Prevalence and Preventability of Adverse Medicine Events in a Sample of Australian Aged-Care Residents: A Secondary Analysis of Data from the ReMInDAR Trial

BACKGROUND

Aged care residents are vulnerable to the harmful effects of medicines; however, data on the prevalence and preventability of adverse medicine events in aged care residents are scarce.

AIM

To determine the prevalence and preventability of adverse medicine events in Australian aged care residents.

METHODS

A secondary analysis of data from the Reducing Medicine-Induced Deterioration and Adverse Reactions (ReMInDAR) trial was conducted. Potential adverse medicine events were identified and independently screened by two research pharmacists to produce a short-list of potential adverse medicine events. An expert clinical panel reviewed each potential adverse medicine to determine the likelihood that the event was medicine related (based on the Naranjo Probability Scale criteria). The clinical panel assessed preventability of medicine-related events using Schumock-Thornton criteria.

RESULTS

There were 583 adverse events due to medicines, involving 154 residents (62% of the 248 study participants). There was a median of three medication-related adverse events (interquartile range [IQR] 1-5) per resident over the 12-month follow-up period. The most common medication-related adverse events were falls (56%), bleeding (18%) and bruising (9%). There were 482 (83%) medication-related adverse events that were preventable, most commonly falls (66% of preventable adverse medicine events), bleeding (12%) and dizziness (8%). Of the 248 residents, 133 (54% of the cohort) had at least one preventable adverse medicine event, with a median of 2 (IQR 1-4) preventable adverse medicine events per resident.

CONCLUSION

In total, 62% of aged care residents in our study had an adverse medicine event and 54% had a preventable adverse medicine event in a 12-month period.

Preventing Adverse Drug Reactions After Hospital Discharge (PADR-AD): Protocol for a randomised-controlled trial in older people

BACKGROUND

Adverse drug reactions (ADRs) and adverse drug events (ADEs) in older people contribute to a significant proportion of hospital admissions and are common following discharge. Effective interventions are therefore required to combat the growing burden of preventable ADRs. The Prediction of Hospitalisation due to Adverse Drug Reactions in Elderly Community Dwelling Patients (PADR-EC) score is a validated risk score developed to assess the risk of ADRs in people aged 65 years and older and has the potential to be utilised as part of an intervention to reduce ADRs.

OBJECTIVES

This trial was designed to investigate the effectiveness of an intervention to reduce ADR incidence in older people and to obtain further information about ADRs and ADEs in the 12-24 months following hospital discharge.

METHODS

The study is an open-label randomised-controlled trial to be conducted at the Royal Hobart Hospital, a 500-bed public hospital in Tasmania, Australia. Community-dwelling patients aged 65 years and older with an unplanned overnight admission to a general medical ward will be recruited. Following admission, the PADR-EC ADR score will be calculated by a research pharmacist, with the risk communicated to clinicians and discussed with participants. Following discharge, nominated general practitioners and community pharmacists will receive the risk score and related medication management advice to guide their ongoing care of the patient. Follow-up with participants will occur at 3 and 12 and 18 and 24 months to identify ADRs and ADEs. The primary outcome is moderate-severe ADRs at 12 months post-discharge, and will be analysed using the cumulative incidence proportion, survival analysis and Poisson regression.

SUMMARY

It is hypothesised that the trial will reduce ADRs and ADEs in the intervention population. The study will also provide valuable data on post-discharge ADRs and ADEs up to 24 months post-discharge.

Medication Regimen Complexity Index Prediction of Adverse Drug Reaction-Related Hospital Admissions

BACKGROUND

The relationship between the medication regimen complexity index (MRCI) and adverse drug reaction (ADR)-related hospital admissions has not yet specifically been investigated.

OBJECTIVE

To evaluate the MRCI and compare with medication count for prediction of ADR-related hospital admissions in older patients.

METHODS

This was a retrospective analysis of a prospectively collected convenience sample of 768 unplanned medical admissions of Australians aged 65 years old and older. The sample consisted of 115 (15.0%) ADR-related unplanned hospital admissions and 653 (85.0%) non-ADR-related unplanned medical admissions. The MRCI score was calculated from the medical records and analyzed to predict ADR-related hospital admissions.

RESULTS

The cohort had a median age of 81 years, 5 comorbidities, and 11 medications, with a slight majority of women. The MRCI score was not significantly different in patients who had ADR-related admissions compared with other medical admissions-38.5 versus 34.0, respectively; Wilcoxon Rank Sum test W = 33 522; P = 0.067. The medication count was significantly different between the ADR-related admissions compared with other medical admissions: 12 versus 10; W = 32 508; P = 0.021. However, the medication count was not a strong predictor of ADR-related admissions; unadjusted odds ratio = 1.044; 95% CI = 1.006-1.084.

CONCLUSION AND RELEVANCE

The MRCI score did not discriminate between ADR-related admissions and other medical admissions despite taking time to calculate with potential for inconsistent application. Medication count is more readily applicable with marginally greater relevance in this cohort; however, both measures do not appear to be useful when used alone for clinicians to identify patients at risk of ADRs.

Adverse Drug Reaction-Related Hospitalizations in Elderly Australians: A Prospective Cross-Sectional Study in Two Tasmanian Hospitals

INTRODUCTION

Adverse drug reactions (ADRs) have been commonly cited as a major cause of hospital admissions in older individuals. However, despite the apparent magnitude of this problem, there are limited prospective data on ADRs as a cause of hospitalization in elderly medical patients.

OBJECTIVES

The objective of this study was to evaluate the proportion, clinical characteristics, causality, severity, preventability, and outcome of ADR-related admissions in older patients admitted to two Tasmanian hospitals.

METHODS

We conducted a prospective cross-sectional study at the Royal Hobart and Launceston General Hospitals in Tasmania, Australia. A convenience sample of patients, aged 65 years and older, undergoing unplanned overnight medical admissions was screened. ADR-related admissions were determined through expert consensus from detailed review of medical records and patient interviews. The causality, preventability and severity of each ADR-related admission were assessed.

RESULTS

Of 1008 admissions, the proportion of potential ADR-related medical admissions was 18.9%. Most (88.5%) ADR-related admissions were considered preventable. Cardiovascular complaints (29.3%) represented the most common ADRs, followed by neuropsychiatric (20.0%) and renal and genitourinary disorders (15.2%). The most frequently implicated drug classes were diuretics (23.9%), agents acting on the renin angiotensin system (16.4%), β-blocking agents (7.1%), antidepressants (6.9%), and antithrombotic agents (6.9%). Application of the Naranjo algorithm found 5.8% definite, 70.1% probable, and 24.1% possible ADRs. ADR severity was rated moderate and severe in 97.9% and 2.1% of admissions, respectively. For most (93.2%) ADR-related admissions the ADR resolved and the patient recovered.

