Excess mortality following hip fracture: the role of underlying health status

We evaluated the long-term excess mortality associated with hip fracture, using prospectively collected data on pre-fracture health and function from a nationally representative sample of U.S. elders. Although mortality was elevated for the first six months following hip fracture, we found no evidence of long-term excess mortality.

INTRODUCTION

The long-term excess mortality associated with hip fracture remains controversial.

METHODS

To assess the association between hip fracture and mortality, we used prospectively collected data on pre-fracture health and function from a representative sample of U.S. elders in the Medicare Current Beneficiary Survey (MCBS) to perform survival analyses with time-varying covariates.

RESULTS

Among 25,178 MCBS participants followed for a median duration of 3.8 years, 730 sustained a hip fracture during follow-up. Both early (within 6 months) and subsequent mortality showed significant elevations in models adjusted only for age, sex and race. With additional adjustment for pre-fracture health status, functional impairments, comorbid conditions and socioeconomic status, however, increased mortality was limited to the first six months after fracture (hazard ratio [HR]: 6.28, 95% CI: 4.82, 8.19). No increased mortality was evident during subsequent follow-up (HR: 1.04, 95% CI: 0.88, 1.23). Hip-fracture-attributable population mortality ranged from 0.5% at age 65 among men to 6% at age 85 among women.

CONCLUSIONS

Hip fracture was associated with substantially increased mortality, but much of the short-term risk and all of the long-term risk was explained by the greater frailty of those experiencing hip fracture.

The burden of prevention: downstream consequences of Pap smear testing in the elderly

CONTEXT

Although cervical cancer is an unusual cause of death among women 65 and older, most elderly women in the US report continuing to undergo periodic Pap smear screening.

OBJECTIVE

To describe the incidence of Pap smears and downstream testing among elderly women.

SETTING

Claims-based analysis of female Medicare enrollees age 65 and older.

METHODS

Using three years of Medicare Part B 5% Files (1995-1997), we differentiated between women undergoing screening Pap smears and those undergoing Pap smears for surveillance of previous abnormalities or Pap smear follow-up. We determined the proportion of elderly women undergoing Pap smear testing and rates of downstream testing and procedures after an initial Pap smear.

RESULTS

Four million female Medicare beneficiaries over 65 years underwent Pap smear testing between 1995 and 1997, representing 25% of the eligible population. After adjusting for underbilling for Pap smears under Medicare, 43% of women over 65 are estimated to have undergone Pap smear testing during the 3-year period. The large majority (90%) of Pap smears were for screening, while 10% were done for surveillance or follow-up. For every 1000 women with a screening Pap smear, 39 had at least one downstream intervention within eight months of the initial Pap smear, including seven women who underwent colposcopy and two women who had other surgical procedures. Rates of downstream interventions were considerably higher for women undergoing Pap smear follow-up (302 per 1000 with at least one downstream intervention), and surveillance of previous abnormalities (209 per 1000 with a downstream intervention).

CONCLUSION

Cervical cancer screening is widespread among elderly American women, and follow-up testing is not uncommon, particularly among the ten percent of women who appear to be in a cycle of repeated testing. This substantial volume of testing occurs despite the rarity of cervical cancer deaths and unknown benefits of screening in this age group.

Are neonatal intensive care resources located according to need? Regional variation in neonatologists, beds, and low birth weight newborns

OBJECTIVE

Despite marked growth in neonatal intensive care during the past 30 years, it is not known if neonatologists and beds are preferentially located in regions with greater newborn risk. This study reports the relationship between regional measures of intensive care capacity and low birth weight infants using newly developed market-based regions of neonatal intensive care.

DESIGN

Cross-sectional small-area analysis of 246 neonatal intensive care regions (NICRs).

DATA SOURCES

1996 American Medical Association and American Osteopathic Association masterfiles data of clinically active neonatologists; 1999 American Academy of Pediatrics Section on Perinatal Pediatrics survey of directors of neonatal intensive care units in the United States with 100% response rate; 1995 linked birth/death data.

RESULTS

The number of total births per neonatologist across NICRs ranged from 390 to 8197 (median: 1722) and the number of total births per intensive care bed ranged from 72 to 1319 (median: 317). The associations between capacity measures and low birth weight rates across NICRs were statistically significant but negligible (R(2): 0.04 for neonatologists; 0.05 for beds). NICRs in the quintile with the greatest neonatologist capacity (average of only 863 births per neonatologist) had very low birth weight (VLBW) rates of 1.5% while those in the quintile of lowest neonatologist capacity (average of 3718 births per neonatologist) had VLBW rates of 1.3%; a similar lack of meaningful difference in VLBW rates was noted across quintiles of intensive care bed capacity. Including midlevel providers and intermediate care beds to the analyses did not alter the findings.

CONCLUSIONS

Neonatal intensive care capacity is not preferentially located in regions with greater newborn need as measured by low birth weight rates. Whether greater capacity affords benefits to the newborns remains unknown.

The development of a survey instrument for community health improvement

OBJECTIVE

To develop a survey instrument that could be used both to guide and evaluate community health improvement efforts.

DATA SOURCES/STUDY SETTING

A randomized telephone survey was administered to a sample of about 250 residents in two communities in Lehigh Valley, Pennsylvania in the fall of 1997.

METHODS

The survey instrument was developed by health professionals representing diverse health care organizations. This group worked collaboratively over a period of two years to (1) select a conceptual model of health as a foundation for the survey; (2) review relevant literature to identify indicators that adequately measured the health constructs within the chosen model; (3) develop new indicators where important constructs lacked specific measures; and (4) pilot test the final survey to assess the reliability and validity of the instrument.

PRINCIPAL FINDINGS

The Evans and Stoddart Field Model of the Determinants of Health and Well-Being was chosen as the conceptual model within which to develop the survey. The Field Model depicts nine domains important to the origins and production of health and provides a comprehensive framework from which to launch community health improvement efforts. From more than 500 potential indicators we identified 118 survey questions that reflected the multiple determinants of health as conceptualized by this model. Sources from which indicators were selected include the Behavior Risk Factor Surveillance Survey, the National Health Interview Survey, the Consumer Assessment of Health Plans Survey, and the SF-12 Summary Scales. The work group developed 27 new survey questions for constructs for which we could not locate adequate indicators. Twenty-five questions in the final instrument can be compared to nationally published norms or benchmarks. The final instrument was pilot tested in 1997 in two communities. Administration time averaged 22 minutes with a response rate of 66 percent. Reliability of new survey questions was adequate. Face validity was supported by previous findings from qualitative and quantitative studies.

