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H B Rubins

Publications and source records attributed to H B Rubins.

32 records · Page 2Linked to original sources
PubMed1995

Cholesterol in patients with coronary heart disease: how low should we go?

CLINICAL PROBLEM: To examine the evidence supporting the recent National Cholesterol Education Program (NCEP) recommendation that low to moderate levels of cholesterol should be aggressively managed in patients with coronary heart disease (CHD). METHODS: Cohort studies and clinical trials with angiographic or clinical endpoints, that included CHD patients with low to moderate levels of cholesterol, were systematically identified through a MEDLINE search and critically reviewed. SYNOPSIS: None of the cohort studies show that a moderate level of cholesterol confers significantly increased risk of CHD death, although a pooled relative risk of 1.14 (95% CI 1.08 to 1.4) suggests that there may be a slight excess risk. Of five angiographic trials of CHD patients with moderate levels of cholesterol, two demonstrated no improvement in angiographic endpoints with intensive lipid-lowering therapy and the other three are difficult to interpret since they included other interventions in addition to the cholesterol-lowering regimen. No large clinical trial with clinical endpoints has been reported for CHD patients with low to moderate levels of cholesterol. RECOMMENDATIONS: The recommendation to treat CHD patients who have low to moderate levels of cholesterol with diet or drugs is not based on convincing evidence of efficacy. This is in clear contrast to the recommendation for CHD patients with high levels of cholesterol, for whom there is definitive clinical trial evidence of benefit from cholesterol-lowering therapy. While we await clinical trial results for CHD patients with low to moderate levels of cholesterol, clinicians and patients must consider the possible disadvantages of therapy in relation to the uncertain benefit.

Anticholesteremic Agents↗
PubMed1994

From clinical trials to clinical practice: generalizing from participant to patient.

This paper uses the report of the Lipid Research Clinics Coronary Primary Prevention Trial as an example of how clinicians apply the results of clinical trials to their practice. Clinical trials influence practice primarily to the extent that they eventually become incorporated into the generally accepted standard of medical care. To a lesser extent, physicians are influenced by their own interpretation of clinical trial results. Since physicians usually do not have the leisure or the technical expertise to evaluate primary data critically, their conclusions are heavily influenced by the authors' sometimes overoptimistic interpretation of the results. Therefore, practicing clinicians often overestimate the benefits of a therapy and generalize the results of a trial too broadly. Ideally, physicians should base treatment decisions on their knowledge of the pathophysiology of the disease, the mechanism of action of the proposed treatment, and the clinical characteristics of the individual patient while informing their decision with a critical understanding of the results of relevant trials.

Cholesterol↗
PubMed1994

Modification of the dextran-Mg2+ high-density lipoprotein cholesterol precipitation method for use with previously frozen plasma.

Although dextran-Mg2+ precipitation produces accurate and precise results for high-density lipoprotein (HDL) cholesterol in fresh plasma and serum, precipitation of frozen specimens with triglycerides > 2.26 mmol/L (> 200 mg/dL) is difficult. We developed a modification that dilutes thawed samples by 35% and increases dextran-Mg2+ reagent to 15% of sample volume. Standard precipitations were performed on 62 fresh EDTA-treated plasma specimens; supernatant solutions were analyzed fresh and after freezing. Standard and modified methods were also performed on thawed, paired plasmas. In specimens with triglycerides < or = 2.26 mmol/L, HDL cholesterol results for all methods were similar. For triglycerides > 2.26 mmol/L, however, bias and precision were significantly affected by freezing, and 38.5% of samples with standard precipitation required additional procedures to produce clear supernatant solutions. HDL cholesterol concentrations for thawed samples with standard precipitation were significantly greater than for fresh samples (P < 0.02), but those for the modified method were not different from fresh samples, and only one specimen required additional steps to produce a clear supernate.