CONCLUSION

Hospitalization due to an ADR is a common occurrence in this older population. There is need for future studies to implement and evaluate interventions to reduce the risk of ADR-related admissions in elderly populations.

Repeat Adverse Drug Reaction-Related Hospital Admissions in Elderly Australians: A Retrospective Study at the Royal Hobart Hospital

BACKGROUND

Adverse drug reactions are a major cause of hospital admissions in older individuals, with the majority potentially preventable. Despite the apparent magnitude of this problem, little is known about rates of repeat admission to hospital as a result of adverse drug reactions.

OBJECTIVES

The objectives of this study were to investigate the occurrence of repeat adverse drug reaction-related hospital admissions in elderly patients within 12 months of an adverse drug reaction-related admission to a medical ward and whether a validated adverse drug reaction score could be useful in identifying patients at higher risk of a repeat adverse drug reaction-related hospitalisation.

METHODS

This retrospective study followed elderly participants who were hospitalised with an adverse drug reaction from our earlier study [the PADR-EC (Prediction of Hospitalization due to Adverse Drug Reactions in Elderly Community-Dwelling Patients) study] to identify repeat adverse drug reaction-related hospital admissions within 12 months of discharge. The PADR-EC score is the sum of points assigned to five significant predictors of adverse drug reaction-related hospitalisation: antihypertensive use, renal failure, dementia, inappropriate anticholinergic use and drug changes in the preceding 3 months. The causality, preventability and severity of each adverse drug reaction-related repeat admission within the 12-month follow-up were assessed.

RESULTS

Adverse drug reaction-related repeat admissions occurred after 13.4% (n = 15) of 112 adverse drug reaction-related index admissions. Patients with a repeat adverse drug reaction-related admission had significantly higher PADR-EC scores at discharge of their index admission (median PADR-EC score 7, interquartile range 7-9) than patients who were not readmitted (median PADR-EC score 7, interquartile range 5-7, p = 0.034). Most (73.3%) adverse drug reaction-related repeat admissions were considered 'preventable'. Adverse drug reaction severity was 'moderate' in all cases. Renal disorders (44.4%) represented the most common adverse drug reactions and the most frequently implicated drug classes were diuretics (44.8%). All adverse drug reaction-related repeat admissions were found to be 'probable'.

CONCLUSIONS

One in eight elderly patients hospitalised because of an adverse drug reaction had a repeat admission for an adverse drug reaction within 12 months of discharge. The PADR-EC score could potentially be used at hospital discharge to prioritise patients for interventions to prevent subsequent adverse drug reaction-related hospital admissions.

Prediction of Hospitalization due to Adverse Drug Reactions in Elderly Community-Dwelling Patients (The PADR-EC Score)

BACKGROUND

Adverse drug reactions (ADRs) are the major cause of medication-related hospital admissions in older patients living in the community. This study aimed to develop and validate a score to predict ADR-related hospitalization in people aged ≥65 years.

METHODS

ADR-related hospitalization and its risk factors were determined using a prospective, cross-sectional study in patients aged ≥65 years admitted to two hospitals. A predictive model was developed in the derivation cohort (n = 768) and the model was applied in the validation cohort (n = 240). ADR-related hospital admission was determined through expert consensus from comprehensive reviews of medical records and patient interviews. The causality and preventability of the ADR were assessed based on the Naranjo algorithm and modified Schumock and Thornton criteria, respectively.

RESULTS

In the derivation sample (mean [±SD] age, 80.1±7.7 years), 115 (15%) patients were admitted due to a definite or probable ADR; 92.2% of these admissions were deemed preventable. The number of antihypertensives was the strongest predictor of an ADR followed by presence of dementia, renal failure, drug changes in the preceding 3 months and use of anticholinergic medications; these variables were used to derive the ADR prediction score. The predictive ability of the score, assessed from calculation of the area under the receiver operator characteristic (ROC) curve, was 0.70 (95% confidence interval (CI) 0.65-0.75). In the validation sample (mean [±SD] age, 79.6±7.6 years), 30 (12.5%) patients' admissions were related to definite or probable ADRs; 80% of these admissions were deemed preventable. The area under the ROC curve in this sample was 0.67 (95% CI 0.56-0.78).

CONCLUSIONS

This study proposes a practical and simple tool to identify elderly patients who are at an increased risk of preventable ADR-related hospital admission. Further refinement and testing of this tool is necessary to implement the score in clinical practice.

Hospitalization in older patients due to adverse drug reactions -the need for a prediction tool

Adverse drug reactions (ADRs) represent a major burden on society, resulting in significant morbidity, mortality, and health care costs. Older patients living in the community are particularly susceptible to ADRs, and are at an increased risk of ADR-related hospitalization. This review summarizes the available evidence on ADR-related hospital admission in older patients living in the community, with a particular focus on risk factors for ADRs leading to hospital admission and the need for a prediction tool for risk of ADR-related hospitalization in these individuals. The reported proportion of hospital admissions due to ADRs has ranged from 6% to 12% of all admissions in older patients. The main risk factors or predictors for ADR-related admissions were advanced age, polypharmacy, comorbidity, and potentially inappropriate medications. There is a clear need to design intervention strategies to prevent ADR-related hospitalization in older patients. To ensure the cost-effectiveness of such strategies, it would be necessary to target them to those older individuals who are at highest risk of ADR-related hospitalization. Currently, there are no validated tools to assess the risk of ADRs in primary care. There is a clear need to investigate the utility of tools to identify high-risk patients to target appropriate interventions toward prevention of ADR-related hospital admissions.

Differences in symptomatology and diagnostic profile in younger and elderly depressed inpatients

BACKGROUND

Depression is the most prevalent psychiatric disorder in the elderly and several studies indicate that 10-15% of persons over 65 years suffer from significant depressive symptoms. Despite the high prevalence, most cases of depression in the elderly remain unrecognized and untreated, maybe because of a different pattern of symptoms across age groups. The objective of the study was to compare symptomatology and diagnostic profile between younger and elderly DSM-III and DSM-III-R major depressed inpatients and to advise an appropriate depression scale for the elderly.

METHODS

The study covers 461 depressed inpatients evaluated with the Hamilton Depression Scale and the Newcastle 1965 Scale. To find differences between younger and elderly patients, the symptomatology was analyzed stepwise by principal component analyses, latent structure analyses and single item analyses.

RESULTS

No clinically significant differences in symptomatology between younger and elderly depressed patients were found. The DSM-IV concept of Major Depression and the ICD-10 criteria for depression was not influenced by patients' age.

LIMITATIONS

All patients were hospitalized and mainly endogenously depressed and generalization of the results to other populations should be made with caution. Only pretreatment data was analyzed.

CONCLUSIONS

The DSM-IV concept of Major Depression and the ICD-10 criteria for depression can be used without modification for age.

