L Laine

University of Southern California, Los Angeles, CA, United States

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Publications (117)1010.12 Total impact

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    ABSTRACT: Although gastroenterologists are asked to perform colonoscopy in patients with metastatic cancer of unknown primary (MCUP), studies evaluating this practice are lacking. To determine the yield and cost of colonoscopy in patients referred for colonoscopy with an indication of MCUP. We prospectively and retrospectively assessed colonoscopies performed from 2000 to 2011 at a county, a university, and a Veterans Administration medical centre to identify patients referred for colonoscopy for the indication of MCUP. Exclusion criteria included overt or occult bleeding, iron-deficiency anaemia, familial-colon-cancer syndrome, prior colon cancer, imaging suggesting colorectal lesion, and palpable rectal mass. Outcomes were the number of primary colon cancers and costs based on 2012 Medicare reimbursements. Two (1%) of the 160 patients meeting enrollment criteria had a primary colon cancer identified, and both died within 1 month after diagnosis without receiving therapy targeted at colon cancer. One patient without colon cancer had a perforation because of colonoscopy, which required surgery and colostomy. The cost of a strategy of routinely performing colonoscopy in patients referred with MCUP was $84 736 per colon primary identified. Primary colon cancer was rarely identified at colonoscopy in patients with MCUP and no standard indications for diagnostic colonoscopy. Furthermore, the cost to diagnose one additional colon primary was very high. Those with colon cancer had advanced disease and were unable to benefit from targeted therapy. Routine colonoscopy for MCUP cannot be recommended at present.
    Alimentary Pharmacology & Therapeutics 07/2013; · 4.55 Impact Factor
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    ABSTRACT: BACKGROUND: Scant information is available regarding patients with upper gastrointestinal bleeding (UGIB) from tumours. AIM: To determine the presentation, endoscopic findings, treatment and outcomes in patients with UGIB from malignant tumours and identify risk factors associated with rebleeding. METHODS: Consecutive patients who were hospitalised with haematemesis, melena or haematochezia and underwent upper endoscopy were identified retrospectively by reviewing an endoscopy database. Patients with UGIB due to biopsy-proven malignant tumours were studied. RESULTS: Tumours were the source of bleeding in 106 (5%) of 2,166 patients with UGIB. Tumours were oesophageal in 17 (16%), gastric in 77 (73%) and duodenal in 12 (11%). At presentation, 84 (79%) did not have known cancer previously, and 79 (75%) had metastatic disease. Seventy-seven (73%) received transfusions at index hospitalisation. At endoscopy, 32 (30%) had active bleeding (31 oozing, 1 spurting). Among actively bleeding patients, haemostasis was achieved in 12 (86%) of 14 receiving endoscopic therapy and all 18 not receiving endoscopic treatment. Hospitalisation for rebleeding occurred in 50 (49%) of 103 at a median of 30 days (3-885). On multivariate analysis, age ≤60 years (OR = 2.49, 95% CI 1.06-5.81) and haemodynamic instability (OR = 2.42, 95% CI 1.08-5.46) were associated with rebleeding. CONCLUSIONS: Patients presenting with tumour-associated UGIB have substantial blood loss, with three-quarters requiring transfusion at presentation. Initial haemostasis occurs in almost all patients, with or without endoscopic therapy, but rebleeding requiring repeat hospitalisation occurs in approximately half the patients and is more common in patients who are ≤60 years of age and have haemodynamic instability at presentation.
    Alimentary Pharmacology & Therapeutics 05/2013; · 4.55 Impact Factor
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    ABSTRACT: PURPOSE: Low-dose aspirin (ASA) increases the risk of upper gastrointestinal (GI) complications. Proton pump inhibitors (PPIs) reduce these upper GI side effects, yet patient compliance to PPIs is low. We determined the cost-effectiveness of gastroprotective strategies in low-dose ASA users considering ASA and PPI compliance. METHODS: Using a Markov model we compared four strategies: no medication, ASA monotherapy, ASA+PPI co-therapy and a fixed combination of ASA and PPI for primary and secondary prevention of ACS. The risk of acute coronary syndrome (ACS), upper GI bleeding and dyspepsia was modeled as a function of compliance and the relative risk of developing these events while using medication. Costs, quality adjusted life years and number of ACS events were evaluated, applying a variable risk of upper GI bleeding. Probabilistic sensitivity analyses were performed. RESULTS: For our base case patients using ASA for primary prevention of ACS no medication was superior to ASA monotherapy. PPI co-therapy was cost-effective (incremental cost-effectiveness ratio [ICER] 10,314) compared to no medication. In secondary prevention, PPI co-therapy was cost-effective (ICER 563) while the fixed combination yielded an ICER < 20,000 only in a population with elevated risk for upper GI bleeding or moderate PPI compliance. PPI co-therapy had the highest probability to be cost-effective in all scenarios. PPI use lowered the overall number of ACS. CONCLUSIONS: Considering compliance, PPI co-therapy is likely to be cost-effective in patients taking low dose ASA for primary and secondary prevention of ACS, given low PPI prices. In secondary prevention, a fixed combination seems cost-effective in patients with elevated risk for upper GI bleeding or in those with moderate PPI compliance. Both strategies reduced the number of ACS compared to ASA monotherapy.
