title: Statins and secondary prevention of venous thromboembolism: pooled analysis of published observational cohort studies.
abstract: OBJECTIVE
  There have been suggestions that statins may have a potential role in secondary prevention of venous thromboembolism (VTE) [which includes deep vein thrombosis (DVT) and pulmonary embolism (PE)], but the evidence is inconsistent. We aimed to evaluate the association between statin use and risk of recurrent VTE.
  
  
  RESULTS
  We conducted a systematic review and meta-analysis of observational cohort studies. All relevant studies which reported associations between statin use and recurrent VTE outcomes were identified from MEDLINE, EMBASE, Web of Science, and manual search of bibliographies from inception to January 2017. Study specific relative risks (RRs) with 95% confidence intervals were aggregated using random effects models. Eight eligible studies comprising of 103 576 participants and 13 168 recurrent VTE outcomes were included in the pooled analysis. In pooled analysis of 7 studies, the RR for recurrent VTE was 0.73 (0.68-0.79) when comparing statin use with no use. There was no evidence of heterogeneity between contributing studies (I2=0%, 0-71%; P = 0.93). The RRs for recurrent PE (three studies) and DVT (two studies) comparing statin use with no statin use were 0.75 (95% CI: 0.58-0.96) and 0.66 (95% CI: 0.60-0.71) respectively.
  
  
  CONCLUSIONS
  Available evidence from observational cohort studies suggests a beneficial effect of statin use on VTE recurrence. Well-designed intervention studies are needed to corroborate these findings.
authors.affiliation: Musculoskeletal Research Unit, School of Clinical Sciences, University of Bristol, Learning & Research Building (Level 1), Southmead Hospital, Southmead Road, Bristol BS10 5NB, UK.
authors.forename: Setor K
authors.initials: SK
authors.lastname: Kunutsor
authors.affiliation: Leicester Diabetes Centre, Leicester General Hospital, Gwendolen Road, Leicester LE5 4WP, UK.|Diabetes Research Centre, University of Leicester, Leicester General Hospital, Gwendolen Road, Leicester LE5 4WP, UK.
authors.forename: Samuel
authors.initials: S
authors.lastname: Seidu
authors.affiliation: Leicester Diabetes Centre, Leicester General Hospital, Gwendolen Road, Leicester LE5 4WP, UK.|Diabetes Research Centre, University of Leicester, Leicester General Hospital, Gwendolen Road, Leicester LE5 4WP, UK.
authors.forename: Kamlesh
authors.initials: K
authors.lastname: Khunti
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015331:Cohort Studies; D005260:Female; D006801:Humans; D019161:Hydroxymethylglutaryl-CoA Reductase Inhibitors / Q000627:therapeutic use*; D008297:Male; D008875:Middle Aged; D064887:Observational Studies as Topic; D012307:Risk Factors; D055502:Secondary Prevention; D054556:Venous Thromboembolism / Q000517:prevention & control*; D055815:Young Adult
chemical_list: D019161:Hydroxymethylglutaryl-CoA Reductase Inhibitors
keywords: Meta-analysis; Pulmonary embolism; Statin; Systematic review; Venous thromboembolism; Venous thrombosis; secondary prevention