Cost of care for patients in cancer clinical trials

BACKGROUND

Information on the costs of medical care for patients enrolled in clinical trials is needed by policymakers evaluating ways to facilitate clinical research in a managed care environment. We examined the direct costs of medical care for patients enrolled in cancer clinical trials at a large health maintenance organization (HMO).

METHODS

Costs for 135 patients who entered 22 cancer clinical trials (including 12 breast cancer trials) at Kaiser Permanente in Northern California, from 1994 through 1996 were compared with costs for 135 matched control subjects who were not enrolled in such trials. Cancer registry data and medical charts were used in matching the control subjects to the trial enrollees with respect to cancer site, stage, date of diagnosis, age, sex, and trial eligibility. The direct costs of medical care were compared between trial enrollees and the control subjects for a 1-year period, with data on costs and utilization of services obtained from Kaiser Permanente databases and medical charts.

RESULTS

Mean 1-year costs for the enrollees in trials were 10% higher than those for the control subjects ($17 003 per enrollee compared with $15 516 per control subject; two-sided P =.011). The primary component of this difference was a $1376 difference in chemotherapy costs ($4815 per trial enrollee versus $3439 per control subject; two-sided P<.001). Costs for the 11 enrollees in trials that had a bone marrow transplant (BMT) arm were approximately double the costs for their matched control subjects (borderline significance: two-sided P=.054). The $15 041 mean cost for the enrollees in trials without BMT was similar to the $15 186 mean cost for their matched control subjects.

CONCLUSIONS

Participation in cancer clinical trials at a large HMO did not result in substantial increases in the direct costs of medical care.

Survival and treatment for colorectal cancer Medicare patients in two group/staff health maintenance organizations and the fee-for-service setting

The current study compares treatment use and long-term survival in colorectal cancer patients between Medicare beneficiaries enrolled in two large prepaid group/staff health maintenance organizations (HMOs) and the fee-for-service (FFS) setting. The study is based on 15,352 colorectal cancer cases diagnosed between 1985 and 1992 and followed through 1995. Survival differences between the HMO and FFS cases were assessed using Cox regression. Treatment differences were evaluated using logistic regression. HMO cases had a lower overall mortality than did FFS cases but not a significantly lower colorectal cancer-specific mortality. Use of surgical resection was similar between HMO and FFS cases. However, rectal cancer cases in the HMOs were more likely to receive postsurgical radiation therapy than FFS cases. Superior overall survival in the HMOs may be the result of increased colorectal cancer screening, greater use of adjuvant therapies, and selection of healthier individuals.

Prostate cancer treatment and ten-year survival among group/staff HMO and fee-for-service Medicare patients

OBJECTIVE

To compare treatment patterns and the ten-year survival of prostate cancer patients in two large, nonprofit, group/staff HMOs to those of patients receiving care in the fee-for-service health setting.

DATA SOURCES/STUDY DESIGN

A cohort of men age 65 and over diagnosed with prostate cancer between 1985 and the end of 1992 and followed through 1994. Subjects (n = 21,741) were ascertained by two population-based tumor registries covering the greater San Francisco-Oakland and Seattle-Puget Sound areas. Linkage of registry data with Medicare claims data and with HMO inpatient utilization data allowed the determination of health plan enrollment and the measurement of comorbid conditions. Multivariate regression models were used to examine HMO versus FFS treatment and survival differences adjusting for sociodemographic and clinical characteristics.

PRINCIPAL FINDINGS

Among cases with non-metastatic prostate cancer, HMO patients were more likely than FFS patients to receive aggressive therapy (either prostatectomy or radiation) in San Francisco-Oakland (odds ratio [OR] = 1.69, 95% CI = 1.46-1.96) but not in Seattle (OR = 1.15, 0.93-1.43). Among men receiving aggressive therapy, HMO cases were three to five times more likely to receive radiation therapy than prostatectomy. Overall mortality was equivalent over ten years (HMO versus FFS mortality risk ratio [RR] = 1.01, 0.94-1.08), but prostate cancer mortality was higher for HMO cases than for FFS cases (RR = 1.25, 1.13-1.39).

CONCLUSION

Despite marked treatment differences for clinically localized prostate cancer, overall ten-year survival for patients enrolled in two nonprofit group/staff HMOs was equivalent to survival among patients receiving care in the FFS setting, even after adjustment for sociodemographic and clinical characteristics. Similar overall but better prostate cancer-specific survival among FFS patients is most plausibly explained by differences between the HMO and FFS patients in both tumor characteristics and unmeasured patient selection factors.

A diagnostic aid for detecting (DSM-IV) mental disorders in primary care

This study was designed to develop and validate a new computerized version of the Symptom Driven Diagnostic System for Primary Care (SDDS-PC) and examine its feasibility in primary care practice. One thousand and one patients (ages 18-70) coming for routine care to Kaiser-Permanente were screened on a self-administered symptom scale for major depression, alcohol and drug dependence, generalized anxiety, panic and obsessive compulsive disorders, and suicidal behavior. The screen was followed up by a brief diagnostic interview, administered by a nurse, which yielded a one-page summary of positive symptoms and a provisional computer-generated diagnosis for the physician. The physician reviewed the summary results and made a diagnosis. The nurse and physician were blind to the screen results. Patients were reinterviewed within 96 hours by a mental health professional (MHP) blind to previous results. The nurses' interviews ranged between 1.5 and 3.5 minutes for a screened positive diagnosis. Agreement between the nurse and physician diagnoses was excellent to moderate. Disagreement was usually in the direction of the physician ruling out major mental disorders in favor of subsyndromal or medical explanations. Only rarely did physicians diagnose disorders not detected by the nurse interview. Agreement between physician and MHP was moderate. Physicians using the SDDS-PC seldom made diagnoses that were not confirmed by the independent assessment of the MHP. The SDDS-PC may facilitate recognition of psychiatric disorders and minimize the physician's time in information gathering.

