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R S Epstein

Publications and source records attributed to R S Epstein.

At least 37 records · Page 2Linked to original sources
PubMed1997

Excess mortality attributable to hip fracture in white women aged 70 years and older.

OBJECTIVE: The purpose of this study was to estimate the excess mortality attributable to hip fracture. METHODS: The 6-year survival rate of community-dwelling White female hip fracture patients aged 70 years and older entering one of seven hospitals from 1984 to 1986 (n = 578) was compared with that of White female respondents aged 70 years and older interviewed in 1984 for the Longitudinal Study on Aging (n = 3773). RESULTS: After age, education, comorbidity, and functional impairment were controlled, the mortality differential between the two groups accumulated to an excess among hip fracture patients of 9 deaths per 100 women 5 years postfracture. Among those with three or more functional impairments or one or more comorbidities, the excess was 7 deaths per 100: the effect of the fracture had disappeared in these groups by 4 years. In contrast, those with two or fewer impairments and those with no comorbidities had a continuing trend of increased mortality, with an excess of 14 deaths per 100 by 5 years. CONCLUSIONS: There is an immediate increase in mortality following a hip fracture in medically ill and functionally impaired patients, whereas among those with no comorbidities and few impairments, there is a gradual increase in mortality that continues for 5 years postfracture.

Aged↗
PubMed1996

From outcomes research to disease management: a guide for the perplexed.

Outcomes research is a rapidly evolving field that incorporates epidemiology, health services research, health economics, and psychometrics. Measurement of clinical and other outcomes has become increasingly important to the stakeholders in a rapidly changing health care environment. The desire to improve outcomes and control costs has stimulated greater interest in cost-effectiveness studies, which determine how well effective therapies work in the usual practice setting and how much they cost. The application of outcomes principles to the practices of health care providers has resulted in efforts to implement disease management programs. Unlike traditional programs carried out by physicians, these new efforts are based on systematic population-based approaches to identifying persons at risk, intervening with specific programs of care, and measuring clinical and other outcomes. The new efforts depend heavily on modern information systems.

Algorithms↗
PubMed1996

Cholesterol-reduction intervention study (CRIS): a randomized trial to assess effectiveness and costs in clinical practice.

BACKGROUND: The 1988 US National Cholesterol Education Program Expert Panel Report recommended initial treatment with niacin or bile acid sequestrants, followed by other agents if needed, to lower low-density lipoprotein cholesterol (LDL-C) levels in hypercholesterolemic patients who require drug therapy. It is unknown how the effectiveness and costs of such an approach ("stepped care") compare in typical clinical practice to those of initial therapy with lovastatin. PATIENTS AND METHODS: We randomly assigned 612 patients, aged 20 to 70 years, who met 1988 National Cholesterol Education Program guidelines for drug treatment of elevated LDL-C level and had not previously used cholesterol-lowering medication, to either a stepped-care regimen or initial therapy with lovastatin (both n=306). The study, conducted at Southern California Kaiser Permanente, was designed to approximate typical practice: provider compliance with treatment plans was encouraged but not enforced, and patients paid for medication as they customarily would. RESULTS: At 1 year, the decline in mean LDL-C level was significantly greater among patients assigned to initial treatment with lovastatin (22% vs 15% for stepped care; P<.001), as was the number who attained goal LDL-C level (</= 4.14 mmol/L [</= 160 mg/dL], or </= 3.36 mmol/L [</= 130 mg/dL] if coronary heart disease or two or more risk factors were present) (40% vs 24%; P<.001). The increase in mean high-density lipoprotein cholesterol levels was significantly greater in the stepped-care group, however (8% vs 1% for lovastatin; P<.001). Patients who were randomized to stepped care were more likely to report substantial bother caused by side effects (30% vs 16% for lovastatin; P<.001) and discontinuation of therapy at 1 year (28% vs 18%, respectively; P<.01). Costs of care were $333 higher per patient in the lovastatin group ($786 vs $453; P<.001). CONCLUSIONS: A stepped-care regimen beginning with niacin is less costly than initial therapy with lovastatin, but also less effective in lowering LDL-C level. While it is more effective in increasing high-density lipoprotein cholesterol levels, the tolerability of such a regimen may be a problem.

Adult↗
PubMed1996

Determinants of premenopausal bone mineral density: the interplay of genetic and lifestyle factors.

