Linked Life Data

12034583

Source:http://linkedlifedata.com/resource/pubmed/id/12034583

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
11
pubmed:dateCreated
2002-5-29
pubmed:abstractText
The 1982-1988 aspirin component of the Physicians' Health Study, a randomized trial of aspirin and beta-carotene in primary prevention of cardiovascular disease and cancer among 22,071 US male physicians, was terminated early primarily because of a statistically extreme 44% reduction in first myocardial infarction, with inadequate precision and no apparent effect on the primary endpoint, cardiovascular death. Because of the demonstrated efficacy of aspirin in secondary prevention of cardiovascular death, nonfatal cardiovascular events may simultaneously be time-dependent confounders and intermediate variables. Aspirin use is strongly influenced by these as well as other diseases, side effects, and cardiovascular risk factors. The authors used a marginal structural model with time-dependent inverse probability weights to estimate the underlying causal effect of aspirin on cardiovascular mortality. Although intention-to-treat analyses found no effect (rate ratio = 1.00, 95% confidence interval (CI): 0.72, 1.38), the estimated causal rate ratio was altered to 0.75 but remained nonsignificant (95% CI: 0.48, 1.16). As-treated analyses suggested a more modest effect of aspirin use (rate ratio = 0.90, 95% CI: 0.65, 1.25). Although the numbers of cardiovascular deaths were insufficient to evaluate this endpoint definitively, use of such methods holds much potential for controlling time-varying confounders affected by previous exposure.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jun
pubmed:issn
0002-9262
pubmed:author
pubmed:issnType
Print
pubmed:day
1
pubmed:volume
155
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1045-53
pubmed:dateRevised
2007-11-15
pubmed:meshHeading
pubmed:year
2002
pubmed:articleTitle
Use of a marginal structural model to determine the effect of aspirin on cardiovascular mortality in the Physicians' Health Study.
pubmed:affiliation
Division of Preventive Medicine, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02215, USA. ncook@rics.bwh.harvard.edu
pubmed:publicationType
Journal Article, Clinical Trial, Research Support, U.S. Gov't, P.H.S., Randomized Controlled Trial