Minimal Clinically Important Difference in the 6-minute-walk Distance for Patients with Pulmonary Arterial Hypertension

Rationale: The 6-minute-walk distance (6MWD) is an important clinical and research metric in pulmonary arterial hypertension (PAH); however, there is no consensus about what minimal change in 6MWD is clinically significant. Objectives: We aimed to determine the minimal clinically important difference in the 6MWD. Methods: We performed a meta-analysis using individual participant data from eight randomized clinical trials of therapy for PAH submitted to the U.S. Food and Drug Administration to derive minimal clinically important differences in the 6MWD. The estimates were externally validated using the Pulmonary Hypertension Association Registry. We anchored the change in 6MWD to the change in the Medical Outcomes Survey Short Form physical component score. Measurements and Main Results: The derivation (clinical trial) and validation (Pulmonary Hypertension Association Registry) samples were comprised of 2,404 and 537 adult patients with PAH, respectively. The mean ± standard deviation age of the derivation sample was 50.5 ± 15.2 years, and 1,849 (77%) were female, similar to the validation sample. The minimal clinically important difference in the derivation sample was 33 meters (95% confidence interval, 27-38), which was almost identical to that in the validation sample (36 m [95% confidence interval, 29-43]). The minimal clinically important difference did not differ by age, sex, race, pulmonary hypertension etiology, body mass index, use of background therapy, or World Health Organization functional class. Conclusions: We estimated a 6MWD minimal clinically important difference of approximately 33 meters for adults with PAH. Our findings can be applied to the design of clinical trials of therapies for PAH.

The human bitter taste receptor TAS2R7 facilitates the detection of bitter salts

The human sense of taste is devoted to the analysis of the chemical composition of food prior to ingestion. Among the five basic taste qualities bitter taste perception is believed to avoid ingestion of potentially toxic substances. The receptors facilitating the detection of hundreds of chemically different bitter compounds belong to the taste 2 receptor (TAS2R) family, which are part of the G protein-coupled superfamily. Although the chemical classes of bitter compounds that have been identified as agonists of one of the 25 potentially functional human bitter taste receptors cover an enormous chemical space, one distinct group of bitter compounds, the bitter salts have not been assigned to any bitter taste receptor. To close this gap, we screened the entire human bitter taste receptor repertoire by functional calcium mobilization assays with the most famous bitter salt, magnesium sulfate, also known as Epsom salt. Although the profound pharmacological activity and the bitter taste of spring water containing magnesium sulfate has been known since 1697, the molecular basis for its taste has not been elucidated until now. Our screening resulted in the identification of a single receptor, the TAS2R7, responding to magnesium sulfate at concentrations humans perceive this salt as bitter. Subsequently, TAS2R7 was stimulated with other salts and it was found that this receptor also responds to manganese²⁺ and iron²⁺ ions, but not to potassium ions. Magnesium sulfate is known to exert a number of beneficial effects on the human body and thus, has been used as medicine against premature uterine contractions, as anti-arrhythmic drug and as laxative, however, magnesium sulfate overdosage can result in cardiac arrest and thus have fatal consequences. Therefore, it appears reasonable that nature placed TAS2R7 as sentinel for high concentrations of bitter salts on our tongues.

A force-based protein biochip

A parallel assay for the quantification of single-molecule binding forces was developed based on differential unbinding force measurements where ligand-receptor interactions are compared with the unzipping forces of DNA hybrids. Using the DNA zippers as molecular force sensors, the efficient discrimination between specific and nonspecific interactions was demonstrated for small molecules binding to specific receptors, as well as for protein-protein interactions on protein arrays. Finally, an antibody sandwich assay with different capture antibodies on one chip surface and with the detection antibodies linked to a congruent surface via the DNA zippers was used to capture and quantify a recombinant hepatitis C antigen from solution. In this case, the DNA zippers enable not only discrimination between specific and nonspecific binding, but also allow for the local application of detection antibodies, thereby eliminating false-positive results caused by cross-reactive antibodies and nonspecific binding.

