Involuntary health plan switching: case study of a corporate health benefits program

This study examined the extent of health plan switching in one large corporation due to changes in employment, compared it with the extent of voluntary switching among continuously employed individuals, and evaluated the risk mix of health plan stayers, voluntary switchers, and involuntary switchers. Of 14,791 workers enrolled in the firm's fee-for-service plan in 1987, only 5,320 remained in 1990. Of the 11,494 employees enrolled in the large health maintenance organization (HMO) and the 7,677 enrolled in the small HMOs in 1987, only 5,299 and 3,026, respectively, remained in their HMOs and insured by the firm in 1990. These large enrollment losses were offset by large enrollment gains from new employees. Health plan leavers were at a lower risk of using medical services than were health plan stayers. The lowest expected annual expenditures were among newly hired health plan joiners.

Can postmenopausal hormone replacement improve plasma lipids in women with diabetes? The Atherosclerosis Risk in Communities Study Investigators

OBJECTIVE

to evaluate the association of postmenopausal hormone replacement with plasma lipids in diabetic women.

RESEARCH DESIGN AND METHODS

Cross-sectional data from a multiracial population study were used to evaluate the relationship of hormone replacement status with plasma lipids in diabetic (n = 694) versus nondiabetic (n = 5,321) postmenopausal women.

RESULTS

Although diabetic women who currently used hormone replacement had higher adjusted mean HDL cholesterol levels than those who did not (56.9 vs. 53.6 mg/dl), they had proportionately lower hormone-related increases in HDL, HDL2, and HDL3 cholesterol than did nondiabetic women (HDL cholesterol 64.9 [current users] vs. 55.7 mg/dl [those who never used hormones]). There was a trend toward greater triglyceride values with hormone replacement in diabetic women (156.6 [current users] vs. 125.4 mg/dl [those who never used hormones]) than in nondiabetic women (143.3 [current users] vs. 123.7 mg/dl [those who never used hormones]). LDL cholesterol and apolipoprotein B levels were lower and apolipoprotein A-I levels were higher with hormone replacement, to a similar degree in diabetic and nondiabetic women.

CONCLUSIONS

Diabetic women appear to have a blunted response to the HDL-raising effects of estrogen and an exaggerated hypertriglyceridemic response. This may result in attenuated cardioprotection from postmenopausal hormone replacement therapy and potentially an increased risk of acute pancreatitis from hypertriglyceridemia. The risks and benefits of postmenopausal hormone replacement need to be carefully weighed in diabetic women.

The dynamics and limits of corporate growth in health care

This paper analyzes the economic dynamics of five forms of organizational growth in health care: horizontal integration within a single geographic market; horizontal integration across different geographic markets; diversification among multiple products and types of service; diversification among multiple distribution channels; and vertical integration with suppliers. These principles are illustrated through brief case studies of three firms that have grown by way of internal expansion, mergers, acquisitions, and diversification: WellPoint Health Networks, UniHealth America, and Mullikin Medical Enterprises. The paper analyzes the potential limits of organizational growth in health care and explores the implications of integration and diversification for antitrust policy.

Vertical integration and organizational networks in health care

This paper documents the growing linkages between primary care-centered medical groups and specialists and between physicians and hospitals under managed care. We evaluate the two alternative forms of organizational coordination: "vertical integration," based on unified ownership, and "virtual integration," based on contractual networks. Excess capacity and the need for investment capital are major short-term determinants of these vertical versus virtual integration decisions in health care. In the longer term, the principal determinants are economies of scale, risk-bearing ability, transaction costs, and the capacity for innovation in methods of managing care.

The growth of medical groups paid through capitation in California

BACKGROUND

In California, it is common for health maintenance organizations (HMOs) to contract with large medical groups that are paid through capitation and are responsible for managing a full spectrum of medical services.

METHODS

We studied six large medical groups in California--Bristol Park Medical, Friendly Hills HealthCare Network, HealthCare Partners Medical Group, Mullikin Medical Centers, Palo Alto Medical Foundation, and San Jose Medical Group--that are paid through capitation and that are growing as a result of contracts with managed-care organizations. We conducted interviews and obtained data on factors such as patient enrollment, capitation and other revenue, numbers of days spent by enrollees in the hospital, and numbers of visits to physicians per enrollee.

