Is Better Patient Knowledge Associated with Different Treatment Preferences? A Survey of Patients with Stable Coronary Artery Disease

Figures & data

Table 1 Participant Characteristics

Characteristics	N=87
Age, SD	61.3 9.8
Female	34 (40.5%)
Race
Black	28 (32.3%)
White	49 (56.3%)
Neither Black or White	10 (11.5%)
Education level
8th grade or less	1 (1.1%)
Some high school	3(3.4%)
High school graduate or GED	23 (26.4%)
Some college or 2 year degree	27 (31.0%)
4-year college graduate	16 (18.4%)
Advanced degree	17 (19.5%)
Past MI	20 (33.0%)
Past PCI	31 (35.6%)
SAQ, SD	62.3 24.3
Preference for decision-making process
Doctor decides on his/her own	4 (4.6%)
Doctor listens to my opinion and then decides	13 (14.9%)
Doctor and I are equal partners in deciding	62 (71.3%)
I listen to doctor’s opinion and then I decide	8 (9.2%)
I decide on my own	0 (0%)
Insurance coverage
Medicaid	6 (6.9%)
Medicare	37 (42.5%)
Private Insurance	30 (34.5%)
Other Insurance or No Insurance	14 (16.1%)

Abbreviations: SD, standard deviation; GED, general education diploma; MI, myocardial infarction; PCI, percutaneous coronary intervention; SAQ, Seattle Angina Questionnaire.

Figure 1 Amount of provider-patient discussion of the benefits and risks of OMT and PCI as recalled by patients.

Figure 2 The association between amount of provider-patient benefit/risk discussion and a patient’s knowledge scores. Bolded predictors reached a p-value < 0.05.

Table 2 Predictors of Patient Preference for OMT Over PCI

	Age- and Sex-Adjusted Models		Multivariable-Adjusted Model^†
	OR (95% CI)	p-value	OR (95% CI)	p-value
Age	0.98 (0.93–1.04)	0.57	1.02 (0.95–1.10)	0.64
Female	0.54 (0.18–1.61)	0.27	0.78 (0.20–3.14)	0.72
Knowledge Score	0.82 (0.64–1.03)	0.09	0.85 (0.65–1.10)	0.21
Black	3.38 (1.09–11.03)	0.04	4.38 (1.09–19.82)	0.04
Education Level	1.09 (0.69–1.74)	0.71
History of PCI	0.23 (0.03–0.94)	0.07	0.22 (0.03–1.07)	0.09
History of MI	0.45 (0.07–1.90)	0.33
Decision Involvement^§	0.91 (0.40–2.17)	0.83
Seattle Angina Score	1.00 (0.98–1.03)	0.84
Importance of Cost*	2.29 (0.75–7.45)	0.15
Insurance (Ref: Private Insurance)**
Medicaid	0.98 (0.10–7.72)	0.99	0.33 (0.02–4.71)	0.43
Medicare	0.20 (0.04–0.86)	0.04	0.15 (0.02–0.94)	0.06
Other	0.12 (0.01–0.77)	0.06	0.04 (0.00–0.37)	0.01

Notes: Bolded predictors reached a p-value < 0.05 in the multivariable-adjusted model. ^†To avoid model overfitting, the multivariable-adjusted model was created by including only age, sex, knowledge score, and predictors with p-value < 0.10 in age- and sex-adjusted models. ^§Decision involvement refers to amount of a patient’s desired decision-making involvement (ordinal 5 point scale. 1 = patient did not want to be involved in decision-making, 5 = patient wanted to make decision completely on their own). *Importance of cost refers to patient-reported importance of out-of-pocket costs in making decision (0=no or minor effect, 1 = moderate or major effect). **Insurance odds ratios are in reference to patients with private insurance.

Abbreviations: OMT, optimal medical therapy; PCI, percutaneous coronary intervention; OR, odds ratios; CI, confidence interval; MI, myocardial infarction.

Figure 3 Preferences for stable CAD treatment by patient race.

Table 3 Predictors of Receiving PCI

	Age- and Sex-Adjusted Models		Multivariable-Adjusted Model^†
	OR (95% CI)	p-value	OR (95% CI)	p-value
Age	1.03 (0.99–1.09)	0.18	1.05 (0.98–1.13)	0.20
Female	1.46 (0.59–3.74)	0.42	1.65 (0.50–5.75)	0.42
Prefer OMT over PCI^‡	0.55 (0.16–1.71)	0.32	0.41 (0.09–1.70)	0.24
Black	0.93 (0.35–2.47)	0.88
Education Level	1.10 (0.75–1.60)	0.63
History of PCI	4.28 (1.58–12.28)	0.01	5.59 (1.76–20.23)	0.01
History of MI	1.82 (0.62–5.50)	0.27
Decision Involvement^§	2.38 (1.07–6.19)	0.05	2.48 (0.86–8.36)	0.11
Seattle Angina Score	1.01 (0.99–1.03)	0.27
Importance of Cost*	0.65 (0.25–1.64)	0.37
Insurance (Ref: Private Insurance)**
Medicaid/No Insurance	0.23 (0.01–2.14)	0.24	0.29 (0.01–2.92)	0.34
Medicare	0.40 (0.11–1.29)	0.13	0.32 (0.06–1.36)	0.14
Other	0.11 (0.01–0.51)	0.01	0.05 (0.00–0.34)	0.01

Notes: Bolded predictors reached a p-value < 0.05 in the multivariable-adjusted model. ^†To avoid model overfitting, the multivariable-adjusted model was created by including only age, sex, preference for OMT, and predictors with p-value < 0.10 in age- and sex-adjusted models. ^‡Prefer OMT over PCI refers to whether patient expressed an ultimate treatment preference for OMT instead of PCI. ^§Decision involvement refers to amount of a patient’s desired decision-making involvement (ordinal 5 point scale. 1 = patient did not want to be involved in decision-making, 5 = patient wanted to make decision completely on their own). *Importance of cost refers to patient-reported importance of out-of-pocket costs in making decision (0=no or minor effect, 1 = moderate or major effect). **Insurance odds ratios are in reference to patients with private insurance.

Abbreviations: OMT, optimal medical therapy; PCI, percutaneous coronary intervention; OR, odds ratios; CI, confidence interval; MI, myocardial infarction.