CONCLUSIONS

We developed, pilot tested, and validated a survey instrument designed to provide more comprehensive and timely data to communities for community health assessments. This instrument allows communities to identify and measure critical domains of health that have previously not been captured in a single instrument.

Hospice use in Medicare managed care and fee-for-service systems

OBJECTIVE

To examine whether patterns of hospice use by older Medicare beneficiaries are consistent with the differing financial incentives in Medicare managed care (MC) and fee-for-service (FFS) settings. Specifically, are use patterns consistent with incentives that might encourage hospice use for MC enrollees and discourage hospice use for FFS enrollees?

STUDY DESIGN

One-year study of hospice use by Medicare beneficiaries dying in 1996.

PATIENTS AND METHODS

Medicare enrollment and hospice administrative data were used to examine hospice use before death for all elderly individuals residing in 100 US counties with high MC enrollment in 1996. Age-, sex-, and race-adjusted rate of hospice use and length of stay in hospice are compared between FFS and MC enrollees across and within (when possible) the 100 counties.

RESULTS

Rates of hospice use were significantly higher for MC enrollees than for FFS enrollees (26.6 vs 17.0 per 100 deaths; P < .001). These differences persisted within age, sex, and race groups but were not related to area MC enrollment rate or the amount of money paid to managed care organizations. Age-, sex-, and race-adjusted differences were observed in 94 of 100 counties. Length of stay in hospice was marginally longer for MC enrollees than for FFS enrollees (median, 24 vs 21 days; P < .0001).

CONCLUSIONS

System of care is an important determinant of hospice use in the elderly Medicare population.

The uneven landscape of newborn intensive care services: variation in the neonatology workforce

CONTEXT

In the past 30 years, the number of neonatologists has increased while total births have remained nearly constant. It is not known how equitably this expanded workforce is distributed.

OBJECTIVE

To determine the geographic distribution of neonatologists in the United States.

DATA SOURCES

1996 American Medical Association physician masterfiles; 1999 survey of all U.S. neonatal intensive care units; 1995 American Hospital Association hospital survey; and 1995 U.S. vital records.

MEASURES

The number of neonatologists and neonatal mid-level providers per live birth within 246 market-based regions.

RESULTS

The neonatology workforce varied substantially across neonatal intensive care regions. The number of neonatologists per 10,000 live births ranged from 1.2 to 25.6 with an interquintile range of 3.5 to 8.5. The weakly positive correlation between neonatologists and neonatal mid-level providers per live birth is not consistent with substitution of neonatal mid-level providers for neonatologists (Spearman rank-correlation coefficient, 0.17; P < 0.01). There was no difference in the percentage of neonatal fellows in the lowest and highest workforce quintile (14% vs. 16%) or in the percentage of neonatologists engaged predominantly in research, teaching, or administration (14% in lowest and highest quintiles).

CONCLUSIONS

The regional supply of neonatologists varies dramatically and cannot be explained by the substitution of neonatal mid-level providers or by the presence of academic medical centers. Further research is warranted to understand whether neonatal intensive care resources are located in accordance with risk and whether more resources improve newborn outcomes.

Associations among hospital capacity, utilization, and mortality of US Medicare beneficiaries, controlling for sociodemographic factors

OBJECTIVE

To explore whether geographic variations in Medicare hospital utilization rates are due to differences in local hospital capacity, after controlling for socioeconomic status and disease burden, and to determine whether greater hospital capacity is associated with lower Medicare mortality rates.

DATA SOURCES/STUDY SETTING

The study population: a 20 percent sample of 1989 Medicare enrollees. Measures of resources were based on a national small area analysis of 313 Hospital Referral Regions (HRR). Demographic and socioeconomic data were obtained from the 1990 U.S. Census. Measures of local disease burden were developed using Medicare claims files.

STUDY DESIGN

The study was a cross-sectional analysis of the relationship between per capita measures of hospital resources in each region and hospital utilization and mortality rates among Medicare enrollees. Regression techniques were used to control for differences in sociodemographic characteristics and disease burden across areas.

DATA COLLECTION/EXTRACTION METHODS

Data on the study population were obtained from Medicare enrollment (Denominator File) and hospital claims files (MedPAR) and U.S. Census files.

PRINCIPAL FINDINGS

The per capita supply of hospital beds varied by more than twofold across U.S. regions. Residents of areas with more beds were up to 30 percent more likely to be hospitalized, controlling for ecologic measures of socioeconomic characteristics and disease burden. A greater proportion of the population was hospitalized at least once during the year in areas with more beds; death was also more likely to take place in an inpatient setting. All effects were consistent across racial and income groups. Residence in areas with greater levels of hospital resources was not associated with a decreased risk of death.

CONCLUSIONS

Residence in areas of greater hospital capacity is associated with substantially increased use of the hospital, even after controlling for socioeconomic characteristics and illness burden. This increased use provides no detectable mortality benefit.

Maneuvering the mundane minefield: a practical guide to legal opinions in healthcare transactions

This Article examines the multitude of issues presented when attorneys prepare legal opinions for health law transactions. The authors analyze the two major pieces of guidance for the drafting of such opinions, and offer practical guidance and checklists for the preparation of such opinions.

The association between for-profit hospital ownership and increased Medicare spending

BACKGROUND AND METHODS

The rate of conversion to for-profit ownership of hospitals has recently increased in the United States, with uncertain implications for health care costs. We compared total per capita Medicare spending in areas served by for-profit and not-for-profit hospitals. We used American Hospital Association data to categorize U.S. hospital service areas as for-profit (meaning that all beds in the area were in for-profit hospitals), not-for-profit (all beds were in not-for-profit hospitals), or mixed in 1989, 1992, and 1995. We then used data from the Continuous Medicare History Sample to calculate the 1989, 1992, and 1995 spending rates in each area, adjusting for other characteristics known to influence spending: age, sex, race, region of the United States, percentage of population living in urban areas, Medicare mortality rate, number of hospitals, number of physicians per capita, percentage of beds in hospitals affiliated with medical schools, percentage of beds in hospitals belonging to hospital chains, and percentage of Medicare beneficiaries enrolled in health maintenance organizations.

