Activin type I receptor polymorphisms and body composition in older individuals with sarcopenia-Analyses from the LACE randomised controlled trial

BACKGROUND

Ageing is associated with changes in body composition including an overall reduction in muscle mass and a proportionate increase in fat mass. Sarcopenia is characterised by losses in both muscle mass and strength. Body composition and muscle strength are at least in part genetically determined, consequently polymorphisms in pathways important in muscle biology (e.g., the activin/myostatin signalling pathway) are hypothesised to contribute to the development of sarcopenia.

METHODS

We compared regional body composition measured by DXA with genotypes for two polymorphisms (rs10783486, minor allele frequency (MAF) = 0.26 and rs2854464, MAF = 0.26) in the activin 1B receptor (ACVR1B) determined by PCR in a cross-sectional analysis of DNA from 110 older individuals with sarcopenia from the LACE trial.

RESULTS

Neither muscle mass nor strength showed any significant associations with either genotype in this cohort. Initial analysis of rs10783486 showed that males with the AA/AG genotype were taller than GG males (174±7cm vs 170±5cm, p = 0.023) and had higher arm fat mass, (median higher by 15%, p = 0.008), and leg fat mass (median higher by 14%, p = 0.042). After correcting for height, arm fat mass remained significantly higher (median higher by 4% padj = 0.024). No associations (adjusted or unadjusted) were seen in females. Similar analysis of the rs2854464 allele showed a similar pattern with the presence of the minor allele (GG/AG) being associated with greater height (GG/AG = 174±7 cm vs AA = 170 ±5cm, p = 0.017) and greater arm fat mass (median higher by 16%, p = 0.023). Again, the difference in arm fat remained after correction for height. No similar associations were seen in females analysed alone.

CONCLUSION

These data suggest that polymorphic variation in the ACVR1B locus could be associated with body composition in older males. The activin/myostatin pathway might offer a novel potential target to prevent fat accumulation in older individuals.

ACE I/D genotype associates with strength in sarcopenic men but not with response to ACE inhibitor therapy in older adults with sarcopenia: Results from the LACE trial

BACKGROUND

Angiotensin II (AII), has been suggested to promote muscle loss. Reducing AII synthesis, by inhibiting angiotensin converting enzyme (ACE) activity has been proposed as a method to inhibit muscle loss. The LACE clinical trial was designed to determine whether ACE inhibition would reduce further muscle loss in individuals with sarcopenia but suffered from low recruitment and returned a negative result. Polymorphic variation in the ACE promoter (I/D alleles) has been associated with differences in ACE activity and muscle physiology in a range of clinical conditions. This aim of this analysis was to determine whether I/D polymorphic variation is associated with muscle mass, strength, in sarcopenia or contributed to the lack of response to treatment in the LACE study.

METHODS

Sarcopenic individuals were recruited into a 2x2 factorial multicentre double-blind study of the effects of perindopril and/or leucine versus placebo on physical performance and muscle mass. DNA extracted from blood samples (n = 130 72 women and 58 men) was genotyped by PCR for the ACE I/D polymorphism. Genotypes were then compared with body composition measured by DXA, hand grip and quadriceps strength before and after 12 months' treatment with leucine and/or perindopril in a cross-sectional analysis of the influence of genotype on these variables.

RESULTS

Allele frequencies for the normal UK population were extracted from 13 previous studies (I = 0.473, D = 0.527). In the LACE cohort the D allele was over-represented (I = 0.412, D = 0.588, p = 0.046). This over-representation was present in men (I = 0.353, D = 0.647, p = 0.010) but not women (I = 0.458, D = 0.532, p = 0.708). In men but not women, individuals with the I allele had greater leg strength (II/ID = 18.00 kg (14.50, 21.60) vs DD = 13.20 kg (10.50, 15.90), p = 0.028). Over the 12 months individuals with the DD genotype increased in quadriceps strength but those with the II or ID genotype did not. Perindopril did not increase muscle strength or mass in any polymorphism group relative to placebo.

CONCLUSION

Our results suggest that although ACE genotype was not associated with response to ACE inhibitor therapy in the LACE trial population, sarcopenic men with the ACE DD genotype may be weaker than those with the ACE I/D or II genotype.

Effect of perindopril or leucine on physical performance in older people with sarcopenia: the LACE randomized controlled trial

BACKGROUND

This trial aimed to determine the efficacy of leucine and/or perindopril in improving physical function in older people with sarcopenia.