RESULTS

Between 1990 and 1994, the number of HMO enrollees whose care was paid for through capitation in the six medical groups increased by 91 percent, from 398,359 to 759,474. In 1994, the mean number of hospital days per 1000 HMO enrollees ranged from 120 to 149 for non-Medicare patients and from 643 to 936 days for Medicare patients. By comparison, in 1993 the mean numbers of hospital days per 1000 HMO enrollees not covered by Medicare were 232 for California and 297 for the United States; for HMO enrollees covered by Medicare, the numbers were 1337 for California and 1698 for the United States. In 1994, the average annual number of visits to physicians for HMO patients in the six groups not covered by Medicare ranged from 3.1 to 3.9; for Medicare patients, it ranged from 7.2 to 9.3; these rates were slightly lower than statewide and national rates. Four of the groups have sold their assets (such as facilities, supplies, equipment, and patients' charts) to outside investors; the physicians remain employed by physician-owned professional corporations.

CONCLUSIONS

Medical groups paid through capitation offer a model for the status of physicians in managed-care systems that differs from the employee status offered by staff-model HMOs and the subcontractor status offered by HMOs that negotiate directly with individual physicians. Despite their growth, such medical groups in California face substantial challenges, such as obtaining the financial assets necessary to sustain rapid growth.

Adverse selection among multiple competing health maintenance organizations

This study examines risk selection among nine health plans competing for 16,182 employees of one large firm in 1989: one conventional fee-for-service plan, one group-model health maintenance organization (HMO), and seven network and independent practice model HMOs. We develop and compare measures of risk using weights based on HMO and fee-for-service expenditure data, respectively. We use a multiequation statistical model to develop two sets of utilization and expenditure weights for enrollees in each plan. One set of weights, based on discharge abstracts and outpatient records from the large group-model HMO, measures how much each of the nine groups of employees and dependents would have spent, had they been enrolled in a stringently managed plan with no consumer cost sharing. The other set of weights, based on fee-for-service claims data, measures how much each group would have spent, had it been enrolled in an unmanaged health plan with significant coinsurance and deductibles. Predicted annual expenditures per enrollee exhibit a 23% range from lowest (favorable selection) to highest (adverse selection) risk plans using the HMO weights and a 17% range using fee-for-service weights. The fee-for-service plan and group-model HMO with large enrollments have risk mixes near the center of the spectrum. Smaller HMOs exhibit the extreme forms of both favorable and adverse selection. The statistical methods adopted in this study can be used to risk-adjust capitation payments to competing health plans. As mergers among HMOs and group purchasing arrangements among employers increase the average enrollment in each plan from each payor, however, risk differences among plans will be attenuated and the need to risk-adjust payments will be less severe. Key words: health insurance; adverse selection; managed competition; health maintenance organization.

Chromosome 5 suppresses tumorigenicity of PC3 prostate cancer cells: correlation with re-expression of alpha-catenin and restoration of E-cadherin function

Considerable evidence now exists to support an important role for the E-cadherin-mediated cell-cell adhesion pathway as a suppressor of the invasive phenotype in adenocarcinoma cells. Previous studies have found that this pathway is frequently aberrant in prostate cancers, particularly those that are likely to metastasize. In this study, we report on the effects of re-establishment of this pathway in a prostate cancer cell line, PC-3, in which this adhesion system is dysfunctional by virtue of a deletion of the gene that codes for alpha-catenin, an E-cadherin-associated protein necessary for normal E-cadherin function. Re-expression of alpha-catenin was accomplished either by transfection of PC-3 cells with a copy of the alpha-catenin cDNA under the control of a heterologous promoter or by microcell-mediated transfer of chromosome 5, which contains the alpha-catenin gene and its normal regulatory elements. In both cases, re-expression of alpha-catenin is associated with a similar, dramatic alteration in cell morphology, whereby extensive cell-cell contact is observed. In the case of transfection of the cDNA, this expression is only transient, because the transfected cells either cease to proliferate or, more commonly, revert to the parental phenotype with concomitant cessation of alpha-catenin expression. In contrast, cells containing one or more copies of microcell-transferred chromosome 5 express alpha-catenin in a stable manner and continue to proliferate. Upon injection into nude mice, these latter cells are no longer tumorigenic, or form only slowly growing tumors with greatly extended doubling times when compared to the parental PC-3 cells. During passage in culture, clones that contain only one transferred copy of chromosome 5 reproducibly revert to the parental phenotype. This reversion is associated with loss of the chromosome 5 region containing the alpha-catenin gene and consequent loss of alpha-catenin expression, as well as re-emergence of tumorigenicity. Transfer of chromosome 5 into prostate cancer cells that are E-cadherin negative does not result in either morphological transformation or suppression of tumorigenicity, suggesting that these effects of alpha-catenin expression are dependent upon concomitant expression of E-cadherin. These data demonstrate the tumor suppressive ability of chromosome 5 in the PC-3 prostate cancer cells and suggest that re-expression of alpha-catenin with resultant restoration of E-cadherin function plays a critical role in this process.