RESULTS

Adjusted total per capita Medicare spending in the 208 areas where all hospitals remained under for-profit ownership during the study years was greater than in the 2860 areas where all hospitals remained under not-for-profit ownership ($4,006 vs. $3,554 in 1989, $4,243 vs. $3,841 in 1992, and $5,172 vs. $4,440 in 1995; P<0.001 for each comparison). Mixed areas had intermediate spending rates. Spending in for-profit areas was greater than in not-for-profit areas in each category of service examined: hospital services, physicians' services, home health care, and services at other facilities. The greatest increases in per capita spending between 1989 and 1995 were for hospital services (a mean increase of $395 in for-profit areas and $283 in not-for-profit areas, P=0.03 for the comparison between for-profit and not-for-profit areas) and home health care (an increase of $457 in for-profit areas and $324 in not-for-profit areas, P<0.001). Between 1989 and 1995, spending in the 33 areas where all hospitals converted from not-for-profit to for-profit ownership grew more rapidly than in the 2860 areas where all hospitals remained under not-for-profit ownership ($1,295 vs. $866, P=0.03).

CONCLUSIONS

Both the rates of per capita Medicare spending and the increases in spending rates were greater in areas served by for-profit hospitals than in areas served by not-for-profit hospitals.

Geographic barriers to child health services in rural northern New England: 1980 to 1989

Despite substantial recent increases in the number of rural physicians, it is unknown whether rural children still face significant barriers to medical care. To address this question, we determined travel times in 1980 and in 1989 to child health services for the rural pediatric population of northern New England--the area with the highest per-capita primary care physician supply of any non-metropolitan region in the United States. The study population in 1989 included 363,443 children living in 936 nonmetropolitan towns. The study revealed important spatial relationships in health service supply and demand not identified using other methods of assessing physician availability. Although travel times to physicians decreased slightly during the decade, we found that 15.5 percent of the children in our population were more than 30 minutes from pediatricians in 1989, and travel time to emergency rooms was more than 30 minutes for 9.9 percent of the children. In contrast, only 1.8 percent of children faced excessive travel times to family/general practitioners. While towns with pediatricians were likely to also have a family physician or an emergency room, the majority of towns with family physicians had neither a pediatrician nor an emergency room. Towns with poor geographic access to pediatricians and emergency rooms had low population densities and were distant from metropolitan areas. The analysis indicates that even in rural areas of high physician supply, access to pediatricians and emergency rooms for many children remains limited, and family physicians are the dominant medical providers for children.(ABSTRACT TRUNCATED AT 250 WORDS)

Effect of hospital volume on in-hospital mortality with pancreaticoduodenectomy

BACKGROUND

Reports of better results at national referral centers than at low-volume community hospitals have prompted calls for regionalizing pancreaticoduodenectomy (the Whipple procedure). We examined the relationship between hospital volume and mortality with this procedure across all US hospitals.

METHODS

Using information from the Medicare claims database, we performed a national cohort study of 7229 Medicare patients more than 65 years old undergoing pancreaticoduodenectomy between 1992 and 1995. We divided the study population into approximate quartiles according to the hospital's average annual volume of pancreaticoduodenectomies in Medicare patients: very low (< 1/y), low (1-2/y), medium (2-5/y), and high (5+/y). Using multivariate logistic regression to account for potentially confounding patient characteristics, we examined the association between institutional volume and in-hospital mortality, our primary outcome measure.

RESULTS

More than 50% of Medicare patients a undergoing pancreaticoduodenectomy received care at hospitals performing fewer than 2 such procedures per year. In-hospital mortality rates at these low- and very-low-volume hospitals were 3- to 4-fold higher than at high-volume hospitals (12% and 16%, respectively, vs 4%, P < .001). Within the high-volume quartile, the 10 hospitals with the nation's highest volumes had lower mortality rates than the remaining high-volume centers (2.1% vs 6.2%, P < .01). The strong association between institutional volume and mortality could not be attributed to patient case-mix differences or referral bias.

CONCLUSIONS

Although volume-outcome relationships have been reported for many complex surgical procedures, hospital experience is particularly important with pancreaticoduodenectomy. Patients considering this procedure should be given the option of care at a high-volume referral center.

How well does a single question about health predict the financial health of Medicare managed care plans?

CONTEXT

Responses to simple questions that predict subsequent health care utilization are of interest to both capitated health plans and the payer.

OBJECTIVE

To determine how responses to a single question about general health status predict subsequent health care expenditures.

DESIGN

Participants in the 1992 Medicare Current Beneficiary Survey were asked the following question: "In general, compared to other people your age, would you say your health is: excellent, very good, good, fair or poor?" To obtain each participant's total Medicare expenditures and number of hospitalizations in the ensuing year, we linked the responses to this question with data from the 1993 Medicare Continuous History Survey.

SAMPLE

Nationally representative sample of 8775 noninstitutionalized Medicare beneficiaries 65 years of age and older.

MAIN OUTCOME MEASURES

Annual age- and sex-adjusted Medicare expenditures and hospitalization rates.

RESULTS

Eighteen percent of the beneficiaries rated their health as excellent, 56% rated it as very good or good, 17% rated it as fair, and 7% rated it as poor. Medicare expenditures had a marked inverse relation to self-assessed health ratings. In the year after assessment, age- and sex-adjusted annual expenditures varied fivefold, from $8743 for beneficiaries rating their health as poor to $1656 for beneficiaries rating their health as excellent. Hospitalization rates followed the same pattern: Respondents who rated their health as poor had 675 hospitalizations per 1000 beneficiaries per year compared with 136 per 1000 for those rating their health as excellent.

CONCLUSIONS

The response to a single question about general health status strongly predicts subsequent health care utilization. Self-reports of fair or poor health identify a group of high-risk patients who may benefit from targeted interventions. Because the current Medicare capitation formula does not account for health status, health plans can maximize profits by disproportionately enrolling beneficiaries who judge their health to be good. However, they are at a competitive disadvantage if they enroll beneficiaries who view themselves as sick.

Avoiding the unintended consequences of growth in medical care: how might more be worse?

