RETRO-POPE: A Retrospective, Multicenter, Real-World Study of All-Cause Mortality in COPD

Purpose

The Phenotypes of COPD in Central and Eastern Europe (POPE) study assessed the prevalence and clinical characteristics of four clinical COPD phenotypes, but not mortality. This retrospective analysis of the POPE study (RETRO-POPE) investigated the relationship between all-cause mortality and patient characteristics using two grouping methods: clinical phenotyping (as in POPE) and Burgel clustering, to better identify high-risk patients.

Patients and Methods

The two largest POPE study patient cohorts (Czech Republic and Serbia) were categorized into one of four clinical phenotypes (acute exacerbators [with/without chronic bronchitis], non-exacerbators, asthma-COPD overlap), and one of five Burgel clusters based on comorbidities, lung function, age, body mass index (BMI) and dyspnea (very severe comorbid, very severe respiratory, moderate-to-severe respiratory, moderate-to-severe comorbid/obese, and mild respiratory). Patients were followed-up for approximately 7 years for survival status.

Results

Overall, 801 of 1,003 screened patients had sufficient data for analysis. Of these, 440 patients (54.9%) were alive and 361 (45.1%) had died at the end of follow-up. Analysis of survival by clinical phenotype showed no significant differences between the phenotypes (P=0.211). However, Burgel clustering demonstrated significant differences in survival between clusters (P<0.001), with patients in the "very severe comorbid" and "very severe respiratory" clusters most likely to die. Overall survival was not significantly different between Serbia and the Czech Republic after adjustment for age, BMI, comorbidities and forced expiratory volume in 1 second (hazard ratio [HR] 0.80, 95% confidence interval [CI] 0.65-0.99; P=0.036 [unadjusted]; HR 0.88, 95% CI 0.7-1.1; P=0.257 [adjusted]). The most common causes of death were respiratory-related (36.8%), followed by cardiovascular (25.2%) then neoplasm (15.2%).

Conclusion

Patient clusters based on comorbidities, lung function, age, BMI and dyspnea were more likely to show differences in COPD mortality risk than phenotypes defined by exacerbation history and presence/absence of chronic bronchitis and/or asthmatic features.

Measurements of tissue polypeptide-specific antigen and prostate-specific antigen in prostate cancer patients under intermittent androgen suppression therapy

The present study evaluated serial serum measurements of tissue polypeptide-specific antigen (TPS) in comparison with prostate-specific antigen (PSA) for assessment of tumour progression in patients with advanced prostate cancer receiving intermittent androgen suppression therapy (IAS). Twenty-three men were recruited into an IAS trial consisting of an initial 8 months of androgen suppression, followed by cycles of treatment cessation and resumption of therapy upon increases of PSA > 20 ng ml(-1) to prolong the hormone responsiveness of the tumour cells. Periods of androgen suppression resulted in reversible reduction in serum testosterone (< 1.8 nmol I(-1)) and PSA (< 4 ng ml(-1)) and decreases in tumour volume (mean reduction for first cycle 24 +/- 10%), indicating partial growth arrest and apoptotic regression of the tumours. In contrast to PSA values, non-specifically elevated TPS values were found in 8 of 23 patients. In 15 of 23 patients, TPS fell during periods of apoptotic tumour regression and increased simultaneously with testosterone and preceded the increases in PSA by 2 months during the period of treatment cessation. Although TPS represents a highly sensitive marker of tumour proliferation in this IAS clinical model of controlled tumour regression and regrowth, its low specificity compared with PSA limits its usefulness to monitoring of prostate cancer patients with proven absence of non-specific elevations of this marker.