    Cardiovascular Drugs and Therapy 02/2013; · 2.67 Impact Factor
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    ABSTRACT: BACKGROUND: The vascular and gastrointestinal effects of non-steroidal anti-inflammatory drugs (NSAIDs), including selective COX-2 inhibitors (coxibs) and traditional non-steroidal anti-inflammatory drugs (tNSAIDs), are not well characterised, particularly in patients at increased risk of vascular disease. We aimed to provide such information through meta-analyses of randomised trials. METHODS: We undertook meta-analyses of 280 trials of NSAIDs versus placebo (124,513 participants, 68,342 person-years) and 474 trials of one NSAID versus another NSAID (229,296 participants, 165,456 person-years). The main outcomes were major vascular events (non-fatal myocardial infarction, non-fatal stroke, or vascular death); major coronary events (non-fatal myocardial infarction or coronary death); stroke; mortality; heart failure; and upper gastrointestinal complications (perforation, obstruction, or bleed). FINDINGS: Major vascular events were increased by about a third by a coxib (rate ratio [RR] 1.37, 95% CI 1.14-1.66; p=0.0009) or diclofenac (1.41, 1.12-1.78; p=0.0036), chiefly due to an increase in major coronary events (coxibs 1.76, 1.31-2.37; p=0.0001; diclofenac 1.70, 1.19-2.41; p=0.0032). Ibuprofen also significantly increased major coronary events (2.22, 1.10-4.48; p=0.0253), but not major vascular events (1.44, 0.89-2.33). Compared with placebo, of 1000 patients allocated to a coxib or diclofenac for a year, three more had major vascular events, one of which was fatal. Naproxen did not significantly increase major vascular events (0.93, 0.69-1.27). Vascular death was increased significantly by coxibs (1.58, 99% CI 1.00-2.49; p=0.0103) and diclofenac (1.65, 0.95-2.85, p=0.0187), non-significantly by ibuprofen (1.90, 0.56-6.41; p=0.17), but not by naproxen (1.08, 0.48-2.47, p=0.80). The proportional effects on major vascular events were independent of baseline characteristics, including vascular risk. Heart failure risk was roughly doubled by all NSAIDs. All NSAID regimens increased upper gastrointestinal complications (coxibs 1.81, 1.17-2.81, p=0.0070; diclofenac 1.89, 1.16-3.09, p=0.0106; ibuprofen 3.97, 2.22-7.10, p<0.0001; and naproxen 4.22, 2.71-6.56, p<0.0001). INTERPRETATION: The vascular risks of high-dose diclofenac, and possibly ibuprofen, are comparable to coxibs, whereas high-dose naproxen is associated with less vascular risk than other NSAIDs. Although NSAIDs increase vascular and gastrointestinal risks, the size of these risks can be predicted, which could help guide clinical decision making. FUNDING: UK Medical Research Council and British Heart Foundation.
    Lancet. 01/2013; 382(9894):769-79.
