Search PubMed⌕ Search

Biomedical subjects

R E Johnson

Publications and source records attributed to R E Johnson.

At least 127 records · Page 7Linked to original sources
PubMed1995

Medical care utilization among older HMO members with and without hypertension.

OBJECTIVES: To compare hospital utilization, health status, and sociodemographic characteristics of older persons with and without hypertension and to examine the nature of the association of hypertension with medical care utilization. DESIGN: A retrospective, nonexperimental study. SETTING: A large health maintenance organization (HMO), located in the Portland, Oregon and Vancouver, Washington areas, that provides comprehensive, prepaid benefits to its members. PARTICIPANTS: Approximately 4200 older (> or = 65 years) members enrolled in the Social HMO Demonstration Project. MEASUREMENTS: The dependent variables were (1) whether a member was hospitalized (0 = no; 1 = yes) and (2) the number of hospitalizations during the 12-month period before the return of the Health Status Form, a mail questionnaire. The predictor variables were high blood pressure and other medical conditions, health status, and sociodemographic characteristics. Patients classified as hypertensive were those who self-reported high blood pressure and who received two or more dispensings for antihypertensive medications. RESULTS: Older hypertensives were more likely than older nonhypertensives to have been hospitalized (odds ratio (OR) = 1.14 (95% CI 1.01, 1.27)), self-report their health as only good or fair (P < .001), self-report IADL functional limitations (P < .001), and to be younger than nonhypertensives (P < .001). Utilization differences were similar after controlling for patients' age and gender. Factors independently associated with an increased likelihood of hospitalization were male gender (OR = 1.14 (1.00,1.31)), age (OR = 1.35 (1.00,1.81)), poor (OR = 1.32 (1.02,1.72)) or fair (OR = 1.20 (1.01,1.44)) self-rated health status, functional limitations in activities of daily living (OR = 1.74 (1.48,2.03), and self-reported heart trouble (OR = 1.50 (1.34,1.68)), stroke (OR = 1.37 (1.15,1.64)), or cancer (OR = 2.89 (1.72,4.84)). Factors independently associated with a decreased likelihood of hospitalization were excellent self-reported health (OR = 0.65 (0.47,0.90)), no physical impairments (OR = 0.59 (0.48,0.72)), and no circulation problems (OR = 0.85 (0.74,0.98)). CONCLUSIONS: Older hypertensive patients had poorer self-reported health, more functional limitations, used more hospital services, and were not as old as nonhypertensive older patients. To the extent that general health is improved by treatment of hypertension, appropriate treatment of high blood pressure may not only improve health, it may also reduce medical care utilization. Our findings offer further support for hypertension prevention, detection, and treatment programs designed to reduce or minimize hypertension's later medical complications and to reduce future utilization.

Activities of Daily Living↗
PubMed1995

Linkage analysis of malignancy-associated sarcoidosis.

STUDY OBJECTIVE: To determine whether a reported association between sarcoidosis and malignancy can be supported. DESIGN: In this retrospective survey in a general community setting, we crossmatched the Kaiser Permanente Northwest Region (KPNW) Tumor Registry comprising 3 x 10(4) cases observed over 32 years against a sarcoidosis registry of 243 cases observed over 24 years. We used linkage criteria, eg, previously reported associated malignancies, late age onset of sarcoidosis, and close temporal proximity, to identify joint occurrences suggesting an etiologic relationship. We assessed the feasibility of detecting an association of sarcoidosis and Hodgkins disease (HD) by computing the required sample size based on incidence estimates of sarcoidosis and HD in this population. Medical records of 241 persons identified by the Tumor Registry as having HD were reviewed. SETTING: KPNW, a health maintenance organization. POPULATION: We studied 6.8 x 10(6) KPNW member-years from 1960 to 1992 at risk for malignancy; 5.6 x 10(6) member-years from 1971 to 1992 at risk for sarcoidosis. RESULTS: Six of the 11 (55%; 95% confidence interval, 26 to 84) correctly classified sarcoidosis and malignancy (S&M) cases met two or more linkage criteria. A seventh case, incorrectly classified as sarcoidosis, exhibited a necrotizing systemic granulomatous process, believed to represent a response to a fatal lymphoproliferative disorder. The mean age (40 years) of the 11 patients with S&M was 9 years higher than the mean age of the patients with sarcoidosis in the population from which they were drawn. The stage of sarcoidosis at diagnosis among the 11 S&M cases was exclusively 0 and I and thus divergent from expected values in this population. We found no instances of sarcoidosis accompanying HD. CONCLUSION: Linkage analysis provides evidence that S&M may be etiologically related in at least a quarter of cases in which both are present.