Projected cost-effectiveness of primary angioplasty for acute myocardial infarction

OBJECTIVES

This study sought to evaluate the cost-effectiveness of primary angioplasty for acute myocardial infarction under varying assumptions about effectiveness, existing facilities and staffing and volume of services.

BACKGROUND

Primary angioplasty for acute myocardial infarction has reduced mortality in some studies, but its actual effectiveness may vary, and most U.S. hospitals do not have cardiac catheterization laboratories. Projections of cost-effectiveness in various settings are needed for decisions about adoption.

METHODS

We created a decision analytic model to compare three policies: primary angioplasty, intravenous thrombolysis and no intervention. Probabilities of health outcomes were taken from randomized trials (base case efficacy assumptions) and community-based studies (effectiveness assumptions). The base case analysis assumed that a hospital with an existing laboratory with night/weekend staffing coverage admitted 200 patients with a myocardial infarction annually. In alternative scenarios, a new laboratory was built, and its capacity for elective procedures was either 1) needed or 2) redundant with existing laboratories.

RESULTS

Under base case efficacy assumptions, primary angioplasty resulted in cost savings compared with thrombolysis and had a cost of $12,000/quality-adjusted life-year (QALY) saved compared with no intervention. In sensitivity analyses, when there was an existing cardiac catheterization laboratory at a hospital with > or = 200 patients with a myocardial infarction annually, primary angioplasty had a cost of < $30,000/QALY saved under a wide range of assumptions. However, the cost/QALY saved increased sharply under effectiveness assumptions when the hospital had < 150 patients with a myocardial infarction annually or when a redundant laboratory was built.

CONCLUSIONS

At hospitals with an existing cardiac catheterization laboratory, primary angioplasty for acute myocardial infarction would be cost-effective relative to other medical interventions under a wide range of assumptions. The procedure's relative cost-ineffectiveness at low volumes or redundant laboratories supports regionalization of cardiac services in urban areas. However, approaches to overcoming competitive barriers and close monitoring of outcomes and costs will be needed.

Breast cancer survival and treatment in health maintenance organization and fee-for-service settings

BACKGROUND

Enrollment in health maintenance organizations (HMOs) has increased rapidly during the past 10 years, reflecting a growing emphasis on health care cost containment. To determine whether there is a difference in the treatment and outcome for female patients with breast cancer enrolled in HMOs versus a fee-for-service setting, we compared the 10-year survival and initial treatment of patients with breast cancer enrolled in both types of plans.

METHODS

With the use of tumor registries covering the greater San Francisco-Oakland and Seattle-Puget Sound areas, respectively, we obtained information on the treatment and outcome for 13,358 female patients with breast cancer, aged 65 years and older, diagnosed between 1985 and 1992. We linked registry information with Medicare data and data from the two large HMOs included in the study. We compared the survival and treatment differences between HMO and fee-for-service care after adjusting for tumor stage, comorbidity, and sociodemographic characteristics.

RESULTS

In San Francisco-Oakland, the 10-year adjusted risk ratio for breast cancer deaths among HMO patients compared with fee-for-service patients was 0.71 (95% confidence interval [CI] = 0.59-0.87) and was comparable for all deaths. In Seattle-Puget Sound, the risk ratio for breast cancer deaths was 1.01 (95% CI = 0.77-1.33) but somewhat lower for all deaths. Women enrolled in HMOs were more likely to receive breast-conserving surgery than women in fee-for-service (odds ratio = 1.55 in San Francisco-Oakland; 3.39 in Seattle). HMO enrollees undergoing breast-conserving surgery were also more likely to receive adjuvant radiotherapy (San Francisco-Oakland odds ratio = 2.49; Seattle odds ratio = 4.62).

CONCLUSIONS

Long-term survival outcomes in the two prepaid group practice HMOs in this study were at least equal to, and possibly better than, outcomes in the fee-for-service system. In addition, the use of recommended therapy for early stage breast cancer was more frequent in the two HMOs.

The impact of aging and chronic disease on use of hospital and outpatient services in a large HMO: 1971-1991

OBJECTIVES

To examine overall and diagnosis-specific trends in the use of inpatient and outpatient medical services (1970-1988) among older members of a large HMO.

DESIGN

Two cohorts of approximately 3000 persons aged 65 or older in 1971 and 1980 were compared for hospital and outpatient utilization during 9-year follow-up periods (1971-79 and 1980-88). All subjects were evaluated for vital status throughout the follow-up period as well.

PARTICIPANTS

All 6057 subjects were members of the Northern California Kaiser Permanente Medical Care Program in 1971 or 1980. The study sample was sex-age stratified (65-69,70-79,80+) at baseline.