Bone mineral density (BMD) is a reflection of both genetic and lifestyle factors. The interplay of genetic (vitamin D receptor [VDR] gene polymorphisms) and lifestyle factors on BMD at the lumbar spine and proximal femur was examined in 470 healthy premenopausal women, aged 44-50 years, using a Hologic QDR 2000 densitometer. The objective of this study was to examine the genetic and lifestyle determinants of premenopausal BMD. Each participant was genotyped for BsmI polymorphism at the VDR gene locus. The presence of a restriction site within VDR, specified as bb (189, 40.2%) (n, %) was associated with reduced spinal BMD, whereas absence of this site in BB (97, 20.6%) conferred greater spinal BMD, as did the genotype Bb (184, 39.1%). Associations between smoking, alcohol use, oral contraceptives, education level, multivitamins, number of children, degree of obesity, body weight, physical activity, dietary calcium intake, and VDR genotype to BMDs were examined. VDR genotype, body weight, degree of obesity, physical activity, and dietary calcium intake were all significant determinants of BMD. The association of VDR genotype with BMD at the femoral neck appeared to be modified by calcium intake (BB and Bb: 0.797 +/- 0.11 g/cm2 vs. 0.844 +/- 0.11 g/cm2, interaction term, p = 0.06) for low (< 1036 mg/day) and high (> or = 1036 mg/day; upper quartile) calcium intakes, respectively. A similar trend was demonstrated for physical activity. These findings suggest that prophylactic interventions aimed at achieving and maintaining optimal BMD, such as greater calcium intake or physical activity, may be important in maximizing one's genetic potential for BMD.

Adult↗
PubMed1996

Impact of the global on patient perceivable change in an asthma specific QOL questionnaire.

One method of defining clinically meaningful changes in quality of life domain scores is 'anchoring', that is, relating changes in domain scores to more easily understood changes on a global question. Although this methodology has been used to assess changes in domain scores in clinical trials, the choice of global question has not undergone much scrutiny. This study examines the impact of two global questions on the definition of clinically meaningful changes in an asthma specific quality of life (ASQOL) questionnaire. We tracked 343 patients with mild to moderate asthma symptoms in a placebo controlled clinical trial. The patients responded to the ASQOL questionnaire, and answered two global questions; one assessing how well their asthma is controlled, and the other assessing the change in their asthma since the start of the study. Changes in each domain of the ASQOL questionnaire were related to each global question. Since each global question led to different definitions of what constituted meaningful change, we concluded that the wording of the global question can affect the definition of meaningful change in the ASQOL domain scores. Thus, when identifying meaningful changes, it is important to state the global question so that the context of the meaningful change is correctly understood.

Adult↗
PubMed1996

The association between vitamin D receptor gene polymorphisms and bone mineral density at the spine, hip and whole-body in premenopausal women.

The genetic influence on bone mineral density (BMD) is thought to be mediated in part by alleles at the vitamin D receptor (VDR) locus. In order to assess the effect of VDR on BMD in premenopausal women, we studied 470 healthy white subjects, aged 44-50 years, participating in the Women's Healthy Lifestyle Project. Each participant was genotyped for the BsmI polymorphism at the VDR gene locus. BMD at the lumbar spine, hip and whole-body, and the whole-body soft tissue composition, were measured cross-sectionally using a Hologic QDR 2000 densitometer. The presence of a polymorphic restriction site at the VDR gene locus was specified as b, whereas absence of this site was B. The frequency distribution of the VDR genotype was: bb, 20.6%; Bb, 39.1%; and BB, 40.2%. Spinal BMD (mean +/- SD) was significantly lower in women with VDR genotype BB (1.038 +/- 0.11 g/cm2) as compared with those with genotype bb (1.069 +/- 0.12 g/cm2, p < 0.05). Trochanter BMD was 2.7% lower in those with genotype BB versus bb (0.685 +/- 0.10 g/cm2 vs 0.708 +/- 0.09 g/cm2). A similar trend was shown at each subregion of the hip, but not at the whole-body. In premenopausal women, allelic status at the VDR locus contributed to variations in spinal and trochanteric BMDs, but the absolute difference in BMDs was small, amounting to 0.26 and 0.23 standard deviations, respectively. It is concluded that in this population of healthy premenopausal women there was a significant association between polymorphisms at the VDR gene locus and both spinal and trochanteric BMDs, yet no association was demonstrated for the whole-body BMD.