METHODS

Placebo-controlled, parallel group, double-blind, randomized two-by-two factorial trial. We recruited adults aged ≥ 70 years with sarcopenia, defined as low gait speed (<0.8 m/s on 4 m walk) and/or low handgrip strength (women < 20 kg, men < 30 kg) plus low muscle mass (using sex and body mass index category-specific thresholds derived from normative UK BioBank data) from 14 UK centres. Eligible participants were randomized to perindopril 4 mg or placebo, and to oral leucine powder 2.5 g or placebo thrice daily. The primary outcome was the between-group difference in the short physical performance battery (SPPB) score over 12-month follow-up by repeated-measures mixed models. Results were combined with existing systematic reviews using random-effects meta-analysis to derive summary estimates of treatment efficacy.

RESULTS

We screened 320 people and randomized 145 participants compared with an original target of 440 participants. For perindopril [n = 73, mean age 79 (SD 6), female sex 39 (53%), mean SPPB 7.1 (SD 2.3)] versus no perindopril [n = 72, mean age 79 (SD 6), female sex 39 (54%), mean SPPB 6.9 (SD 2.4)], median adherence to perindopril was lower (76% vs. 96%; P < 0.001). Perindopril did not improve the primary outcome [adjusted treatment effect -0.1 points (95%CI -1.2 to 1.0), P = 0.89]. No significant treatment benefit was seen for any secondary outcome including muscle mass [adjusted treatment effect -0.4 kg (95%CI -1.1 to 0.3), P = 0.27]. More adverse events occurred in the perindopril group (218 vs. 165), but falls rates were similar. For leucine [n = 72, mean age 78 (SD 6), female sex 38 (53%), mean SPPB 7.0 (SD 2.1)] versus no leucine [n = 72, mean age 79 (SD 6), female sex 40 (55%), mean SPPB 7.0 (SD 2.5)], median adherence was the same in both groups (76% vs. 76%; P = 0.99). Leucine did not improve the primary outcome [adjusted treatment effect 0.1 point (95%CI -1.0 to 1.1), P = 0.90]. No significant treatment benefit was seen for any secondary outcome including muscle mass [adjusted treatment effect -0.3 kg (95%CI -1.0 to 0.4), P = 0.47]. Meta-analysis of angiotensin converting enzyme inhibitor/angiotensin receptor blocker trials showed no clinically important treatment effect for the SPPB [between-group difference -0.1 points (95%CI -0.4 to 0.2)].

CONCLUSIONS

Neither perindopril nor leucine improved physical performance or muscle mass in this trial; meta-analysis did not find evidence of efficacy of either ACE inhibitors or leucine as treatments to improve physical performance.

Acceptability and feasibility of magnetic femoral nerve stimulation in older, functionally impaired patients

Objective

Magnetic femoral nerve stimulation to test muscle function has been largely unexplored in older people. We assessed acceptability, feasibility, along with reproducibility and correlation with other physical function measures.

Results

Study 1 recruited older people with sarcopenia. Stimulation was performed at baseline and 2 weeks along with six minute walk (6MW), maximum voluntary quadriceps contraction, short physical performance battery and grip strength. Acceptability was measured using visual analog scales. Study 2 used baseline data from a trial of older people. We correlated stimulation results with 6MW, maximal voluntary contraction and muscle mass. Maximum quadriceps twitch tension was measured in both studies, evoked using biphasic magnetic stimulation of the femoral nerve. In study 1 (n = 12), magnetic stimulation was well tolerated with mean discomfort rating of 9% (range 0–40%) on a visual analog scale. Reproducibility was poor (intraclass correlation coefficient 0.06; p = 0.44). Study 2 (n = 64) showed only weak to moderate correlations for maximum quadriceps twitch tension with other measures of physical function (6 minute walk test r = 0.24, p = 0.06; maximal voluntary contraction r = 0.26; p = 0.04). We conclude that magnetic femoral nerve stimulation is acceptable and feasible but poorly reproducible in older, functionally impaired people.

Hospital-acquired pneumonia incidence and diagnosis in older patients

BACKGROUND

hospital-acquired pneumonia poses a hazard to older people who are hospitalised, yet few data exist on the incidence or risk factors in non-intensive care patients. This study aimed to determine the incidence of hospital-acquired pneumonia (HAP) in a sample of hospitalised older people.

METHODS

prospective survey of hospitalised older patients (>65 years) at a single centre over a 12-month period. Casenote and chart data were collected on acute medical, orthopaedic and Medicine for the Elderly wards. HAP was defined in accordance with the European and Scottish National Prevalence Survey 2011 definition. Key analyses were incidence of clinically suspected and case definition clinically confirmed HAP.

