We identified a total of 33,675 patients for the prospective cohort and 32,810 patients for the retrospective cohort (). Compared with the retrospective cohort, individuals in the prospective cohort were younger, were less likely to be male, and had less comorbidity. In both cohorts, colorectal cancer was the most common cancer, and prostate cancer was the least common. The median number of days between diagnosis and death was 539 days for the prospective cohort and 1,053 days for the retrospective cohort. Within the prospective cohort, individuals with a higher predicted probability of death were older, were more likely to be male, were more likely to have lung cancer, and were more likely to have later stage disease than individuals with a lower probability of death. The median number of days from diagnosis to death decreased from 539 days for the full cohort to 73 days for the subgroup, with a predicted probability of death of greater than 80%.
Baseline Characteristics of Patients From the Combined Pennsylvania and New Jersey Cancer Registries
Among patients from PA, almost all patients saw a primary care physician, whereas only 46% to 62% were seen by a medical oncologist (). In the prospective cohort, the proportion of patients seen by a surgeon declined as the probability of death increased, whereas the proportion of patieints who were seeing an oncologist increased. The characteristics of the oncologists were similar in both cohorts. Among patients who had at least one hospitalization, approximately 40% of both cohorts received care at an NCI-designated cancer facility (69 of 207 hospitals), and approximately 20% were hospitalized at a teaching hospital. Greater than 98% of all hospitalizations occurred at a nonprofit facility. Hospital characteristics did not vary between the cohorts.
Characteristics of Physicians and Medical Oncologists From Pennsylvania
lists the proportion of patients who received the end-of-life benchmarks in the prospective and retrospective cohorts. In both cohorts, use of long-acting opiates alone or in combination was low (< 20%). In the prospective cohort, use of long-acting opiates and hospice was greater among those with a higher probability of death. The majority of patients in both cohorts were never admitted to hospice. In the prospective cohort, approximately one quarter of these patients received chemotherapy or had greater than one ED visit, and one third had greater than one hospitalization. These rates were lower in the retrospective cohort. In the prospective cohort, the probability of chemotherapy toxicity was higher among those with a higher probability of death. There were temporal increases in the use of chemotherapy, ED, hospital, hospice, and opiates and in chemotherapy toxicity from 1994 to 2003 (P < .001 for each). The correlations between the benchmark measures were generally low, which suggested that each measure represented a fairly distinct dimension of end-of-life care. The highest correlations were seen between the measures of ED, hospital, and ICU use (0.40 to 0.50). In both the retrospective and prospective cohorts, the opiate measures had low correlations with the other benchmarks (< 0.15). The chemotherapy toxicity measure was moderately correlated with the hospitalization and ICU benchmarks in the prospective cohort (0.39 and 0.50, respectively), but they had lower correlations in the retrospective cohort (0.13 and 0.17, respectively).
Measures of Opioid Use and Other Benchmarks
lists the association of physician and hospital characteristics on selected benchmarks for the different cohorts after adjustment for patient characteristics. Although the magnitude of the effects of physician and hospital characteristics on the receipt of the benchmark measures varied among cohorts, we found several similar patterns of association. Care from a medical oncologist was positively associated with the receipt of chemotherapy (both cohorts), opiates (both cohorts), chemotherapy toxicity (prospective cohort only), and use of hospice (both cohorts). The practice type of the treating oncologist also was associated with several of the benchmarks. For example, patients who were cared for by oncologists in small, solo practices were more likely to receive chemotherapy (retrospective cohort) and to lack hospice (both cohorts) than patients who received care in a group practice. Patients of hospital-based oncologists were less likely to receive chemotherapy (retrospective cohort) or opiates (retrospective cohort) than those who were cared for in a group practice. Patients who received care in a nonteaching hospital were less likely to receive opiates (both cohorts) and hospice (retrospective cohort) and were more likely to receive chemotherapy (both cohorts) and to have toxicity (prospective cohort) compared with those who were cared for in a teaching hospital.
Association of Physician and Hospital Characteristics With Measures of Opioid Use and Selected Benchmarks