Increased cortisol levels and impaired cognition in human aging: implication for depression and dementia in later life

Perhaps the most prominent feature of human aging is the variability in decline of intellectual processes. Although many research avenues have been used to study the origin of such an increased variability with aging, new studies show that some biological factors may be associated with normal and pathological cognitive aging. One biological parameter that came under scrutiny in the past few years is the hypothalamic-pituitary-adrenal (HPA) axis, an endocrine closed-loop system controlling the secretion of stress hormones (glucocorticoids). In this review, we summarize data obtained in both animals and humans suggesting that cumulative exposure to high levels of glucocorticoids can be particularly detrimental for the aged hippocampus, a brain structure involved in learning and memory in both animals and humans. We then analyze the implication of these data for the study of dementia and depression in later life, two disorders characterized by increased glucocorticoid secretion in a significant proportion of patients. Finally, we suggest various factors that could explain the development of glucocorticoid hypersecretion in later life.

Alzheimer's disease may not be a spirochetosis

It has been reported previously that spirochetes could be one of the causes of Alzheimer's disease (AD). In this study, we have attempted to reproduce these findings by examining fresh blood samples from 22 patients diagnosed with early stage (n = 16) and late stage (n = 6) AD. The patients were participants in a clinical drug trial. Fresh necropsy brain cortical specimens from AD patients (n = 7) were also examined. Spirochetes were observed microscopically in the blood of only one late-stage AD patient. None of the brain tissues showed the presence of spirochetes. Our results suggest that spirochetes are probably not associated with AD.

Cortisol levels during human aging predict hippocampal atrophy and memory deficits

Elevated glucocorticoid levels produce hippocampal dysfunction and correlate with individual deficits in spatial learning in aged rats. Previously we related persistent cortisol increases to memory impairments in elderly humans studied over five years. Here we demonstrate that aged humans with significant prolonged cortisol elevations showed reduced hippocampal volume and deficits in hippocampus-dependent memory tasks compared to normal-cortisol controls. Moreover, the degree of hippocampal atrophy correlated strongly with both the degree of cortisol elevation over time and current basal cortisol levels. Therefore, basal cortisol elevation may cause hippocampal damage and impair hippocampus-dependent learning and memory in humans.

Therapeutic equivalence of risperidone given once daily and twice daily in patients with schizophrenia. The Risperidone Study Group

A study was conducted to determine whether once-daily administration of risperidone was as effective and safe as twice-daily administration. In a double-blind 6-week trial, 211 patients with acute exacerbation according to DSM-III-R criteria were randomly assigned to receive risperidone at 8 mg once daily or 4 mg twice daily. The primary efficacy measure was the treatment response rate, defined as a 20% or greater reduction in total Positive and Negative Syndrome Scale (PANSS) scores. Severity of extrapyramidal symptoms was assessed by the Extrapyramidal Symptom Rating Scale. The percentage of patients who showed a treatment response at endpoint was not significantly different between groups (76%, once-daily; 72%, twice-daily), nor was the median time to first treatment response (14 days, both groups). Significant reductions in PANSS total and subscale scores and PANSS-derived Brief Psychiatric Rating Scale were observed in both groups, with no significant between-group differences. Extrapyramidal Symptom Rating Scale scores did not differ significantly between groups. There were no clinically relevant changes in vital signs, electrocardiograms, or clinical laboratory test results in either group. Gradual dosage titration over the first 3 days of treatment was well-tolerated in both groups. The median trough plasma concentrations of risperidone, 9-hydroxyrisperidone, and risperidone plus 9-hydroxyrisperidone were significantly lower with once-daily than with twice-daily administration; median plasma concentrations measured within the first 8 hours after administration tended to be higher with once-daily administration. These differences did not affect the safety and efficacy of risperidone. Risperidone given once daily at 8 mg is as effective as twice-daily administration of 4 mg in the treatment of acute exacerbations of schizophrenia. Both regimens were equally well-tolerated.

The dexamethasone suppression test and treatment outcome in elderly depressed patients participating in a placebo-controlled multicenter trial involving moclobemide and nortriptyline

The dexamethasone suppression test (DST) was conducted in 95 elderly DSM-III-R depressed patients randomized for treatment with moclobemide (MOC; 400 mg daily), nortriptyline (NT; 75 mg daily), or placebo (PBO) in a 7-week double-blind multicenter study. Patients were assessed weekly using various clinical scales, including the 17-item Hamilton Depression Rating Scale. The DST was administered at baseline and at the end of treatment. At baseline, no relationship was found between DST status and the various clinical scales used. At the end of treatment, suppressors (DST-) had significantly improved clinical ratings compared to nonsuppressors (DST+), and were mostly found among those treated with NT (71%) as compared to MOC (41%) or PBO (33%) (p < .03). On the other hand, baseline DST measures influenced treatment outcome; DST+ patients had a greater number of treatment responders to NT (48%) than MOC (19%) or PBO (20%) (p < .07). For DST- patients, the situation was reversed: NT, 7%; MOC, 31%. Postdexamethasone cortisol levels were lower in MOC responders (p < .07). An interaction was found between DST and drug-specific response. The DST may be a useful adjunct for predicting and evaluating the outcome of antidepressant therapy.

Treatment of Alzheimer's disease with sabeluzole: functional and structural correlates

Sabeluzole, a new benzothiazole derivative, has been shown to be neurobiologically active preclinically and clinically appears to exert beneficial effects on memory. In this study, sabeluzole (5 or 10 mg twice daily vs. placebo) was investigated in patients with probable Alzheimer's disease over 1 year, with assessments of cognitive performance and structural changes. Cognitive performance was measured using the Alzheimer's Disease Assessment Scale periodically during treatment. Potential structural correlates in the frontal horn, caudate, third ventricle and hippocampal regions were examined by obtaining computerized tomographic (CT) images before and after treatment. Patients receiving sabeluzole evidenced greater stability than did placebo-treated patients in some cognitive measures. CT measures showed no significant changes from baseline, but some weak associations were found between relative preservation of cognitive function and smaller structural declines in the third ventricle and hippocampus. Cognitive outcome measures suggest that sabeluzole may have potential in slowing the cognitive deterioration of Alzheimer's disease. Furthermore, the method used to explore potential benefits on a morphologic level, although negative in this study, could yet have potential.