RESULTS

one thousand three hundred and two patients were included in the analysis. Five hundred and thirty-nine (41%) were male; mean age was 82 years (SD 8). Median length of hospital stay was 14 days (IQR 20). One hundred and fifty-seven episodes of HAP were clinically suspected in 143 patients (10.9% of admissions), but only 83 episodes in 76 patients met the diagnostic criteria (5.8% of admissions). The risk of HAP was 0.3% per day in hospital. Reasons for failure to meet the diagnostic criteria in 75 cases were lack of radiographic evidence in 60/75; lack of evidence of inflammation in 42/75, and lack of respiratory signs or symptoms in 13/75; 35/75 (47%) of cases lacked evidence in two or more domains.

CONCLUSION

HAP is common but over-diagnosed in older hospitalised patients.

Effect of spironolactone on physical performance in older people with self-reported physical disability

BACKGROUND

Interventions that improve muscle function may slow decline in physical function and disability in later life. Recent evidence suggests that inhibition of the renin-angiotensin-aldosterone system may maintain muscle function. We evaluated the effect of aldosterone blockade on physical performance in functionally impaired older people without heart failure.

METHODS

In this parallel-group, double-blind, randomized, placebo-controlled trial, community-dwelling participants aged ≥65 years with self-reported problems with activities of daily living were randomized to receive 25 mg spironolactone or identical placebo daily for 20 weeks. The primary outcome was change in 6-minute walking distance over 20 weeks. Secondary outcomes were changes in Timed Up and Go test, Incremental Shuttle Walk Test, Functional Limitation Profile, EuroQol EQ-5D, and Hospital Anxiety and Depression Scale over 20 weeks.

RESULTS

Participants' mean (standard deviation) age was 75 (6) years. Of the 93% of participants (112/120) who completed the study, 106 remained on medication at 20 weeks. There was no significant difference in change in 6-minute walking distance at 20 weeks between the spironolactone and placebo groups (mean change, -3.2 m; 95% confidence interval, -28.9 to 22.5; P = .81). Quality of life improved significantly at 20 weeks, with an increase in EuroQol EQ-5D score of 0.10 (95% confidence interval, 0.03-0.18; P < .01) in the spironolactone group relative to the placebo group. There were no significant differences in between-group change for other secondary outcomes.

CONCLUSIONS

Spironolactone was well tolerated but did not improve physical function in older people without heart failure. Quality of life improved significantly, and the possible mechanisms for this require further study.

Mineralocorticoid antagonism: a novel way to treat sarcopenia and physical impairment in older people?

Dysregulation of the renin-angiotensin-aldosterone system has been associated with a number of age-related pathologies including hypertension, heart failure and chronic kidney disease. More recently, it has been suggested that alterations within the RAAS may contribute to the development of sarcopenia and subsequent decline in physical function. There is growing interest in developing interventions to prevent age-associated decline in muscle function. We postulate that inhibition of the RAAS with the mineralocorticoid antagonist spironolactone may have a role in countering the effects of physical impairment in older people by improving skeletal muscle function. Spironolactone may prevent skeletal myocyte apoptosis, improve vascular endothelial function and enhance muscle contractility by increasing muscle magnesium and sodium-potassium pumps. This article will review the literature underpinning the hypothesis that spironolactone may have a role in maintaining muscle function in older people.

Optimal management of sarcopenia

Sarcopenia is the progressive generalized loss of skeletal muscle mass, strength, and function which occurs as a consequence of aging. With a growing older population, there has been great interest in developing approaches to counteract the effects of sarcopenia, and thereby reduce the age-related decline and disability. This paper reviews (1) the mechanisms of sarcopenia, (2) the diagnosis of sarcopenia, and (3) the potential interventions for sarcopenia. Multiple factors appear to be involved in the development of sarcopenia including the loss of muscle mass and muscle fibers, increased inflammation, altered hormonal levels, poor nutritional status, and altered renin-angiotensin system. The lack of diagnostic criteria to identify patients with sarcopenia hinders potential management options. To date, pharmacological interventions have shown limited efficacy in counteracting the effects of sarcopenia. Recent evidence has shown benefits with angiotensin-converting enzyme inhibitors; however, further randomized controlled trials are required. Resistance training remains the most effective intervention for sarcopenia; however, older people maybe unable or unwilling to embark on strenuous exercise training programs.

Spiritual care in the hospital: who requests it? Who needs it?