Adult↗
PubMed1994

Yeast DNA repair protein RAD5 that promotes instability of simple repetitive sequences is a DNA-dependent ATPase.

The RAD5 gene of Saccharomyces cerevisiae functions in postreplication repair of ultraviolet damaged DNA, and interestingly, it also has a role in increasing the instability of simple repetitive sequences in the genome. In contrast to DNA mismatch repair genes which function in maintaining constant length of repeat sequences, RAD5 promotes alterations in the length of repeat sequences. In this work, we purify the RAD5 protein to near homogeneity from yeast cells and show that it is a single-stranded DNA-dependent ATPase. The possible roles of RAD5 ATPase in postreplication gap filling and in increasing the incidence of length alterations of repeat sequences are discussed.

Adenosine Triphosphatases↗
PubMed1994

A controlled comparison of buprenorphine and clonidine for acute detoxification from opioids.

We compared the short-term efficacy of a high-dose, 3 day regimen of buprenorphine to a standard 5-day course of clonidine in attenuating the signs and symptoms of the acute opioid abstinence syndrome during rapid detoxification from heroin in 25 men and women admitted to a closed inpatient research ward for this randomized, double-blind, parallel-group trial. Among the 18 completers, there were no significant differences between the buprenorphine and clonidine groups on five subjective and six physiological measures. However, clonidine lowered blood pressure and buprenorphine provided more effective early relief of withdrawal symptoms.

Adult↗
PubMed1994

Replicating the chronic disease score (CDS) from automated pharmacy data.

Michael Von Korff and colleagues at the Center for Health Studies, Group Health Cooperative (GHC) of Puget Sound created a measure of chronic disease status (CDS) using automated outpatient pharmacy data. They reported the measure appeared to provide a stable and valid measure of health status. The availability of such a measure could become a new tool for a variety of applications, including screening, resource allocation, and quality assurance. The measure was replicated for its reliability and construct and predictive validity in the KPNW membership using automated pharmacy data. Reliability and validity were tested using correlation and regression techniques. The CDS showed test-retest reliability over time. It showed construct validity with the RAND-36 instrument and the BSI-8 depression screener. It showed predictive validity with health care visits and hospitalizations. The results were similar to those at GHC. The findings indicated that the CDS can serve, with certain precautions, as a readily accessible low cost measure of health status.

Chronic Disease↗
PubMed1994

Treated prevalence rates of severe mental illness among HMO members.

OBJECTIVES: The authors examined the extent to which health maintenance organizations (HMOs) enroll and provide services to people with severe mental illness. METHODS: The automated pharmacy system of a large HMO identified members who had received a prescription for an antipsychotic drug or lithium during the two-year study period (1986 and 1987). These data, combined with data from a 2 percent random sample of HMO members and from medical records, were used to identify members who satisfied DSM-III-R criteria for schizophrenia and bipolar disorder. Treated prevalence rates derived from these data were compared with estimated treated prevalence data obtained in the National Institute of Mental Health's Epidemiologic Catchment Area (ECA) survey. RESULTS: Although methodological complications and small sample sizes precluded a detailed comparison, the study found a significantly lower treated prevalence rate of schizophrenia among HMO members than in the ECA survey. The treated prevalence rate of bipolar disorder was also lower than the ECA rate, but the difference was not significant. CONCLUSIONS: The differences in treated prevalence rates seemed to be the result of different study methodologies and factors influencing HMO membership. The results underscore the need for a comprehensive study of the course of severe mental illness among HMO members.

Acute Disease↗
PubMed1994

Comparing health-related indicators of very old hypertensives and nonhypertensives in an HMO.