The United States has experienced dramatic growth in both the technical capabilities and share of resources devoted to medical care. While the benefits of more medical care are widely recognized, the possibility that harm may result from growth has received little attention. Because harm from more medical care is unexpected, findings of harm are discounted or ignored. We suggest that such findings may indicate a more general problem and deserve serious consideration. First, we delineate 2 levels of decision making where more medical care may be introduced: (1) decisions about whether or not to use a discrete diagnostic or therapeutic intervention and (2) decisions about whether to add system capacity, eg, the decision to purchase another scanner or employ another physician. Second, we explore how more medical care at either level may lead to harm. More diagnosis creates the potential for labeling and detection of pseudodisease--disease that would never become apparent to patients during their lifetime without testing. More treatment may lead to tampering, interventions to correct random rather than systematic variation, and lower treatment thresholds, where the risks outweigh the potential benefits. Because there are more diagnoses to treat and more treatments to provide, physicians may be more likely to make mistakes and to be distracted from the issues of greatest concern to their patients. Finally, we turn to the fundamental challenge--reducing the risk of harm from more medical care. We identify 4 ways in which inadequate information and improper reasoning may allow harmful practices to be adopted-a constrained model of disease, excessive extrapolation, a missing level of analysis, and the assumption that more is better.

When should this patient be seen again?

CONTEXT

The decision about when to ask a patient to return to the clinic for his or her next visit is common to all outpatient encounters in longitudinal care. It directly affects provider workloads and has a potentially great impact on health care costs and outcomes.

GENERAL QUESTION

What are the effects of lengthening or shortening revisit intervals (the recommended period between one visit and the next) on health status and health care costs?

SPECIFIC RESEARCH CHALLENGE

How can we change the average revisit interval while preserving provider input for individual patients?

PROPOSED APPROACH

Patients could be randomly assigned to either short or long revisit intervals. So that provider input would be preserved, providers would select from among three discrete categories of revisit intervals: near-term (1 to 2 months); intermediate-term (2 to 4 months); and long-term (4 to 8 months). On the basis of randomization, patients would receive appointments at either the lower or the upper bound of the category selected.

POTENTIAL DIFFICULTIES

Because blinding would be almost impossible, providers might "game" randomization at subsequent visits.

ALTERNATE APPROACHES

A comparison of shorter and longer revisit intervals might be achieved with less direct approaches. In one such approach, patients would be randomly assigned to 1) having an appointment made immediately after the initial visit or 2) calling back for an appointment according to the interval recommended by the provider. In another approach, patient panel size would be held constant and providers would be randomly assigned to either an increased or a reduced number of clinic sessions.

Capitation among Medicare beneficiaries

CONTEXT

The Medicare program has promoted capitation as a way to contain costs. About 15% of Medicare beneficiaries nationwide are currently under capitation, but tremendous regional variation exists.

PRACTICE PATTERN EXAMINED

The proportion of Medicare beneficiaries who have enrolled in risk-contract plans in individual states and in the 25 largest metropolitan areas in the United States.

DATA SOURCE

Health Care Financing Administration data files.

RESULTS

Medicare beneficiaries are most likely to be under capitation in Arizona (38%) and California (37%). Eight other states have capitation rates greater than 20%: Colorado, Florida, Rhode Island, Oregon, Washington, Pennsylvania, Massachusetts, and Nevada. Thirty states, largely in the Great Plains area and the southern United States, have capitation rates less than 10%. Four major metropolitan areas have market penetration rates greater than 40%: San Bernardino, California; San Diego, California; Phoenix, Arizona; and Miami, Florida. Little penetration exists outside of metropolitan areas.

CONCLUSION

Capitation in Medicare is a regional and predominantly an urban phenomenon.

Variation profiles of common surgical procedures

BACKGROUND

Rates of many surgical procedures vary widely across both large and small geographic regions. Although variation in health care use has long been described, few studies have systematically compared variation profiles across surgical procedures. The goal of this study was to examine current patterns of regional variation in the rates of common surgical procedures.

METHODS

The study population consisted of patients enrolled in Medicare in 1995, excluding those enrolled in risk-bearing health maintenance organizations. Patients ranged in age from 65 to 99 years. Using data from hospital discharge abstracts, we calculated rates of 11 common inpatient procedures for each of 306 US hospital referral regions (HRRs). To assess the relative variability of each procedure, we determined the number of low and high outlier regions (HRRs with rates < 50% or > 150% the national average) and the ratio of highest to lowest HRR rates.

RESULTS

Procedures differed markedly in their variability. Rates of hip fracture repair, resection for colorectal cancer, and cholecystectomy varied only 1.9- to 2.9-fold across HRRs (0, 0, and 4 outlier regions, respectively). Coronary artery bypass grafting, transurethral prostatectomy, mastectomy, and total hip replacement had intermediate variation profiles, varying 3.5- to 4.7-fold across regions (8, 10, 16, and 17 outlier regions, respectively). Lower extremity revascularization, carotid endarterectomy, back surgery, and radical prostatectomy had the highest variation profiles, varying 6.5- to 10.1-fold across HRRs (25, 32, 39, and 56 outlier regions, respectively).

CONCLUSIONS

Although the use of many surgical procedures varies widely across geographic areas, rates of "discretionary" procedures are most variable. To avoid potential overuse or underuse, efforts to increase consensus in clinical decision making should focus on these high variation procedures.

Influence of patient preferences and local health system characteristics on the place of death. SUPPORT Investigators. Study to Understand Prognoses and Preferences for Risks and Outcomes of Treatment

OBJECTIVE

To examine the degree to which variation in place of death is explained by differences in the characteristics of patients, including preferences for dying at home, and by differences in the characteristics of local health systems.

DESIGN

We drew on a clinically rich database to carry out a prospective study using data from the observational phase of the Study to Understand Prognoses and Preferences for Outcomes and Risks of Treatments (SUPPORT component). We used administrative databases for the Medicare program to carry out a national cross-sectional analysis of Medicare enrollees place of death (Medicare component).

SETTING

Five teaching hospitals (SUPPORT); All U.S. Hospital Referral Regions (Medicare).

STUDY POPULATIONS

Patients dying after the enrollment hospitalization in the observational phase of SUPPORT for whom place of death and preferences were known. Medicare beneficiaries who died in 1992 or 1993.

MAIN OUTCOME MEASURES

Place of death (hospital vs non-hospital).