Physicians' voices on physician-assisted suicide: looking beyond the numbers

Most empirical research examining physician views on physician-assisted suicide (PAS) has used quantitative methods to characterize positions and identify predictors of individual attitudes. This approach has generated limited information about the nature and depth of sentiments among physicians most impassioned about PAS. This study reports qualitative data provided by 909 physicians as part of a larger survey (N = 2,805) regarding attitudes toward and experiences with PAS and palliative care. Emergent themes illustrate important clinical, social, and ethical considerations in this area. The data illustrate the diverse and ardent responses that PAS evokes among certain physicians. The role of physicians' personal values is central to discussions about legalization of PAS. Polarized views such as those expressed by physicians in this study are not likely to be reconciled, thereby constraining the development of public policy regarding PAS.

Instability of attitudes about euthanasia and physician assisted suicide in depressed older hospitalized patients

The objective of this study was to examine the interest of non-terminally ill hospitalized elderly patients in euthanasia and physician assisted suicide (PAS) and to determine the stability of these interests over time. Patients age 60 or older (n=158), including both a depressed sample and non-depressed control sample, underwent a structured interview evaluating their interest in euthanasia and PAS in the event of a series of hypothetical outcome scenarios. Substantial proportions of subjects (varying from 13.3%-42% depending on the scenario) expressed hypothetical acceptance of euthanasia and PAS. After six months a subset of patients changed their minds about euthanasia and PAS (8% - 26% depending on the scenario), most often in the direction of initial acceptance to later rejection. Patients depressed in the hospital and interested in PAS for the outcome of their current (non-terminal) condition were significantly more likely express unstable opinions, with most rejecting it six months later. Other correlations of instability, in specific scenarios, included being male, experiencing higher baseline suffering, poorer subjective health and lower instrumental support. Because euthanasia and PAS actions are irreversible, findings of instability have important implications both clinically and for design of PAS legislation.

Life-sustaining treatment and assisted death choices in depressed older patients

OBJECTIVES

The major purpose of this study was to examine the effect of depressed mood in older, medically ill, hospitalized patients on their preferences regarding life-sustaining treatments, physician-assisted suicide (PAS), and euthanasia and to determine the degree to which financial constraints affected their choices.

DESIGN

Cross-sectional study.

SETTING

General medical hospital.

PARTICIPANTS

One hundred fifty-eight medically hospitalized, nondemented patients age 60 or older, mean age 74.1 (range 60-94). The sample was divided, based on Center for Epidemiologic Studies-Depression (CES-D) scores, into a depressed group (n = 71) and a nondepressed control group.

MEASUREMENTS

Subjects underwent a structured interview evaluating their life-sustaining treatment choices and whether they would accept or refuse PAS or euthanasia under a variety of hypothetical conditions. These choices were reevaluated with the introduction of financial impact. In addition, assessment included measures of depression, suicide, cognition, social support, functioning, and religiosity.

RESULTS

Depression was found to be highly associated with acceptance of PAS and euthanasia in most hypothetical clinical scenarios in addition to patients' current condition. Compared with nondepressed people, depressed respondents were 13 times as likely to accept PAS when considering their current condition (95% confidence interval [CI] 1.68-110.98), and over twice as likely to accept PAS when facing a hypothetical terminal illness or coma. Depression alone was weakly associated with life-sustaining treatment choices but, when financial impact was introduced, significantly more depressed subjects refused treatment options they had previously desired than did nondepressed subjects. The presence of suicidal ideation, even passive ideation, was strongly predictive of life-sustaining treatment refusals and increased interest in PAS and euthanasia. Depression's effect on acceptance of PAS was confirmed by logistic regression, which also showed that religious coping was significantly correlated with less interest in PAS in two hypothetical scenarios. CONCLUSION. Depressed subjects and even subjects with subtle, passive suicidal ideation were markedly more interested in PAS and euthanasia than nondepressed subjects in hypothetical situations. Depressed subjects were also particularly vulnerable to rejecting treatments if financial consequences might have resulted.