Reports the results of a survey of general medical and surgical patients (N=202) who were asked if they wanted to have a chaplain talk with them, have a chaplain pray with them, and/or receive the sacrament of communion. Discusses the implications of the findings for hospital chaplains.

When religion may be an ethical issue

Though Americans are a religious people, there are times when religion or religious views may confound the ethical process. This article claims that religious values may be expressed as either principles or narratives, then seeks to establish a case for dealing with religious claims as "principled narratives." Methods of evaluation are explored and then seven guidelines are offered for dealing with religion in ethics consultations.

The patient who could not be discharged. How far should patient autonomy extend?

A male patient was admitted to the acquired immune deficiency syndrome (AIDS) unit for hemodialysis. His history revealed that he was homeless and that he had tested positive for human immunodeficiency virus (HIV+). He also had a history of alcohol and intravenous drug abuse and tuberculosis. Based on the results of a chest X-ray, he was placed in respiratory isolation. During the next few days of his hospitalization, he exhibited nonadherent behavior toward the treatment regime. Because of previous verbal and physical abuse to staff and patients, all local hemodialysis centers refused to accept him as a patient. Thus, he became a patient who seemingly could never be discharged. A discussion related to the theoretical and practical scope of patient autonomy, institutional altruism vs. institutional self-interest, and the need for social policy to facilitate a just and humane resolution to this ethical situation is presented here.

Affective verbal memory in patients with temporal lobe epilepsy

Eighteen epileptic patients with unilateral temporal lobe epilepsy (9 left, 9 right) were evaluated with a verbal memory task involving recall of 2 stories, 1 with affective content and 1 that was neutral. A trend for better performance by the group with intact left hemispheres was found for a quantitative score of number of story units recalled. For a qualitative score of number of symbolic distortions, a main effect of affective load was found, such that more distortions were made for the story with affective than neutral content. This effect remained significant when the left temporal lobe epilepsy patients were analyzed separately and was not found for the right temporal lobe epilepsy patients alone. Additional analyses for the subset of 5 patients with left and 6 patients with right temporal lobectomies involving removal of the hippocampus and amygdala were in the same direction as the analyses for all 18 participants. These findings are consistent with other reports of material-specific memory deficits, such that verbal memory deficits are associated with left temporal lobe epilepsy. The differences between performance on the affective and neutral stories for the left and right temporal lobe epilepsy patients are discussed and related to the role of the amygdala in affective processing.

Emotional status after right vs. left temporal lobectomy

Nineteen temporal lobectomy patients with epilepsy were evaluated (11 right and 8 left) with a brief questionnaire that addressed: (1) General Happiness; (2) Depression; (3) Anxiety; (4) Impulse Control; and (5) Socialization. The patients with left temporal lobectomy reported increases in depression and decreases in socialization compared with the right temporal lobectomy patients after surgery. Furthermore although the right temporal lobectomy patients reported increases in general happiness, no changes in general happiness were reported by the left temporal lobectomy patients. The present study supported the idea that an increased negative affect is associated with left rather than right temporal lobectomy. This is consistent with a model of negative emotional valence when the right hemisphere dominates awareness.

Incidence of the Fuld WAIS-R profile in traumatic brain injury and Parkinson's disease

The frequency of occurrence of the Fuld Profile for cholinergic deficiency was investigated in two clinical populations: inpatients who had suffered traumatic brain injury and outpatients who carried a diagnosis of Parkinson's disease. The observed incidence of positive Fuld profiles was not significantly different in the two groups, 14% in the traumatic brain injury group and 24% in the Parkinson's disease group. These findings are consistent with recent reviews of the sensitivity and specificity of the Fuld profile in various clinical and nonclinical populations. The generally low sensitivity of the Fuld profile does not support its usefulness in the differential diagnosis of dementia. However, it may serve as an indicator of cholinergic deficiency, which could be used to select patients who would be likely to respond to cholinomimetic therapies.

The spiritual dimension of palliative care

OBJECTIVES

To review the relevant literature about spirituality and palliation in oncology and to suggest a model for framing and understanding the spiritual themes oncology patients may present.

DATA SOURCES

Research studies, review articles, and books related to spirituality, palliation, patient and staff preferences, family therapy, and culture.

CONCLUSIONS

Spirituality/religion is a significant element in the lives of most Americans and plays a role in coping with crisis events such as cancer. Responding to the spiritual dimension is an important part of palliative care.

IMPLICATIONS FOR NURSING PRACTICE

Caregivers must learn and use appropriate assessment protocols and include appropriate spiritual/religious interventions in careplans.