Stress-induced declarative memory impairment in healthy elderly subjects: relationship to cortisol reactivity

A group of 14 healthy elderly subjects was submitted to a nonstressful (attentional task) and a stressful (public speaking task) condition. Declarative (conscious recollection of learned information) and nondeclarative (retrieved information without conscious or explicit access) memory as well as salivary cortisol levels were measured before and after each condition. The results showed that the stressful condition significantly decreased declarative memory performance, whereas the nonstressful condition did not. Nondeclarative memory performance was not affected by either condition. Further analyses separating the subjects into responders and nonresponders in terms of stress-induced cortisol changes revealed a very different pattern of cortisol secretion and declarative memory performance in both populations. We showed that the responders presented increased cortisol levels 60 min before the actual stressor, whereas the nonresponders presented increased cortisol levels 25 min before the actual stressor. Although the responders did not differ from the nonresponders in declarative memory performance before and after the nonstressful condition, they presented a lower declarative memory performance when measured before and after the stressful condition. The early increase in cortisol levels observed in the responder group suggests that the anticipation of the stress, rather than the actual stressor per se, may have played a more significant role in the stress-induced declarative memory deficits observed in this subgroup. Together, these results show that the cortisol response to anticipation of stress and/or to stress in the elderly specifically affects those memory functions that are dependent on hippocampal activity. They also suggest that an altered cortisol responsivity to acute and/or chronic stress, with its detrimental effects on memory, could be an important factor explaining the genesis of memory deficits in aged populations.

The Major Depression Rating Scale (MDS). Inter-rater reliability and validity across different settings in randomized moclobemide trials. Danish University Antidepressant Group

The Major Depression Rating Scale (MDS) has been derived from the Hamilton Depression Scale and the Melancholia Scale. The MDS contains the nine DSM-IV items for major depression which all have anchoring scores from 0 to 4; hence, the theoretical score range is up to 36. The Major Depression Rating Scale has in this study been psychometrically analysed in randomized moclobemide trials. The results showed that the MDS had higher internal validity than the Hamilton Depression Scale. Thus, the homogeneity of the items was higher; factor analysis identified only one general depression factor (after 4 weeks of treatment explaining more than 50% of the variance). The inter-rater reliability of the two scales was of the same high level. The ability to measure changes (external validity) was tested in randomized clinical trials with moclobemide versus tricyclics (clomipramine and notriptyline) performed in Denmark in the psychiatric setting as well as in the general practice. The results showed that in the psychiatric setting tricyclics were superior to moclobemide with effect sizes ranging between 0.43 and 0.53. The highest effect size was obtained with the Melancholia Scale and the Major Depression Rating Scale, while the Hamilton Depression Scale was below 0.50. In the general practice setting no difference was found between moclobemide and clomipramine. In conclusion, the Major Depression Rating Scale has been found to have a more homogeneous factor structure than the Hamilton Depression Scale, but still with the same level of reliability and external validity. However, studies are needed to standardize the scale, especially in the general practice setting.

Effect of sleep deprivation on the growth hormone response to the alpha-3 adrenergic receptor agonist, clonidine, in normal subjects

One night's sleep deprivation (SD) increased the growth hormone (GH) response to clonidine (20 ug/kg i.v.) in 11 normal men ( p < 0.005). This finding may indicate that SD enhances alpha-2 adrenergic receptor function or that the GH response to GH releasing factor in increased by SD.

Psychogeriatric clinical, electro-encephalographic and autopsy findings

Demographic, psychiatric, and electro-encephalographic (EEG) data were compared with brain autopsy findings for 73 elderly psychiatric patients. A late onset of depression (60+ years) was more likely than early onset to be accompanied by Alzheimer's disease. There were strong associations between clinical and histopathological indicators of Alzheimer's disease. This was particularly evident for diffuse EEG slowing. Clinical as well as histopathological indicators of Alzheimer's disease were intensely related to EEG features, mainly EEG slowness (positive), reactivity to eye opening (negative) and dominant frequency (negative). Cerebrovascular pathology showed fewer EEG correlations. The results support the usefulness of the clinical electro-encephalogram in patients suspected to have Alzheimer's disease.

Cardiovascular, neuroendocrine, and monoaminergic responses to psychological stressors: possible differences between remitted panic disorder patients and healthy controls

Both clinical symptomatology and stress research suggest that panic attacks might be partially attributable to exaggerated psychophysiological responses to environmental stressors. In the present study, we aimed to explicitly test this idea by measuring the physiological responses to a mild psychological stressor in both healthy controls (n = 8) and fully remitted, medication-free panic disorder patients (n = 8). One hour before the stressor, former patients, compared to healthy controls, exhibited higher diastolic blood pressure. From a blood sample taken 30 min before the stressor, patients, compared to controls, had lower paroxetine platelet binding site densities. During the stressor, patients, compared to controls, had greater increases in plasma levels of cortisol. These preliminary findings suggest that remitted panic disorder patients might have disturbed physiological responses to mild psychological stressors. These disturbances might be related to the development of future episodes.

Clinical relevance of serum nortriptyline and 10-hydroxy-nortriptyline measurements in the depressed elderly: a multicenter pharmacokinetic and pharmacodynamic study

In a recent placebo-controlled multicenter study, 38 patients, ranging in age between 62 and 88 years (median, 71) were treated with nortriptyline (NT) for up to 7 weeks. NT was administered in a divided dose of 75 mg daily and serum NT (se NT), and its 10-hydroxy-metabolites (se OH-NT) were determined at various intervals. Several clinical measures of efficacy, including the 17-item Hamilton Rating Scale for Depression, were evaluated weekly as well as side effects (anticholinergic) and electrocardiogram (ECG) changes. Eighty-one percent of patients had NT levels in the previously defined therapeutic range of 50 to 170 ng/ml, with steady state reached between 1 and 3 weeks. There was little individual variation in drug kinetics and metabolism over the study period. In general se OH-NT levels were not greater than those of se NT. Pharmacodynamic analyses showed that patients with moderate to severe anticholinergic side effects [CSE(+)] had significantly higher NT levels than those with mild or no symptoms [CSE(-)]. Furthermore, repeated-measures ANOVA modeled over time showed a highly significant decrease in clinical measures in both CSE groups of patients and also a highly significant group-time interaction. Higher se OH-NT levels were associated with less anticholinergic side effects. No ECG changes were observed.

The effect of Yohimbine, an alpha2 adrenergic receptor antagonist, on the growth hormone response to apomorphine in normal subjects

Yohimbine HCl (16 mg po) administered 30 min before clonidine (CLON) (2 ug/kg infused over 10 min) (N = 5) or apomorphine HCl (Apo) (0.5 mg sc) (N = 10) antagonized the growth hormone (GH) response to CLON but had no effect on the GH response to Apo in normal men. This finding suggests that in humans, alpha2 adrenergic mechanisms do not modulate dopaminergic function, at least not in the hypothalamic-pituitary axis, and that the GH response to Apo is not mediated via an alpha2 adrenergic link.

Outcome variables in presymptomatic individuals at higher risk of developing Alzheimer disease

The treatment of individuals at risk of Alzheimer disease is feasible in well-designed, placebo-controlled, double-blind studies. The favored design would be life survival for cognitive impairment, alterations in instrumental ADL, and selected biological variables.

