Cardiac Rehabilitation The Evidence Base & Implications for Practice

Transcription

1 Cardiac Rehabilitation The Evidence Base & Implications for Practice Rod Taylor MSc, PhD Dept of Public Health & Epidemiology University of Birmingham Bisperbjerg Hospital, Copenhagen 11 th & 12 th December 2003

2 Presentation Update on the Cochrane systematic reviews of [exercise-based] CR? What are implications for current CR practice & future?

3 Acknowledgements Judy Jolliffee - St Loye s School of Health Studies, Exeter, UK Karen Rees - Department of Social Medicine, University of Bristol, UK Canadian Coordinating Centre for Health Technology Assessment (CCOHTA)

4 Exercise Based CR - Meta Analyses Oldridge 1988 O Connor 1989 Cochrane I 2000 Diagnosis MI MI CHD CHD Cochrane II 2003* RCTs (n) CCR/Ex only /14 30/19 Patients (n) 4,347 4,554 7,996 8,940 Outcomes Mortality Mortality Mortality Risk factors HRQL Mortality Risk factors HRQL Sub-group analysis *Taylor et al, Am J Med 2004 [in press]

5 Making policy decisions

6 Whose getting rehab? Exclusively MI Include CABG/PTCA Include Women Mean age Adequate concealment Outcome blinding %loss to follow up Percentage Trials before 1990 Trials since 1990

7 What s the overall impact of CR on events? Total mortality N=41 trials Cardiac Mortality N=31 trials Non fatal MI N=33 trials Need for CABG N=23 trials Need for PTCA N=12 trials Relative Risk FAVOURS REHABILITATION

8 Impact of CR Risk Factors Blood Pressure Systolic blood pressure (mmhg) [9 trials] Diastolic blood pressure (mmhg) [6 trials] Blood Lipids Total cholesterol (mmol/l) [19 trials] HDL cholesterol (mmol/l) [14 trials] LDL cholesterol (mmol/l) [14 trials] Triglycerides (mmol/l) [13 trials] Mean Reduction (95% CI) -0.5 (-6.5 to 5.5) -0.6 (4.5 to 2.8) (-0.56 to -0.11) 0.03 (-0.06 to 0.11) (-0.55 to -0.10) (-0.49 to -0.06) Relative Risk (95% CI) Smoking [13 trials] 0.77 (0.62 to 0.94)

9 Do we improve patient s quality of life? Nine trials (20%) assessed HRQoL using either validated measures or measures that covered 3 domains [physical, psychological and social well being] Range of both generic (SF-36, NHP, Karolinska, QWB, TTO) and disease specific HRQoL measures were used (QLMI). Although all RCTs studies improvement in HRQoL with CR, few studies reported improvements in excess of usual care

10 Other Cardiac Rx s how do we compare? ß-blockers Freemantle, 1999 ACE inhibitors NofE Gudelines, 2001 Statins La Rosa, 1999 Antiplatelets Antiplatelet trialists, 1994 Cardiac rehab Cochrane, trials [24,974] 22 trials [102,476] 3 trials [17,617] 11 trials [18,773] 44 trials [~9,000] Relative reduction in all cause mortality 23% (15% to 31%) Reduction in all cause mortality per 1000 per year 12 (6 to 17) 17% (2% to 11%) 4 (1 to 6) 23% (15% to 30%) 24% (16% to 32%) 4 (2 to 6) 7 (1 to 3) 16% (4% to 27%) 9 (15 to 116)

11 Comparative effects of cardiac treatments Trials demonstrate similar magnitude of total mortality benefit across drug, surgical and rehabilitative treatments for post MI patients Caveats in making such comparisons: I. Potential differences between trials other than therapies (1) Baseline risk (2) Inclusion of other Ix s [esp HF] (3) Inclusion of other Dx s (e.g. ß-blockers + ACE) II. Other outcomes side effects/hrqol