MEASUREMENTS

Data on demographics, outpatient health services utilization, categories of outpatient utilization and disease diagnoses were obtained from membership lists or medical chart review; inpatient utilization, including admitting and discharge diagnosis, length of stay, and number of hospital days was assessed from computerized hospitalization records.

RESULTS

Hospital discharge rates (sex-age adjusted) increased by 12% between cohorts, with the largest increases at the oldest ages. There was a 25% increase among women and a 9% increase among men. Length of stay decreased by 20%. Hospitalization for ischemic heart disease decreased by 17%. Congestive heart failure (CHF) discharge rates (sex-age adjusted) were 92% higher in the 1980-88 cohort. For diagnoses related to nursing home institutionalization and frailty, discharge rates were significantly higher in the 1980-88 cohort: pneumonia (+34%), urinary tract infections (+104%), dehydration (+110%), osteoarthritis (+64%), syncope (+246%), leg cellulitis (+70%). In-hospital survival improved, but overall percent of readmissions also increased by 4%; readmissions for CHF increased by 13% and those for conditions of frailty by 120%. Overall outpatient visits increased by 17%. Use of laboratory tests (+57%) and outpatient surgeries (+99%) increased for all age strata in 1980-88 compared with 1971-79.

CONCLUSIONS

While overall outpatient and inpatient utilization has largely decreased over the past 30 years, as a result of economic factors and improved treatments for some major diseases, there has been an increase in utilization among older people. Hospitalization for diagnoses associated with end-stage cardiovascular disease (CHF), musculoskeletal disease, frailty and iatrogenic aspects of institutionalization are clearly increasing substantially. The largest impact of aging on health care may be the result of institutionalization and its sequelae. Improved treatment for cardiovascular disease may also be leading to increased utilization at later stages in the disease process.

Cost of care for cancer in a health maintenance organization

The direct costs of medical care for cancer are examined at Kaiser Permanente (KP) in Northern California. Use data from July 1987 through June 1991 were obtained from KP automated files for all 21,977 KP patients in the Bay Area SEER registry with cancer at one of seven cancer sites. Medical charts were reviewed for a stratified sample of 886 patients. Costs were estimated for initial, continuing, and terminal care, and for all person time within 15 years of diagnosis, by stage at diagnosis. From diagnosis until death or 15 years, long-term costs attributable to cancer were as follows: breast, $35,000; colon, $42,000; rectum, $51,000; lung, $33,000; ovarian, $64,000; prostate, $29,000; and Non-Hodgkin's Lymphoma (NHL), $48,000. The utilization and cost results reported here may be useful in assessing the cost-effectiveness of cancer prevention and control programs, in adjusting capitation rates and budgets, and in estimating the aggregate medical care costs attributable to cancer.

Variation among hospitals in coronary-angiography practices and outcomes after myocardial infarction in a large health maintenance organization

BACKGROUND

Wide geographic variation in the use of coronary angiography after myocardial infarction has been documented internationally and within the United States. An associated variation in clinical outcomes has not been consistently demonstrated.

METHODS

We assessed the risk of death from heart disease and of any heart disease event (death, reinfarction, or rehospitalization) over a follow-up period of one to four years in 6851 patients hospitalized with acute myocardial infarction at 16 Kaiser Permanente hospitals from 1990 through 1992. The percentage of patients who underwent angiography within three months after infarction ranged from 30 to 77 percent. We selected a subcohort of 1109 patients from three hospitals with higher rates of angiography and four with lower rates for a record review to assess the severity of infarction, the number of coexisting conditions, treatments received, and the appropriateness and necessity of angiography, using established criteria.

RESULTS

The rates of angiography were inversely related to the risk of death from heart disease (P= 0.03) and the risk of heart disease events (P<0.001) among the 16 hospitals after adjustment for age, sex, race, coexisting conditions, and the location of the infarction (subendocardial vs. transmural). In the subcohort, 440 patients met criteria indicating that angiography was necessary and 669 did not. Among the former, patients treated at hospitals with higher rates of angiography had a lower risk of death and of any heart disease event than those treated at hospitals with lower rates (hazard ratios, 0.67 and 0.72, respectively). Among the latter, the apparent benefits of being treated at hospitals with higher angiography rates were smaller (hazard ratios, 0.85 to 0.90 for death and any heart disease event, respectively).

CONCLUSIONS

During the one to four years after myocardial infarction, patients treated at hospitals with higher rates of angiography had more favorable outcomes than those treated at hospitals with lower rates. This association was stronger among patients for whom published criteria indicated that angiography was necessary.

Initial cost of primary angioplasty for acute myocardial infarction

OBJECTIVES

We sought to evaluate the initial economic cost of primary angioplasty for acute myocardial infarction under varying assumptions about whether a cardiac catheterization laboratory exists, whether services are provided during night and weekend hours and how cardiovascular surgical backup is arranged.

BACKGROUND

Primary angioplasty for acute myocardial infarction has resulted in clinical outcomes superior or equal to those obtained with thrombolysis in recent studies, but its future implementation depends greatly on its cost and cost-effectiveness. There is a gap in knowledge about the true economic costs of this procedure, and understanding costs under a variety of hypothetic scenarios is important in planning whether and how the procedure should be offered to broad groups of patients.