[Community health documentation as an instrument for further developing recommendations in community health]

The local health conference in a North Rhine-Westphalian county of Germany has made proposals to improve immunisation rates against measles, mumps and rubella. Another target was to prevent decubitus by elderly patients in hospitals, nursing homes and in the outpatient nursing. Local public health reports were the basis for the development of (local) health targets in the health conference. The data of 12,830 immunisation papers from 11-19-year old students showed immunisation rates against measles, mumps and rubella from 44% to 14% depending on the type of school. Virus hepatitis B immunisation rates are 32% in the county. There were also great differences between local towns of the county. The decubitus data showed rates from 2.3% in nursing homes to 5.1% in the outpatient sector. It is also shown that health reports and health conferences help to improve local conditions in public and individual health.

Physician-assisted suicide in Connecticut: physicians' attitudes and experiences

OBJECTIVE

This study examined aspects of physician attitudes toward physician-assisted suicide (PAS) not fully examined to date: evaluation of risks related to PAS, particularly the presence of depression, and the influence of religious and professionally-based values.

DESIGN

Anonymous, self-administered mailed questionnaire using Dillman methodology.

PARTICIPANTS

Targeted sample of physicians licensed by the Connecticut Department of Public Health in 1997 (n = 2,805 completed surveys; 40% response rate). DATA INCLUDE: Physician and patient characteristics, attitudes toward physician assisted suicide, and confidence in treating depression.

RESULTS

Religious affiliation, religiosity, ethnicity and medical specialty were strongly associated with views on PAS. Seven percent of respondents had been asked to write a lethal prescription during the past year, 15% of whom (n = 24) had complied with at least one request.

CONCLUSIONS

Most respondents expressed concern regarding certain risks associated with PAS, including movement toward involuntary euthanasia and the influence of undetected depression. Findings raise practical issues to be addressed through statutory or professional safeguards if PAS were to be legalized.

Schizophrenia and older adults. An overview: directions for research and policy

The Group for the Advancement of Psychiatry, Committee on Aging, believes that a crisis has emerged with respect to the understanding of the nature and treatment of schizophrenia in older persons. Moreover, critical gaps exist in clinical services for this population. In this article, we examine the epidemiology of aging and schizophrenia; life-course changes in psychopathology, cognitive function, social functioning, and physical health; and various concerns regarding treatment, services, and financing. Finally, we propose six research and policy recommendations and suggest methods for addressing the research questions that we have posed.

The physician-assisted suicide policy dilemma: a pilot study of the views and experiences of Connecticut physicians

Development of fully informed public policy regarding physician-assisted suicide (PAS) requires a thorough understanding of the experiences, attitudes, and beliefs of physicians with respect to this issue. This study gathered data on physician characteristics, attitudes toward PAS, factors influencing attitudes toward PAS, and sensitivity to the role of depression in a sample of 397 psychiatrists, internists, and family practitioners in Connecticut. Central considerations included: the influence of religious values, professional discipline and practice patterns, and ability to diagnose depression in a single evaluation. Psychiatrists were significantly more likely to be supportive of PAS than were internists or family practitioners. Most respondents expressed concern regarding the influence of depression on PAS requests. A subset of physicians endorse PAS yet do not share such concern about risks, suggesting substantial challenges for policy-makers.

Biochemical outcome after radical prostatectomy, external beam radiation therapy, or interstitial radiation therapy for clinically localized prostate cancer

CONTEXT

Interstitial radiation (implant) therapy is used to treat clinically localized adenocarcinoma of the prostate, but how it compares with other treatments is not known.

OBJECTIVE

To estimate control of prostate-specific antigen (PSA) after radical prostatectomy (RP), external beam radiation (RT), or implant with or without neoadjuvant androgen deprivation therapy in patients with clinically localized prostate cancer.

DESIGN

Retrospective cohort study of outcome data compared using Cox regression multivariable analyses.

SETTING AND PATIENTS

A total of 1872 men treated between January 1989 and October 1997 with an RP (n = 888) or implant with or without neoadjuvant androgen deprivation therapy (n = 218) at the Hospital of the University of Pennsylvania, Philadelphia, or RT (n = 766) at the Joint Center for Radiation Therapy, Boston, Mass, were enrolled.