Chemical Precipitation↗
PubMed1993

Rationale and design of the Department of Veterans Affairs High-Density Lipoprotein Cholesterol Intervention Trial (HIT) for secondary prevention of coronary artery disease in men with low high-density lipoprotein cholesterol and desirable low-density lipoprotein cholesterol.

Although a large body of epidemiologic evidence suggests that low levels of high-density lipoprotein (HDL) cholesterol are strongly associated with an increased risk of coronary artery disease (CAD), no large-scale clinical trials focusing on this association have been reported. This report describes the rationale and design of the Department of Veterans Affairs HDL Intervention Trial (HIT), a multicenter, randomized, controlled clinical trial designed to determine whether lipid therapy reduces the combined incidence of CAD death and nonfatal myocardial infarction in men with established CAD who have low levels of HDL cholesterol with "desirable" levels of low-density lipoprotein (LDL) cholesterol. Twenty-five hundred men with CAD and HDL cholesterol < or = 40 mg/dl, LDL cholesterol < or = 140 mg/dl, and triglycerides < or = 300 mg/dl are being recruited at 20 Department of Veterans Affairs medical centers, randomized to either gemfibrozil or placebo, and followed in a double-blind manner for an average of 6 years. In this population, gemfibrozil is expected to increase HDL cholesterol by 10 to 15%, have a negligible effect on LDL cholesterol, and lower triglycerides by 30 to 40%. Because an estimated 20 to 30% of patients with CAD have a low HDL cholesterol as their primary lipid abnormality, the results of this trial are expected to have far-reaching clinical implications.

Adult↗
PubMed1992

Effect of reduction of plasma triglycerides with gemfibrozil on high-density-lipoprotein-cholesterol concentrations.

The aim of this study was to test the hypothesis that the plasma triglyceride (TG) concentration must be reduced below approximately 0.85-1.13 mmol l-1 (75-100 mg/dl-1) in order to achieve a substantial increase in plasma high-density-lipoprotein-cholesterol (HDL-C) levels. The study design consisted of a non-randomized clinical trial, which was conducted at an out-patient clinic at a university-affiliated VA Medical Center. The participants consisted of 55 ambulatory middle-aged men with a baseline fasting HDL-C concentration of less than or equal to 1.17 mmol l-1 (45 mg dl-1) and baseline TG in the range 1.13-5.6 mmol l-1 (100-500 mg dl-1). Subjects were treated with gemfibrozil, 600 mg twice a day for 3 months. Fasting plasma HDL-C, TG, low density lipoprotein-cholesterol, and total cholesterol were measured at 1-month intervals for 3 months. Subjects were divided into three groups on the basis of TG level achieved on therapy: Group I (n = 14), TG less than 0.85 mmol l-1 (75 mg dl-1); Group II (n = 20), TG 0.86-1.41 mmol l-1 (76-125 mg dl-1); Group III (n = 21), TG greater than 1.41 mmol l-1 (125 mg dl-1). The mean increase in HDL-C in Group I was 0.20 mmol l-1 (7.8 mg dl-1), a significantly (P = 0.0067) greater increase than was observed in the other two groups. There was no correlation between the magnitude of change in TG and the magnitude of change in HDL-C concentration in the group as a whole (Pearson's correlation coefficient, r = -0.06, P = 0.6). In conclusion, the increase in HDL-C levels observed with gemfibrozil therapy is associated with the absolute level of TG achieved by therapy. Substantial increases in HDL-C concentration might not be expected to occur consistently unless TG levels are reduced to values that are considered below the usually cited 'normal' range.

Cholesterol, HDL↗
PubMed1992

Distribution of lipid phenotypes in community-living men with coronary heart disease. High prevalence of isolated low levels of high-density lipoprotein cholesterol.