The continuum of deep/surface dyslexia

A right-handed male sustained traumatic brain injury which resulted in anomia, dyslexia and agraphia. The most severe CT (computed tomography)-identified brain damage was located in the right parieto-temporal lobe. In the first months following the injury, the pattern of reading errors was similar to that associated with deep dyslexia. However, nonlexical derivation of phonology from print was not abolished. As the patient's ability to associate letter patterns with sounds improved, oral reading also improved. Although he no longer produced semantic errors in oral reading, he continued to produce oral reading errors that were visually and phonologically related to the targets. Four months after the injury, the error pattern observed in the patient's oral reading was consistent with very mild surface dyslexia. The significance of these observations to dual-deficit models of acquired dyslexia is discussed, as are their implications for rehabilitation.

The religious needs and resources of psychiatric inpatients

A recent survey of psychiatric research indicates religion has been given little attention, and when it has been considered, the measures have been simplistic. The present study was designed to describe the religious needs and resources of psychiatric inpatients. With the use of a multidimensional conception of religion and two established instruments, 51 adult psychiatric inpatients were surveyed about their religious needs and resources. For comparison, 50 general medical/surgical patients, matched for age and gender, were also surveyed. Eighty-eight percent of the psychiatric patients reported three or more current religious needs. Although there were no differences in religious needs between the two patient groups, there were significant differences in religious resources. Psychiatric patients had lower spiritual well-being scores and were less likely to have talked with their clergy. Religion is important for the psychiatric patients, but they may need assistance to find resources to address their religious needs.

Effect of topiramate on attention

Impaired attention is a frequently reported side effect of anti-epileptic medication, as well as a frequent general complaint of epilepsy. It is thus important to evaluate the effect of new medications on attention processes. Attention was assessed weekly in ten subjects receiving topiramate over a 3 month period. Attention was evaluated with digit span, a widely used index of attention. Different number sequences were constructed and randomized to allow for repeated use. Four of nine subjects showed significant correlations between topiramate dosage and forward digit span measured weekly, such that higher dosage was associated with poorer attention. The average topiramate dosage and seizure reduction did not differ between these subjects and those who did not show a significant relationship.

Depression and the soul

Clergy are often confronted by challenges in dealing with the depressed congregant. This paper addresses the interface between psychology, psychiatry, and religion in a discussion of two cases. Models are suggested for dealing with the issues raised by the depressed congregant. The paper developed from a symposium on "The Depressed Congregant: Three Pastoral Responses to a Case Vignette" presented at a conference for cleargy onDepression and The Soul, at Temple Sholom in Chicago.

Effects of freezing, thawing, and storing human liver microsomes on cytochrome P450 activity

The stability of cytochrome P450 enzymes, cytochrome b5, and NADPH-cytochrome c reductase was examined in (A) human liver samples frozen in liquid nitrogen and stored at -80 degrees C, (B) human liver microsomes suspended in 250 mM sucrose and stored at -80 degrees C, and (C) human liver microsomes subjected to as many as 10 cycles of thawing and freezing. In study A, microsomes from five human livers were prepared from fresh (unfrozen) tissue and from tissue that was stored frozen at -80 degrees C for 1, 2, 4, or 6 months. The apparent concentration of cytochromes P450 and b5 and the activity of NADPH-cytochrome c reductase decreased 20-40% as a result of freezing the liver, regardless of whether the liver was stored for 1 or 6 months. Similar decreases were observed in the activities of cytochrome P450 enzymes belonging to several gene families, namely CYP1A2 (7-ethoxyresorufin O-dealkylation and caffeine N3-demethylation), CYP2A6 (coumarin 7-hydroxylation), CYP2C9 (tolbutamide methylhydroxylation), CYP2C19 (S-mephenytoin 4'- hydroxylation), CYP2D6 (dextromethorphan O-de-methylation), CYP2E1 (chlorzoxazone 6-hydroxylation), CYP3A4solidus5 (testosterone 6beta-hydroxylation), and CYP4A9solidus11 (lauric acid 12-hydroxylation). Freezing human liver did not convert cytochrome P450 to its inactive form, cytochrome P420, but it increased the contamination of liver microsomes with hemoglobin or other heme-containing proteins, which resulted in a uniform decrease in the specific activity of cytochromes P450 and b5 and in the specific activity of all P450 enzymes. In study B, the concentration of cytochromes P450 and b5, the activity of NADPH-cytochrome c reductase, and the activity of individual cytochrome P450 enzymes were determined in 10 samples of human liver microsomes stored at -80 degrees C for approximately 0, 1, or 2 years. The sample-to-sample variation in the concentration and activity of cytochrome P450, cytochrome b5, and NADPH-cytochrome c reductase was nominally affected by long-term storage of human liver microsomes at -80 degrees C, indicating there was no differential loss of cytochrome P450 activity, cytochrome b5 concentration, or NADPH-cytochrome c reductase activity. In study C, microsomes from a pool of human livers were subjected to 1, 2, 3, 5, 7, or 10 cycles of freezing at -80 degrees C followed by thawing at room temperature. Freezing/thawing liver microsomes for up to 10 cycles did not convert cytochrome P450 to P420, nor did it cause significant loss of CYP1A2, CYP2A6, CYP2C9, CYP2C19, CYP2D6, CYP2E1, CYP3A4/5, or CYP4A9/11 activity. Overall, these results suggest that our current methods for storing and processing human liver are well suited to preserving microsomal P450 enzyme activity.

