Background

• Using the GWTG-Stroke database and the Centers for Medicare & Medicaid Service files, we analyzed Medicare patients

with acute ischemic stroke admitted to GWTG-Stroke hospitals between April 1, 2003 and December 12, 2008.

• We found concurrent controls at non-GWTG-Stroke hospitals using a matching process based upon average annual

ischemic stroke volume, calendar time, hospital teaching status, and hospital region.

• We defined 4 separate time periods of interest:

• PRE (18 mos-16 mos prior to joining GWTG-Stroke)

• RUN-UP (6 mos-1 day prior to GWTG-Stroke)

• EARLY (day 0-6 months after GWTG-Stroke)

• SUSTAINED (6 mos-18 mos after GWTG-Stroke).

• We further combined time periods:

• PRE+RUN-UP = BEFORE

• EARLY+SUSTAINED = AFTER.

• Using site-level Kaplan-Meier estimates and Kruskal-Wallis tests, we analyzed the GWTG-Stroke sites and the non-GWTG-

Stroke sites separately in each of the four time periods for the following clinical outcomes: length of stay, discharge home,

30 day mortality, 1 year mortality, 30 day all cause rehospitalization, 30 day stroke rehospitalization, 30 day cardiovascular

rehospitalization, 1 year all cause mortality, 1 year stroke mortality, and 1 year cardiovascular mortality .

• We also analyzed ischemic stroke patients enrolled during the PRE period in both GWTG-Stroke and non-GWTG-Stroke

hospitals utilizing a stratified/conditional Cox proportional hazard model with the pair number (1-366) as the stratum; we also

analyzed the data using the pre-period hospital level risk rate as an offset in each model.

• We performed risk adjusted mortality (30 day and 1 year) and discharge to home rates for what we determined to be the

most common baseline patient (female, 80 years, white, no medical history, and average-sized hospital).

*Outcome Sciences, Inc. is the data collection coordination center for the American Heart Association/American Stroke Association Get With The Guidelines® programs

Results Conclusions

Limitations

P<0.0001

• Stroke is a devastating disease, affecting more than 795,000 people in the U.S. each year.

• The Get With The Guidelines-Stroke (GWTG-Stroke) program was developed by the American Heart Association (AHA) as

a quality improvement program for hospitals to improve stroke care infrastructure utilizing a multidisciplinary team approach,

and offering data collection, decision support, and data feedback.

• Participation in the GWTG-Stroke program has also been associated with increased adherence to quality performance

measures and increased number of patients with stroke treated over time.

• Although   improvement of these quality of care measures, such as early antithrombotics and smoking cessation, have been

seen in patients at GWTG-Stroke hospitals, longer term clinical outcomes, such as mortality, discharge to home, or

rehospitalization has not been described.

Get With The Guidelines-Stroke Program Participation and Clinical Outcomes for Medicare Beneficiaries

Sarah Song MD, MPH1

, Gregg C. Fonarow MD2

, Wendy Pan PhD3

, DaiWai M Olson PhD, RN4

, Adrian F. Hernandez MD, MS5

, Eric D. Peterson MD, MPH5

,

Mathew J. Reeves PhD6

, Eric E. Smith MD, MPH7

, Lee H. Schwamm MD8

, Jeffrey L. Saver MD9

1Department of Neurology, Rush University Medical Center;

2Department of Cardiology, University of California-Los Angeles;

3Department of Biostatistics & Bioinformatics, Duke University;

4Department of Neurology, Duke University;

5Department of Cardiology, Duke University; 6Department of Epidemiology and Biostatistics, Michigan State University;

7Department of Clinical Neurosciences, Hotchkiss Brain Institute, University of Calgary;

8Department of Neurology, Massachusetts General Hospital;

9Department of

Neurology, University of California-Los Angeles

Author Disclosure Information:  S. Song: Research Grant; Modest; American Heart Association/Pharmaceutical Roundtable – Spina Outcomes Research Center.  G.C. Fonarow: None. W. Pan: None. D.M. Olson: None. A.F. Hernandez: None. E.D. Peterson: Research Grant; Modest; BMS/Sanofi, J&J, Lilly, PI of AHA Data Coordinating Center (for GWTG).  M.J. Reeves: None. E.E. Smith: None. L.H. Schwamm: Consultant/Advisory Board; Significant; Consultant Stroke Systems MA DPH. Other; Modest; Chair, AHA GWTG (unpaid).  J.L. Saver: None.