Comparison of fluvoxamine, imipramine, and placebo in the treatment of outpatients with panic disorder

Fluvoxamine and imipramine were compared to placebo in an 8-week doubleblind randomized multicentre trial comprising of 148 outpatients between 19 and 57 years of age (mean: 35) with a DSM-III-R diagnosis of Panic Disorder. mean daily dose at endpoint was: fluvoxamine, 171.4 mg; imipramine 164.7 mg. The mean number of panic attacks per week at baseline were 10.9, 14.4 and 6.5 for fluvoxamine, imipramine and placebo, respectively. The intent-to-treat analysis of the change from baseline (difference score) of the number of panic attacks at endpoint revealed: a difference of 3.3 attacks (95% CI: -0.3, 6.8) between fluvoxamine and placebo and a difference of 6.0 attacks (95% CI: 1.5, 10.5) between imipramine and placebo. Treatment was stopped prematurely in 31 (62%) on fluvoxamine, 16 (33%) on imipramine and 29 (58%) on placebo. The number of patients withdrawing due to intolerance was 13 (26%) for fluvoxamine, 10 (21%) for imipramine and 4 (8%) for placebo. The number of patients withdrawing due to lack of efficacy was 10 (20%) for fluvoxamine, 4 (8%) for imipramine and 12 (24%) for placebo. Overall, this study demonstrated that fluvoxamine was not effective in the treatment of panic disorder but did show a strong effect for imipramine. A chance occurrence of significantly fewer number of panic attacks in the placebo group at baseline may limit the conclusions of this study.

Longitudinal study of basal cortisol levels in healthy elderly subjects: evidence for subgroups

A group of 51 healthy elderly volunteer subjects participated in a 3- to 6-year longitudinal study of basal cortisol levels. Once per year basal cortisol levels were examined using hourly sampling over a 24-h period. Analyses of three cortisol measures (last measure obtained, mean cortisol levels across years, and the cortisol slope) revealed that the slope of the regression line measuring cortisol levels at each year was the most predictive measure of cortisol secretion over the years in this elderly population. Cortisol levels were shown to increase with years in one subgroup, to decrease in another, and to remain stable in a third. The age of the subjects was not related to either cortisol levels or to the pattern of change in cortisol secretion over years. Free and total cortisol levels were highly correlated and the groups did not differ with regard to plasma corticosteroid binding globulin. No group differences were observed for weight, height, body mass index, pulse, blood pressure and glucose. However, significant group differences were reported for plasma triglycerides levels as well as high density lipoproteins levels. Positive correlations were reported between the obsession/compulsion subscale of the SCL-90 questionnaire and the cortisol slope of subjects. Finally, previously reported group differences in neuropsychological performance are summarized. Thus, there exists considerable variation in hypothalamo-pituitary-adrenal function amongst aged humans. These results are consistent with recent animal studies showing the existence of subpopulations of aged rats which differ in hypothalamo-pituitary-adrenal activity and cognitive efficiency.

An open study of tolerability and pharmacokinetics of raclopride extended release capsules in psychiatric patients: a Canadian study

The tolerability and pharmacokinetics of raclopride extended release (ER) capsules have been evaluated after a single oral dose and at steady state, with 3 different daily doses in 4 male patients requiring neuroleptic treatment. In this 3-week open study, the drug was administered to patients in increasing bid doses of 8 mg, 12 mg and 16 mg, respectively, for each 1-week treatment period, following a 1-week placebo washout. With this limited number of patients, assessments of clinical chemistry, hematology, cardiovascular variables and adverse symptoms suggest that raclopride is safe and well-tolerated in the group studied. The administration of repeated doses of raclopride showed linear pharmacokinetics based on parameter values which are either constant (effective elimination half-life, total plasma clearance, and dose-normalized area under the plasma concentration-time curve) or varying proportionally (trough plasma concentration, peak plasma concentration, average plasma concentration and the area under the plasma concentration-time curve for a dosage interval at steady state) with the doses. The linear 1-compartment open model with zero-order absorption was the most appropriate pharmacokinetic model describing the raclopride plasma concentration profile after a single 8 mg dose of raclopride ER capsules. The ER formulation reduced the fluctuation between peak and trough plasma drug concentrations which has been reported before with instant release dosage forms. In this study, the increase of plasma prolactin concentrations above the normal limit was transient and returned to normal levels. Although the plasma prolactin concentration tended to increase with the drug dose, no direct relationship between raclopride dose and prolactin plasma concentrations was found. The correlation of plasma prolactin response with the plasma raclopride concentration showed a low level of hysteresis.

Individual differences in hypothalamic-pituitary-adrenal activity in later life and hippocampal aging

Variation in magnitude of cognitive decline in later life is a central feature of human aging. The more severe forms of dementias, such as Alzheimer's disease, clearly define one end of the spectrum. However, among those showing no obvious signs of clinical dementia there are considerable individual differences. Thus, although evidence for learning, memory, and language loss appears in some individuals as early as 50-55 years of age, many people continue to function alertly well into their 90s. These individuals exemplify what Rowe and Kahn (1987) have termed "successful" aging. The wide variability in CNS aging, often a nuisance factor in studies, are becoming a major focus for brain aging research (e.g., Gage et al., 1984;Gallager and Pelleymounter, 1988; Aitken and Meaney, 1990; Issa et al., 1990). Our studies over the past few years have added support to the idea that individual differences in hypothalamic-pituitary-adrenal (HPA) activity can account for part of the variation seen in neurological function among the elderly. In this article we discuss the evidence for the idea that adrenal glucocorticoids can compromise hippocampal function and, thus, produce cognitive impairments, as well as the potential mechanisms for these effects.

Reversible and selective inhibitors of monoamine oxidase A in the treatment of depressed elderly patients

The treatment of depression in the elderly population needs a thorough and careful work-up and an aggressive therapeutic approach. Any treatment initiative in this population often becomes difficult because of accompanying physical illness, concomitant medication, possible degenerative changes in central nervous system and age-related altered metabolic status. Despite unevenness in research findings, pharmacological treatment remains the mainstay of management of depression among elderly people. Currently available antidepressants, although effective, are problematic because of the increased vulnerability of the elderly to side effects. Recent research efforts to improve the efficacy and safety of drug treatment of depression resulted in development of reversible and selective monoamine oxidase inhibitors of the isoenzyme A (RIMA), with antidepressant efficacy comparable to tricyclic antidepressants and newer generation antidepressants. RIMAs include moclobemide, brofaromine, toloxatone and cimoxatone. Moclobemide is the most investigated available RIMA for therapeutic use at present. Its absorption and disposition in elderly individuals do not differ significantly from those in young healthy volunteers and depressed patients. The results of present clinical studies show that, in elderly depressed patients, moclobemide is at least as effective as other antidepressants. Its particular advantage is, however, that it is as well tolerated in elderly people as in younger people. There are only few significant adverse events, and they are generally less frequent and less severe than those with TCAs. An additional attribute of moclobemide seems also to be its beneficial effect on cognitive functions.

