Thromb Haemost 2011; 106(03): 528-538
DOI: 10.1160/TH11-02-0061
New Technologies, Diagnostic Tools and Drugs
Schattauer GmbH

Validation of the CHADS2 clinical prediction rule to predict ischaemic stroke

A systematic review and meta-analysis
Claire Keogh
1   Royal College of Surgeons, Dublin, Ireland
,
Emma Wallace
1   Royal College of Surgeons, Dublin, Ireland
,
Ciara Dillon
1   Royal College of Surgeons, Dublin, Ireland
,
Borislav D. Dimitrov
1   Royal College of Surgeons, Dublin, Ireland
,
Tom Fahey
1   Royal College of Surgeons, Dublin, Ireland
› Author Affiliations
Financial support: This work was supported by the Health Research Board (HRB) of Ireland through the HRB Centre for Primary Care Research under Grant HRC/2007/1.
Further Information

Publication History

Received: 01 February 2011

Accepted after major revision: 03 June 2011

Publication Date:
24 November 2017 (online)

Summary

The CHADS2 predicts annual risk of ischaemic stroke in non-valvular atrial fibrillation. This systematic review and meta-analysis aims to determine the predictive value of CHADS2. The literature was systematically searched from 2001 to October 2010. Data was pooled and analysed using discrimination and calibration statistical measures, using a random effects model. Eight data sets (n=2815) were included. The diagnostic accuracy suggested a cut-point of ≥1 has higher sensitivity (92%) than specificity (12%) and a cut-point of ≥4 has higher specificity (96%) than sensitivity (33%). Lower summary estimates were observed for cut-points ≥2 (sensitivity 79%, specificity 42%) and ≥3 (specificity 77%, sensitivity 50%). There was insufficient data to analyse cut-points ≥5 or ≥6. Moderate pooled c statistic values were identified for the classic (0.63, 95% CI 0.52–0.75) and revised (0.60, 95% CI 0.43–0.72) view of stratification of the CHADS2 . Calibration analysis in-dicated no significant difference between the predicted and observed strokes across the three risk strata for the classic or revised view. All results were associated with high heterogeneity, and conclusions should be made cautiously. In conclusion, the pooled c statistic and calibration analysis suggests minimal clinical utility of both the classic and revised view of the CHADS2 in predicting ischaemic stroke across all risk strata. Due to high heterogeneity across studies and low event rates across all risk strata, the results should be interpreted cautiously. Further validation of CHADS2 should perhaps be undertaken, given the methodological differences between many of the available validation studies and the original CHADS2 derivation study.