The purpose of this study was to determine if very old hypertensives (85 years of age and over) were sicker and in poorer health than very old nonhypertensives. The authors compared the frequency of comorbidities, medical care and drug use, self-reported functional and health status, and health-related behaviors of very old hypertensive and nonhypertensive health maintenance organization (HMO) enrollees. Very old male hypertensives were less healthy than very old male nonhypertensives, female hypertensives, and nonhypertensives. In contrast, very old female hypertensives were healthy or healthier than very old female nonhypertensives. Hypertension may be a more serious condition among the very old males than very old females, or treatment may be more efficacious (or prevalent) for very old female hypertensives. These relationships require further study to determine if treatment guidelines should differ by sex among very old hypertensives.

Activities of Daily Living↗
PubMed1994

Comparative study of ankle support devices.

The purpose of this study was to compare the ability of four commonly used ankle support devices (Active Ankle, Aircast Sport Stirrup, DonJoy Ankle Ligament Protector and Malleoloc) to restrict active inversion range of motion before and after exercise. The subjects also compared the devices on subjective characteristics, including stability, comfort, and ease of application and removal. Eighteen subjects had both ankles tested for maximum inversion on a specially designed measuring apparatus during three sessions: 1) before application, 2) before exercise with the support device, and 3) after exercise with the support device.

Adult↗
PubMed1994

The roadmap for clinical quality.

The Roadmap for Clinical Quality at Group Health Cooperative (GHC) of Puget Sound is a patient-focused, population-based, systematic, organizational effort designed to identify and improve key clinical processes for GHC enrollees. The underlying premise is that by improving clinical care processes and decreasing unnecessary practice variation, health, cost and patient satisfaction outcomes will improve, thereby increasing the value of the GHC product. Key clinical processes targeted for system-wide improvement are those for which there is demonstrable evidence that improving the care process will result in improved health outcomes and/or decreased cost.

Guidelines as Topic↗
PubMed1993

4,5-Dihydro-1-phenyl-1H-2,4-benzodiazepines: novel antiarrhythmic agents.

A series of 4,5-dihydro-1-phenyl-1H-2,4-benzodiazepines has been identified as potential antiarrhythmic agents that interact with sodium and potassium channels and prolong the ventricular effective refractory period (ERP) in anesthetized guinea pigs. Concomitant displacement of radiolabeled bactrachotoxin from site II in Na+ channels and of radiolabeled dofetilide from delayed rectifier K+ channels was evident with all members of this chemical series at a concentration of 10 microM. Structure-activity relationship (SAR) studies using a paced guinea pig model to assess prolongation of the ERP indicated that methyl or ethyl at the 1-position had little effect on activity, while larger groups caused a diminution of activity. Compounds with substituents at either the 3- or 4-position that increased lipophilicity generally were more potent; however, too many lipophilic substituents simultaneously at positions 1, 3, and 4 resulted in less active compounds. Substituents on either aromatic ring had little influence on activity, and phenyl at the 5-position resulted in a significant reduction in antiarrhythmic activity. When two sets of enantiomerically pure compounds were tested in the guinea pig, chirality was shown to be important for activity of 8, where the (R)-enantiomer was the more active, but not in the case of 15, where the enantiomers were equiactive. Several compounds in this series increased the threshold for ventricular fibrillation and refractoriness in myocardially-infarcted anesthetized cata and delayed the onset of aconitine-induced arrhythmias in anesthetized guinea pigs following intravenous dosing. Moreover, these compounds possessed oral antiarrhythmic activity in conscious myocardially-infarcted dogs. Compound R-15 has been advanced for further biological and toxicological evaluations.

Animals↗
PubMed1993

An evaluation of surveillance for Chlamydia trachomatis infections in the United States, 1987-1991.