Risk adjusting community rated health plan premiums: a survey of risk assessment literature and policy applications

This paper surveys recent health care reform debates and empirical evidence regarding the potential role for risk adjusters in addressing the problem of competitive risk segmentation under capitated financing. We discuss features of health plan markets affecting risk selection, methodological considerations in measuring it, and alternative approaches to financial correction for risk differentials. The appropriate approach to assessing risk differences between health plans depends upon the nature of market risk selection allowed under a given reform scenario. Because per capita costs depend on a health plan's population risk, efficiency, and quality of service, risk adjustment will most strongly promote efficiency in environments with commensurately strong incentives for quality care.

Superior cervical ganglionectomy in monkeys: aqueous humor dynamics and their responses to drugs

The role of sympathetic innervation in regulating the responses of aqueous humor flow, outflow facility and pupillary diameter to timolol and epinephrine was investigated in cynomolgus monkeys following unilateral superior cervical ganglionectomy. Aqueous humor flow was measured fluorophotometrically under pentobarbital anesthesia before the first and after the ninth of twice-daily topical doses of epinephrine, and under ketamine anesthesia before the first and after the ninth of twice-daily topical doses of timolol, 4-19 months after denervation. Baseline aqueous humor flow rates determined 2-4 months following denervation were 40% greater under ketamine than under pentobarbital anesthesia, with no difference between denervated and control eyes. Epinephrine increased aqueous humor flow by up to 50% in a dose-dependent fashion in both eyes, with a non-significant tendency toward slightly greater potency and efficacy in the denervated eyes. Timolol decreased aqueous humor flow by up to 50% in a dose-dependent fashion with equal maximal efficacy in both eyes, but with slightly and statistically significantly greater potency and efficacy in the control eyes at submaximal doses. Early (1-3 months) but not late (23-27 months) after denervation, baseline pupil diameter under ketamine anesthesia was smaller in the denervated eyes than in the controls. The mydriatic response to 600 micrograms epinephrine was more sensitive in the denervated than the control eye both early (1-3 months) and later on (23-27 months) after denervation; timolol had no effect on pupil diameter in either eye. No striking differences in intraocular pressure or refraction were observed between the eyes under any of these conditions. Resting outflow facility or resistance and perfusion-induced facility increase or resistance reduction, measured by two-level constant pressure perfusion under pentobarbital anesthesia 1.5-4.5 years after unilateral sympathectomy, did not differ significantly between sympathectomized and control eyes. Facility increased (by up to 30-50% beyond washout) and resistance decreased (by up to 20-30% beyond washout) similarly in control and sympathectomized eyes 10-60 min and 3-4 hr after bolus intracameral epinephrine doses of 0.55 and 5.5 micrograms.

Health care purchasing and market changes in California

This paper analyzes the process and outcomes of collective negotiations among large private employers and health maintenance organizations (HMOs) in California. In 1994, prior to collective negotiations, differences in benefit packages, risk mix, and volume of purchasing accounted for only one-third of the variance in premiums among firms and HMOs. The 1995 collective negotiations reduced the variance by 22 percent and the enrollment-weighted mean premium by approximately 9 percent, while enriching the standard benefit package. Savings for the eleven participating firms totaled $36.5 million. Large purchasers are reducing the number of health plans offered to their employees, standardizing the benefit package, using collective negotiations to contain costs, and shifting from vendor to partner relations with HMOs.

