Of the 800 sampled for prostate surgery, three were found to be ineligible because they were deceased or lived in a nursing home. Of the 797 believed to be eligible, 685 returned a survey, a response rate of 86%.
Of the 800 stent patients sampled, 22 were ineligible because they had died, were in nursing homes, or because they reported they had not had a stent procedure near the date indicated in the claims. Of the 778 who were thought to be eligible, 593 returned a questionnaire, a response rate of 76%. Only 472 of those were included in this analysis for reasons outlined above.
We compared respondents and nonrespondents with respect to age, gender and race. There were no differences for either sample with respect to age. Male stent patients responded at a higher rate than females (p = 0.02); white prostate surgery patients responded at a higher rate than nonwhites (<0.001).
The average time between the procedure and receipt of a returned questionnaire was 14 months; that time did not differ by procedure.
Table 1 displays the basic demographic and clinical characteristics of the two samples. The prostate surgery patients were considerably younger than the stent patients, better educated, more likely to be married, and, of course, they were all male, whereas 38% of the stent patients were female. The self-rated health of the prostate surgery patients was better as well.
Fifty-four percent of the stent patients reported that they had had no arm or chest pain in the month preceding the sampled stent procedure; 28 percent had had a CABG in the past; 21 percent said they had had a heart attack at some time in the past, although not within a week of the stent procedure. Table 1 also presents the number of four co-morbid conditions (diabetes, heart failure, stroke history or COPD) reported by stent patients; these data were not collected for prostate cancer patients.
Table 2 presents data on how patients reported they interacted with physicians when making the decision to have the interventions. Prostate cancer surgery patients frequently (64%) reported that they were presented with at least one alternative to surgery (brachytherapy, external beam radiation or conservative management) to consider seriously; a third of them said that no immediate active treatment was presented as a serious option. Virtually all (95%) reported discussing the reasons for surgery “a lot” or “some”, while fewer (63%), but still a clear majority, reported “a lot” or “some” discussion of reasons they might not want surgery. Seventy-six percent said their physician asked them what they wanted to do. Prostate cancer surgery patients also were very likely (58%) to have gone on the Internet for information and to report talking with more than one doctor (67%) about the decision, although primary care physicians were seldom (1%) cited as having major input.
The dynamics of decision making reported by stent patients were quite different. Very few (10%) said they were presented with any alternative approach (CABG or conservative management) as a serious alternative to having a stent; only six percent were offered conservative management as a serious option. While most patients (77%) reported discussing the reasons for the intervention “a lot” or “some” with their physicians, only 19% said their physicians discussed the reasons they might not want the procedure “a lot” or “some”. Only 16% said that they were asked about their own treatment preference. The picture of a minimal decision making process was augmented by the facts that only 14% of stent patients reported going on the Internet for information and only 29% reported talking with more than one physician about the decision. Like prostate cancer surgery patients, stent patients seldom (3%) said a primary care doctor had major input about the decision.
Linear regression models were run to predict the Decision Process Scores for each procedure. The left-hand model in Table 3 for prostate cancer surgery patients shows that there is a significant tendency for patients with more education to report a more substantive decision making process for prostatectomy (p < 0.001); whites (p = 0.04) and those with partners (p = 0.02) also report a more extensive decision making process. However, patient age, self-reported health status, and evidence of cancer spread were unrelated to the Decision Process Score, as was time between surgery and completing the survey
For coronary artery disease, there may be a stronger case for inserting a stent, and hence perhaps less shared decision making, if the patient has severe angina or has had a previous MI or CABG. The stent model in Table 3 shows that patients who had a higher angina symptom score, reported a more (not less) extensive shared decision making process (p = 0.002). No patient demographic characteristics were significantly related to the decision-making process, nor were any of the other measures of their health status or histories, although those with a previous heart attack also tended to report more discussion (p = 0.07).