Moclobemide and nortriptyline in elderly depressed patients. A randomized, multicentre trial against placebo

Moclobemide and nortriptyline were compared with placebo in a double-blind randomized multinational (Canada, Denmark and UK) trial comprising 109 patients of > 60 years of age with major depression (DSM-III-R). Patients were randomized to 7 weeks of treatment with doses of 400 mg/day moclobemide, 75 mg/day nortriptyline or placebo. It was necessary to adjust nortriptyline dosage in < 20% of patients to maintain serum levels within the postulated therapeutic window of 50-170 ng/ml. At end of treatment, the remission rates were 23% for moclobemide, 33% for nortriptyline and 11% for placebo. Anticholinergic and orthostatic events occurred more often with patients on nortriptyline than either moclobemide or placebo.

A Canadian multicentre placebo-controlled study of a fixed dose of brofaromine, a reversible selective MAO-A inhibitor, in the treatment of major depression

In a 6-week double-blind study, 220 patients with major depression (mostly outpatients) were randomly assigned to receive a fixed dose of brofaromine 150 mg daily (n = 111) or placebo (n = 109) after a 1-week single-blind placebo washout. Except for the HAM-D sleep items, brofaromine was superior to placebo on measures of depression as determined by the four methods of assessing drug efficacy: (1) psychiatric symptom rating (HAM-D 17-item less the three sleep items); (2) self-rating scale (Beck Depression Inventory); (3) Clinical Global Assessment of Efficacy; and (4) drop-out rate due to lack of efficacy. Most commonly reported adverse events with brofaromine were: headache, nausea, dizziness and sleep disturbance. Brofaromine was found to be an effective antidepressant, superior to placebo with a good tolerability profile.

Studies of a neurochemical link between depression, anxiety, and stress from [3H]imipramine and [3H]paroxetine binding on human platelets

We measured platelet [3H]imipramine and [3H]paroxetine binding in patients with major depression (n = 11), dysthymia (n = 9), generalized anxiety (n = 18) and panic disorder (n = 10), and in healthy controls (n = 13). The [3H]imipramine binding capacity (Bmax) was lower in all patient groups; [3H]paroxetine binding was reduced in anxiety disorders, however, decreases in depression and dysthymia were not significant. There were no differences in the affinity constant (Kd) for either radioligand. We also examined the effects of examination stress on platelet binding in medical students. Compared to after vacation, when binding was similar to controls, [3H]imipramine (n = 19) and [3H]paroxetine (n = 14) Bmax values were significantly decreased during examinations and similar to patient values. Examinations were also associated with an increase in plasma cortisol levels. These findings suggest that there is a neurochemical link between depression, anxiety, and stress, and that disturbances in neurochemical functioning may be associated with specific symptomatology, independent of psychiatric diagnosis.

Basal cortisol levels and cognitive deficits in human aging

A group of 19 healthy elderly subjects previously shown to differ in terms of their cortisol levels over a 4 year period were administered a neuropsychological test battery assessing memory, attention, and language. Correlational analyses performed on various corticosteroid measures showed that the slope of the change in cortisol levels over time predicted cognitive deficits in this elderly population. Aged subjects showing a significant increase in cortisol levels with years and with high current basal cortisol levels were impaired on tasks measuring explicit memory and selective attention when compared to aged subjects presenting either decreasing cortisol levels with years or increasing cortisol levels with moderate current basal cortisol levels. We further showed that subjects presenting a decrease in cortisol levels with years performed as well as young healthy subjects with regard to cognitive performance. Thus, impaired cognitive performance was associated with recent evidence of hypothalamic-pituitary-adrenal (HPA) dysregulation and elevated basal cortisol levels. These results are consistent with recent animal studies showing the existence of subpopulations of aged rats that differ in HPA activity and cognitive performance. Finally, the pattern of cognitive results related to the cortisol history of subjects is in agreement with a role played by the hippocampus in age-related HPA dysfunction and cognitive performance.

Biochemistry and pharmacology of reversible inhibitors of MAO-A agents: focus on moclobemide

Moclobemide, p-chloro-N-[morpholinoethyl]benzamide, is a prototype of RIMA (reversible inhibitor of MAO-A) agents. The compound possesses antidepressant efficacy that is comparable to that of tricyclic and polycyclic antidepressants. In humans, moclobemide is rapidly absorbed after a single oral administration and maximum concentration in plasma is reached within an hour. It is moderately to markedly bound to plasma proteins. MAO-A inhibition rises to 80% within two hours; the duration of MAO inhibition is usually between eight and ten hours. The activity of MAO is completely reestablished within 24 hours of the last dose, so that a quick switch to another antidepressant can be safely undertaken if clinical circumstances demand. RIMAs are potent inhibitors of MAO-A in the brain; they increase the free cytosolic concentrations of norepinephrine, serotonin and dopamine in neuronal cells and in synaptic vesicles. Extracellular concentrations of these monoamines also increase. In the case of moclobemide, increase in the level of serotonin is the most pronounced. Moclobemide administration also leads to increased monoamine receptor stimulation, reversal of reserpine induced behavioral effects, selective depression of REM sleep, down regulation of beta-adrenoceptors and increases in plasma prolactin and growth hormone levels. It reduces scopolamine-induced performance decrement and alcohol induced performance deficit which suggest a neuroprotective role. Tyramine potentiation with moclobemide and most other RIMA agents is negligible.

A comparison of the cardiac safety and therapeutic efficacy of trimipramine versus doxepin in geriatric depressed patients

OBJECTIVE

To compare the cardiac safety and therapeutic efficacy of trimipramine and doxepin.

DESIGN

A 1-week single-blind placebo period followed by a 5-week randomized double-blind parallel group clinical trial.

SETTING

Psychiatric out-patient clinic of a general hospital.

PATIENTS

37 young-elderly patients with a diagnosis of Major Depressive Episode (DSM-III criteria).

INTERVENTIONS

Placebo for 1 week, 2 weeks of titration with either drug in the dosage range of 75 mg/day up to a maximum of 200 mg/day.

MEASUREMENTS

We measured the psychiatric effects with the Hamilton Rating Scale for Depression, the Hamilton Anxiety Rating Scale, and the Clinical Global Impression Scale. Cardiovascular effects were assessed on 12-lead standard electrocardiograms plus 1-minute rhythm and high speed recordings; orthostatic (lying/standing) blood pressures were also taken. Physical exams, lab tests, cognitive functions (Buschke Selective Reminding Test, Hierarchic Dementia Scale, Word Fluency) and adverse reactions were also noted.