Hospitalized psychiatric and medical patients and the clergy

Earlier research suggested that persons in a community with significant psychiatric disorders seek relief from their clergy as often as from trained mental-health professionals. In this research, contacts with clergy about current hospitalization by matched samples of inpatient psychiatric (N=51) and medical/surgical (N=50) patients were compared, as were responses to structured interviews about the importance of religion, religious affiliation, and participation, spiritual needs, and spiritual well-being. The findings suggest that the two groups were similar in demographics, the degree to which religion was a source of strength and comfort in their lives, and percentages reporting as having a clergy person; the group of hospitalized psychiatric patients was significantly less likely, however, than the sample of medical/surgical patients to have discussed their current hospitalization with their clergy persons. Possible causes for this difference as well as areas of further research are discussed.

Immunoelectron microscopy identification of early proliferating cells in rat liver tissue during hyperplasia induced by lead nitrate

Recent studies have suggested that hepatic stem cells may be involved in at least some forms of liver epithelial growth. To obtain further information on this controversial hypothesis, we treated rats with lead nitrate to induce liver growth and identified the cells undergoing early DNA synthesis by bromodeoxyuridine immunohistochemistry, using both light and electron microscopic detection methods. Eight hours after an intravenous injection of lead nitrate 100 mumol/kg, DNA synthesis was detected in a few scattered hepatocytes and in nonparenchymal cells in portal connective tissue. At the light microscopic level, identification of nonparenchymal cells was limited to bile duct epithelial cells. Other cell types were also labeled, but their identity could not be established. At the ultrastructural level, however, four types of nonparenchymal cells were identified as containing bromodeoxyuridine immunogold particles. These four types included bile duct epithelial cells, fibroblasts, macrophages and nondescript periductular cells. These periductular cells displayed certain ultrastructural features of bile duct cells but did not line a lumen or display microvilli on their apical membrane, nor did they reside within the bile duct basement membrane. Because proliferation of nonparenchymal cells in portal areas preceded that of hepatocytes, it is suggested that the former reaction reflects a direct mitogenic effect of lead nitrate and not an adaptive growth response secondary to parenchymal enlargement. However, whether DNA synthesis in periductular cells or bile duct cells reflects activation of hepatic stem cells cannot be established from the present morphological observations. If so, such a progenitor compartment must be dormant because it does not seem to play a functional role in this and other forms of adult liver epithelial growth.

A preliminary investigation of opinions and behaviors regarding advance directives for medical care

BACKGROUND

Advance directives are a means of promoting patient autonomy in end-of-life decisions but are used infrequently. A recent federal law requires healthcare organizations to provide information to patients about advance directives. This study explored attitudes and behaviors related to the use of advance directives in three areas: familiarity with advance directives, reasons for completing or not completing advance directives and preferences for receiving information about advance directives.

METHODS

A questionnaire was administered by personal interview to a nonrandomized convenience sample of 46 inpatients and 50 outpatients at a large, tertiary care, urban academic medical center in the summer of 1991.

RESULTS

Most respondents (77%) had heard of either the living will or durable power of attorney for healthcare, but only 52% correctly understood the purpose of these documents. Twenty-nine percent of the sample had executed an advance directive. Those who had advance directives were older and considered themselves less healthy than did those without advance directives. Unfamiliarity with advance directives and procrastination were cited most often as reasons for not having an advance directive. Most subjects (65%) had spoken with someone, usually a family member or close friend, about preferences for treatment during a critical illness. Although they had rarely discussed advance directives, 83% anticipated that they would be comfortable doing so with a physician or a nurse.

