Age, Racial and Gender Knowledge Gaps about Hypertension,

Hypercholesterolemia and Coronary Artery Disease: Results from a

National Survey of Medical Decisions (DECISIONS)

JB Wong, MP Couper, CA Levin, J Van Hoewyk, BJ Zikmund-Fisher

Tufts Medical Center, University of Michigan, Foundation for Informed Medical Decision Making, VA Ann Arbor Healthcare System

5th International Shared Decision Making

Boston, MA USA

16 June 2009

Background

• Crossing the Quality Chasm: shared knowledge and the free flow of information

• Quality decision-making requires transfer of disease-specific knowledge

• Knowledge gaps– PCI: 75% prevent future MI & 71% prolong life

• No nationally representative sample has described knowledge in patients who made 1° or 2° heart disease treatment decisions

Holmbroe JGIM 2000; Inst of Medicine; Crossing the Quality Chasm 2001; Sepucha Health Aff 2004

Aim

• To assess knowledge in patients with hypertension, hypercholesterolemia or coronary heart disease

Methods

• DECISIONS survey – Nationally representative computer-assisted,

random digit dial telephone interview sample – 3010 English speaking US adults ≥40 years old

• Eligible if within past 2 years – Discussed or started cholesterol or high blood

pressure medications or– Had been told had coronary heart disease or had

heart attack, heart bypass, angioplasty or stent

Methods

• Knowledge questions – Normal levels (e.g., diastolic and systolic BP)– Treatment benefit and risk (e.g., MI with

cholesterol medication)– Treatment duration (e.g., recovery time PCI)

• Statistical analysis: Weighted regression• Estimates weighted for differential selection

probabilities and non-response

Results

• 1445 adults – mean age 61 – 10% <50, 20% 50-59, 27% 60-69, 43% 70+– 47% women– 4% Hispanic, 68% white, 19% black and 8% other

• 51% hypertension• 52% hypercholesterolemia• 29% coronary heart disease

Knowledge Results

18%

58% 52%30%

32%33%

52%

10% 15%

0%

20%

40%

60%

80%

100%

HBP #5 CHOL #4 CHD #5

<2 correct 2 correct >2 correct

Mean Correct by Decision

0%

20%

40%

60%

80%

100%

HBP CHOL CHD

HBP: Normal BP by Age

70% 69%

51%43%

59% 59%

43%34%

0%

20%

40%

60%

80%

100%

<50 50-59 60-69 >70

Co

rrec

t A

nsw

ers

Systolic Diastolic

P-value <0.0002

HBP: Normal BP by Race

40%

57%63%

56%63%

51%44%

21%

0%

20%

40%

60%

80%

100%

Hispanic White Black Other

Co

rrec

t A

nsw

ers

Systolic Diastolic

Diastolic P-value <0.01

CHOL: RR MI from Medication

15% 12%13% 12% 14%9% 11% 12%

21%16%

0%

20%

40%

60%

80%

100%

Race Age Sex

Co

rrec

t A

nsw

ers

CHOL: Adverse Effect by Race

10%21%

4%17%

0%

20%

40%

60%

80%

100%

Hispanic White Black Other

Co

rrec

t A

nsw

ers

P-value <0.01

CAD: PCI Recovery Time by Race

7%

32%

4%10%

0%

20%

40%

60%

80%

100%

Hispanic White Black Other

Co

rrec

t A

nsw

ers

P-value <0.002

CAD: Most Effective Angina Relief

0% 4%11% 6%

12%5% 8% 6%11% 14%

0%

20%

40%

60%

80%

100%

Race Age Sex

Co

rre

ct

An

sw

ers

Limitations

• Limited # of knowledge questions – Involve normal levels, survival, disease risk

or quality of life benefit, recovery time and adverse events

• Retrospective relying on recall– Restricted to procedures within 2 years to

minimize memory loss and maximize inclusion

• Patients may have gist but not knowledge

Conclusion

• Knowledge of patients with hypertension, hypercholesterolemia or coronary artery disease generally poor

• Results suggest that methods to inform patients could be improved

• Would increasing knowledge reduce care variation, enhance patient-MD engagement and improve the quality of their health care decision-making?