METHODS

A generalizable spreadsheet model was constructed to calculate the cost of primary angioplasty at a single hospital with assumptions based on data from a large nonprofit health maintenance organization (Kaiser Permanente). The following baseline assumptions were made: 1) A total of 200 patients with myocardial infarction presented to the hospital each year; 2) primary angioplasty was offered for 10 years; 3) the hospital had a cardiac catheterization laboratory; 4) costs of night call for technical personnel and cardiovascular surgical backup were already covered. Other scenarios were modeled to represent different assumptions about existing resources.

RESULTS

Under the baseline assumptions, primary angioplasty cost $1,597/procedure. If night call for technical personnel were a new expense, the average cost would be > or = $3,206. If a new cardiac catheterization laboratory needed to be built, costs would range from $3,866 to $14,339/procedure, depending on how cardiovascular surgical backup was provided. Results were sensitive to assumptions about the annual volume of myocardial infarctions, the number of years the procedure was offered and the costs of labor, construction and equipment.

CONCLUSIONS

The initial cost of providing primary angioplasty for acute myocardial infarction varies greatly, depending on the setting in which it is provided. To provide information for clinical policy decisions, a cost-effectiveness model is needed that combines these initial costs with data on survival, quality of life and rates and costs of subsequent cardiac procedures.

Trends in cardiovascular disease incidence and survival in the elderly

This study compared the age-specific incidence, postdiagnostic survival, and mortality for cardiovascular disease (CVD) in two cohorts of people aged 65 years and older. All subjects were members of a large prepaid health maintenance organization. The influence of changes in CVD risk factors on these rates also was evaluated. Trends in prevalence, incidence, postdiagnostic survival, and mortality for CVD were examined in both cohorts in 1971 and 1980. Myocardial infarction (MI), angina pectoris, stroke, and congestive heart failure (CHF) were included as CVD outcomes in this analysis. Nine-year prospective data on these diagnoses were abstracted from medical records and computerized hospitalization records for both cohorts. Age-sex-adjusted cardiovascular mortality was lower for both sexes by approximately 20% in the 1980 cohort. Overall survival did not change, whereas cancer mortality increased by 76% in women and 36% in men. With the exception of stroke, there was no increase in age-adjusted or age-specific prevalence. In men, the age-adjusted prevalence of stroke in men was 24% higher in the 1980 cohort. Age-adjusted 9-year incidence of MI, angina pectoris, stroke, and CHF did not change between cohorts in either sex Postdiagnostic, age-adjusted mortality for men with incident stroke was 24% lower in the 1980 cohort, and Postdiagnostic, age-adjusted mortality for men with incident angina was 35% lower in the 1980 cohort. Adjustment for risk factors measured at or before baseline had little influence on cohort differences in CVD incidence or duration of survival after CVD diagnosis. This study confirms other research showing a decline in CVD mortality over the past 20 years. These findings suggest that prevalent angina pectoris is increasing in men, and that survival with stroke and with angina is improving in men. Later diagnosis of incident CHF in men suggests that prevention and early detection may be postponing the development of more serious disease.

Brief screens for mental disorders in primary care

We evaluated a set of diagnostic screens for mental disorders in primary care. A self-administered screening questionnaire containing 26 items testing for multiple mental disorders was completed by 1,001 patients. Brief diagnostic modules, structured for psychiatric diagnoses, were subsequently administered to each patient by a research nurse. Operating characteristics of the screens were as follows: alcohol dependence (sensitivity [SE] 0.75; positive predictive value [PPV] 0.58; [kappa] 0.63), drug dependence (SE 0.50; PPV 0.50; kappa 0.50), generalized anxiety disorder (SE 0.74; PPV 0.44; kappa 0.44), major depressive disorder (SE 0.71; PPV 0.52; kappa 0.50), obsessive compulsive disorder (SE 0.71; PPV 0.15; kappa 0.21), and panic disorder (SE 0.71; PPV 0.43; kappa 0.48). Other chance-corrected measures of agreement are also reported, and criterion validity of the screens is examined. The results provide evidence that the screens discriminate between patients with symptomatology meeting established diagnostic criteria and those without. They detected previously unrecognized cases in this study and may prove to be valuable tools for psychiatric diagnosis in primary care.

Prevalence and incidence of adult pertussis in an urban population

OBJECTIVES

To determine the prevalence of Bordetella pertussis infection among adults who have prolonged cough for 2 weeks or longer and to estimate the incidence of B pertussis infection in adults in a defined urban population.

DESIGN

A prospective clinical study.

SETTING

Kaiser Permanente, San Francisco (Calif) Medical Center.

PARTICIPANTS

One hundred fifty-three referred and participating health plan members 18 years old or older with the complaint of cough persisting for 2 weeks or longer and 154 health plan members 18 years old or older with no cough for the past 3 months (controls) were enrolled. Medical records for an additional 100 patients randomly sampled from 676 patients 18 years old or older with an ambulatory diagnosis of cough (60 with prolonged cough) were also reviewed.

MAIN OUTCOME MEASURES

Prevalence of adult pertussis as determined by enzyme-linked immunosorbent assay IgG antibody levels to pertussis toxin in individuals with prolonged cough for 2 weeks or longer and the incidence of adult pertussis in San Francisco Kaiser health plan members.