RESULTS

In SUPPORT, most patients expressed a preference for dying at home, yet most died in the hospital. The percent of SUPPORT patients dying in-hospital varied by greater than 2-fold across the five SUPPORT sites (29 to 66%). For Medicare beneficiaries, the percent dying in-hospital varied from 23 to 54% across U.S. Hospital Referral Regions (HRRs). In SUPPORT, variations in place of death across site were not explained by sociodemographic or clinical characteristics or patient preferences. Patient level (SUPPORT) and national cross-sectional (Medicare) multivariate models gave consistent results. The risk of in-hospital death was increased for residents of regions with greater hospital bed availability and use; the risk of in-hospital death was decreased in regions with greater nursing home and hospice availability and use. Measures of hospital bed availability and use were the most powerful predictors of place of death across HRRs.

CONCLUSIONS

Whether people die in the hospital or not is powerfully influenced by characteristics of the local health system but not by patient preferences or other patient characteristics. These findings may explain the failure of the SUPPORT intervention to alter care patterns for seriously ill and dying patients. Reforming the care of dying patients may require modification of local resource availability and provider routines.

Diagnostic testing following screening mammography in the elderly

BACKGROUND

To provide some sense of the general frequency and timing of diagnostic testing following screening mammography in the United States, we investigated the experience of women screened in the Medicare population.

METHODS

By use of Medicare's National Claims History System, we identified a cohort (n=23172) of women 65 years old or older screened during the period from January 1, 1995, through April 30, 1995, and tracked each woman over the subsequent 8 months for the performance of additional breast imaging and biopsy procedures. Using two claims-based definitions for newly detected breast cancer, we also estimated the positive predictive value of screening mammography.

RESULTS

For every 1000 women aged 65-69 years who underwent screening, 85 (95% confidence interval [CI]=79-91) had follow-up testing in the subsequent 8 months; 76 (95% CI=71-82) had additional breast imaging, and 23 (95% CI=20-26) had biopsy procedures. Corresponding numbers for women aged 70 years or more were similar. Some women underwent repeated examinations; 13% of those receiving diagnostic mammograms had more than one; 11% of those undergoing biopsy procedures had more than one. About half of the women who underwent a biopsy had the procedure more than 3 weeks after the imaging test upon which the decision to perform a biopsy was presumably made. The estimated positive predictive value of an abnormal screening mammogram (defined as a mammogram that engendered additional testing) was 0.08 (95% CI=0.06-0.10) for women aged 65-69 years and 0.14 (95% CI=0.12-0.16) for women aged 70 years or more.

CONCLUSION

Additional testing is a frequent consequence of screening mammography and may require a considerable period of time to come to closure. The need for additional testing, however, is weakly predictive of cancer.

Variation in carotid endarterectomy mortality in the Medicare population: trial hospitals, volume, and patient characteristics

CONTEXT

The North American Symptomatic Carotid Endarterectomy Trial (NASCET) and the Asymptomatic Carotid Atherosclerosis Study (ACAS) demonstrated the efficacy of carotid endarterectomy (CEA) in reducing the risk of stroke and death in selected patients when surgery was performed in institutions whose participation depended on demonstrated excellence. Thirty-day mortality rates in the trials were very low: 0.6% in NASCET and 0.1% in ACAS.

OBJECTIVE

To assess perioperative mortality among Medicare patients undergoing CEA in all nonfederal institutional settings.

DESIGN

Retrospective national cohort study.

SETTING AND PATIENTS

All 113300 Medicare patients undergoing CEA during 1992 and 1993 in "trial hospitals" (those participating in NASCET and ACAS, n=86) and "nontrial hospitals" (all other nonfederal institutions performing CEAs, n=2613). Nontrial hospitals were stratified into terciles based on volume of CEAs performed.

MAIN OUTCOME MEASURES

Crude and adjusted perioperative (30 day) mortality rates.

RESULTS

The perioperative mortality rate was 1.4% (95% confidence interval [CI], 1.2%-1.7%) at trial hospitals; mortality in nontrial hospitals was higher: 1.7% (95% CI, 1.6%-1.8%) (high volume); 1.9% (95% CI, 1.7%-2.1 %) (average volume); 2.5% (95% CI, 2.0%-2.9%) (low volume); (P for trend, <.001). In multivariate modeling, patients undergoing their procedures at trial hospitals had a mortality risk reduction of 15% (95% CI, 0%-31%) compared with high-volume nontrial hospitals, 25% (95% CI, 7%-40%) compared with average-volume hospitals, and 43% (95% CI, 25%-56%) compared with low-volume hospitals (P for trend, <.001).

CONCLUSION

Medicare patients' perioperative mortality following CEA is substantially higher than that reported in the trials, even in those institutions that participated in the randomized studies. Caution is advised in translating the efficacy of carefully controlled studies of CEA to effectiveness in everyday practice.

Managing conflicts over limited resources

Many conflicts in health care, such as disputes over physician compensation or plan coverage decisions, recur frequently and can be viewed as processes of production. This article proposes a model of the negotiation process and suggests an approach to the management and improvement of common conflicts over limited resources.

Perceived adequacy of tangible social support and health outcomes in patients with coronary artery disease

OBJECTIVE

Health outcomes of patients with chronic disease might be influenced by assistance from others in performing daily activities. We examined whether perceived adequacy of such tangible support was associated with prognosis in a cohort of patients with coronary artery disease.

DESIGN

Longitudinal cohort study.

SETTING/PARTICIPANTS

In spring 1993, a cohort of 1,468 patients with chronic artery disease was identified using claims data. The cohort consisted of all surviving residents of Manitoba, Canada, who had been hospitalized for acute myocardial infarction from 1991 to 1992: 820 patients completed the initial survey, and 734 completed a follow-up survey approximately 1 year later.

MEASUREMENTS AND MAIN RESULTS

Adequacy of tangible support was assessed by asking if respondents needed help at home because of health problems, and whether these needs were met. We examined the association between perceived adequacy of tangible support and health outcomes at 1 year (mortality, physical function). Of 820 participants, 74% perceived no need for help, 13% had sufficient help, 9% needed more help, and 5% needed much more help; 31 patients died during follow-up. After adjustment for age and initial health status, odds ratios (95% confidence interval) for death were: sufficient help 1.8 (0.61, 5.8); need more help 3.2 (1.1, 9.4); and need much more help 6.5 (2.0, 21.6) compared with respondents with no perceived need. Decline in physical function was also linearly related to perceiving less-adequate tangible support. Sensitivity analyses indicated it is highly improbable that results were due to selection bias.