• In this study, we found that patients hospitalized with acute

ischemic stroke at GWTG-Stroke hospitals had greater

improvement of clinical outcomes over time, than similar non-

GWTG-Stroke hospitals.

• GWTG-Stroke hospitals exhibited reduced proportional 30 day

and 1 year mortality, and had more discharges home.

• Encouragingly, both linked and unlinked hospitals improved their

stroke outcome over time.

• The GWTG-Stroke program continues to show benefits of hospital

participation in clinical outcomes.

• Participation in GWTG-Stroke was voluntary and the control

hospitals while concurrent were not based on randomization.

• Despite our best efforts, matching GWTG-Stroke hospitals with

non-GWTG-Stroke hospitals was not perfect, and the matched

pairs had significant differences on most outcomes in the PRE

period

• Residual measured and unmeasured confounding may have

occurred

• There was a small amount of missing data which happened most

frequently in the SUSTAINED period, due to end of CMS data

reporting

Acknowledgements• NIH/NIA RCMAR/CHIME

• GWTG-Stroke is provided by the American Heart Association/American

Stroke Association and is currently supported, in part, by a charitable

contribution from Janssen Pharmaceutical Companies of Johnson &

Johnson. GWTG-Stroke has been funded in the past through support

from Boeringher-Ingelheim, Merck, Bristol-Myers Squib/Sanofi

Pharmceutical Partnership, and the AHA Pharmaceutical Roundtable.

A total of 173,985 patients, with 88,584 patients at 366 GWTG-Stroke sites, and 85,401 patients at

366 matched non-GWTG-Stroke sites included in the analysis.Patient characteristics were similar in

PRE and SUSTAINED periods.

In GWTG-Stroke hospitals between the PRE and the SUSTAINED periods, there was significantly

• Improved median 30-day mortality of 15.08% to 14.63%

• Improved median 1-year mortality of 28.25% to 27.59%

• Decreased median 30-day stroke rehospitalization of 4.36% to 4.05%

• Increased median 30-day cardiovascular disease rehospitalization of 3.03% to 3.08%

In non-GWTG-Stroke hospitals between the PRE and the SUSTAINED periods, there was significantly:

• Decreased median 30-day stroke rehospitalization of 4.55% to 4.27%

• Increased median 30-day cardiovascular rehospitalization of 2.65% to 2.94%

Univariate analysis of the SUSTAINED period found that clinical outcomes were similar, except that GWTG-Stroke hospitals had decreased stroke/TIA rehospitalizations at 1 year than

non-GWTG-Stroke hospitals: 15.2% compared to 16.4% (p<0.0002) 

GWTG-Stroke hospitals had statistically significantly improved outcomes than non-GWTG-Stroke hospitals during the PRE period for the following: discharge home, 30 and 1 year

mortality, 30 day cardiovascular rehospitalization, and 1 year stroke rehospitalization

Patient Characteristics Comparing Clinical Outcomes at GWTG-Stroke Hospitals to Non-GWTG-Stroke Hospitals

Hospital Characteristics

Overall PRE period (N = 58,830)

GWTG-Stroke hospital (N = 29,217)

Non-GWTG-Stroke hospital (N = 29,613)

P-value (Wilcoxon two-sample / Chi-square)

Patient age (mean) 79.43 years (SD 7.86)

79.60 years (SD 7.86)

79.27 years (SD 7.85)

P < 0.0001

Female % 59.98% 59.54 60.41% P < 0.030

White % 84.16% 85.45% 82.89% P < 0.0001

Comorbidities

Hypertension 77.90% 77.75% 78.06% P = 0.358

Acute myocardial infarction

10.44% 10.48% 10.39% P = 0.703

Stroke 8.83% 8.59% 9.06% P = 0.464

Coronary artery disease

33.90% 33.72% 34.08% P = 0.357

Diabetes 29.24% 28.31% 30.16% P < 0.0001

Pneumonia 8.55% 8.43% 8.67% P = 0.294

Renal disease 7.24% 7.06% 7.42% P = 0.094

COPD 19.17% 18.63% 19.70% P = 0.001

Dementia 4.58% 4.24% 4.92% P < 0.0001

Carotid stenosis 9.16% 9.38% 8.95% P = 0.069

Peripheral vascular disease

9.77% 9.73% 9.82% P = 0.705

Overall POST period (N = 57,056)

GWTG-Stroke hospital (N = 30,058)