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    ABSTRACT: Factors other than acid may play a role in gastro-oesophageal reflux disease (GERD) and its complications. To assessed the role of bile acids in the pathogenesis of GERD, Barrett's oesophagus and Barrett's-related neoplasia. We conducted a systematic review of computerised bibliographic databases for original articles involving humans or human oesophageal tissue or cells that assessed exposure to or manipulation of bile acids. Outcomes assessed included GERD symptoms; gross oesophageal injury; Barrett's oesophagus and related neoplasia; and intermediate markers of inflammation, proliferation or neoplasia. Eighty-three original articles were included. In in vivo studies, bile acids concentrations were higher in the oesophageal aspirates of patients with GERD than controls, and bile acids infusions triggered GERD symptoms, especially in high concentrations or in combination with acid. In ex vivo/in vitro studies, bile acids stimulated squamous oesophageal cells and Barrett's epithelial cells to produce inflammatory mediators (e.g., IL-8 and COX-2) and caused oxidative stress, DNA damage and apoptosis. They also induced squamous cells to change their gene expression pattern to resemble intestinal-type cells and caused Barrett's cells to increase expression of intestinal-type genes. In aggregate, these studies suggest that bile acids may contribute to the pathogenesis of symptoms, oesophagitis and Barrett's metaplasia with related carcinogenesis in patients with GERD. However, all study results are not uniform and substantial differences in study parameters may explain at least some of this variation.
    Alimentary Pharmacology & Therapeutics 07/2011; 34(2):146-65. · 4.55 Impact Factor
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    ABSTRACT: Current PPIs may not achieve desired outcomes in some GERD patients due to limited duration of acid inhibition. To evaluate a novel rabeprazole extended release (ER), which provides longer duration of drug exposure and acid suppression, in healing and symptomatic resolution of moderate-severe erosive oesophagitis. Patients with LA grade C or D oesophagitis were randomised to rabeprazole-ER 50 mg or esomeprazole 40 mg once daily in two identical 8-week double-blind trials (N = 2130). Two primary endpoints were tested sequentially: (1) healing by 8 weeks [hypothesis: rabeprazole-ER non-inferior to esomeprazole (non-inferiority margin = 8%)], (2) healing by 4 weeks [hypothesis: rabeprazole-ER superior to esomeprazole (P < 0.05)]. The secondary endpoint was sustained heartburn resolution at 4 weeks. Rabeprazole-ER was non-inferior to esomeprazole in week-8 healing (80.0% vs. 75.0%; 77.5% vs. 78.4%). Week-4 healing (54.8% vs. 50.3%; 50.9% vs. 50.7%) and sustained heartburn resolution (48.3% vs. 48.2%; 53.2% vs. 52.5%) were not significantly different. Post hoc combined results for grade D revealed rabeprazole-ER vs. esomeprazole differences in week-8 healing = 10.4% (95% CI: -1.4%, 22.2%) and week-4 healing = 12.0% (P = 0.048). Rabeprazole-ER is as effective as esomeprazole in healing moderate-severe oesophagitis and achieves similar rates of heartburn resolution. Subgroup analysis suggests the possibility of benefit in severe oesophagitis, but this requires further evaluation (ClinicalTrials.gov: NCT00658528 and NCT00658775).
    Alimentary Pharmacology & Therapeutics 01/2011; 33(2):203-12. · 4.55 Impact Factor
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    ABSTRACT: Nonsteroidal anti-inflammatory drugs (NSAID)-related GI effects vary based on patient characteristics. To assess risk factors for NSAID-associated upper GI clinical events and dyspepsia. Patients ≥50 years with osteoarthritis or rheumatoid arthritis were randomized to etoricoxib or diclofenac in a prespecified intent-to-treat analysis of three double-blind randomized trials. Potential risk factors for upper GI clinical events (bleeding, perforation, obstruction, or ulcer), complicated events (perforation, obstruction, bleeding) and discontinuations due to dyspepsia were assessed with Cox proportional hazard models. Significant predictors of clinical events and complicated events included age ≥65 years [hazards ratios (HRs) = 2.25 (1.84-2.76), 4.09 (2.82-5.92)], prior event [HRs = 2.57 (1.94-3.39), 3.23 (2.09-5.00)], low-dose aspirin [HRs = 2.34 (1.87-2.92), 3.41 (2.33-5.00)] and corticosteroid [HRs = 1.85 (1.41-2.43), 2.09 (1.29-3.38)]. Predictors of discontinuation due to dyspepsia included prior dyspepsia [HR = 1.78 (1.44-2.00)], prior event [HR = 1.78 (1.40-2.27)] and age ≥65 years [HR = 1.35 (1.16-1.57)]. Assessment for age ≥65 years, prior upper GI clinical events and low-dose aspirin use are key in identifying patients who should either avoid NSAIDs or employ management strategies to reduce NSAID-associated upper GI events. Prior dyspepsia or upper GI clinical events and age ≥65 years also predict an increased risk of developing dyspepsia severe enough to necessitate discontinuation of NSAIDs.
