Background: CAP is associated with significant morbidity, annually accounting for billions of healthcare dollars. Proton-pump inhibitors (PPI) are a mainstay treatment for gastric acid suppression. Previous studies have suggested using PPIs may increase the risk of developing CAP.
Study design: Nested case control study.
Setting: Outpatient general practices, United Kingdom.
Synopsis: The association between PPI use and CAP was evaluated in a cohort of more than 7 million patients using the UK’s general-practice research database. Eligible participants were divided into two groups: case patients and control patients. Initial results indicated an increased risk of CAP with PPI use. After adjusting for confounding variables, the use of a PPI was strongly associated with CAP development when used within 30 days prior of the diagnosis, and most notably within 48 hours of diagnosis. It also was noted that the risk of developing CAP with longer-term PPI use was much lower. This inverse temporal relationship was noted in two previous studies. The limitations of this study were related to presumed adherence and compliance with PPI therapy. There also was no radiographic data to support the diagnosis of pneumonia in these cases, both of which could bias the results.
Bottom line: There appears to be an increased risk of CAP with PPI use. This risk is most notable within 48 hours. However, long-term, chronic PPI use was not associated with an increased risk of CAP.
Citation: Sarkar M, Hennessy S, Yang YX. Proton-pump inhibitor use and the risk for community-acquired pneumonia. Ann Intern Med. 2008;149:391-398.
Clopidogrel Prior to Percutaneous Intervention (PCI) Might Improve Outcomes in Patients with Acute ST-Elevation Myocardial Infarction (STEMI)
Clinical question: Does pretreatment with clopidogrel prior to PCI in acute STEMI improve outcomes?
Background: Extant guidelines for early utilization of clopidogrel in STEMI patients are based on results of studies of patients with non-ST-elevation acute coronary syndromes or treatment with thrombolytics.
Study design: Systematic review.
Setting: MEDLINE and Cochrane Controlled Trials Register of randomized controlled trials.
Synopsis: The authors selected 38 treatment groups, including 8,429 patients with STEMI who underwent primary PCI. They found a statistically significant difference in initial patency, and further found clopidogrel pretreatment was an independent predictor of early reperfusion and improved clinical outcome. This study suggests a benefit to pretreatment with clopidogrel but likely is not sufficient to establish such pretreatment as the standard of care. The limitations of this study were a retrospective review/meta-analysis, as the ability to limit the influence of confounding variables is reduced.
Bottom line: Pretreatment with clopidogrel in patients with acute STEMI undergoing primary PCI appears beneficial based on the results of this review of available evidence.
Citation: Vlaar PJ, Svilaas T, Damman K, et al. Impact of pretreatment with clopidogrel on initial patency and outcomes in patients treated with primary percutaneous coronary intervention for ST-segment elevation myocardial infarction: a systematic review. Circulation. 2008;118:1828-1836.
High-Dose Clopidogrel after PCI Is Beneficial
Clinical question: Does high-dose clopidogrel improve patient outcome following PCI?
Background: Studies have shown antiplatelet resistance after PCI is associated with an increased risk of cardiovascular events, including in-stent thrombosis and death. Other studies have shown the benefit of high-dose clopidogrel by the inhibition of platelet aggregation. Limited information is available regarding the applicability to patients after PCI.
Study design: Retrospective study of 2,954 consecutive patients divided into two groups, low-dose and high-dose clopidogrel use.
Setting: Single hospital in France.
Synopsis: The low-dose study group undergoing PCI was pretreated with 300 mg clopidogrel, followed by ASA 75 mg and clopidogrel 75 mg daily for two months. The second group undergoing PCI was pretreated with 600 mg clopidogrel followed by ASA 75 mg and clopidogrel 150 mg for 15 days, then maintained on ASA 75 mg and clopidogrel 75 mg. Patients received follow-up at two months and were evaluated for in-stent thrombosis, myocardial infarction (MI), death, and hemorrhagic complications. The two groups were matched one-to-one using propensity scoring and the nearest-pair-matching method blinded to patient outcome.