Non-GWTG-Stroke hospital (N = 26,998)

P-value (Wilcoxon two-sample / Chi-square)

Patient age (mean) 79.65 (SD 7.99) 79.68 (7.97) 79.63 (SD 8.02) P<0.339

Female % 59.35% 58.82% 59.95% P<0.006

White % 84.38% 85.36% 83.29% P < 0.0001

Comorbidities

Hypertension 79.18% 79.04% 79.34% P = 0.374

Acute myocardial infarction

10.44% 10.89% 9.95% P=0.0002

Stroke 8.98% 9.82% 8.04% P<0.0001

Coronary artery disease

34.07% 34.59% 33.49% P=0.006

Diabetes 29.75% 29.39% 30.16% P=0.044

Pneumonia 8.96% 8.73% 9.21% P=0.046

Renal disease 13.34% 13.22% 13.49% P=0.347

COPD 19.95% 19.86% 20.05% P=0.567

Dementia 3.88% 3.85% 3.92% P=0.669

Carotid stenosis 11.29% 13.57% 8.76% P<0.0001

The majority of hospitals analyzed were from the South, followed by the Northeast; 2.73% of hospitals

were in rural areas. The overall mean number of beds per hospital was 278.5, and the mean number

of ischemic stroke discharges per hospital was 106.7.

Clinical Outcomes for GWTG-Stroke Hospitals vs. Non-GWTG-Stroke Hospitals during the PRE period

Unadjusted Analysis Adjusted Analysis

Hazard

RatioConfidence

IntervalProb

ChiSq

Hazard

RatioConfidence

IntervalProb

ChiSq

Discharge Home 1.018 1.002-1.035 0.0305 1.019 1.002-1.037 0.0291

Death in 30 day from admission 1.082 1.037-1.128 0.0003 1.097 1.050-1.146 <.0001

Death in 1 year from discharge 1.069 1.036-1.104 <.0001 1.083 1.047-1.120 <.0001

Any Rehospitalization in 30 days after Discharge 1.031 0.987-1.076 0.1686 1.028 0.982-1.075 0.2348

Stroke Rehospitalization in 30 days after Discharge 0.981 0.902-1.067 0.6543 0.968 0.887-1.058 0.4776

CVD Rehospitalization in 30 days after Discharge 1.168 1.039-1.312 0.0092 1.165 1.031-1.316 0.0146

Any Rehospitalization in 1 year after Discharge 0.991 0.967-1.016 0.4730 0.997 0.972-1.023 0.8207

Stroke Rehospitalization in 1 year after Discharge 0.940 0.894-0.989 0.0162 0.942 0.894-0.993 0.0267

CVD Rehospitalization in 1 year after Discharge 1.005 0.954-1.060 0.8376 1.013 0.959-1.070 0.6380

Ratio of Adjusted Hazard Ratios at GWTG-Stroke Hospitals vs. Changes at Non-GWTG-

Stroke Hospitals in RUN-UP, EARLY and SUSTAINED periods compared with PRE

period

RUN-UP vs. PRE EARLY vs. PRE SUSTAINED vs. PRE

Hazard

RatioConfidence

IntervalProb

ChiSq

Hazard

RatioConfidence

IntervalProb

ChiSq

Hazard

RatioConfidence

IntervalProb

ChiSq

Discharge Home1.086 1.059-1.114 <.0001 1.090 1.063-1.117 <.0001 1.097 1.078-1.117 <.0001

Death in 30 day from admission0.948 0.888-1.011 0.1053 0.894 0.839-0.953 0.0006 0.934 0.892-0.979 0.0040

Death in 1 year from discharge0.991 0.944-1.040 0.7119 0.889 0.848-0.933 <.0001 0.918 0.887-0.950 <.0001

Any Rehospitalization in 30 days after Discharge0.962 0.900-1.029 0.2568 1.006 0.943-1.073 0.8668 0.987 0.941-1.035 0.5841

Stroke Rehospitalization in 30 days after Discharge0.971 0.840-1.123 0.6937 0.900 0.781-1.037 0.1455 1.014 0.914-1.126 0.7872

CVD Rehospitalization in 30 days after Discharge0.950 0.856-1.049 0.5142 1.032 0.834-1.276 0.7745 0.923 0.788-1.081 0.3200

Any Rehospitalization in 1 year after Discharge0.990 0.953-1.027 0.5857 0.992 0.957-1.029 0.6789 0.987 0.962-1.014 0.3376