    Alimentary Pharmacology & Therapeutics 11/2010; 32(10):1240-8. · 4.55 Impact Factor
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    ABSTRACT: Protective co-therapy is recommended in NSAID users with GI risk factors, but adherence is poor. To assess the proportion of NSAID users receiving co-therapy and strategies to improve adherence. Arthritis patients > or =50 years of age received etoricoxib or diclofenac in a double-blind randomized trial. Reminders that high-risk patients (age > or = 65; previous ulcer/haemorrhage; corticosteroid, anticoagulant, aspirin use) should receive co-therapy were given at study initiation. Free PPI was provided. An intervention midway through the study included a written reminder and required written response regarding co-therapy. 16,244/23,504 (69%) patients had GI risk factors. Pre-intervention, co-therapy was most common with previous ulcer/haemorrhage [706/1107 (64%)] and 3-4 risk factors [331/519 (64%)]. In the 10,026 patients enrolled pre-intervention and remaining in the study > or =6 months after, co-therapy in high-risk patients increased from 2958/6843 (43%) to 4177/6843 (61%) (difference = 18%; 95% CI 16%,19%). The increase was greater outside the US (22%; 19%,24%) than in the US (15%; 13%,17%). Less than 50% of NSAID users with GI risk factors are given protective co-therapy--even if prescribers are given reminders and cost is not an issue. Direct communication requiring written response significantly increased adherence to guidelines, but achieving higher levels of adherence will require additional strategies.
    Alimentary Pharmacology & Therapeutics 07/2009; 30(7):767-74. · 4.55 Impact Factor
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    ABSTRACT: Although 'best practice' guidelines for dyspepsia management have been disseminated, it remains unclear whether providers adhere to these guidelines. To compare adherence to 'best practice' guidelines among dyspepsia experts, community gastroenterologists and primary-care providers (PCPs). We administered a vignette survey to elicit knowledge and beliefs about dyspepsia including a set of 16 best practices, to three groups: (i) dyspepsia experts; (ii) community gastroenterologists and (iii) PCPs. The expert, community gastroenterologist and PCP groups endorsed 75%, 73% and 57% of best practices respectively. Gastroenterologists were more likely to adhere with guidelines than PCPs (P < 0.0001). PCPs were more likely to define dyspepsia incorrectly, overuse radiographic testing, delay endoscopy, treat empirically for Helciobacter pylori without confirmatory testing and avoid first-line proton pump inhibitors (PPIs). PCPs had more concerns about adverse events with PPIs [e.g. osteoporosis (P = 0.04), community-acquired pneumonia (P = 0.01)] and higher level of concern predicted lower guideline adherence (P = 0.04). Gastroenterologists are more likely than PCPs to comply with best practices in dyspepsia, although compliance remains incomplete in both groups. PCPs harbour more concerns regarding long-term PPI use and these concerns may affect therapeutic decision making. This suggests that best practices have not been uniformly adopted and persistent guideline-practice disconnects should be addressed.
    Alimentary Pharmacology & Therapeutics 04/2009; 29(8):871-81. · 4.55 Impact Factor
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    ABSTRACT: When faced with the same facts, physicians often make different decisions. Aim To perform a survey to measure the process of care and variations in decision-making in nonvariceal upper gastrointestinal tract haemorrhage (NVUGIH) and compare results between experts and non-experts. We administered a vignette survey to elicit knowledge and beliefs about NVUGIH, including 13 'best practice' guidelines. We compared guideline compliance between experts and non-experts. One hundred and eighty-eight gastroenterologists responded (46%). Experts endorsed more 'best practices' than non-experts (93% vs. 85%; P = 0.002). Non-experts were more likely to endorse incorrectly bolus dosing vs. continuous infusion of intravenous proton pump inhibitors (PPIs; 92% vs. 64%; P = 0.005) and to select standard-channel vs. large-channel endoscopes in high-risk bleeding (100% vs. 85%; P = 0.04). There were wide variations within groups regarding the timing of nasogastric lavage, use of promotility agents, use of hemoclips and appropriateness of snaring clots overlying ulcers. Experts are more likely to comply with NVUGIH guidelines. Non-experts diverge from experts in the dosing of PPIs and choice of endoscope in high-risk bleeding. Moreover, there are wide variations in key practices even within groups. This suggests that best practices have been generally well disseminated, but that persistent disconnects exist that should be further investigated.