RESULTS

Both drugs were equally effective in relieving symptoms of depression and anxiety. The cardiovascular effects of both drugs were minimal. Trimipramine did lower blood pressure but this was without clinical significance. Three trimipramine patients and five doxepin patients developed occasional premature ventricular or atrial contractions. Of these, two trimipramine patients and one doxepin patient were among those with abnormal ECG's at entry. The doxepin patient was withdrawn from the study after 21 days of treatment when the PVC's became increasingly frequent.

CONCLUSIONS

Trimipramine and doxepin are equally safe and effective antidepressants in the young-elderly.

Levomepromazine receptor binding profile in human brain--implications for treatment-resistant schizophrenia

The receptor binding profile of levomepromazine (LMP) in human brain was compared with that of clozapine (CLOZ) and chlorpromazine (CPZ). LMP showed significantly greater binding affinity for both alpha-1 and serotonin-2 binding sites than either CLOZ or CPZ, and significantly greater binding to alpha-2 sites than CPZ. A potent pharmacological effect at these receptor sites may explain the beneficial effect of LMP on psychotic symptoms and akathisia in treatment-resistant schizophrenia recently described in 2 open studies. LMP requires further appraisal as a potentially useful neuroleptic in the management of treatment-resistant schizophrenia.

Glucocorticoid receptor gene expression is unaltered in hippocampal neurons in Alzheimer's disease

Excessive glucocorticoid levels increase the metabolic vulnerability of hippocampal neurons to a wide variety of insults. Since glucocorticoid hypersecretion occurs in Alzheimer's-type dementia it has been proposed that a primary reduction in hippocampal glucocorticoid receptor expression leads to failure of feedback, hypercortisolemia and hence further neuronal loss. However, we have recently found that lesions of the cholinergic innervation of the hippocampus--known to be severely affected in Alzheimer's disease--increase corticosteroid receptor gene expression in the rat hippocampus. We have now examined both glucocorticoid (GR) and mineralocorticoid (MR) receptor gene expression in individual neurons in human postmortem hippocampus, using in situ hybridization histochemistry in 5 patients with Alzheimer's disease (81 +/- 3 years) and 7 controls (81 +/- 7 years) without neurological disease. The distribution and intensity of MR and GR mRNA expression in the hippocampus of Alzheimer's disease were similar to that in control tissue, with high expression in dentate gyrus and CA2-4, but significantly lower expression in CA1. In a separate group of patients with Alzheimer's disease we found significantly increased 24 h integrated plasma cortisol levels (59% greater than age-matched controls) and reduced cortisol-binding globulin (21% lower). These data do not suggest a primary deficiency of biosynthesis of hippocampal corticosteroid receptors in Alzheimer's disease. The maintenance of hippocampal GR and MR gene expression, in the face of an increased glucocorticoid feedback signal, may reflect loss of the cholinergic innervation.

A 10-year follow-up study of tardive dyskinesia

In a 10-year follow-up study of 44 patients with tardive dyskinesia (TD), the majority (22 or 50%) had no change in their TD severity, 9 (20%) had an improvement and 13 (30%) had a worsening of their TD. Little difference was noted in those patients whose medication was decreased (n = 12) and those whose medication remained unchanged (n = 32). Of the women, 26% showed improvement as compared with 11% of the men. Also, patients whose TD improved had lower present neuroleptic dose than those whose TD worsened. These two factors should be studied in larger patient cohorts.

Is levomepromazine a useful drug in treatment-resistant schizophrenia?

Levomepromazine (LMP) unexpectedly improved 16 of 23 chronic treatment-resistant schizophrenic patients who were hospitalized in most cases for at least 2 years and who manifested positive symptoms, irritability and, in many cases, restlessness, hostility, uncooperativeness, poor concentration and aggressive behavior. Improvement led to discharge in 7 (6 to a foster home), placement on a waiting list for a foster home in 4 and improved behavior and autonomy in 5 patients. Five subjects developed seizures and 1 agranulocytosis. Whether improvement with LMP is caused by unique antischizophrenic properties or by diminished liability to induce side effects such as akathisia, a formal controlled study of LMP in treatment-resistant schizophrenia is merited.

Stereospecificity of the dopamine receptor mediating the growth hormone response to apomorphine in man. Short communication

The stereospecificity of the D-2 receptor mediating the growth hormone (GH) response to apomorphine (Apo) and the D-2 receptor regulating prolactin (PRL) secretion were investigated in 10 normal men by examining the effects of cis-flupenthixol (cis-Fx) and trans-flupenthixol (trans-Fx). cis-Fx (1 mg six hourly times four doses) antagonized the GH response to Apo HCl (0.5 mg sc) and increased basal serum PRL concentrations whereas the trans-isomer showed no effect. These findings (a) provide further evidence that the GH response to Apo is mediated by stimulating dopamine (DA) receptors, and, (b) demonstrate stereospecificity of the DA receptor mediating the GH response to Apo and the DA receptor regulating PRL secretion.

Localization of cholecystokinin binding sites in canine brain using quantitative autoradiography

1. CCK receptors have been characterized and localized in various mammalian species and significant species-specific differences in their distribution have been identified. In the present study, we report the first autoradiographic localization of CCK binding sites in the canine brain. 2. High densities of [125I]BH-CCK-8 binding sites were found in the cortex, cerebellum, hippocampus, caudate nucleus, olfactory bulb and nucleus accumbens. Moderate densities were present in the putamen, amygdala, and substantia gelatinosa. Low binding densities were observed in the globus pallidus, inferior colliculus, hypothalamus and thalamus. 3. Although the distribution profile of CCK binding sites in canine brain is similar to those previously reported in the rodent, primate and human brain, notable differences were observed in the hippocampus, cortex and cerebellum.

The effect of methyltestosterone on the growth hormone response to the dopamine receptor agonist, apomorphine

1. There is some evidence that androgens affect dopaminergic function in animals and man. We investigated the effect of methyltestosterone (MT) (30 mg po) on the growth hormone (GH) response to the dopamine (DA) receptor agonist, apomorphine (Apo) HC1 (0.5 mg sc), in 9 normal men. MT was given 2 hr before Apo. 2. The peak plasma MT concentration was present 1 hr after administration (19.9 +/- 19.5 ng/ml; X +/- SD); the concentration at 4 hr was 7.2 +/- 4.9 ng/ml. At the time of Apo administration, plasma MT varied from 6.0-24.1 ng/ml. 3. There was no significant effect of MT on Apo-GH secretion (interaction F(7,56) = 1.08; p = NS). The mean individual peak GH concentration after Apo alone was 20.2 +/- 11.9 (X +/- SD) vs 22.2 +/- 9.9 ng/ml when MT preceded Apo (p = NS). 4. These results suggest that exogenous androgens do not affect DA receptor function in males with normal androgenic function. Lack of effect due to an insufficient dose or duration of administration of MT cannot be excluded.