BACKGROUND: Risk factor modification, including treatment of dyslipidemias, has been recommended for the prevention of future coronary events in patients with coronary heart disease (CHD). Since the prevalence of various dyslipidemias among outpatients with CHD has not been well documented, the purpose of this study was to determine the frequency of specific lipid phenotypes among ambulatory men with CHD. METHODS: Lipid profiles were obtained in 255 men (mean age, 65.5 +/- 9.1 years) with CHD in three Veterans Affairs medical centers. Desirable levels of lipids were defined according to National Cholesterol Education Program guidelines as follows: low-density lipoprotein cholesterol (LDL-C) levels less than 3.36 mmol/L (130 mg/dL); high-density lipoprotein cholesterol (HDL-C) levels equal to or greater than 0.90 mmol/L (35 mg/dL); and triglyceride levels less than 2.83 mmol/L. RESULTS: Seventy-six percent of the group had one or more abnormalities on lipid profile: 51% had high LDL-C levels with or without abnormalities of HDL-C and/or triglyceride levels; 22% had low HDL-C levels with desirable levels of LDL-C; and 3% had hypertriglyceridemia without any cholesterol abnormalities. Normal lipid profiles were significantly more prevalent in subjects over the age of 65 years than in younger patients (40% vs 14%). CONCLUSIONS: These data suggest that (1) a high proportion of men with CHD have dyslipidemia, including 50% with LDL-C level elevations. For these men, the potential benefits of therapeutic intervention have been documented in clinical trials, although the cost-efficiency of wide-scale treatment has not been determined; (2) isolated hypertriglyceridemia is rare in this population; and (3) low HDL-C levels in association with desirable LDL-C levels are present in more than one fifth of male patients with CHD. Clinical trials focusing on this large group are urgently needed to determine whether efforts to raise HDL-C levels result in reduced cardiac morbidity and/or mortality.

Aged↗
PubMed1990

The medical day hospital. A new concept in ambulatory medical education.

The shift of patients from inpatient to outpatient settings as a result of various well-known economic, technologic, and demographic forces presents a challenge for internal medicine residency training programs. In response, we developed a new ambulatory site for education of medical students and residents. The Ambulatory Diagnostic and Treatment Center functions as a medical day hospital serving the needs of patients requiring intensive diagnostic or therapeutic interventions on a short-term basis. The center maintains many of the educational advantages of an inpatient service including block rotations of house officers, easy access to consultants and specialized services, and daily attending rounds while providing experience in outpatient management skills. This unit represents a new concept in ambulatory education and, if adaptable to other institutions, may be a valuable component of a broad ambulatory medicine curriculum.

Attitude of Health Personnel↗
PubMed1988

Discharge decision-making in a medical intensive care unit. Identifying patients at high risk of unexpected death or unit readmission.

In an attempt to identify clinical variables associated with unexpected death or unit readmission following discharge from a medical intensive care unit (MICU), 300 consecutive patients admitted to a MICU were prospectively identified and followed through their hospital stay. Of the 229 patients at risk, 37 (16 percent) experienced one or more unexpected unit readmissions (n = 30) or death (n = 7). In comparison to the patients without such complications (n = 192), these 37 patients differed with respect to age, diagnosis, and severity of illness on admission. In addition, these patients were sicker on initial unit discharge as manifested by higher heart and respiratory rates and lower hematocrit values. On multivariate analysis, age, acute physiology score on admission, and a diagnosis of upper gastrointestinal bleeding were independent predictors of unexpected outcome. It is concluded that patients at high risk for unit readmission or unexpected death are distinguished from other MICU survivors on several clinical parameters. Whether such information can be useful in individual discharge decisions is uncertain and requires further investigation.

Age Factors↗
PubMed1984

Adenocarcinoma and Barrett's esophagus. An overrated risk?