RESULTS

The prevalence of adult pertussis was 12.4% of the participating referrals. The incidence of adult pertussis was estimated to be 176 cases per 100 000 person-years (95% confidence interval, 97 to 255 cases).

CONCLUSIONS

Adult pertussis is a significantly greater public health threat than previously suspected. Booster doses of acellular pertussis vaccine after 7 years of age may be an effective approach to minimize transmission and infection.

Effect of a copayment on use of the emergency department in a health maintenance organization

BACKGROUND

Use of the emergency department for nonemergency care is frequent and costly. We studied the effect of a copayment on emergency department use in a group-model health maintenance organization (HMO).

METHODS

We examined the use of the emergency department in 1992 and 1993 by 30,276 subjects who ranged in age from 1 to 63 years at the start of the study and belonged to the Kaiser Permanente HMO in northern California. We assessed their use of various HMO services and their clinical outcomes before and after the introduction of a copayment of $25 to $35 for using the emergency department. This copayment group was compared with two randomly selected control groups not affected by the copayment. One control group, with 60,408 members, was matched for age, sex, and area of residence to the copayment group. The second, with 37,539 members, was matched for these factors and also for the type of employer.

RESULTS

After adjustment for age, sex, socioeconomic status, and use of the emergency department in 1992, the decline in the number of visits in 1993 was 14.6 percentage points greater in the copayment group than in either control group (P<0.001 for each comparison). Visits for urgent care did not increase among subjects in any stratum defined by age and sex, and neither did the number of outpatient visits by adults and children. The decline in emergency visits for presenting conditions classified as "always an emergency" was small and not significant. For conditions classified as "often an emergency". "sometimes not an emergency", or "often not an emergency", the declines in the use of the emergency department were larger and statistically significant, and they increased with decreasing severity of the presenting condition. Although our ability to detect any adverse effects of the copayment was limited, there was no suggestion of excess adverse events in the copayment group, such as increases in mortality or in the number of potentially avoidable hospitalizations.

CONCLUSIONS

Among members of an HMO, the introduction of a small copayment for the use of the emergency department was associated with a decline of about 15 percent in the use of that department, mostly among patients with conditions considered likely not to present an emergency.

Alcohol use and medical care utilization among health maintenance organization patients in the emergency department

OBJECTIVE

To determine the association of an alcohol-related ED visit with medical care utilization during a two-year period surrounding the ED visit in an HMO.

METHODS

A probability sample of ED patients were interviewed and underwent breath analysis in a large HMO in a Northern California county. Based on recent alcohol intake or documentation of an alcohol-related ED visit, the patients were assigned to an alcohol group (n = 91) or a non-alcohol group (n = 897). A 10% random sample of the health plan membership of the same county (n = 19,968) served as a comparison group. Utilization data were obtained from computerized files. Multiple linear regression was used to determine differences in subsequent outpatient visit rates between the alcohol and the non-alcohol groups. Logistic regression was used to compare the risks of hospitalization in the two groups.

RESULTS

Annual outpatient visit rates were 7.8 in the alcohol group and 8.3 in the non-alcohol group (p = 0.65), controlling for gender, age, and injury status, and were significantly different from the visit rate of 5.5 for the random health plan sample (p = 0.0001). No difference was found between the alcohol and the non-alcohol groups for risk of hospitalization; however, those in the health plan sample were less than half as likely to be hospitalized as were those in the non-alcohol group (odds ratio 0.44, p = 0.002).

CONCLUSIONS

No difference was found in utilization of medical services between the alcohol and the non-alcohol groups in this predominantly white, well-educated HMO ED population. However, both groups used significantly more inpatient and outpatient services than did the general HMO membership.

The increased risk of coronary heart disease associated with nephrotic syndrome

Patients with nephrotic syndrome (NS) are believed to be at increased risk of atherosclerosis and coronary heart disease (CHD), although existing evidence for this association has not been persuasive. The risk of CHD among 142 persons with NS documented by protein-uria > or = 3.5 g daily was compared with that among 142 matched controls randomly selected from the membership of a large Northern California health plan. Controls were matched for sex, year of birth, and presence in the health plan when the referent case was diagnosed. No diabetics were included in this study. Mean follow-up for nonfatal CHD events was 5.6 years for NS subjects and 11.2 years for controls. Among the NS subjects myocardial infarction (MI) developed in 11, and there were 58 deaths, seven because of CHD. Among the controls, there were four MIs and 10 deaths, three because of CHD. In matched-pair analysis, there were 11 MIs among NS subjects and none among controls [P = 0.001, lower bound of 95% confidence interval for relative risk (CI), 2.8]. In an unmatched analysis adjusted for hypertension and smoking at diagnosis of NS, the relative risk of MI was 5.5 (95% CI 1.6 to 18.3) and the relative risk of coronary death was 2.8 (95% CI 0.7 to 11.3). Omitting data of NS subjects with minimal change disease and systemic lupus erythematosus yielded similar results. These data suggest that persons with NS are at increased risk of CHD.