CONCLUSIONS

Perceived lack of needed assistance was related to mortality and to decline in physical functioning. Adequacy of tangible support was an important prognostic factor for these patients with coronary artery disease and may be a determinant of health outcomes.

Treatment and health outcomes of women and men in a cohort with coronary artery disease

BACKGROUND

Women with coronary artery disease are treated differently than men. Although mortality has been studied, functional outcomes for women and men have not been prospectively compared.

METHODS

The Manitoba Health Reform Impact Study used hospital databases to identify all residents aged 45 years and older in Manitoba who were hospitalized for a myocardial infarction between October 1, 1991, and September 30, 1992. Cohort members were interviewed twice, an average of 16 and 25 months after hospitalization. Baseline and follow-up measures included treatments (eg, physician visits, diagnostic testing, revascularization, and cardiac medications), physical health status (physical component summary [PCS] score derived from the Medical Outcomes Study Short Form 36), reinfarction, and mortality.

RESULTS

Of the 820 patients who completed the initial survey, 31 died during the follow-up period, and 734 completed the follow-up survey. Data were complete for the primary outcome (PCS score) and all relevant covariates for the 677 patients who were included in this study Women constituted 34% of this cohort. Although women had more physician visits during follow-up, they were less likely to have undergone treadmill testing or angiography (odds ratio, 0.68; 95% confidence interval, 0.46-0.99). Women were equally likely to report taking beta-adrenergic blocking agents, but were less likely than men to report the use of aspirin (odds ratio, 0.69; 95% confidence interval, 0.48-0.98). After adjusting for baseline differences in PCS scores, age, income, social supports, and the levels of angina and dyspnea, the PCS score for women declined by 1.4 points, while the score for men improved by 0.2 points (P = .03). During the follow-up period, reinfarction and mortality rates were low overall, but were not different in men and women.

CONCLUSIONS

In this cohort of patients with known coronary artery disease, we found less aggressive treatment of coronary artery disease and less use of aspirin among women than among men during 1 year of observation. After controlling for baseline differences, women with coronary artery disease experienced a more rapid decline in physical health status than did men during 1 year of follow-up.

The 3H-leucine tracer: its use in kinetic studies of plasma lipoproteins

3H-leucine administered as a bolus has been widely used as a tracer in kinetic investigations of protein synthesis and secretion. After intravenous injection, plasma specific radioactivity decays over several orders of magnitude during the first half-day, followed by a slow decay lasting a number of weeks that results from recycling of the leucine tracer as proteins are degraded and 3H-leucine reenters the plasma pool. In studies in which kinetic data are analyzed by mathematical compartmental modeling, plasma leucine activity is generally used as a forcing function to drive the input of 3H-leucine into the protein synthesis pathway. 3H-leucine is an excellent tracer during the initial hours of rapidly decreasing plasma activity; thereafter, reincorporation of recycled tracer into new protein synthesis obscures the tracer data from proteins with slower turnover rates. Thus, for proteins such as plasma albumin and apolipoprotein (apo) A-I, this tracer is unsatisfactory for measuring fractional catabolic (FCR) and turnover rates. By contrast, the kinetics of plasma very-low-density lipoprotein (VLDL)-apoB, a protein with a residence time of approximately 5 hours, are readily measured, since kinetic parameters of this protein can be determined by the time plasma leucine recycling becomes established. However, measurement of VLDL-apoB specific radioactivity extending up to 2 weeks provides further data on the kinetic tail of VLDL-apoB. Were plasma leucine a direct precursor for the leucine in VLDL-apoB, the kinetics of the plasma tracer should determine the kinetics of the protein. However, this is not the case, and the deviations from linearity are interpreted in terms of (1) the dilution of plasma leucine in the liver by unlabeled dietary leucine; (2) the recycling of hepatocellular leucine from proteins within the liver, where recycled cellular leucine does not equilibrate with plasma leucine; and (3) a "hump" in the kinetic data of VLDL-apoB, which we interpret to reflect recycling or retention of a portion of the apoB protein within the hepatocyte, with its subsequent secretion. Because hepatocellular tRNA is the immediate precursor for synthesis of these secretory proteins, its kinetics should be used as the forcing function to drive the modeling of this system. The VLDL-apoB tail contains the information needed to modify the plasma leucine data, to provide an appropriate forcing function when using 3H-leucine as a tracer of apolipoprotein metabolism. This correction is essential when using 3H-leucine as a tracer for measuring low-density lipoprotein (LDL)-apoB kinetics. The 3H-leucine tracer also highlights the importance of recognizing the difference between plasma and system residence times, the latter including the time the tracer resides within exchanging extravascular pools. The inability to determine these fractional exchange coefficients for apoA-I and albumin explains the failure of this tracer in kinetic studies of these proteins. For apoB-containing lipoproteins, plasma residence times are generally determined, and these measurements can be made satisfactorily with 3H-leucine.

Where do elderly veterans obtain care for acute myocardial infarction: Department of Veterans Affairs or Medicare?

OBJECTIVE

To examine Department of Veterans Affairs (VA) and Medicare hospitalizations for elderly veterans with acute myocardial infarction (AMI), their use of cardiac procedures in both systems, and patient mortality.

DATA SOURCES

Merging of inpatient discharge abstracts obtained from VA Patient Treatment Files (PTF) and Medicare MedPAR Part A files.

STUDY DESIGN

A retrospective cohort study of male veterans 65 years or older who were prior users of the VA medical system (veteran-users) and who were initially admitted to a VA or Medicare hospital with a primary diagnosis of AMI at some time from January 1, 1988 through December 31, 1990 (N = 25,312). We examined the use of cardiac catheterization, coronary bypass surgery, and percutaneous transluminal coronary angioplasty in the 90 days after initial admission for AMI in both VA and Medicare systems, and survival at 30 days, 90 days, and one year. Other key measures included patient age, race, marital status, comorbidities, cardiac complications, prior utilization, and the availability of cardiac technology at the admitting hospital.