Adult↗
PubMed1996

Determinants of vertebral fracture prevalence among native Japanese women and women of Japanese descent living in Hawaii.

Age-adjusted prevalence of vertebral fracture has been reported to be higher among native Japanese women than among women of Japanese descent living in Hawaii. In this cross-sectional population-based study, we examined a variety of potential risk factors for associations with prevalent vertebral fractures and investigated whether these factors could explain the difference in vertebral fracture prevalence between native Japanese and Japanese-American women. Spine radiographs and data on spine bone mineral density (BMD) and other potential risk factors were collected among 802 Japanese women aged 50-88 years living in Hiroshima and 840 Japanese-American women aged 52-88 years living in Hawaii. In logistic regression analysis, BMD was a major predictor of prevalent vertebral fracture. In linear regression models, weight, age, and menstrual history (age at menopause or years between menarche and menopause) were significantly associated with BMD and thus might contribute to fracture risk indirectly through their effects on BMD. However, age and menstrual history provided additional and complementary information about fracture prevalence after adjusting for BMD. These variables together explained much of the difference in vertebral fracture prevalence between the two study populations. We conclude that the observed difference in age-adjusted prevalence of spine fracture between native Japanese and Japanese-American women was accounted for primarily by the differences in BMD, duration of estrogen exposure, and/or duration of estrogen deficiency. Thus, current BMD is a major but not the sole risk factor for vertebral fractures. Age-related and menopause-related mechanisms may also play an important role in spine fracture independent of BMD.

Absorptiometry, Photon↗
PubMed1995

Radiographic absorptiometry in the diagnosis of osteoporosis.

Radiographic absorptiometry (RA) is a technique for bone mass measurement from radiographs of peripheral sites, most commonly the hand or heel. The principle was first described in 1939, and RA became relatively widely used as a research technique in the 1960s, although interest in RA subsequently dwindled as precise nonradiographic densitometry techniques became available. Recently, however, computerized image processing has been applied to radiography, with the result that current RA techniques applicable to a routine clinical setting are as precise and accurate as dual-energy or single-energy x-ray absorptiometry (DXA or SXA). In addition, recent studies demonstrate that the strength of association between low bone mass measured by RA and fracture risk is comparable to that for other forms of bone mass measurement. The relatively low cost and lack of need for specialized equipment make RA a highly attractive option for the diagnosis of osteoporosis that is available to specialist and nonspecialist physicians alike.

Absorptiometry, Photon↗
PubMed1995

Body composition and bone mineral density in premenopausal and early perimenopausal women.

Body composition appears to be an important determinant of bone mineral density (BMD). BMD at the femoral neck, lumbar spine, and whole-body and the whole-body soft-tissue composition were measured cross-sectionally in 334 healthy premenopausal and early perimenopausal women, aged 44-50 years, using a Hologic QDR densitometer. Correlations between lean mass and BMD at the hip, spine, and whole-body were greater (r = 0.40, r = 0.44, and r = 0.45, respectively, p < 0.0001) than those for fat mass (r = 0.19, r = 0.16, and r = 0.16, respectively, p < 0.01). There was a significant linear trend in femoral BMD from the lowest to highest category of lean mass (0.75 +/- 0.10 g/cm2, 0.80 +/- 0.10 g/cm2, and 0.86 +/- 0.09 g/cm2, p < 0.0001). Similar trends were demonstrated for spinal and whole-body density. For categories of fat mass, there was a significant linear trend at the hip (0.78 +/- 0.10 g/cm2, 0.79 +/- 0.10 g/cm2, and 0.83 +/- 0.10 g/cm2, p = 0.0106), but not at the spine or whole body. There was a 5.00% (3.62, 6.38; 95% confidence limits) difference in hip BMD per unit (standard deviation) of lean mass, while only a 0.73% (-0.66, 2.11) difference in hiP BMD per unit (SD) of fat mass. Differences in BMD were examined by categories of lean and fat mass (low, medium, high) for a total of nine possible combinations of lean and fat measures. BMD at the hip, spine, and whole-body were significantly higher in those with high lean mass than in those with low lean mass, irrespective of fat mass. Women with high lean/low fat had similar hip, spinal, and whole-body BMD as those with high lean/high fat, despite their significantly lower body weight (62.5 +/- 3.3 kg vs 85.7 +/- 5.4 kg, respectively, p < 0.0001). In premenopausal and early perimenopausal women, body weight alone may not be associated with increased bone mass unless a significant proportion of that weight is comprised of lean mass. The stronger association between lean mass and BMD than that for fat mass may be attributed to differences in determinants of lean mass, such as exercise, lifestyle factors, estrogen levels, or a combination of these factors.