Home blood pressure monitoring. Effect on use of medical services and medical care costs

The objective of this study was to determine whether a hypertension management program in which patients monitor their own blood pressure (BP) at home can reduce costs without compromising BP control. The prospective, randomized, controlled 1-year clinical trial was conducted at four medical centers of the Kaiser Permanente Medical Care Program in the San Francisco Bay Area. Of 467 patients with uncomplicated hypertension who were referred by their physicians, 37 declined to participate in the study; 215 were randomly assigned to a Usual Care (UC) group and 215 to a Home BP group. Twenty-five UC patients and 15 Home BP patients did not return for year-end BP measurements. Patients in the UC group were referred back to their physicians. Patients in the Home BP group were trained to measure their own BP and return the readings by mail. Patients were given a standard procedure to follow in case of unusually high or low BP readings at home. The number and type of outpatient medical services used were obtained from patient medical records for the study year and the prior year. Costs of care for hypertension were calculated by assigning relative value units to each outpatient service. Trained technicians measured each patient's BP at entry into the study and 1 year later. Home BP patients made 1.2 fewer hypertension-related office visits than UC patients during the study year (95% confidence interval (CI): 0.8, 1.7). Mean adjusted cost for physician visits, telephone calls, and laboratory tests associated with hypertension care was $88.76 per patient per year in the Home BP group, 29% less than in the UC group (95% CI: $16.11, $54.74). The annualized cost of implementing the home BP system was approximately $28 per patient during the study year and would currently be approximately $15. After 1 year, BP control in men in the Home BP group was better than in men in the UC group; BP control was equally good in women in both groups. Management of uncomplicated hypertension based on periodic home BP reports can achieve BP control with fewer physician visits, resulting in substantial cost savings.

The leukocyte count and cancer mortality

A previous report that the leukocyte count was related to mortality from cancer was evaluated in two large groups of multiphasic health examinees in the San Francisco Bay area, California--a cohort of about 25,000 persons followed up for mortality and a cohort of about 160,000 persons followed up for cancer incidence between 1964 and 1980. The leukocyte count was related to mortality from all cancers, smoking-related cancers, and cancers that were not smoking-related, but it was not related to cancer mortality in nonsmokers. The leukocyte count showed an association with the incidence of smoking-related cancers that was only partially removed by analytical control for smoking. It was only slightly, if at all, related to the incidence of not-smoking-related cancers and to the incidence of all cancers among nonsmokers. The relation of the leukocyte count to cancer mortality appears to be due to its close association with cigarette smoking, which raises the incidence of certain cancers and can hasten death attributed to cancer.

The fetal life table revisited: spontaneous abortion rates in three Kaiser Permanente cohorts

A cohort of 9,055 singleton pregnancies was identified by conventional urine tests or physician examination at the Kaiser Permanente Medical Care Program in Northern California in 1981-1982. Using life table methods, we estimated the cumulative risk of spontaneous abortion or fetal death through the end of pregnancy as 13.0% of all pregnancies surviving 1 week or more past the time of the first missed menses. This value was lower than the estimates of 15.1% and 16.0%, respectively, from two previous fetal life table studies conducted at Kaiser Permanente in prior decades, but similar to estimates from recent, smaller studies of early pregnancy diagnosed by human chorionic gonadotropin. The major difference in survival between the three Kaiser Permanente cohorts was in the earliest gestational week of observation, week 5 from the last menstrual period, where the older data were sparse and potentially biased. High loss rates during this week accounted for one-fourth to one-third of the cumulative risk observed in the older studies. Although the older cohorts were larger, the 1981-1982 cohort included five times and three times as many pregnancies under observation during week 5 from the last menstrual period, yielding more stable estimates for this period. Because of improved reliability of early pregnancy testing and an emphasis on early prenatal care, the mean gestational age at entry to the 1981-1982 cohort was 10.4 weeks from the last menstrual period compared to 14.3 weeks and 13.7 weeks for the older studies. All three studies showed a peak for risk of spontaneous abortion around weeks 10-12 from the last menstrual period.

Appendectomy, appendicitis, and large bowel cancer

A cohort of 167,561 persons who received multiphasic health checkups were followed up for cancer development. A history of appendectomy showed slightly negative nonsignificant associations with the development of cancer of the colon, rectum, and all sites combined. By inference, the relation of appendicitis with these cancers was also inverse. Upper 95% confidence limits were compatible only with small positive associations of appendectomy and appendicitis with these cancers. These data do not support the view that removing the appendix increases cancer risk by diminishing immunocompetency. A link between appendicitis and large bowel cancer has been noted in intersociety correlations and has been hypothesized to be due to prevention of both by a high-fiber diet. However, appendicitis does not appear to be a useful predictor of large bowel cancer within a developed society.

The cost of acquired immunodeficiency syndrome in northern California. The experience of a large prepaid health plan

We studied the cost of acquired immunodeficiency syndrome (AIDS) in the Kaiser Permanente Medical Care Program (KPMCP), northern California region. We report the costs of care to the KPMCP and introduce an innovative application of survival methods to cost analysis. From the beginning of the AIDS epidemic in 1981 to the end of June 1987, 866 cases of AIDS were recorded among members of the KPMCP. Estimates of the costs of care of these patients were derived from comprehensive chart reviews of a random sample of 71 patients whose conditions were diagnosed from January 1984 through June 1987. Total mean lifetime costs per patient were $32,816 (median, $28,677), whereas the mean hospital per diem cost was $20,446 per patient. As more care was shifted to outpatient services overtime, overall costs dropped, despite marked increases in the cost of outpatient medications such as zidovudine. The overall estimate of cost compared closely with other estimates of the cost of care in San Francisco, Calif, and it is lower than estimates from elsewhere in the United States, probably because of the low proportion of cases associated with intravenous drug use and the well-developed social support networks available to patients with AIDS in the San Francisco Bay Area.