PRINCIPAL FINDINGS

More than half of veteran-users (54 percent) were initially hospitalized in a Medicare hospital when they suffered an AMI. These Medicare index patients were more likely to receive cardiac catheterization (OR 1.24, 95% C.I. 1.17-1.32), coronary bypass surgery (OR 2.01, 95% C.I. 1.83-2.20), and percutaneous transluminal coronary angioplasty (OR 2.56, 95% C.I. 2.30-2.85) than VA index patients. Small proportions of patients crossed over between systems of care for catheterization procedures (VA to Medicare = 3.3%, and Medicare to VA = 5.1%). Many VA index patients crossed over to Medicare hospitals to obtain bypass surgery (27.6 percent) or coronary angioplasty (12.1 percent). Mortality was not significantly different between veteran-users who were initially admitted to VA versus Medicare hospitals.

CONCLUSIONS

Dual-system utilization highlights the need to look at both systems of care when evaluating access, costs, and quality either in VA or in Medicare systems. Policy changes that affect access to and utilization of one system may lead to unpredictable results in the other.

Benchmarking the US physician workforce. An alternative to needs-based or demand-based planning

OBJECTIVE

To propose population-based benchmarking as an alternative to needs- or demand-based planning for estimating a reasonably sized, clinically active physician workforce for the United States and its regional health care markets.

DESIGN

Cross-sectional analysis of 1993 American Medical Association and American Osteopathic Association physician masterfiles.

POPULATION

The resident population of the 306 hospital referral regions in the United States.

MAIN OUTCOME MEASURES

Per capita number of clinically active physicians by specialty adjusted for age and sex population differences and out-of-region health care utilization. The measured physician workforce was compared with 4 benchmarks: the staffing within a large (2.4 million members) health maintenance organization (HMO), a hospital referral region dominated by managed care (Minneapolis, Minn), a hospital referral region dominated by fee-for-service (Wichita, Kan), and the proposed "balanced" physician supply (50% generalists).

RESULTS

The proportion of the US population residing in hospital referral regions with a higher per capita generalist workforce than the benchmark was 96% for the HMO benchmark, 60% for Wichita, and 27% for Minneapolis. The specialist workforce exceeded all 3 benchmarks for 74% of the population. The per capita workforce of generalists was not related to the proportion of generalists among regions (Pearson correlation coefficient=0.06; P=.26).

CONCLUSIONS

Population-based benchmarking offers practical advantages to needs- or demand-based planning for estimating a reasonably sized per capita workforce of clinically active physicians. The physician workforce within the benchmarks of an HMO and health care markets indicates the varying opportunities for regional physician employment and services. The ratio of generalists to specialists does not measure the adequacy of the supply of the generalist workforce either nationally or for specific regions. Research measuring the relationship between physician workforces of different sizes and population outcomes will guide the selection of future regional benchmarks.

Hospital readmission rates for cohorts of Medicare beneficiaries in Boston and New Haven

BACKGROUND

Geographic variations in the use of hospital services are associated with differences in the availability of hospital beds. There continues to be uncertainty about the extent to which unmeasured case-mix differences explain these findings. Previous research showed that the number of occupied beds per capita in Boston was substantially higher than the number of occupied beds per capita in New Haven, Connecticut, and that overall rates of hospital utilization were higher for Boston residents than for New Haven residents.

METHODS

We used Medicare claims data to study cohorts of Medicare beneficiaries 65 years of age or older and residing in Boston or New Haven who were initially hospitalized for one of five indications (acute myocardial infarction, stroke, gastrointestinal bleeding, hip fracture, or potentially curative surgery for breast, colon, or lung cancer). Residents of Boston or New Haven who were discharged between October 1, 1987, and September 30, 1989, were enrolled in the cohort corresponding to the earliest such admission and followed for up to 35 months.

RESULTS

The relative rate of readmission in Boston as compared with New Haven was 1.64 (95 percent confidence interval, 1.53 to 1.76) for all cohorts combined, with a similarly elevated rate for each of the five clinical cohorts and each age, sex, and race subgroup examined. Hospital-specific readmission rates varied substantially among the hospitals in Boston and were higher than those in New Haven. No relation was found between mortality (during the first 30 days after discharge or over the entire study period) and either community or hospital-specific readmission rates.

CONCLUSIONS

Regardless of the initial cause of the admission, Medicare beneficiaries who were initially hospitalized in Boston had consistently higher rates of readmission than did Medicare beneficiaries hospitalized in New Haven. Differences in the severity of illness are unlikely to explain these findings. One possible explanation is a threshold effect of hospital-bed availability on decisions to admit patients.

Standardized rates of recurrent outcomes

Longitudinal studies are often concerned with estimating the rate of an event that may recur. Examples are nonmelanoma skin cancer rates, screening rates for breast cancer using mammography and hospital admission rates. We propose simple estimators for directly and indirectly standardized summary rates and relative rates of recurrent events and their variances. We also develop an estimator of the excess rate in an area if the rate in another area applied. For non-recurrent events, the estimators are identical to the usual standardized summary rates. The estimators are independent of the underlying distribution of the event of interest and allow for unequal follow-up times and event rate heterogeneity among individuals. The method is not computationally intensive and does not require specialized software. We illustrate the application of the method in a retrospective cohort study of hospital utilization patterns of Medicare enrollees in Boston and New Haven over a three and a half year period.

Using administrative data to describe casemix: a comparison with the medical record

We compared the coding of comorbid conditions in an administrative database to that found in medical records for 485 men who had undergone a prostatectomy. Only a few specific conditions showed good agreement between charts and claims. Most showed poor agreement and appeared more frequently in the chart. A comorbidity index calculated from each of these sources was used to explore the differences in mortality for patients who had undergone transurethral vs open prostatectomy. The claims-based comorbidity index most often underestimated the index from the chart. Proportional hazards analysis showed that models including either comorbidity index were better than those without an index and models with information from both indices were best. No analysis eliminated the effect of type of prostatectomy on long-term mortality. Claims-based measures of comorbidity tend to underrepresent some conditions but may be an acceptable first step in controlling for differences across patient populations.

