Chronic obstructive pulmonary disease phenotypes in Turkey: the COPET study-a national, multicenter cross-sectional observational study.

BACKGROUND: While mortality rates decrease in many chronic diseases, it continues to increase in COPD. This situation has led to the need to develop new approaches such as phenotypes in the management of COPD. We aimed to investigate the distribution, characteristics and treatment preference of COPD phenotypes in Turkey. METHODS: The study was designed as a national, multicenter, observational and cross-sectional. A total of 1141 stable COPD patients were included in the analysis. RESULTS: The phenotype distribution was as follows: 55.7% nonexacerbators (NON-AE), 25.6% frequent exacerbators without chronic bronchitis (AE NON-CB), 13.9% frequent exacerbators with chronic bronchitis (AE-CB), and 4.8% with asthma and COPD overlap (ACO). The FEV1 values were significantly higher in the ACO and NON-AE than in the AE-CB and AE NON-CB (p < 0.001). The symptom scores, ADO (age, dyspnoea and FEV1 ) index and the rates of exacerbations were significantly higher in the AE-CB and AE NON-CB phenotypes than in the ACO and NON-AE phenotypes (p < 0.001). Treatment preference in patients with COPD was statistically different among the phenotypes (p < 0.001). Subgroup analysis was performed in terms of emphysema, chronic bronchitis and ACO phenotypes of 1107 patients who had thoracic computed tomography. A total of 202 patients had more than one phenotypic trait, and 149 patients showed no features of a specific phenotype. DISCUSSION: Most of the phenotype models have tried to classify the patient into a certain phenotype so far. However, we observed that some of the patients with COPD had two or more phenotypes together. Therefore, rather than determining which phenotype the patients are classified in, searching for the phenotypic traits of each patient may enable more effective and individualized treatment.

Associations between respiratory health and ambient air quality in Canakkale, Turkey: a long-term cohort study.

Few epidemiological studies investigating the association between air pollution and health are available in Turkey. The aim of this cohort-type study is to examine the relationships between ambient air quality, respiratory diseases, and decreases in pulmonary function over a year in three different towns in Canakkale: Canakkale Central town (region I), Lapseki town center (region II), and Can town (region III). Region III had four different sub-regions, which were Can town center (region III-A), and the villages located around Can town, namely Durali (region III-B), Kulfal (region III-C), and Yuvalar (region III-D). In the first stage of the study, a detailed questionnaire was completed by the participants (n = 1152) in face-to-face interviews and pulmonary function test (PFT) was performed. In the second stage of the study, PFT measurements were repeated 1 year after the first stage. Particulate matter, SO2, NO2, and ozone were gathered from air quality monitoring stations located in the centers of the three regions. The most polluted area was region III, while region I and region II were the least polluted areas. The risk of pulmonary function decline throughout a year was 2.1 times higher in region III, 2.4 times higher both in regions III-B and III-C, and 1.6 times higher for smokers in all regions. In the present study, ambient air quality was worse in region III (industrialized region), which influenced PFT scores and the prognostics for chronic respiratory diseases. The findings of this study should be considered for future investment plans in this region related to human and environmental health needs.