BACKGROUND: Gender differences in health care utilization in older Americans may be confounded by nursing home residence. Medicare data contain several files that can be used to create a measure of nursing home residence, but prior work has not addressed which best account for potential confounding. Simpson's paradox occurs when aggregated data support a different conclusion from what the disaggregated data show. We describe such a paradox that appeared when we sharpened our definition of "nursing home residence" while examining gender differences in Medicare utilization at the end of life. METHODS: To understand gender-specific health care utilization at the end of life, we conducted a retrospective analysis of a national random sample of Medicare beneficiaries aged 66 or older who died in 2001 with Parts A and B data for 18 months before death. We sought to associate each of total hospital days and costs during the final 6 months of life with numbers of primary care physician visits in the 12 preceding months. In addition to demographics, comorbidities, and geography, "nursing home residence" was a potential confounder, which we imputed in two ways: 1) from skilled nursing facility bills in the Part A Medicare Provider Analysis and Review (MedPAR) file; and 2) from Berenson-Eggers-Type-of-Service codes indicating widely spaced doctor visits in nursing homes obtained from Medicare's carrier file. CONCLUSION: Gender differences in Medicare utilization are strongly confounded by nursing home resident status, which can be imputed well from Medicare's carrier file, but not MedPAR. Inc. All rights reserved.

BACKGROUND: Racial and ethnic minorities generally receive fewer medical interventions than whites, but racial and ethnic patterns in Medicare expenditures and interventions may be quite different at life's end. METHODS: Based on a random, stratified sample of Medicare decedents (N = 158 780) in 2001, we used regression to relate differences in age, sex, cause of death, total morbidity burden, geography, life-sustaining interventions (eg, ventilators), and hospice to racial and ethnic differences in Medicare expenditures in the last 6 months of life. RESULTS: In the final 6 months of life, costs for whites average $20,166; blacks, $26,704 (32% more); and Hispanics, $31,702 (57% more). Similar differences exist within sexes, age groups, all causes of death, all sites of death, and within similar geographic areas. Differences in age, sex, cause of death, total morbidity burden, geography, socioeconomic status, and hospice use account for 53% and 63% of the higher costs for blacks and Hispanics, respectively. While whites use hospice most frequently (whites, 26%; blacks, 20%; and Hispanics, 23%), racial and ethnic differences in end-of-life expenditures are affected only minimally. However, fully 85% of the observed higher costs for nonwhites are accounted for after additionally modeling their greater end-of-life use of the intensive care unit and various intensive procedures (such as, gastrostomies, used by 10.5% of blacks, 9.1% of Hispanics, and 4.1% of whites). CONCLUSIONS: At life's end, black and Hispanic decedents have substantially higher costs than whites. More than half of these cost differences are related to geographic, sociodemographic, and morbidity differences. Strikingly greater use of life-sustaining interventions accounts for most of the rest.

BACKGROUND: Medical care at the end of life is often expensive and ineffective. OBJECTIVE: To explore associations between primary care and hospital utilization at the end of life. DESIGN: Retrospective analysis of Medicare data. We measured hospital utilization during the final 6 months of life and the number of primary care physician visits in the 12 preceding months. Multivariate cluster analysis adjusted for the effects of demographics, comorbidities, and geography in end-of-life healthcare utilization. SUBJECTS: National random sample of 78,356 Medicare beneficiaries aged 66+ who died in 2001. Non-whites were over-sampled. All subjects with complete Medicare data for 18 months prior to death were retained, except for those in the End Stage Renal Disease program. MEASUREMENTS: Hospital days, costs, in-hospital death, and presence of two types of preventable hospital admissions (Ambulatory Care Sensitive Conditions) during the final 6 months of life. RESULTS: Sample characteristics: 38% had 0 primary care visits; 22%, 1-2; 19%, 3-5; 10%, 6-8; and 11%, 9+ visits. More primary care visits in the preceding year were associated with fewer hospital days at end of life (15.3 days for those with no primary care visits vs. 13.4 for those with > or = 9 visits, P < 0.001), lower costs ($24,400 vs. $23,400, P < 0.05), less in-hospital death (44% vs. 40%, P < 0.01), and fewer preventable hospitalizations for those with congestive heart failure (adjusted odds ratio, aOR = 0.82, P < 0.001) and chronic obstructive pulmonary disease (aOR = 0.81, P = 0.02). CONCLUSIONS: Primary care visits in the preceding year are associated with less, and less costly, end-of-life hospital utilization. Increased primary care access for Medicare beneficiaries may decrease costs and improve quality at the end of life.