Screening prescription drugs for possible carcinogenicity: eleven to fifteen years of follow-up

Using computerized pharmacy records from 1969 to 1973 for a cohort of 143,574 members of the Kaiser Permanente Medical Care Program, we have been testing associations of 215 drugs or drug groups with subsequent incidence of cancer at 56 sites. This paper presents findings with follow-up through 1984. There were 227 statistically significant (P less than 0.05, two-tailed) associations: 170 positive, 57 negative. Some were undoubtedly chance findings; others were likely due to confounding by unmeasured covariables. However, several associations suggested hypotheses for further studies and/or the need for continued observation. Most notable among findings not previously reported were associations of several antibiotics, both oral and topical, with lung cancer. These associations could not be explained by indications for drug use or by differences in smoking habits between users and nonusers, and suggest a possible link between the occurrence of bacterial infections and risk for cancer. In general, our results continue to suggest that most medications used during that period did not affect cancer incidence substantially. However, for less frequently prescribed medications, our power to detect moderate increases in cancer risk was quite low.

Testing for recovery of thyroid function after withdrawal of long-term suppression therapy

Many persons are given thyroid hormone for long periods without sufficient justification. We selected 45 patients whose chart reviews did not demonstrate a clear need for thyroid replacement. Thyroid hormone was withdrawn and blood samples taken for free thyroxine index and TSH levels at 2, 4, 6, and 8 weeks after thyroid withdrawal. At 8 weeks, 30 of the 45 were normal. A single TSH test 8 weeks after thyroid withdrawal appears to be the most efficient way to separate euthyroid from hypothyroid patients.

Serum uric acid unrelated to cancer incidence in humans

We examined the hypothesis that low levels of serum uric acid are associated with elevated cancer risk. A subpopulation (163,830 members) of a large health maintenance organization was followed for a mean of 9.8 years after a multiphasic health checkup at which serum uric acid level was measured. Total cancer incidence as well as site-specific incidence (for lung, colon, and prostate cancer in men and lung, colon, breast, uterine, and cervical cancer in women) was ascertained from hospital discharge records and the Surveillance, Epidemiology and End Results program in the San Francisco-Oakland Bay area. Age-adjusted cancer incidence was not elevated in the lower deciles of serum uric acid level. After adjusting for age, race, education, smoking, alcohol consumption, and body mass, using proportional hazards models, the risk of cancer was not elevated at lower levels of uric acid. Our results suggest that if increased risk of cancer is associated with low serum uric acid, this risk is associated with serum uric levels below those commonly seen in human populations.

Efficacy of Haemophilus influenzae type b capsular polysaccharide vaccine

The efficacy of the Haemophilus influenzae type b (Hib) polyribose phosphate vaccine was evaluated in a population of 120,000 children from 23 through 71 months of age in the Kaiser Permanente Medical Care Program (KPMCP) in Northern California over the 2-year period from June 1, 1985, through May 31, 1987. Approximately 37% of the population were vaccinated by the end of the first year and 60% were vaccinated by the end of the second year. There were 35 cases of Hib disease, 4 of whom were vaccine failures. Cases of Hib disease were identified by multiple modality case ascertainment, consisting of: (1) active surveillance in KPMCP microbiology laboratories; (2) active surveillance on KPMCP pediatric wards by a study physician; (3) retrospective review of computer-stored hospital discharge diagnoses; and (4) a review of all hospitalizations outside the health plan. The medical records of cases, matched controls and a random sample of the population were reviewed to obtain information on vaccination and related variables. Efficacy was evaluated using two complementary methods. In a retrospective surveillance approach, efficacy was estimated to be 68% (95% confidence limits of 4, 89%). In a matched case-control analysis, efficacy was estimated to be 69% (95% confidence limits of -13, 91%). Adjustment for day care attendance and parental occupation slightly reduced the efficacy estimate. Other possible confounders including race, parental education and number of siblings were considered. Four cases of Hib disease were observed within 1 week following receipt of vaccine and before the time when immunity could have developed. There are several plausible explanations for the occurrence of these early cases including the possibility of chance alone.(ABSTRACT TRUNCATED AT 250 WORDS)

Smoking, menopause, and breast cancer

As part of a multiphasic health examination, breast cancer incidence was studied in a cohort of 84,172 women who reported their smoking habits between 1964 and 1972. After adjustment for race, education, marital status, body mass, parity, age of menarche, and alcohol consumption, women currently smoking at examination had a slight increase in the relative risk of breast cancer; relative risk for light smokers was 0.95 (95% confidence interval--0.80, 1.11); for moderate smokers, 1.22 (1.05, 1.43); and for heavy smokers, 1.19 (0.88, 1.60) compared with non-smokers. Consistent with the hypothesis that estrogen levels mediate a small protective effect of smoking on the risk of breast cancer, we found that moderate and heavy smoking were associated with a 1.29-year and a 1.48-year reduction in the age of menopause. A 1-year reduction in age of menopause was associated with a 0.97 reduction in the risk of breast cancer. However, there was no indication that the overall effect of smoking on breast cancer was protective.

