changes in pain characteristics (i.e., occurrence, intensity, and interference) and covariates associated with pain from study enrollment to 12 months, and to investigate if the different pain characteristics were associated with 5-year mortality. In total, 267 patients with COPD completed questionnaires five times over 1 year. The mean age of the patients was 63 years (standard deviation: 9.0), 53% were women, and 46% had very severe COPD. Median number of comorbidities was 2.0 (range: 0-11) and 47% of patients reported back/neck pain. Mixed models and Cox regression models were used for analyses. In total, 60% of the patients reported pain at baseline, and 61% at 12 months. The mixed model analyses revealed that those with better forced expiratory volume in 1 s (% predicted), more comorbidities, only primary school education, and more respiratory symptoms reported significantly higher average pain intensity. Moreover, those with more comorbidities, more respiratory symptoms, and more depression reported higher pain interference with function. At the 5-year follow-up, 64 patients (24%) were deceased, and the cumulative 5-year mortality rate was 22% (95% confidence interval [19-25]). Older age, lower forced expiratory volume in 1 s (% predicted), and higher pain interference at enrollment were all independently and significantly associated with higher 5-year mortality. Our findings show that many patients with COPD have persistent pain, and awareness regarding comorbidities and how pain interferes with their lives is needed.

Distinct pain profiles in patients with chronic obstructive pulmonary disease.

Background: Few studies have examined changes in the pain experience of patients with COPD and predictors of pain in these patients. Objectives: The objectives of the study were to examine whether distinct groups of COPD patients could be identified based on changes in the occurrence and severity of pain over 12 months and to evaluate whether these groups differed on demographic, clinical, and pain characteristics, and health-related quality of life (HRQoL). Patients and methods: A longitudinal study of 267 COPD patients with very severe COPD was conducted. Their mean age was 63 years, and 53% were females. The patients completed questionnaires including demographic and clinical variables, the Brief Pain Inventory, and the St Georges Respiratory Questionnaire at enrollment, and 3, 6, 9, and 12 months follow-up. In addition, spirometry and the 6 Minute Walk Test were performed. Latent class analysis was used to identify subgroups of patients with distinct pain profiles based on pain occurrence and worst pain severity. Results: Most of the patients (77%) reported pain occurrence over 12 months. Of these, 48% were in the "high probability of pain" group, while 29% were in the "moderate probability of pain" group. For the worst pain severity, 37% were in the "moderate pain" and 39% were in the "mild pain" groups. Females and those with higher body mass index, higher number of comorbidities, and less education were in the pain groups. Patients in the higher pain groups reported higher pain interference scores, higher number of pain locations, and more respiratory symptoms. Few differences in HRQoL were found between the groups except for the symptom subscale. Conclusion: Patients with COPD warrant comprehensive pain management. Clinicians may use this information to identify those who are at higher risk for persistent pain.

Distinct symptom experiences in subgroups of patients with COPD.

BACKGROUND: In addition to their respiratory symptoms, patients with COPD experience multiple, co-occurring symptoms. OBJECTIVES: The aims of this study were to identify subgroups of COPD patients based on their distinct experiences with 14 symptoms and to determine how these subgroups differed in demographic and clinical characteristics and disease-specific quality of life. PATIENTS AND METHODS: Patients with moderate, severe, and very severe COPD (n=267) completed a number of self-report questionnaires. Latent class analysis was used to identify subgroups of patients with distinct symptom experiences based on the occurrence of self-reported symptoms using the Memorial Symptom Assessment Scale. RESULTS: Based on the probability of occurrence of a number of physical and psychological symptoms, three subgroups of patients (ie, latent classes) were identified and named "high", "intermediate", and "low". Across the three latent classes, the pairwise comparisons for the classification of airflow limitation in COPD were not significantly different, which suggests that measurements of respiratory function are not associated with COPD patients' symptom burden and their specific needs for symptom management. While patients in both the "high" and "intermediate" classes had high occurrence rates for respiratory symptoms, patients in the "high" class had the highest occurrence rates for psychological symptoms. Compared with the "intermediate" class, patients in the "high" class were younger, more likely to be women, had significantly more acute exacerbations in the past year, and reported significantly worse disease-specific quality of life scores. CONCLUSION: These findings suggest that subgroups of COPD patients with distinct symptom experiences can be identified. Patients with a higher symptom burden warrant more detailed assessments and may have therapeutic needs that would not be identified using current classifications based only on respiratory function.