12 Are effects of CR additive? Rationale: Recent CR trials (1990 & beyond) patients will have had access to more active medical management (e.g. thrombolysis, statins, ACE) Expect: Effect size of CR trials before 1995 > Effect size of CR trials 1995 & after

13 Subgroups? Post MI only [23] All CHD diagnoses [9] EX CR [12] CCR [21] Dose 1,000 [5] Dose >1,000 [8] Follow up 24 months [17] Follow up >24 months [16] Publication up to 1995 [27] Publication after 1995 [6] Jadad score =<3 [28] Jadad score >3 [4] Odds Ratio

14 Are we effective in the long-term? Three CR RCTs assessed CR outcomes for 10-years Bethall et al (1999) 11 yr fu Hamalanien et al (1989 & 1995) 10 & 15 yr fu on Kallio trial Dorn et al (1999) 19 yr fu on NEDHP trial None report a significant reduction in mortality Implication Importance of maintenance of lifestyle changes

15 NEDHP survival curve

16 Heart Failure - Mortality

17 Heart Failure VO 2 max

18 The drug itself has no side effects - but the number of health economists needed to prove its value may cause dizziness and nausea 2

19 How much does CR cost? Gray et al (1997) Random selection of 16 UK CR centres Detailed collection of health service salary (1994) costs Centre cost per programme/year - 33K (95% CI: 28K to 38K) Patient cost per/year (95%CI: 262 to 332) Predictors of cost - No. of patients/centre, no. of patient hrs X - No. of assessments, equipment available, drop out rate & range of indications

20 Is CR Cost Effective? Author Setting Currency year Lowensteyn (2000) Cost Effectiveness Canada 1996 <$15,000 per LYG Ades (1997) US 1995 $4,950 per year of life Oldridge (1993) Canada 1991 $9,200 per QALY $21,800 per LYG

21 Comparative Cost Effectiveness Intervention Comparator Cost-effectiveness Ratio Smoking cessation program 97 No therapy US$220 per LYG* (1991) Education to promote cholesterol No intervention US$3,475 per LYG** (1999) reduction 118 Coronary artery angioplasty (one Medical care US$8,700 per QALY*** (1993) vessel, severe angina) 97 Lipid lowering (Simvastatin) for No therapy US$9,630 per LYG (1996) secondary prevention 97 Cardiac rehabilitation 98 (Included study - Oldridge et al. 1993) Usual care US$21,800 per LYG (1991) US$9,200 per QALY (1991) CABG 118 PTCA US$26,570 per LYG** (1999) Tissue plasminogen activator 118 Treatment with streptokinase US$35,257 per LYG** (1999) Thrombolytic reperfusion (t-pa, Streptokinase US$49,900 per LYG (1993) anterior MI, age 41-60) 97 Captopril (in 50 year old patients No captopril US$76,000 per QALY (1998) surviving MI) 117 Coronary artery angioplasty (one Medical care US$126,400 per QALY (1993) vessel, mild angina) 97

22 Can we (effectively) deliver in alternative settings? Bell (17) Miller (8,9,11) Sparks (29) Carlson (33)) Combined difference in exercise capacity METS

23 Conclusions Updated review of Cochrane systematic review of RCTs confirms medium term mortality and risk factor benefits of exercisebased CR Increasing evidence of these benefits not only in post MI patients but also other patient groups [revascularisation, angina and heart failure patients]

24 Conclusions cont Remains relatively little RCT evidence of CR in women and older individuals Positive impact of CR on quality of life remains unclear Limited evidence for the equivalence of home/community-based CR compared to traditional hospital-based programmes

25 Future Research Need good quality evidence for. Clinical & cost effectiveness of alternative models of CR/secondary prevention provision (e.g. primary care based nurse specialists) Impact of CR on patient HRQoL Effectiveness of strategies to enhance the uptake of CR in poorly represented population [women, older individuals, ethnic groups] Effectiveness of strategies to enhance the short-term & long-term compliance to CR/secondary prevention