The risk of developing esophageal cancer in Barrett's esophagus has been estimated at about 10%. This estimate is based primarily on data concerning the prevalence of that association in series of hospitalized patients and autopsies--a practice that tends to exaggerate the risk. We have reviewed retrospectively our experience with 115 patients whom we treated for Barrett's esophagus between September 1962 and March 1983, and have distinguished our data on the prevalence of esophageal cancer from that on incidence. For 8 patients, we found both Barrett's esophagus and esophageal adenocarcinoma during the initial evaluations for a prevalence ratio of 7%. We followed 105 patients not found to have esophageal cancer initially for a total of 350 person-years. Only 2 patients developed adenocarcinoma during that follow-up period for an incidence of 1 case per 175 person-years. This incidence, although some 40-fold greater than that of the general population, is substantially lower than previously estimated. Routine endoscopic and histologic surveillance has been recommended for patients with Barrett's esophagus because of the alleged high incidence of esophageal cancer. Inasmuch as that incidence now appears to be low, we question the value of such surveillance for these patients.

Adenocarcinoma↗
PubMedDate not supplied

Complications of care in a medical intensive care unit.

OBJECTIVE: To determine the frequency and nature of complications of care in the medical intensive care unit (MICU). DESIGN: Prospective, observational study. SETTING: Seven-bed MICU in a teaching and referral VA hospital. PATIENTS: 295 consecutive patients admitted to the MICU during a ten-month study period. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Forty-two patients (14%, 95% confidence interval 13%, 16%) experienced one or more complications during their MICU stays. Compared with other MICU patients, those experiencing complications tended to be older (mean age +/- SD: 63.6 +/- 10.1 years vs 59.3 +/- 14.0 years, p less than 0.02) and more acutely ill (mean Acute Physiology Score +/- SD: 18.3 +/- 8.0 vs 12.5 +/- 8.0, p = 0.0001). These patients also had significantly longer MICU lengths of stay (mean +/- SD: 12.3 +/- 14.7 days vs 3.1 +/- 4 days, p less than 0.0001) and higher hospital mortality rates (67% vs 27%, p less than 0.001). The 67% mortality rate among patients with complications significantly exceeded the expected mortality rate of 46% (calculated from the APACHE risk equation). CONCLUSION: Complications of care in the MICU are not rare and may independently contribute to in-hospital mortality. The potential for complications must be recognized when considering ICU care.

Boston↗
PubMedDate not supplied

Educating men about prostate cancer screening. A randomized trial of a mailed pamphlet.

CONTEXT: Although evidence-based guidelines recommend that physicians inform men about prostate cancer screening, the most efficient way to do this is not known. OBJECTIVE: To evaluate whether a mailed educational pamphlet affected men's knowledge about early detection of prostate cancer. DESIGN: Randomized, controlled trial. SETTING: Primary care clinic of the Minneapolis VA Medical Center. PATIENTS: 342 men at least 50 years of age who responded to a mailed survey (overall response rate, 68%) and did not report a history of prostate cancer. INTERVENTION: "Early Prostate Cancer" pamphlet mailed to patients in the intervention group 1 week before their scheduled clinic appointments. OUTCOME MEASURES: Patients' responses to a survey mailed 1 week after their clinic appointments; prostate-specific antigen (PSA) testing determined from electronic medical records. RESULTS: Respondents were predominantly elderly white men (mean age, 71 years; 90% white) with chronic illnesses (48% described their health as "fair" or "poor"). Men who received the educational pamphlet were better informed than men in the usual care group, as measured by correct responses to the following three questions about prostate cancer screening: the natural history of prostate cancer (32% vs. 24%; P = 0.10), whether treatment lengthens lives of men with early prostate cancer (56% vs. 44%; P = 0.04), and accuracy of PSA testing (46% vs. 27%; P < 0.008). The overall proportion of correctly answered questions was greater in the intervention group (45% vs. 32%; P < 0.001). Testing for PSA in the year after the index clinic appointments did not differ significantly between the intervention group and the usual care group (31% vs. 37%; P > 0.2). CONCLUSIONS: Male veterans are poorly informed about the potential benefits and risks of prostate cancer screening. Although our mailed educational pamphlet enhanced knowledge only modestly, it was an inexpensive and easily implemented intervention.

Aged↗