Internal validation of Medicare claims data

The Medicare database is commonly used for epidemiology and health services research, but validation of its data by chart review or questionnaire may be difficult and expensive. Since hospital and physician bills are independent in Medicare, however, these two data sources can be used to supplement and corroborate each other. This "internal validation" is illustrated here for hip fracture and prostatectomy. Agreement of the hospital and physician data streams regarding site of hip fracture (neck vs other), treatment of hip fracture (internal fixation vs arthroplasty), and type of prostatectomy (transurethral resection of prostate, open, or radical) was excellent, with percentage of agreement generally between 89% and 99%, and kappa statistics typically between 0.74 and 0.95. When validation with outside data sources is not readily available, such internal validation of Medicare data may be valuable.

Treatment and survival among elderly Americans with hip fractures: a population-based study

OBJECTIVES

This study was undertaken to examine the patterns of treatment and survival among elderly Americans with hip fracture.

METHODS

A 5% national sample of Medicare claims was used to identify patients who sustained hip fractures between 1986 and 1989. In comparing treatment patterns across regions, direct standardization was used to derive age- and race-adjusted percentages. Logistic regression and Cox regression were used to examine short- and long-term survival.

RESULTS

In the United States, 64% of femoral neck fractures were treated with arthroplasty; 90% of pertrochanteric fractures were treated with internal fixation. Higher short- and long-term mortality was associated with being male, being older, residing in a nursing home prior to fracture, having a higher comorbidity score, and having a pertrochanteric fracture. Blacks and Whites had similar 90-day postfracture mortality, but Blacks had a higher mortality later on. For femoral neck fracture, internal fixation has a modestly lower short-term mortality associated with it than arthroplasty has.

CONCLUSION

Variation in the treatment of hip fracture was modest, The increased delayed mortality after hip fracture among Blacks requires further study.

Identifying complications of care using administrative data

The Complications Screening Program (CSP) is a method using standard hospital discharge abstract data to identify 27 potentially preventable in-hospital complications, such as post-operative pneumonia, hemorrhage, medication incidents, and wound infection. The CSP was applied to over 1.9 million adult medical/surgical cases using 1988 California discharge abstract data. Cases with complications were significantly older and more likely to die, and they had much higher average total charges and lengths of stay than other cases (P < 0.0001). For most case types, 13 chronic conditions, defined using diagnosis codes, increased the relative risks of having a complication after adjusting for patient age. Cases at larger hospitals and teaching facilities generally had higher complication rates. Logistic regression models to predict complications using demographic, administrative, clinical, and hospital characteristics variables, had modest power (C statistics = 0.64 to 0.70). The CSP requires further evaluation before using it for purposes other than research.

Why are children hospitalized? The role of non-clinical factors in pediatric hospitalizations

OBJECTIVE

Pediatric medical discharge rates vary widely across hospital service areas, beyond differences explained by chance or disease incidence alone. This study examines the relationship between the characteristics of local medical services and the likelihood of hospitalization.

DESIGN

Small area and population-based regression analysis.

SETTING

The 72 hospital service areas of Maine, New Hampshire, and Vermont.

STUDY POPULATION

The 589,290 (1989) children of Maine, New Hampshire, and Vermont < 15 years of age with 120,806 discharges during 1985 through 1989.

MEASUREMENT AND MAIN RESULTS

Using logistic regression and controlling for community income, we found that children residing in zip codes with high per capita bed supply (4.0/1000) had 9% more discharges (odds ratio: 1.09; 99% confidence interval: 1.07, 1.11) compared with children in areas with low per capita bed supply (1.9/1000). Children living 30 minutes from the nearest hospital had 15% fewer medical discharges (odds ratio: 0.849; confidence interval: 0.830, 0.867) than those living in a zip code with a hospital. Residence in one of the three academic medical center hospital service areas resulted in 32% fewer discharges (odds ratio: 0.68; confidence interval: 0.66, 0.70). Similar and statistically significant (P < .01) results were noted for the most common nonperinatal diagnostic categories: asthma/bronchitis (diagnostic related group = 98) and gastroenteritis (diagnostic related group = 184). No effect was noted for femur fracture, a condition for which admission rates equal disease incidence.

CONCLUSIONS

The supply and character of medical care are important influences on the likelihood of hospitalization for pediatric medical conditions for which outpatient alternatives are available.

Academic health centers and health care reform

There is increasing support for the proposition that academic health centers have a duty to accept broad responsibility for the health of their communities. The Health of the Public program has proposed that centers become directly involved in the social-political process as advocates for reform of the health care system. Such engagement raises important issues about the roles and responsibilities of centers and their faculties. To address these issues, the authors draw upon the available literature and their experiences in recent health care reform efforts in Minnesota and Vermont in which academic health center faculty participated. The authors discuss (1) the problematic balance between academic objectivity and social advocacy that faculty must attempt when they engage in the health care reform process; (2) the management of the sometimes divergent interests of academic health centers, some of their faculty, and society (including giving faculty permission to engage in reform efforts and developing a tacit understanding that distinguishes faculty positions on reform issues from the center's position on such issues); and (3) the challenge for centers to develop infrastructure support for health reform activities. The authors maintain that academic health centers' participation in the process of health care reform helps them fulfill the trust of the public that they are obligated to and ultimately depend on.

Estimating the variance of standardized rates of recurrent events, with application to hospitalizations among the elderly in New England

Usual approaches for estimating the variance of a standardized rate may not be applicable to rates of recurrent events. Where individuals are prone to repeated health events, Greenwood and Yule (J R Stat Soc [A], 1920;83:255-79) advocated use of the negative binomial distribution to account for departures from the assumption of randomness of recurrent events required by the Poisson distribution. In this paper, the authors implemented the negative binomial distribution in the computation of annual hospitalization rates within certain hospital market areas. Data used were from 1,549,915 New England residents aged 65 years or more who were enrolled in Medicare between October 1, 1988, and September 30, 1989, and who had 458,593 hospital admissions during that year. New England was partitioned into 170 hospital market areas ranging in population size from 162 to 70,821 elderly Medicare enrollees. The negative binomial distribution demonstrated substantially better fits than the Poisson distribution to the numbers of hospitalizations within hospital market areas. Estimated standard errors for indirectly standardized rates based on the negative binomial distribution were 25-51 percent higher than estimated standard errors that assumed an underlying Poisson distribution. Using regression analysis to smooth overdispersion parameters across hospital market areas produced similar results. The approach described in this paper may be useful in estimation of confidence intervals for standardized rates of recurrent events when these events do not recur randomly.