MAIN OUTCOME MEASURE

Actuarial freedom from PSA failure (defined as PSA outcome).

RESULTS

The relative risk (RR) of PSA failure in low-risk patients (stage T1c, T2a and PSA level < or =10 ng/mL and Gleason score < or =6) treated using RT, implant plus androgen deprivation therapy, or implant therapy was 1.1 (95% confidence interval [CI], 0.5-2.7), 0.5 (95% CI, 0.1-1.9), and 1.1 (95% CI, 0.3-3.6), respectively, compared with those patients treated with RP. The RRs of PSA failure in the intermediate-risk patients (stage T2b or Gleason score of 7 or PSA level >10 and < or =20 ng/mL) and high-risk patients (stage T2c or PSA level >20 ng/mL or Gleason score > or =8) treated with implant compared with RP were 3.1 (95% CI, 1.5-6.1) and 3.0 (95% CI, 1.8-5.0), respectively. The addition of androgen deprivation to implant therapy did not improve PSA outcome in high-risk patients but resulted in a PSA outcome that was not statistically different compared with the results obtained using RP or RT in intermediate-risk patients. These results were unchanged when patients were stratified using the traditional rankings of biopsy Gleason scores of 2 through 4 vs 5 through 6 vs 7 vs 8 through 10.

CONCLUSIONS

Low-risk patients had estimates of 5-year PSA outcome after treatment with RP, RT, or implant with or without neoadjuvant androgen deprivation that were not statistically different, whereas intermediate- and high-risk patients treated with RP or RT did better then those treated by implant. Prospective randomized trials are needed to verify these findings.

[Vaccination status and implementation of recommendations for vaccination with special reference to measles-mumps-rubella vaccination. 1995 program for school entrance]

Children who took part in the medical examination for elementary school starters and who could present a certificate of vaccination were given a written vaccination recommendation. On the first day of school the recommendation sheets filled out by the family doctor or a paediatrician were collected and analysed anonymously. 2194 of 2965 children received a vaccination recommendation. 1047 sheets could be interpreted. Based on the current recommendation of the STIKO (German official vaccination council) a MMR (measles, mumps, rubella) vaccination was suggested in 1001 cases. Only 53.1% of the proposed vaccinations have been given, despite consultation with the family doctor or paediatrician.

Cyclin B1 availability is a rate-limiting component of the radiation-induced G2 delay in HeLa cells

Irradiation of tumor cells results in a G2 delay, which has been postulated to allow DNA repair and cell survival. The G2 delay after irradiation is marked in HeLa and other cells by delayed expression of cyclin B1. To test whether this depression of cyclin B1 contributes to the G2 delay, we induced cyclin B1 expression in irradiated HeLa cells using a dexamethasone-inducible promoter. Induction of cyclin B1 after radiation abrogated the G2 delay by approximately doubling the rate at which the cells reentered mitosis, whereas dexamethasone itself had no effect. However, overexpression of cyclin B1 did not eliminate the G2 delay in irradiated cells. In unirradiated cells, overexpression of cyclin B1 had no effect on cell cycle progression. Confirmation that reduction of cyclin B1 levels would prolong G2 was provided using antisense oligonucleotides to cyclin B1. These results demonstrate that cyclin B1 levels control the length of the G2 delay following irradiation in HeLa cells but do not exclude additional mechanisms controlling the mitotic delay after irradiation.

Murine leukemia virus infects early bone marrow progenitors in immunocompetent mice

Chronic murine leukemia viruses (MuLVs) are retroviruses which induce leukemias/lymphomas after long latency periods. The induction of leukemia by MuLVs is complex, requiring multiple steps beginning with infection of an appropriate target cell. A number of investigators have proposed a bone marrow-thymus axis in the development of retrovirus induced T-cell lymphoma in which cells are initially infected in the bone marrow. These bone marrow cells or their progeny migrate to the thymus during the disease process. In our system using adult, immunocompetent BALB.K mice infected with E-55(+) MuLV, a similar pattern is seen; integrated virus is initially detectable in the bone marrow and spleen and only later in the thymus. In order to better understand the leukemic process, we analyzed the bone marrow from adult, immunocompetent BALB.K mice infected with the E-55(+) MuLV in bone marrow colony assays. The results from these assays demonstrate that either a pluripotent progenitor cell or an early progenitor cell is a target in the bone marrow for the virus.

