BACKGROUND: @entity2544 has been shown to improve respiratory function and oxygenation in @entity1 with @entity1030 ( @entity1030 ). However, the impact of @entity2544 on mortality in @entity1030 @entity1 has not been not sufficiently evaluated. METHOD: Two investigators independently searched for eligible articles in 4 databases. The eligibility criterion for this meta-analysis was an original research article that provided a hazard ratio for @entity2544 for all-cause mortality of @entity1030 @entity1 . Both randomized controlled trials and observational studies were accepted. After we confirmed no substantial heterogeneity (I(2)<50%), the fixed-model method with generic inverse variance was used for meta-analysis to estimate the pooled hazard ratio. RESULTS: We screened 364 potentially eligible articles. Of the 364 articles, 259 were excluded on the basis of title and abstract, and 99 were excluded after examination of the full text. Our final analysis included 6 observational studies and no randomized controlled trials. One study reported 2 cohorts. The number of @entity1 in each cohort ranged from 47 to 46,403. Heterogeneity (I(2)=42%, @entity1354 ) and publication bias (Begg's test r=0.21, P=.662) were not substantial. Fixed-model meta-analysis yielded a pooled hazard ratio for @entity2544 for all-cause @entity204 of 1.07 (95% confidence interval: 1.02-1.13, P=.003). CONCLUSION: This meta-analysis of 7 observational cohorts suggests that @entity2544 slightly increases all-cause @entity204 in @entity1030 @entity1 .

Chronic Use of XXXX and Mortality in @entity1030 : A Meta-analysis.

@entity1 :: ('9606', 'Species') :: ['patients'] @entity2544 :: ('MESH:D013806', 'Chemical') :: ['theophylline', 'Theophylline'] @entity1354 :: ('8909', 'Gene') :: ['P=.11'] @entity1030 :: ('MESH:D029424', 'Disease') :: ['COPD', 'chronic obstruction pulmonary disease'] @entity204 :: ('MESH:D003643', 'Disease') :: ['death']
@entity2544 :: (MESH:D013806,Chemical) :: ['Theophylline']