Serum retinol and retinol-binding protein levels do not predict subsequent lung cancer

Retinol and retinol-binding protein levels were measured in sera previously obtained, and stored in the frozen state, at multiphasic health checkups from 151 persons subsequently found to have lung cancer (cases) and 302 persons who remained free of cancer (controls). Two controls were matched to each case for sex, skin color, age, date of multiphasic health checkup, and aspects of the smoking habit. Mean levels in cases and controls were, respectively, retinol: 82.17 and 82.37 micrograms/dl (p = 0.93), and retinol-binding protein: 6.04 and 6.00 mg/dl (p = 0.81). Mean differences between cases and controls were, retinol: 0.195 micrograms/dl with 95% confidence limits, -3.91 and 4.30 micrograms/dl; retinol-binding protein: -0.033 mg/dl with 95% confidence limits, -0.31 and 0.24 mg/dl. No significant trend in relative risk of lung cancer was observed when the retinol or retinol-binding protein distribution was divided into quintiles. No significant associations were observed in subgroups based on age, sex, histologic type of cancer, cigarette consumption, or interval between blood drawing and cancer diagnosis. In this large study, retinol and retinol-binding protein levels were not useful in predicting the subsequent development of lung cancer.

Serum cholesterol and the incidence of cancer in a large cohort

The relation of serum cholesterol to the development of cancer remains unclear. We have examined the incidence of cancer in 160,135 men and women who were health plan members of the Northern California Kaiser Permanente Medical Care Program (KPMCP) and who had a multiphasic health examination in the period 1964 through 1972. In addition to all cancer, we examined individually the nine most common cancers in men and the 12 most common in women. Cancer diagnoses (N = 7477) recorded by the State of California Resource for Cancer Epidemiology Section and the health plan hospital discharge file were used to calculate incidence by quintile of serum cholesterol. Multivariate analysis adjusted for race, education, smoking status, alcohol consumption, body mass index and, in women, for age at menarche, parity, and menopausal status. No strong or consistent relation of low cholesterol to cancer incidence was found. Of the 21 cancers examined, only lymphoma in men and cervical cancer had significantly elevated risks at the lowest quintile of serum cholesterol compared with risks in the highest quintile. Cancer incidence in the first 2 years after the cholesterol measurement was consistently higher among persons whose cholesterol levels were in the lowest quintile. This prospective study did not find evidence that low cholesterol increased the risk of cancer but supports the idea that preclinical cancer in some way lowers serum cholesterol.

Multiphasic Health Checkup Evaluation: a 16-year follow-up

The Multiphasic Health Checkup Evaluation Study, a long-term clinical trial, has been completed. A study group of 5156 men and women age 35-54 at entry was urged to have annual multiphasic health checkups (MHCs) for 16 years. A control group of 5557 comparable subjects was not so urged but was followed up in a comparable fashion. The mean and median number of MHCs per person were 6.8 and 6, respectively, in the study group and 2.8 and 1, respectively, in the control group. During 16 years the study group experienced a 30% reduction (p less than 0.05) in deaths from pre-specified "potentially postponable" causes, largely associated with lower death rates from colorectal cancer and hypertension. This reduction was most pronounced in the early years of the study. The two groups did not differ to a statistically significant degree in mortality from all other causes (84% of total mortality) or in total mortality. There was no difference in self-reported disability in the overall groups. In the setting of our prepaid health care plan where MHCs were already available on a voluntary basis, a program of urging middle-aged persons to undergo regular MHCs brought about a substantial reduction in mortality from preselected diseases.

Stress management and mutual support groups in rheumatoid arthritis

Stress management and mutual support groups are employed widely in chronic illness, although their efficacy has not been established. To determine the effect of these measures on morbidity and psychologic health in rheumatoid arthritis, 105 patients meeting diagnostic criteria for rheumatoid arthritis were evaluated for depression, life satisfaction, functional disability, and indicators of disease activity. Patients were randomly assigned to one of three groups: (1) stress management; (2) mutual support; (3) no intervention (control). After completion of 10 weekly sessions, identical tests were performed for all patients in the intervention and control groups. Patients in the intervention groups showed greater improvement in joint tenderness than did the control patients but did not differ significantly from the patients in the control group in any of the other outcome measures.

Psychological questionnaire score, cigarette smoking, and myocardial infarction: a continuing enigma

The ability of a group of 94 psychological questions to discriminate between men in whom cigarette smoking was associated with increased risk of myocardial infarction and men in whom smoking was not so associated remains puzzling. Further analyses, controlling for reported alcohol consumption and for a questionnaire item that might reflect physical activity, failed to alter this finding. This interaction of the questionnaire responses with smoking was not found with two other major coronary risk factors, serum cholesterol and systolic blood pressure. Believing that these observations may provide (a) a clue to how cigarette smoking affects risk of myocardial infarction, or (b) some means of identifying greater or lesser susceptibility to the effects of smoking, we invite other investigators to join in the pursuit of this matter. A list of ten selected yes-or-no questions with strong interaction with smoking is provided to assist others in studying this phenomenon; these are similar to ten items on the Minnesota Multiphasic Personality Inventory.