Bringing clinical accuracy to provider profiling systems

Traditional provider profiling systems have difficulty accounting for the wide-ranging differences between patients, their conditions, and the physicians' practices. However, new technologies and methodologies that can extract the needed information from existing data sources offer a means of accurately and efficiently comparing the performance of providers, specialties, networks, and other elements of managed care organizations. Profiling can strengthen the bonds of trust between the providers and the managed care organization, making them partners in delivering quality care.

Mechanisms of caloric restriction affecting aging and disease

Caloric restriction (CR) appears to affect aging by the inhibition of the specific chronic diseases which occur at increasing frequency with age. A common disease in F-344 rats, granulocytic leukemia, appears to have a window where it is sensitive to the effects of CR. Other diseases, such as pituitary adenomas, appear to have a different relationship to growth in the animal. Additionally, a model for the major disease for a number of long-lived strains of mice, lymphoma, which CR effects by inhibiting the expression of the causative agent, is being developed. Evaluation of the effects of CR on neoplasia, degenerative disease and physiological parameters suggests that the major factors in expression of these diseases is the alteration of growth factors, hormonal status, etc., and that these alterations also affect strain-specific pathologies depending on when they are changed in the life span. Effecting different diseases at different times in the life span, long-term CR, by limiting exposure to endogenous growth factors, altering physiological characteristics, and limiting exposure to food toxicants, inhibits the onset of disease, and its sequela, aging.

Prospective study of tardive dyskinesia incidence in the elderly

OBJECTIVES

To investigate the incidence of tardive dyskinesia in elderly individuals beginning treatment with antipsychotic drugs and to identify risk factors for the development of tardive dyskinesia in the elderly.

DESIGN

A cohort of previously neuroleptic-naive patients was identified at the time of initiation of antipsychotic drug treatment. Patients were evaluated at baseline and followed up at 3-month intervals for periods ranging from 3 to 119 weeks.

SETTING

Subjects were recruited from the psychiatric and geriatric medical services of two medical centers, a geriatric institute, and three nursing homes in the metropolitan area of New York City, NY.

PATIENTS

Two hundred fifteen individuals older than 55 years have entered the study thus far. Preliminary data are presented for 160 patients who were followed up for at least 1 month. Their age range was 57 to 99 years (mean, 77 years). Seventy-two percent were women and 87% were white. Sixty-seven percent of patients had a diagnosis of organic mental syndrome and 42% had a psychiatric diagnosis.

INTERVENTIONS

A naturalistic, longitudinal, repeated assessment paradigm was employed. Assessments included abnormal involuntary movements, extrapyramidal signs, psychiatric symptoms, and medical and drug treatment histories.

MAIN OUTCOME MEASURE

The incidence of tardive dyskinesia was determined using a standardized rating instrument and survival analysis.

RESULTS

The incidence of neuroleptic-induced dyskinesia was 31% (95% confidence interval, 20%, 42%) after 43 weeks of cumulative neuroleptic treatment. Psychiatric (as opposed to organic) diagnosis and presence of extrapyramidal signs early in treatment were associated with increased tardive dyskinesia vulnerability.

Regulation of benzodiazepine prescribing practices: clinical implications

In an effort to control prescription abuse of benzodiazepines, the New York State Department of Health (DOH) enacted a regulation requiring the use of triplicate prescriptions for these medications. DOH predicted that this regulation would reduce the overall abuse of benzodiazepines and eliminate widescale organized fraud and abuse without any negative impact or reduced availability to patients. Following implementation of the regulation, the authors reviewed all psychiatric emergency room cases and outpatient clinic walk-in evaluations over a 3-month period in an urban medical center and identified 59 cases in which the use of benzodiazepines was a significant presenting problem. Of these, 24 (41%) were judged to be directly related to the new triplicate regulation. In all but one of these cases the patient presented because of symptoms or concerns directly stemming from the refusal by a clinician to continue prescribing a benzodiazepine in a previously established pattern. Typically, abrupt discontinuation of benzodiazepine treatment led to a withdrawal syndrome and/or the unmasking of a previously treated anxiety disorder. In attempting to redress what are essentially criminal substance abuse problems through the regulation of legitimate clinical practice, regulatory agencies may ultimately deprive patients of appropriate, legitimate, and efficacious treatments.