Phalloidin inhibits epinephrine's and cytochalasin B's facilitation of aqueous outflow

OBJECTIVE

To determine whether phalloidin, a fungal peptide that inhibits actin filament depolymerization, could inhibit the ability of cytochalasin B and epinephrine to increase the facility of aqueous outflow in the eyes of living cynomolgus monkeys.

METHODS

Outflow facility was determined by two-level constant-pressure perfusion of the anterior chamber. After measurement of baseline facility in both eyes, one eye of each animal received intracameral phalloidin (1.3, 13, or 130 mumol/L); the opposite eye received vehicle. Both eyes then received either epinephrine (0.3 mmol/L) or cytochalasin B (0.2 mmol/L), and facility was again measured.

RESULTS

Cytochalasin B and epinephrine increased facility by 120% to 190% and 100% to 180%, respectively (uncorrected for 15% resistance washout caused by perfusion itself). Phalloidin itself (13 or 130 mumol/L) did not affect facility, but it inhibited up to 50% of the facility-increasing effect of cytochalasin B and epinephrine.

CONCLUSIONS

We conclude that (1) the aqueous humor outflow facilitating effects of cytochalasin B or epinephrine depend in some manner on depolymerization of actin filaments within trabecular meshwork cells, and (2) actin filaments may help regulate aqueous outflow.

Apraclonidine and brimonidine effects on anterior ocular and cardiovascular physiology in normal and sympathectomized monkeys

Apraclonidine and brimonidine administered topically to one eye of ketamine-anesthetized normal cynomolgus monkeys each produced a dose-related bilateral reduction in intraocular pressure which was not dependent on intact sympathetic innervation. Brimonidine was more potent and efficacious (10-12 mmHg maximum intraocular pressure reduction 2 hr after 200 micrograms) but produced a shorter-lasting effect than apraclonidine (4 mmHg maximum intraocular pressure reduction 1-6 hr after 600-1000 micrograms). Apraclonidine had little effect on pupil diameter, but brimonidine produced a dose-related bilateral miosis which was dependent on intact sympathetic innervation. Neither drug significantly affected refractive error. Topical brimonidine, but not apraclonidine, produced a dose-dependent reduction in mean arterial blood pressure, while both drugs lowered heart rate. A dose-dependent bilateral reduction in aqueous humor flow rate calculated over a 6-hr period following drug administration was produced by both topical apraclonidine (maximum 30-35% reduction with 600 micrograms) and brimonidine (maximum 30-45% reduction with 50-250 micrograms), which was not dependent on intact sympathetic innervation. Maintenance of blood pressure by intravenous infusion of angiotensin II had no effect on the aqueous humor flow suppression produced by 100 micrograms of topical brimonidine, but pentobarbital anesthesia abolished it. Intracameral injection of 10 micrograms brimonidine in rhesus monkeys produced an ipsilateral approximately 15% reduction in aqueous humor flow calculated for the 1-3 hr post-injection period. The cardiovascular and contralateral ocular effects observed with both drugs are presumably related to the monkeys' small body weight, and the magnitude of IOP reduction for a given degree of flow suppression would be greater in hypertensive than in normotensive eyes. Caution must therefore be exercised in extrapolating from our data in ocular normotensive monkeys to the glaucomatous human.

Functional bowel disorders in women with dysmenorrhea

OBJECTIVES

The relationship between menstrual and bowel symptoms, the overlap between the diagnoses of dysmenorrhea (DYS) and functional bowel disorder (FBD), and markers that may be useful in discriminating functional bowel disorders from DYS were studied in 383 women (20-40 yr of age).

METHODS

All women completed the NEO Personality Inventory at intake and completed the Moos' Menstrual Distress Questionnaire and a bowel symptom inventory every 3 months for 12 months. Prostaglandin levels were measured in vaginal dialysate on the first day of menses.