    Alimentary Pharmacology & Therapeutics 09/2008; 28(10):1199-208. · 4.55 Impact Factor
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    Nature Clinical Practice Gastroenterology &#38 Hepatology 04/2008; 5(3):120-1. · 5.33 Impact Factor
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    Nature Clinical Practice Gastroenterology &#38 Hepatology 03/2008; 5(2):60-1. · 5.33 Impact Factor
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    Nature Clinical Practice Gastroenterology &#38 Hepatology 02/2008; 5(1):2-3. · 5.33 Impact Factor
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    L. Laine
    Alimentary Pharmacology & Therapeutics (Suppl) 02/2007; 25(3):346-347.
  • K.R. McQuaid, L. Laine
    American Journal of Ophthalmology 01/2007; 143(1):194. · 4.02 Impact Factor
  • Revue du Rhumatisme 11/2006; 73(10):1061-1061.
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    L Laine
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    ABSTRACT: This review examines ulcers and gastrointestinal bleeding with low-dose aspirin, focusing on randomized placebo-controlled trials. The single endoscopic trial assessing ulcers showed no significant difference in 12-week ulcer incidence: 6% of 381 given placebo vs. 7% of 387 given 81 mg enteric-coated aspirin. The relative risk of major gastrointestinal bleeding with low-dose aspirin in a meta-analysis of placebo-controlled trials of vascular protection was 2.07 (95% CI: 1.61-2.66). The absolute rate increase with aspirin above placebo was 0.12% per year (95% CI: 0.07-0.19%) with a number-needed-to-harm of 833 patients (95% CI: 526-1429). A meta-analysis of aspirin 50-1500 mg daily reported an odds ratio for any gastrointestinal bleeding of 1.68 (95% CI: 1.51-1.88) with an number-needed-to-harm at 1 year of 247. The relative risk of hospitalization for upper gastrointestinal bleeding with low-dose aspirin in a large Danish cohort study was 2.6 (95% CI: 2.2-2.9) with an absolute annual incidence of 0.6%. Factors that may increase the risk of gastrointestinal bleeding include prior history of ulcers or gastrointestinal bleeding, corticosteroid use, anticoagulant therapy and addition of a non-aspirin non-steroidal anti-inflammatory drug. When determining whether low-dose aspirin is appropriate for an individual patient, the cardiovascular benefit must be weighed against the potential for clinical events such as gastrointestinal bleeding.
    Alimentary Pharmacology & Therapeutics 10/2006; 24(6):897-908. · 5.48 Impact Factor
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    ABSTRACT: Lower gastrointestinal effects of non-steroidal anti-inflammatory drugs (NSAIDs) are much more poorly characterized than upper gastrointestinal effects. To determine if NSAIDs increase lower gastrointestinal adverse effects and if the risk with non-selective NSAIDs is greater than with cyclooxygenase-2-selective inhibitors (coxibs). Computerized databases were searched to identify studies of NSAID use reporting on lower gastrointestinal integrity (e.g. permeability), visualization (e.g. erosions, ulcers) and clinical events. Designs in 47 studies were randomized (18), case-control (14), cohort (eight) and before-after (seven). Non-selective-NSAIDs had significantly more adverse effects vs. no NSAIDs in 20 of 22 lower gastrointestinal integrity studies, five of seven visualization studies, seven of 11 bleeding studies (OR: 1.9-18.4 in case-control studies), two of two perforation studies (OR: 2.5-8.1) and five of seven diverticular disease studies (OR: 1.5-11.2). Coxibs had significantly less effect vs. non-selective-NSAIDs in three of four integrity studies, one endoscopic study (RR mucosal breaks: 0.3), and two randomized studies (RR lower gastrointestinal clinical events: 0.5; haematochezia: 0.4). An increase in lower gastrointestinal injury and clinical events with non-selective-NSAIDs appears relatively consistent across the heterogeneous collection of trials. Coxibs are associated with lower rates of lower gastrointestinal injury than non-selective-NSAIDs. More high-quality trials are warranted to more precisely estimate the effects of non-selective-NSAIDs and coxibs on the lower gastrointestinal tract.