Adult↗
PubMed1995

Area under the curve: a metric for patient subjective responses in episodic diseases.

Herpes zoster manifests as a characteristic painful rash that resolves within 2 months of initial presentation in 90% of patients. As pain is a hallmark of the disease, the severity of an episode can be described by the magnitude and duration of pain. The Brief Pain Inventory (BPI) was used to follow the daily and weekly amount of pain reported by 50 patients with herpes zoster. Results demonstrate that the BPI is a reproducible, responsive and valid measure of pain due to herpes zoster. From the individual responses on the BPI, the area under the curve (AUC) for each patient was derived from the pain reported on sequential administrations of the BPI. This metric was simple to calculate, easy to explain and captured two dimensions of this episodic disease (magnitude and duration of pain) in a single continuous measure. AUC could prove useful in the application of patient response data to intervention trials in diseases that are of an episodic nature.

Herpes Zoster↗
PubMed1995

A randomized trial to assess effectiveness and cost in clinical practice: rationale and design of the Cholesterol Reduction Intervention Study (CRIS).

To compare the effectiveness and costs of two alternative approaches to the treatment of hypercholesterolemia, a prospective randomized trial is being undertaken at Southern California Kaiser Permanente, a large health maintenance organization. Six hundred and twelve patients with postdiet LDL cholesterol (LDL-C) levels in the range of 190-230 mg/dl (or 160-230 mg/dl for those with coronary heart disease or two or more coronary risk factors) were randomized to a stepped-care regimen (initial treatment with niacin followed by other agents if needed) or to initial use of lovastatin, an HMG-CoA reductase inhibitor. All patients are being followed for 1 year. The study seeks to approximate conditions of typical clinical practice: provider compliance with these plans of treatment is encouraged but not enforced and patients pay for medication as they customarily would. Principal outcomes of interest include the proportion of participants who achieve goal LDL-C at one year, the mean change in total cholesterol and LDL-C levels between baseline and the end of follow-up, and the costs of cholesterol-lowering therapy.

Adult↗
PubMed1995

Vertebral fracture prevalence in women in Hiroshima compared to Caucasians or Japanese in the US.

BACKGROUND: Although vertebral fractures are very common among elderly Caucasian women, no studies have compared the prevalence to that among Asian populations. Any observed differences in prevalence might lead to the identification of important environmental and/or genetic factors. We therefore compared the prevalence of vertebral fractures among US Caucasians to native Japanese and Japanese immigrants in Hawaii using a standardized approach. METHODS: Spinal radiographs of women aged > 50 years were obtained from native Japanese in Hiroshima, Japanese-Americans in Hawaii, and North American Caucasians in Minnesota between 1982 and 1991. Fractures were defined as vertebral heights > 3 standard deviations (SD) below the vertebra-specific mean. RESULTS: Compared to Japanese-Americans, odds ratios (OR) and 95% confidence intervals (CI) for prevalent vertebral fractures were 1.8 (95% CI: 1.3-2.5) for native Japanese women and 1.5 (95% CI: 1.1-2.1) for Minnesota Caucasians. The OR tended to be higher when comparing the prevalence of two or more fractures per person: OR = 3.2 (95% CI: 2.0-5.3) for native Japanese and OR = 1.9 (95% CI: 1.2-3.2) for Minnesota Caucasians. Similar results were observed for native Japanese using a fracture definition of > or = 4 SD below the mean, but the OR for Caucasians was reduced to 1.2 (95% CI: 0.6-2.3). CONCLUSION: The observation that, among these three populations, hip fracture incidence is lowest but spine fracture prevalence is greatest among native Japanese suggests that different risk factors may be responsible.

Age Factors↗
PubMed1995

Development of a brief 24-hour migraine-specific quality of life questionnaire.