RESULTS

DYS was diagnosed in 19.8% of the total sample. Functional bowel disorder, defined as abdominal pain with altered bowel function, was diagnosed in 61% of the DYS group compared with 20% of controls (p < 0.05). Neuroticism scores were significantly higher in subjects with functional bowel disorder with or without DYS. However, bowel symptoms were significantly correlated with menstrual symptoms even after statistically controlling for the effects of neuroticism. Painful menses and water retention distinguished the DYS group from the functional bowel disorder group. Prostaglandin levels were elevated in women with DYS, but did not consistently differentiate the diagnostic groups.

CONCLUSIONS

The strong covariation of menstrual and bowel symptoms, along with the overlap in diagnoses of DYS and function bowel disorder, suggest a common physiological basis.

Modeling and reinforcement of the sick role during childhood predicts adult illness behavior

Previous studies suggest that the ways in which parents respond to children's health complaints (reinforcement) and the ways in which they cope with their own illnesses (modeling) influence the frequency of symptoms, disability days, and health care visits made by these children when they grow up. However, previous studies have not controlled for the mediating influence of stress, neuroticism, and physical examination findings. This study investigated the influence of childhood social learning on adult illness behavior in 383 women aged 20 to 40 years. Illness behavior was measured prospectively for 12 months by the frequency of symptoms, disability days, and physician visits for menstrual, bowel, and cold (upper respiratory) symptoms. Childhood reinforcement and modeling was measured retrospectively by validated questionnaires. Other independent variables were stress, neuroticism, and selected demographic variables. Multiple regression analysis was used to assess the relative contribution of each independent variable to each category of illness behavior. The principal findings were as follows. First, childhood reinforcement of menstrual illness behavior significantly predicted adult menstrual symptoms and disability days, and childhood reinforcement of cold illness behavior significantly predicted adult cold symptoms and disability days. These effects were independent of stress and neuroticism. Second, childhood reinforcement scales were useful to predict which functional disorders (dysmenorrhea or irritable bowel syndrome) these subjects had even after we controlled for stress and neuroticism.

Forceps and vacuum extraction

The proper use of forceps or vacuum extractor, or both, remains a safe and effective modality in achieving the universal goal of a healthy mother and baby. Their use requires continued experience, sharing of information, and possibly attention to subtleties of design. This review looks at the current situation with special emphasis on side effects and selection issues as found in the recent literature.

Interleukin-2 transfected prostate cancer cells generate a local antitumor effect in vivo

In an effort to stimulate host-mediated antitumor response against prostate cancer in an animal model, highly malignant Dunning MAT-LyLu rat prostate carcinoma cells were transfected with the interleukin-2 (IL-2) cDNA, resulting in their ability to secrete large amounts of biologically active IL-2. Although parental cells form lethal tumors when injected subcutaneously into syngeneic hosts at doses of > or = 5,000, injections of IL-2 secreting cells initially formed tumors and regressed completely in each of over 200 animals at all doses tested (10(4)-8 x 10(7) cells). Mixtures of parental and IL-2 transfected cells were similarly rejected, demonstrating the non-cell autonomous nature of the response. Histological analysis of regressing tumors revealed a vigorous, predominantly lymphocytic and macrophage infiltrate at day 2 and marked tumor necrosis by day 6. Immunohistochemical staining of infiltrating lymphocytes at this latter time point demonstrated numerous T cells bearing either CD4 or CD8 surface markers, suggesting these cells as possibly mediating the tumor rejection. The ability of athymic mice to reject the IL-2 secreting tumor cells, however, suggests a non-T-cell-mediated mechanism. Although splenic natural killer (NK) activity is increased following injection of IL2 secreting tumor cells, this activity appears to be unnecessary for tumor elimination since syngeneic animals injected with asialo-GM1 antiserum to decrease NK activity also rejected IL-2 transfected cells, albeit slightly less effectively than untreated animals. Immunization of animals with subcutaneous injections of IL-2 transfected cells protected animals against a subsequent challenge of 10(4) wild-type cells 1 to 2 weeks later in 19 of 51 cases; however, immunization did not confer protection against larger doses of parental tumor. These studies indicate that high local concentrations of IL-2 stimulate the elimination of large local burdens of prostate cancer in this model system, and this elimination results in a weak, but detectable systemic immune response against wild-type prostate cancer cells.