PROBLEM/CONDITION: Chlamydia is the most common sexually transmitted bacterial pathogen in the United States; however, no precise data on the prevalence and incidence of chlamydia infection are available because currently no comprehensive national surveillance system exists for chlamydia. Despite the absence of such a system, states do report numbers of male and female chlamydia cases to CDC on a quarterly basis. REPORTING PERIOD COVERED: This report summarizes and reviews the chlamydia surveillance data received by CDC from 1987 through 1991. DESCRIPTION OF SYSTEM: Summary data on cases of chlamydia reported to state health departments were sent quarterly to CDC in Atlanta, Georgia. The quarterly data from each state included total number of chlamydia cases by sex and by source of report (public, private). RESULTS: From 1987 through 1991, the number of states with legislation mandating reporting of chlamydia increased twofold. The reported chlamydia rate from those states also doubled during the same time period, from 91.4 cases per 100,000 population in 1987 to 197.5 cases per 100,000 population in 1991. INTERPRETATION: This twofold increase in the rate of chlamydia reported to CDC did not represent a doubling in chlamydia prevalence or incidence during this time period. Instead, the increase resulted from the increase in the number of states with reporting laws and from the initial attempts of those states to identify and report diagnosed chlamydia infections. ACTIONS TAKEN: More accurate measures of the number of chlamydia infections and of trends in the chlamydia infection rate are needed to justify, develop, and evaluate public health programs to control chlamydia infections. An outline of possible surveillance activities for local communities is presented.

Chlamydia Infections↗
PubMed1993

Single-dose pharmacodynamics of diazepam and pentobarbital in substance abusers.

The likelihood that a given drug will be misused is related to its ability to alter mood, feeling, thinking, and perception in a manner that is liked by substance abusers. The subjective and behavioral effects of diazepam (10, 20, and 40 mg), pentobarbital (120 and 240 mg as a positive control), and placebo (negative control), were evaluated in 12 subjects with histories of substance abuse by use of a double-blind, Latin square crossover study design. Drug administration was separated by a minimum of 3 days. Pharmacodynamic measures included subjective (euphoria, subject liking, sedation, and symptoms) and behavioral (signs and observed liking) responses. The time course and profile of subjective and behavioral responses were similar for diazepam and pentobarbital. Valid relative potency estimates for the pharmacodynamic measures indicated that diazepam is approximately 10 times as potent as pentobarbital. The study indicates that the reinforcing effects of diazepam are similar to pentobarbital in substance abusers.

Adult↗
PubMed1993

Subjective and physiologic effects of intravenous buprenorphine in humans.

The pharmacologic profile of sublingual and subcutaneous buprenorphine, a partial opioid agonist, indicates it may be useful as a maintenance drug in the treatment of opioid dependence. However, illicit intravenous self-administration suggests that it may have a greater abuse potential by this route of administration. Physiologic and subjective effects of intravenous buprenorphine (0.0, 0.3, 0.6, and 1.2 mg) were determined in a dose-escalation study in six nondependent volunteers with histories of opioid use. Buprenorphine caused miosis and decreased respiratory rate, increased diastolic blood pressure, and transiently increased heart rate. Buprenorphine increased positive responses on a "feel drug" question and scores on scales of "liking," "good effects," euphoria, and apathetic sedation. Physiologic and subjective responses were not consistently dose related, a finding compatible with the pharmacologic profile of a partial agonist. The findings indicate that buprenorphine has substantial potential for abuse when administered intravenously.

Adult↗
PubMed1993

Antipsychotic drug exposure in a health maintenance organization.

In this study, exposure to antipsychotic drugs among ambulatory health maintenance organization (HMO) members is described. The diagnoses and mental health utilization associated with their use are explored, and concomitant drug use is investigated. The antipsychotic prescriptions were retrieved from an automated outpatient pharmacy data base for 2 years. Diagnoses for a two-percent sample of users were retrieved from an automated outpatient utilization data base. During the 2 years, 1,959 HMO members received 10,361 prescriptions for antipsychotics. Fifty-eight percent were female, and the mean age of users was 62 years of age. Haloperidol and thioridazine were the most frequently received drugs. Mean annual exposure to antipsychotics was 0.43% of the HMO population; estimated duration of exposure was 170 days; and estimated mean daily dose was 176 mg of chlorpromazine equivalents. Duration of exposure and mean daily dose were directly related. Both were also related to sex and age of users. Antipsychotic users were more likely to be exposed to various therapeutic classes of drugs indicative of chronic diseases. Antipsychotic exposure among ambulatory HMO members appeared to be conservative in terms of prevalence and similar to national experience in terms of daily dose. Estimated days of exposure appeared to place some users at increased risk of developing tardive dyskinesia, and the frequent and varied concomitant drug exposures can complicate treatment.

Adolescent↗