CONCLUSIONS

Advance directives are used infrequently to document treatment preferences. The success of programs to promote greater use of advance directives depends on a clearer understanding of the factors that influence both decision and action to execute an advance directive. Patients claim to be comfortable in discussing the topic and prefer that such discussions occur in the outpatient setting.

A preliminary investigation of opinions and behaviors regarding advance directives for medical care

BACKGROUND: Advance directives are a means of promoting patient autonomy in end-of-life decisions but are used infrequently. A recent federal law requires healthcare organizations to provide information to patients about advance directives. This study explored attitudes and behaviors related to the use of advance directives in three areas: familiarity with advance directives, reasons for completing or not completing advance directives and preferences for receiving information about advance directives. METHODS: A questionnaire was administered by personal interview to a nonrandomized convenience sample of 46 inpatients and 50 outpatients at a large, tertiary care, urban academic medical center in the summer of 1991. RESULTS: Most respondents (77%) had heard of either the living will or durable power of attorney for healthcare, but only 52% correctly understood the purpose of these documents. Twenty-nine percent of the sample had executed an advance directive. Those who had advance directives were older and considered themselves less healthy than did those without advance directives. Unfamiliarity with advance directives and procrastination were cited most often as reasons for not having an advance directive. Most subjects (65%) had spoken with someone, usually a family member or close friend, about preferences for treatment during a critical illness. Although they had rarely discussed advance directives, 83% anticipated that they would be comfortable doing so with a physician or a nurse. CONCLUSIONS: Advance directives are used infrequently to document treatment preferences. The success of programs to promote greater use of advance directives depends on a clearer understanding of the factors that influence both decision and action to execute an advance directive. Patients claim to be comfortable in discussing the topic and prefer that such discussions occur in the outpatient setting.

Visual field differences for clockwise and counterclockwise mental rotation

Geometric line drawings were presented to normal subjects in the left visual field (LVF) or right visual field (RVF) at various degrees of rotation from a centrally presented vertical standard. The task of the subject was to indicate with a reaction time (RT) response whether the laterally presented stimulus could be rotated into the vertical standard or if it was a rotated mirror image of the standard. In Study 1, an overall right hemisphere superiority was found for RT and accuracy on match trials. Most interestingly, interactions between Visual Field and Rotation Angle for the match accuracy data and between Visual Field and Direction of Rotation (clockwise or counterclockwise) for the match RT slopes were found. These interactions suggested that clockwise rotations were more readily performed in the LVF and counterclockwise rotations in the RVF, consistent with other literature for mental rotation. The purpose of Study 2 was to replicate this finding of visual field differences for rotation direction using a design in which direction and degree of rotation were varied orthogonally. No main effect of Visual Field was found. However, significant interactions between Visual Field and Rotation Angle were found for both RT and accuracy, confirming the presence of visual field differences for rotation direction in a new sample of subjects. These differences were discussed in terms of the possibly greater relevance of medially directed stimuli and a possible hemispheric bias for rotation direction, and in terms of interhemispheric transmission factors.

Communication about advance directives: are patients sharing information with physicians?

Historically, patients have deferred to physicians′ judgments about appropriate medical care, thereby limiting patient participation in treatment decisions. In this model of medical decision making, physicians typically decided upon the treatment plan. Communication with patients focused on securing their cooperation in accepting a treatment decision that essentially had already been made.

Effects of processing speed on cerebral asymmetry for left- and right-oriented faces

A free-vision chimeric facial emotion judgment task and a tachistoscopic face-recognition reaction time task were administered to 20 male right-handed subjects. The tachistoscopic task involved judgments of whether a poser in the centrally presented full-face photograph was the same or different poser than in a profile photograph presented in the left or right visual field (LVF, RVF). The free-vision task was that used by J. Levy, W. Heller, M. Banich, and L. Burton (1983, Brain and Cognition, 2, 404-419) and involved judging which of two chimeric faces appeared happier, in which the two chimeras were mirror images of each other and each chimera consisted of a smiling half-face joined at the midline to a neutral half-face of the same poser. For the tachistoscopic task, subjects were divided into groups of Fast and Slow responders by a median split of the mean reaction times. For the Fast subjects, judgments were faster in the LVF than in the RVF, and there was a significant interaction between visual field and profile direction, such that responses were faster for medially oriented profiles; i.e., LVF responses were faster for right-facing than for left-facing profiles, with the reverse relationship in the RVF. The Slow responders did not show these effects. Only the Fast group showed the bias for choosing the chimera with the smile on the left as happier, and mean response speed and the LVF advantage on the tachistoscopic test correlated with the leftward bias on the free-vision task for all subjects combined. It was suggested that overall response speed on the face-matching task reflected the extent to which specialized and more efficient right hemisphere functions were activated.