Psychiatric commitment of the elderly

Involuntary hospitalization of the elderly has been the focus of controversy. In many jurisdictions, commitment criteria are stringently and narrowly defined, require a showing of "dangerousness," and are difficult to apply toward securing proper treatment for the elderly. In other areas, broader criteria apply, but some authors argue that such criteria are inappropriately used with the elderly and leave them vulnerable to the abuse of unnecessary institutionalization. The authors examined 274 consecutive admissions aged 55 years and over, comparing voluntary and involuntary patients. Patients admitted involuntarily were significantly more likely to have organic mental disorders, be violent before admission, and be disoriented, withdrawn, and apathetic. Voluntary patients were significantly more likely to have major mood disorders. Patients who lived with others were more likely to be committed than those living alone. The authors discuss these findings with attention to the appropriateness of broader commitment standards and the more stringent dangerousness criteria as they apply to the geriatric population.

Shifting competency during hospitalization: a model for informed consent decisions

The demonstration of factual understanding should be sought when determining a patient's ability to give informed consent, but a patient's failure to demonstrate understanding should not always be equated with an inability to competently consent to or refuse treatment. The authors demonstrate the clinical use of a number of standards other than factual understanding. Judgments about competency are derived both from the patient's clinical condition and the risks and benefits inherent in the decision the patient is asked to make. Since both of these conditions may shift during the course of treatment, clinical competency is subject to continual reassessment using a variety of competency standards. The authors demonstrate the use of their model of shifting competency at five junctures in the treatment of a delusional patient.

Relationship of psychological processes during delirium to outcome

To determine which psychological processes during delirium might correlate with and predict postdelirium psychological outcome, the authors prospectively studied 34 burn patients who became delirious during hospitalization. After the delirium resolved, seven of the 25 survivors had severe psychological symptoms--either depression or posttraumatic stress disorders. During delirium, this outcome group was clinically distinctive: They showed significantly more preoccupation with their trauma and injury, had greater anxiety and fear, and differed in their use of defensive operations. These findings suggest modifying the standard approach to the delirious patient.

Medical students' learning as primary therapists or as participant/observers in a psychiatric clerkship

The authors assessed two different inpatient models of clinical clerkships in psychiatry on the basis of both an examination assessing amount of learning and a survey of student attitudes. One clerkship model placed the third-year medical student in the role of primary therapist; the other model assigned each student to join a psychiatrist as a participant/observer. No overall difference in objective assessment of learning was found between the two groups of students, and student attitudes generally favored the participant/observer model. These findings suggest that the widespread bias favoring the primary therapist model may not be justified.

[Evaluation of Berlin jacket crowns compared with plastic or ceramic jacket crowns]

34 jacket crowns of ceramic material, of plastic and of a combination plastic-ceramic material (Berlin jacket crowns), respectively, were clinically re-examined using a uniform scoring scale. The results obtained show that the Berlin jacket crowns can be ranked between the ceramic jacket crowns and the plastic jacket crowns.

Monocular spatial distortions induced by marked accommodation

Contraction of the ciliary muscle during marked accommodation causes the leading edge of the retina to advance as much as 0.5 centimeter. Near the posterior pole of the eye, the upward and downward extensional strains on the retina should be reasonably balanced. In the horizontal meridian an asymmetry is introduced because of the nasal location of the optic nerve head. Observers were asked to bisect the space between two parallel lines while fixating a movable line lying near the midpoint of the two lines. The test was conducted with the target far from and near the subject, in the horizontal and vertical meridians, and was repeated with accommodation paralyzed by a cycloplegic agent. Marked accommodation induced significant spatial distortions in the horizontal meridian. The effect is largely retinal.