Factors in the development of severe forms of tardive dyskinesia

The authors evaluated 558 patients for tardive dyskinesia. They found that the prevalence of tardive dyskinesia was 34%. There were no differences between men and women in prevalence of tardive dyskinesia. However, severe tardive dyskinesia was found to occur more in male patients 40 years old or younger and in female patients 71 years old or older. Patients with mild tardive dyskinesia received more neuroleptics than did patients with moderate and severe forms. However, patients with moderate tardive dyskinesia had significantly more drug-free periods in their drug histories than did patients with mild tardive dyskinesia.

A controlled dose-ranging study of remoxipride and haloperidol in schizophrenia--a Canadian multicentre trial

The efficacy and side-effect profile for three dose ranges of remoxipride were compared with haloperidol in 242 schizophrenic inpatients in 13 centres. All patients were in a productive phase of schizophrenia according to DSM-III criteria. Relative efficacy of low dose (30-90 mg daily) vs middle dose (120-240 mg daily) vs high dose (300-600 mg daily) was compared with the standard dose of haloperidol (15-45 mg daily), as were the side effects. It was concluded that the therapeutic efficacy of remoxipride was comparable to that of haloperidol for acute episodes of schizophrenia; that the low dose range was significantly less effective than the higher ranges; that there was a clear advantage of remoxipride over haloperidol with respect to incidence and severity of extrapyramidal symptoms. The general safety profile of remoxipride as assessed from clinical chemistry, haematology, and cardiovascular variables suggests that remoxipride in the dose ranges studied can be used safely for the treatment of schizophrenic patients.

A dose-range finding study of zopiclone in insomniac patients

Sixty insomniac patients participated in a controlled double-blind parallel group study designed to investigate the dose-response relationship of zopiclone. Following 1 day of treatment with placebo, patients were randomly assigned to 1 of 6 groups and received treatment for 7 days with either placebo, or flurazepam 30 mg, or zopiclone, 3.75 mg, 7.5 mg, 11.25 mg or 15 mg. Four patients were dropped from the study; two from the placebo group due to ineffectiveness and one each in zopiclone 11.25 mg and 15 mg groups due to side-effects. Flurazepam 30 mg significantly improved sleep induction and maintenance by comparison to placebo and was indistinguishable from zopiclone 7.5 mg or higher. Results of a self-administered sleep questionnaire found a predominantly linear relationship between the dose of zopiclone administered and the degree of sleep improvement. The greatest increment in improvement was generally obtained with 3.5 mg and 7.5 mg of zopiclone, with some additional benefit occurring with zopiclone 11.25 mg. Clinicians' global impressions showed that the severity of illness clearly decreased in a dose related manner up to zopiclone 11.25 mg. Although zopiclone was well tolerated at 3.75 mg and 7.5 mg, an increase in side-effects occurred at 11.25 mg and 15 mg, which favours the use of 7.5 mg zopiclone as the optimum dose for most patients, although certain patients may benefit from a higher dose of the drug when well tolerated.

Effect of some peptides on dopaminergic function in man

Thyrotropin-releasing hormone (TRH) (200 micrograms iv) and 1-desamino-8-D-arginine vasopressin (DDAVP) (4 micrograms iv) antagonized the growth hormone (GH) response to apomorphine HCl (Apo) (0.5 mg sc) in 10 normal men. Apo had no effect on basal prolactin (PRL) levels but antagonized the PRL response to TRH. DDAVP plus Apo decreased PRL compared to placebo or DDAVP alone. These observations are compatible with (a) an inhibitory effect of TRH on hypothalamic and pituitary lactotrophe dopamine (DA) function (b) a facilitory effect of DDAVP on lactotrophe DA function and an inhibitory effect on hypothalamic DA function. Whether these are direct or indirect effects on DA mechanisms is unclear.

Neurochemical and receptor theories of depression

The neurochemical and receptor theories relate depression to deficient neurotransmission at critical sites in the brain. While this concept has generated a number of theories of depression over the years, the research findings do not fully support any single theory in its entirety. Several issues thus remain controversial or inconclusive. For instance, the monoamine deficit theory is supported by low urinary MHPG in some forms of bipolar, but not unipolar depression. Cerebrospinal fluid MHPG and 5-HIAA studies are inconclusive. Amine metabolite research is also limited in scope because the information derived pertains to pre-synaptic and synaptic events and ignores post-synaptic events. Receptor research, which includes study of both pre-and post-synaptic sites, suggests supersensitivity of Beta-adrenergic receptors in depression. But this research is criticized because it is mostly animal based. Also, the findings of low melatonin in depression contradict the supersensitivity-hypothesis. Abnormally low post-synaptic alpha-2 adrenoceptors is indicated by findings of an attenuated GH response to clonidine. But abnormality of pre-synaptic alpha-2 adrenoceptor functions has not been demonstrated conclusively. Recent findings in depression suggest a dysregulation in the dynamic and interactive relationship between neurotransmitters and receptors. Accordingly, a comprehensive view of the abnormalities of the various neurotransmitter systems in depression requires studies which investigate pre- and post-synaptic events simultaneously, preferably during illness and remission.

Effect of lithium and neuroleptic combination on lithium transport, blood pressure, and weight in bipolar patients

Patients treated with a combination of lithium (Li) and neuroleptics are reported to be at greater risk for toxicity. Previous findings suggested that treatment with a combination of Li and neuroleptics would increase the lithium ratio (LR) and intraerythrocyte Li levels. We studied 67 bipolar patients who were treated with Li alone (20 patients) or Li combined with haloperidol (17 patients), or Li combined with chlorpromazine (30 patients). Results revealed that the neuroleptic groups showed significantly lower LR and intracellular Li concentration as compared with those on Li alone. There was no significant difference in Li dosage among these three groups. No difference was found among these three groups with respect to mean blood pressure and weight. The number of hypertensive patients in the Li only group was twice as high as that in either of the two other groups, and the LR of the former was significantly higher than those of the latter groups.

Growth hormone response to apomorphine, a dopamine receptor agonist, in normal aging and in dementia of the Alzheimer type

The growth hormone (GH) response to the dopamine (DA) receptor agonist, apomorphine HCl (Apo) (0.5 mg SC) was studied in young and elderly normal subjects as well as in patients with dementia of the Alzheimer type (DAT) and controls matched for age, gender and Quetelet index. The GH response was significantly decreased in normal elderly men (mean age 67.3 years; N = 16) compared with young men (mean age 21.2 years; N = 12) and in elderly women (mean age 65.4 years; N = 9) compared with young women (mean age 25.5 years; N = 6) in the luteal phase but not in the early follicular phase. Young men had a significantly greater GH response than young women in either phase of the menstrual cycle. The decline in GH response with normal aging may be related to a decrease in sex steroid activity. There was no significant difference in GH response between DAT patients (N = 15) and paired controls. This suggests that hypothalamic D2 receptor function regulating GH secretion is not altered in DAT.