 
  • References

  • 1 Heeringa J, van der Kuip DA, Hofman A. et al. Prevalence, incidence and lifetime risk of atrial fibrillation: the Rotterdam study. Eur Heart J 2006; 27: 949-953.
  • 2 Wolf PA, Abbott RD, Kannel WB. Atrial fibrillation as an independent risk factor for stroke: the Framingham Study. Stroke 1991; 22: 983-988.
  • 3 Hannon N, Sheehan O, Kelly L. et al. Stroke associated with atrial fibrillation--incidence and early outcomes in the north Dublin population stroke study. Cerebrovasc Dis 2010; 29: 43-49.
  • 4 Gage BF, Waterman AD, Shannon W. et al. Validation of clinical classification schemes for predicting stroke: results from the National Registry of Atrial Fibrillation. J Am Med Assoc 2001; 285: 2864-2870.
  • 5 Hart RG, Pearce LA. Current status of stroke risk stratification in patients with atrial fibrillation. Stroke 2009; 40: 2607-2610.
  • 6 Lip GY, Nieuwlaat R, Pisters R. et al. Refining clinical risk stratification for predicting stroke and thromboembolism in atrial fibrillation using a novel risk factor-based approach: the euro heart survey on atrial fibrillation. Chest 2010; 137: 263-272.
  • 7 McGinn TG, Guyatt GH, Wyer PC. et al. Users’ guides to the medical literature: XXII: how to use articles about clinical decision rules. Evidence-Based Medicine Working Group. J Am Med Assoc 2000; 284: 79-84.
  • 8 Reitsma JB, Glas AS, Rutjes AW. et al. Bivariate analysis of sensitivity and specificity produces informative summary measures in diagnostic reviews. J Clin Epidemiol 2005; 58: 982-990.
  • 9 Risk factors for stroke and efficacy of antithrombotic therapy in atrial fibrillation. Analysis of pooled data from five randomized controlled trials. Arch Intern Med 1994; 154: 1449-1457.
  • 10 van Walraven C, Hart RG, Singer DE. et al. Oral anticoagulants vs aspirin in non-valvular atrial fibrillation: an individual patient meta-analysis. J Am Med Assoc 2002; 288: 2441-2448.
  • 11 Masaki N, Suzuki M, Iwatsuka R. et al. Effectiveness of risk stratification according to CHADS2 score in Japanese patients with nonvalvular atrial fibrillation. Int Heart J 2009; 50: 323-329.
  • 12 Boccuzzi SJ, Martin J, Stephenson J. et al. Retrospective study of total healthcare costs associated with chronic nonvalvular atrial fibrillation and the occurrence of a first transient ischemic attack, stroke or major bleed. Curr Med Res Opin 2009; 25: 2853-2864.
  • 13 Jacobs LG, Billett HH, Freeman K. et al. Anticoagulation for stroke prevention in elderly patients with atrial fibrillation, including those with falls and/or early-stage dementia: a single-center, retrospective, observational study. Am J Geriatr Pharmacother 2009; 7: 159-166.
  • 14 Guo Y, Wu Q, Zhang L. et al. Antithrombotic therapy in very elderly patients with atrial fibrillation: is it enough to assess thromboembolic risk?. Clin Interv Aging 2010; 5: 157-162.
  • 15 Ruiz Ortiz M, Romo E, Mesa D. et al. Oral anticoagulation in nonvalvular atrial fibrillation in clinical practice: impact of CHADS(2) score on outcome. Cardiology 2010; 115: 200-204.
  • 16 Rossi A. Statistics of observational studies: basic concepts for medical writers. J Eur Med Writers Assoc 2009; 18: 165-168.
  • 17 Rietbrock S, Plumb JM, Gallagher AM. et al. How effective are dose-adjusted warfarin and aspirin for the prevention of stroke in patients with chronic atrial fibrillation? An analysis of the UK General Practice Research Database. Thromb Haemost 2009; 101: 527-534.
  • 18 Hylek EM, Rose AJ. Understanding low INR in clinical practice. Thromb Haemost 2009; 101: 417-418.
  • 19 Bont J, Hak E, Hoes AW. et al. Predicting death in elderly patients with community-acquired pneumonia: a prospective validation study reevaluating the CRB-65 severity assessment tool. Arch Intern Med 2008; 168: 1465-1468.
  • 20 National, Collaborating, Centre. et al. Atrial fibrillation: National clinical guideline for management in primary and secondary care.. London: Royal College of Physicians; 2006
  • 21 Singer DE, Albers GW, Dalen JE. et al. Antithrombotic therapy in atrial fibrillation: American College of Chest Physicians Evidence-Based Clinical Practice Guidelines (8th Edition). Chest 2008; 133: 546S-592S.
  • 22 Karthikeyan G, Eikelboom JW. The CHADS2 score for stroke risk stratification in atrial fibrillation--friend or foe?. Thromb Haemost 2010; 104: 45-48.
  • 23 Gorin L, Fauchier L, Nonin E. et al. Antithrombotic treatment and the risk of death and stroke in patients with atrial fibrillation and a CHADS2 score=1. Thromb Haemost 2010; 103: 833-840.
  • 24 Olesen JB, Lip GY, Hansen ML. et al. Validation of risk stratification schemes for predicting stroke and thromboembolism in patients with atrial fibrillation: nationwide cohort study. Br Med J 2011; 342: d124.
  • 25 Camm AJ, Kirchhof P, Lip GY. et al. Guidelines for the management of atrial fibrillation: the Task Force for the Management of Atrial Fibrillation of the European Society of Cardiology (ESC). Eur Heart J 2010; 31: 2369-2429.
  • 26 Eckman MH, Singer DE, Rosand J. et al. Moving the tipping point: the decision to anticoagulate patients with atrial fibrillation. Circ Cardiovasc Qual Outcomes 2011; 4: 14-21.