RESEARCH QUESTION: We aim to determine if clusters of Chinese patients with COPD exist and their association with clinical outcomes and inflammation.
STUDY DESIGN AND METHODS: Chinese patients with stable COPD were prospectively recruited into two cohorts (derivation and validation) from six hospitals across three Southeast Asian countries (Singapore, Malaysia, and Hong Kong; n = 1,480). Each patient was followed more than 2 years. Clinical data (including co-morbidities) were employed in unsupervised hierarchical clustering (followed by validation) to determine the existence of patient clusters and their prognostic outcome. Accompanying systemic cytokine assessments were performed in a subset (n = 336) of patients with COPD to determine if inflammatory patterns and associated networks characterized the derived clusters.
RESULTS: Five patient clusters were identified including: (1) ex-TB, (2) diabetic, (3) low comorbidity: low-risk, (4) low comorbidity: high-risk, and (5) cardiovascular. The cardiovascular and ex-TB clusters demonstrate highest mortality (independent of Global Initiative for Chronic Obstructive Lung Disease assessment) and illustrate diverse cytokine patterns with complex inflammatory networks.
INTERPRETATION: We describe clusters of Chinese patients with COPD, two of which represent high-risk clusters. The cardiovascular and ex-TB patient clusters exhibit high mortality, significant inflammation, and complex cytokine networks. Clinical and inflammatory risk stratification of Chinese patients with COPD should be considered for targeted intervention to improve disease outcomes.
METHODS: A multi-center retrospective study design was used to collect data from TB patients in four different states of Malaysia, namely Penang, Sabah, Sarawak, and Selangor. The study included medical records of TB patients admitted to the selected hospitals in the period from January 2006 to March 2009. Medical records with incomplete data were not included. Patient demographics and clinical data were collected using a validated data collection form.
RESULTS: Of all patients with TB (9337), the prevalence of smokers was 4313 (46.2%). Among smokers, 3584 (83.1%) were associated with pulmonary TB, while 729 (16.9%) were associated with extrapulmonary TB. Male gender (OR = 1.43, 95% CI 1.30-1.58), Chinese ethnicity (OR = 1.23, 95% CI 1.02-1.49), Sarawak indigenous ethnicity (OR = 0.74, 95% CI 0.58-0.95), urban residents (OR = 1.46, 95% CI 1.33-1.61), employed individuals (OR = 1.21, 95% CI 1.09-1.34), alcoholics (OR = 4.91, 95% CI 4.04-5.96), drug abusers (OR = 7.43, 95% CI 5.70-9.60) and presence of co-morbid condition (OR = 1.27, 95% CI 1.16-1.40) all showed significant association with smoking habits. This study found that 3236 (75.0%) patients were successfully treated in the smokers' group, while 4004 (79.7%) patients were non-smokers. The proportion of deaths (6.6%, n = 283), defaulters (6.6%, n = 284) and treatment interruptions (4.7%, n = 204) was higher in the smokers' group.
CONCLUSIONS: Smoking has a strong influence on TB and is a major barrier towards treatment success (OR = 0.76, 95% CI 0.69-0.84, p