Stroke Rehospitalization in 1 year after Discharge0.954 0.880-1.033 0.2456 1.000 0.926-1.081 0.9921 1.002 0.948-1.060 0.9392

CVD Rehospitalization in 1 year after Discharge0.979 0.902-1.063 0.6186 1.081 1.000-1.167 0.0507 1.038 0.981-1.098 0.1966

By using the PRE period hospital level risk rate as an offset in each model, GWTG-Stroke hospitals had comparatively:

• Increased rates of discharge home in the earliest time comparison (PRE vs. RUN-UP)

• Decreased 30 day and 1 year mortality in both EARLY and SUSTAINED vs. PRE periods

Ratio of Adjusted HRs at GWTG-Stroke Hospitals vs. Changes at Non-GWTG-Stroke Hospitals: AFTER vs. BEFORE

Ratio of HRs

Confidence Interval

ProbChiSq

Discharge Home 1.075 1.060-1.091 <.0001Death in 30 day from admission 0.984 0.949-1.021 0.4002Death in 1 year from discharge 0.956 0.930-0.982 0.0013Any Rehospitalization in 30 days after Discharge 1.008 0.971-1.046 0.6940Stroke Rehospitalization in 30 days after Discharge 0.955 0.885-1.031 0.2355CVD Rehospitalization in 30 days after Discharge 1.050 0.949-1.161 0.3442Any Rehospitalization in 1 year after Discharge 0.981 0.960-1.002 0.0744Stroke Rehospitalization in 1 year after Discharge 0.955 0.914-0.998 0.0414CVD Rehospitalization in 1 year after Discharge 1.004 0.960-1.049 0.8599

When time periods were combined into BEFORE and AFTER periods, GWTG-Stroke hospitals had greater improvement over time in:

• Discharges to home

• Mortality at 1 year

The Most Common Baseline Stroke Patient GWTG-Stroke Non-GWTG-Stroke

Time Period Est. Rate Std. Err. Est. Rate Std. Err.

Risk adjusted 30-day MortalityPRE 16.77% 1.66% 17.76% 2.03%

RUN-UP 16.36% 2.40% 15.60% 2.27%

EARLY 14.42% 2.06% 16.16% 2.64%

SUSTAINED 14.71% 1.50% 15.39% 1.90%

BEFORE (PRE+RUN-UP) 16.64% 1.37% 16.25% 1.53%

AFTER (EARLY+SUSTAINED) 14.61% 1.21% 15.76% 1.55%

Risk adjusted 1-year MortalityPRE 27.83% 1.71% 28.02% 2.31%

RUN-UP 26.97% 2.58% 28.62% 3.27%

EARLY 24.69% 2.37% 24.49% 2.65%

SUSTAINED 23.36% 1.62% 26.92% 2.23%

BEFORE (PRE+RUN-UP) 27.27% 1.43% 28.14% 1.88%

AFTER (EARLY+SUSTAINED) 23.84% 1.34% 25.40% 1.72%

Risk adjusted discharge to home ratePRE 24.76% 1.35% 26.57% 1.50%

RUN-UP 25.51% 1.97% 26.01% 2.01%

EARLY 25.38% 1.78% 25.62% 2.01%

SUSTAINED 25.77% 1.31% 26.41% 1.52%

BEFORE (PRE+RUN-UP) 25.03% 1.11% 26.44% 1.20%

AFTER (EARLY+SUSTAINED) 25.68% 1.06% 26.18% 1.21%

• We analyzed risk adjusted mortality values and rates of discharge to home for what we deemed to be our most common baseline

patient

• We found that the risk adjusted 30 day mortality rate decreased for GWTG-Stroke patients from 16.77% in the PRE period to 14.71%

in the SUSTAINED period; comparatively, non-GWTG-Stroke patients had an improvement of mortality of 17.76% to 15.39% over the

same periods.

• There was a substantially greater degree of improvement in 30 day mortality when looking at BEFORE and AFTER rates, with GWTG-

Stroke hospitals offering an improvement of 16.64% to 14.61%, compared to 16.25% to 15.76%.

• For1 year mortality, BEFORE and AFTER rates revealed greater improvement in the GWTG-Stroke group, with BEFORE at 27.27%,

and AFTER at 23.84%; this was in comparison to non-GWTG-Stroke hospitals, who improved from 28.14% in the BEFORE period to

25.40% in the AFTER period.

Methods