Sex differences in the lateralized processing of facial emotion

Two reaction time tasks were administered to male and female normal subjects, involving judgments of facial emotion. In the Word-Face task, judgments of similarity or difference of a centrally presented emotion word and an emotional face presented in the left or right visual field were required, and in the Face-Face task, comparisons of a centrally presented and a laterally presented emotional face were required. Results were significant for the matching trials only. Reaction times to negative emotions were faster overall than to positive emotions, and an Emotional Valence by Visual Field interaction was found such that reaction times were faster for negative emotions in the left visual field and for positive emotions in the right visual field. This interaction was significant for the female but not the male subjects, although similar patterns were observed in both sexes. Further, an interaction of Gender, Task, and Emotional Valence was found, such that the two tasks had opposite effects for the two sexes. The Face-Face task appeared to inhibit the performance of the male subjects and facilitate the performance of the female subjects in terms of reaction time. It was suggested that specifying the target emotion by an emotional face elicits a greater emotional response on the part of the subject than specification by a word, and that this emotional elicitation may result in a reactive inhibition in the male subjects and in an elaboration of the emotional response in the female subjects.

Asymmetry of perception in free viewing of chimeric faces

We have devised a new free-vision task to index functional cerebral asymmetry for processing facial characteristics. Confirming its sensitivity to properties of lateralized hemispheric functions, left- and right-handers were clearly differentiated on this task with respect to several aspects of performance that conform with known differences between handedness groups in hemispheric asymmetry. Additionally, there were highly reliable and stable individual differences in perceptual asymmetries within handedness. Analyses of items in the task revealed that most of the differences between items in the asymmetries they elicited were random.

Are variations among right-handed individuals in perceptual asymmetries caused by characteristic arousal differences between hemispheres?

We propose that much of the variance among right-handed subjects in perceptual asymmetries on standard behavioral measures of laterality arises from individual differences in characteristic patterns of asymmetric hemispheric arousal. Dextrals with large right-visual-field (RVF) advantages on a tachistoscopic syllable-identification task (assumed to reflect characteristically higher left-hemisphere than right-hemisphere arousal) outperformed those having weak or no visual-field asymmetries (assumed to reflect characteristically higher right-hemisphere than left-hemisphere arousal). The two groups were equal, however, in asymmetries of error patterns that are thought to indicate linguistic or nonlinguistic encoding strategies. For both groups, relations between visual fields in the ability to discriminate the accuracy of performance followed the pattern of syllable identification itself, suggesting that linguistic and metalinguistic processes are based on the same laterally specialized functions. Subjects with strong RVF advantages had a pessimistic bias for rating performance, and those with weak or no asymmetries had an optimistic bias, particularly for the left visual field (LVF). This is concordant with evidence that the arousal level of the right hemisphere is closely related to affective mood. Finally, consistent with the arousal model, leftward asymmetries on a free-vision face-processing task became larger as RVF advantages on the syllable task diminished and as optimistic biases for the LVF, relative to the RVF, increased.

Are variations among right-handed individuals in perceptual asymmetries caused by characteristic arousal differences between hemispheres?

We propose that much of the variance among right-handed subjects in perceptual asymmetries on standard behavioral measures of laterality arises from individual differences in characteristic patterns of asymmetric hemispheric arousal. Dextrals with large right-visual-field (RVF) advantages on a tachistoscopic syllable-identification task (assumed to reflect characteristically higher left-hemisphere than right-hemisphere arousal) outperformed those having weak or no visual-field asymmetries (assumed to reflect characteristically higher right-hemisphere than left-hemisphere arousal). The two groups were equal, however, in asymmetries of error patterns that are thought to indicate linguistic or nonlinguistic encoding strategies. For both groups, relations between visual fields in the ability to discriminate the accuracy of performance followed the pattern of syllable identification itself, suggesting that linguistic and metalinguistic processes are based on the same laterally specialized functions. Subjects with strong RVF advantages had a pessimistic bias for rating performance, and those with weak or no asymmetries had an optimistic bias, particularly for the left visual field (LVF). This is concordant with evidence that the arousal level of the right hemisphere is closely related to affective mood. Finally, consistent with the arousal model, leftward asymmetries on a free-vision face-processing task became larger as RVF advantages on the syllable task diminished and as optimistic biases for the LVF, relative to the RVF, increased.