The objective of this study was to develop a questionnaire to assess the short-term quality of life decrements associated with an acute migraine headache attack. A total of 101 potential quality of life items were generated by interviewing migraineurs and migraine specialists and reviewing the literature. To reduce the items, 76 migraineurs (18 years and older) were asked to identify which of the 101 items affected their quality of life in the 24 hours following onset of a migraine and to rate them on a five-point scale from "not very important" to "extremely important." Reduction of the 101 items to a 15-item questionnaire was performed by evaluating the results of subject-perceived importance (number of times an item was chosen x mean importance score) in combination with principal components analysis. Five domains were identified: (1) work functioning, (2) social functioning, (3) energy/vitality, (4) migraine headache symptoms, and (5) feelings and concerns. Each domain has three items and the correlation between the five domains, as measured by the Spearman correlation coefficient, ranged from 0.08 to 0.38 suggesting minimal overlap. The brief migraine quality of life questionnaire was pilot-tested in two groups of 10 migraineurs and revised to improve clarity.

Adult↗
PubMed1995

Validation of a new quality of life questionnaire for acute migraine headache.

A brief migraine-specific quality of life questionnaire was developed to assess the quality of life decrement associated with an acute migraine attack in the 24-hour period following headache onset. The migraine quality of life questionnaire has 15 questions across five domains (work functioning, social functioning, energy, concerns, and symptoms). A prospective, observational study was conducted to evaluate the characteristics of internal consistency, construct and discriminant validity, and responsiveness of the migraine quality of life questionnaire. One hundred thirty-eight subjects with migraine were recruited. One hundred seven subjects completed a baseline and a 24-hour postmigraine quality of life questionnaire, along with a migraine diary for recording headache severity, activity limitation, associated symptoms, duration of headache, and use of migraine medication. All five migraine quality of life questionnaire domains showed good internal consistency (Cronbach's alpha, 0.74-0.95). The strongest correlations were seen between activity limitation and associated symptoms and the migraine quality of life questionnaire work, social, and energy domains. Significant differences in mean questionnaire scores between subjects were found with frequency of medication use, global change in symptoms, headache duration, and severity. All five domains showed significant responses within subjects from a migraine-free period to an acute migraine period (P < 0.0001). In summary, the migraine quality of life questionnaire showed good internal consistency, construct and discriminant validity, and responsiveness to acute migraine attacks.

Acute Disease↗
PubMed1994

When should bone density measurements be repeated?

We calculated how long to wait before repeating bone mineral density (BMD) measurements to reassess fracture risk. Correlation results from serial measurements of 495 postmenopausal Japanese-American women were used to estimate 95% confidence intervals (CI) for future BMD. After 7 years of follow-up, BMD correlations with the initial measurement ranged between 0.81 and 0.94, depending on age group and measurement site. In this analysis, the period between measurements was defined as the time required for the lower 95% CI to fall below the BMD value corresponding to doubling of fracture risk. Progressive bone loss causes fracture risk to double after 10 years, on average. However, the 95% CIs indicate that a second BMD measurement will detect risk doubling after only 2 or 3 years for some women. For untreated, early postmenopausal women, the period between measurements was approximately 2-5 years for the radius and 4-6 years for the calcaneus, depending on the initial BMD level. The period was approximately 1 year longer for women age 60 and older. Treatments that halve the bone loss rate would increase the period by 1-3 years. In the absence of a second measurement of BMD, the CI will continue to expand with time, corresponding to a wider range in risk between individuals, and a greater proportion of women will be at increased fracture risk. Obtaining a second BMD measurement pinpoints the patient's status within the precision of the measurement. We conclude that repeated BMD measurements will provide a more accurate estimate of fracture risk than a single, baseline measurement.

Age Factors↗
PubMed1994

Pain and disability associated with new vertebral fractures and other spinal conditions.

Although vertebral fractures are common among older women, little is known about associations with pain and disability. In this prospective study, fractures which occurred after the initial radiograph were strong predictors of back pain and disability at the end of followup, with odds ratios (OR) of approximately 4-5. Other, independently significant predictors were self-reported history of (1) disk disease (OR = 3-9), (2) traumatic back injury (OR = 4-7), and (3) spinal arthritis (OR = 3-6). In longitudinal analyses, new fractures were associated (OR = 6.4; 95% CI = 2.6, 15.6) with increases in back pain frequency (relative to pre-fracture levels). The association with prevalent fractures was weaker, and not significant (OR = 1.7; 95% CI = 0.5, 5.6). The pain frequency index increased approximately 3-fold, relative to pre-fracture levels. At the end of followup (mean = 3.5 years), the index was still two times greater than baseline. We conclude that associations with back pain and disability are greater in magnitude for new vertebral fractures than for prevalent fractures.

Adult↗