Retinal blood flow after superior cervical ganglionectomy: a laser Doppler study in the cynomolgus monkey

There is a conflicting literature regarding the possible presence of adrenergic innervation of the retinal circulation. The effect of a histologically confirmed left superior cervical ganglionectomy on the total retinal blood flow in eight anaesthetised female cynomolgus monkeys was determined. Near total unilateral ocular sympathetic denervation was confirmed by ipsilateral miosis, supersensitivity of pupillary dilatation to topical phenylephrine and pupillary hyporesponsiveness to topical hydroxyamphetamine. Retinal vein diameters were measured from monochromatic photographs, maximum red cell velocities (Vmax) were measured with a helium-neon laser, using a bidirectional laser Doppler velocimeter technique, and the total retinal blood flow in each eye was determined by summation of measurements of flow in individual retinal veins. Mean (SEM) total retinal blood flow was 32.93 (1.49) and 30.41 (1.86) microliters/min in the eight sympathectomised and normal eyes respectively; the 9% (5%) difference was not statistically significant. Our study suggests that pharmacologically confirmed sympathetic denervation has little if any effect on resting total retinal blood flow.

Chronic pelvic pain

Chronic pelvic pain is a complex problem with a long history of attempts to elucidate the cause and to design effective therapies. This review is structured around recent articles in the field which contribute to our understanding, support certain therapeutic approaches, or describe a specific case. The pain aspects of endometriosis are included for their contribution to our understanding of pain and the difficulty encountered in managing these patients.

A comparison of serum and vaginal dialysate concentration of 13,14-dihydro-15-keto-PGF2 alpha in women undergoing 1st trimester therapeutic abortions

13,14-Dihydro-15-keto-PGF2 alpha(PGFM) levels in serum and vaginal secretion, before, one hour, and 24 hours post abortion were measured in 13 women from 8 to 12 weeks pregnant. The mean metabolite levels in the blood were 61.2 pg/ml pre-termination, 73.1 pg/ml and 121.4 pg/ml one hour and 24 hours post-termination. The vaginal dialysate means were 136.7 pg/ml, 425.7 pg/ml, and 211.7 pg/ml respectively.

Homozygous deletion and frequent allelic loss of chromosome 8p22 loci in human prostate cancer

Allelic loss studies have been instrumental in identifying tumor suppressor gene loci in a variety of cancers. In this study we analyzed prostate cancer specimens from 52 patients for allelic loss using 8 polymorphic probes for the short arm of chromosome 8. Overall, 32 of 51 (63%) informative tumors showed loss of at least one locus on chromosome 8p. The most frequently deleted region is observed at chromosome 8p22-8p21.2. Loss of one allele is identified in 14 of 23 (61%) tumors at D8S163, in 15 of 32 (47%) tumors at lipoprotein lipase, and in 20 of 29 (69%) tumors at MSR, all on 8p22. Loss of one allele is identified in 16 of 27 (59%) tumors at D8S220 at 8p21.3-8p21.2. In addition to frequent loss of one allele at the MSR locus, one metastatic prostate cancer sample demonstrated homozygous deletion of MSR sequences. Loci telomeric and centromeric to this region are largely retained. A chromosome 8p deletion map is constructed and defines the smallest region of overlap to a 14-cM interval at 8p22 between D8S163 and lipoprotein lipase, flanking the MSR locus. Evidence of chromosome 8q multiplication at locus D8S39 was detected in 5 of 32 (16%) tumors, all of which demonstrated loss with at least one probe on chromosome 8p. This study extends the previous finding of frequent loss of chromosome 8p in prostate cancer by defining a common region of loss of heterozygosity at 8p22 and a homozygous deletion of the MSR locus contained within this region. This is the first homozygous deletion identified in the genome of a human prostate cancer and the highest rate of loss yet reported on chromosome 8p in cancer. These results strongly suggest the presence of a tumor suppressor gene in this region which is frequently inactivated in prostate cancer.