    Alimentary Pharmacology & Therapeutics 10/2006; 24(5):751-67. · 5.48 Impact Factor
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    ABSTRACT: Treatment with a continuous i.v. proton pump inhibitor is presumed to promote clot formation and stability by sustaining intragastric pH > or = 6. We postulated that very frequent oral dosing of proton pump inhibitors should simulate i.v. infusion and achieve similar pH control. Twenty healthy volunteers were stratified by Helicobacter pylori status (10 positive; 10 negative) and had determination of CYP2C19 status. After an overnight fast, an intragastric pH probe was placed. Subjects received 120 mg of lansoprazole at 8 am and 30 mg every 3 h until 8 pm. Intragastric pH was measured over 24 h, and lansoprazole plasma concentrations were determined at five time points. Intragastric pH was > or = 6 for 41% (95% CI: 30-53%) of the 15-h period from 8 am-11 pm and 46% (95% CI: 35-56%) of the 24-h period (8-8 am). The mean proportion of patients with pH > or = 6 was not significantly different in H. pylori-positive vs. negative patients. Only 25% of subjects sustained pH > or = 6 for at least 60% of the 15-h period, and 35% had a sustained pH > or = 6 for at least 60% of the 24-h period. A dose of 120 mg of oral lansoprazole followed by standard 30 mg doses of lansoprazole every 3 h did not reliably sustain pH at the desired level of 6.
    Alimentary Pharmacology & Therapeutics 07/2006; 23(11):1607-13. · 5.48 Impact Factor
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    J H Rubenstein, L Laine
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    ABSTRACT: Non-steroidal anti-inflammatory drugs have been implicated in reports of liver injury. However, the precise risk of non-steroidal anti-inflammatory drugs for this rare complication is unknown. To review systematically the published literature of population-based epidemiological studies reporting the incidence or comparative risk of non-steroidal anti-inflammatory drugs for liver injury resulting in clinically significant events, defined as hospitalization or death. Duplicate extraction of the methodological quality, design, source, population, years studied, particular non-steroidal anti-inflammatory drugs studied, definitions, patient counts and follow-up, and the adjustment for confounders. Seven articles met inclusion criteria. The comparative risk of liver injury resulting in hospitalization for current non-steroidal anti-inflammatory drug users compared with past non-steroidal anti-inflammatory drug users ranged from 1.2 to 1.7, but none was statistically significant. The incidence of liver injury resulting in hospitalization ranged from 3.1 to 23.4/100,000 patient-years of current use of non-steroidal anti-inflammatory drugs, with an excess risk compared with past non-steroidal anti-inflammatory drugs users of 4.8-8.6/100,000 patient-years of exposure. There were zero deaths from liver injury associated with non-steroidal anti-inflammatory drugs use in over 396,392 patient-years of cumulative exposure. These findings allow for the possibility of a small increase in the risk of clinically relevant hepatotoxicity with non-steroidal anti-inflammatory drugs use, but do not document that such a risk occurs.
    Alimentary Pharmacology & Therapeutics 09/2004; 20(4):373-80. · 5.48 Impact Factor

Publication Stats

6k Citations
1,010.12 Total Impact Points


  • 1988–2013
    • University of Southern California
      • • Division of Gastrointestinal and Liver Diseases
      • • Keck School of Medicine
      • • Department of Medicine
      Los Angeles, CA, United States
  • 2008
    • University of Zurich
      • Klinik für Gastroenterologie und Hepatologie
      Zürich, ZH, Switzerland
  • 1992–2007
    • Keck School of Medicine USC
      Los Angeles, California, United States
    • McMaster University
      • Department of Clinical Epidemiology and Biostatistics
      Hamilton, Ontario, Canada
  • 2004
    • Cerner Corporation
      Kansas City, Missouri, United States
  • 1999–2004
    • University of Michigan
      • Division of Gastroenterology
      Ann Arbor, MI, United States
    • Uniformed Services University of the Health Sciences
      Maryland, United States
    • St. Elizabeth's Medical Center
      Boston, Massachusetts, United States
    • Concordia University–Ann Arbor
      Ann Arbor, Michigan, United States
  • 1991–2002
    • University of California, Los Angeles
      • Department of Medicine
      Los Angeles, California, United States
  • 1995
    • Baylor College of Medicine
      Houston, Texas, United States
  • 1994
    • Minneapolis Veterans Affairs Hospital
      Minneapolis, Minnesota, United States