Mental decline in the elderly: pharmacotherapy (ergot alkaloids versus papaverine)

Hydergine for dementia

BACKGROUND

Currently hydergine is used almost exclusively for treating patients with either dementia, or 'age-related' cognitive symptoms. Since the early eighties there have been over a dozen more clinical trials, yet hydergine's efficacy remains uncertain. Although previous reviews offer generally favorable support for hydergine's efficacy, they were, however, limited by a bias with respect to the particular clinical studies chosen (eg, the inclusion of case reports, and uncontrolled trials), and by authors' impressionistic assessments of results. Not surprisingly, there has been a lack of consensus among reviewers with regard to the efficacy of hydergine. In 1994, a meta-analysis was published by the present reviewers who reported that overall, hydergine was more effective than placebo. However they also observed that the statistical evidence for efficacy in 'possible or probable Alzheimer's disease' patients was so modest that one additional statistically non-significant trial would have reduced the results to non significance.

OBJECTIVES

Because of uncertainty surrounding the efficacy of hydergine, the goals of this overview were to assess its overall effect in patients with possible dementia, and to investigate potential moderators of an effect.

SEARCH STRATEGY

The Cochrane Dementia Group Register of Clinical Trials was searched using the terms 'hydergine', 'ergoloids,' 'ergoloid mesylates,' 'dihydroergocristine,' 'dihydroergocryptine,' 'dihydroergotoxine,' and 'dihydroergocornine. MEDLINE, EMBASE, and two proprietary databases were searched also. Published reviews were inspected for further sources.

SELECTION CRITERIA

Trials to be included must be randomized, double-blind, parallel-group, and unconfounded comparisons of hydergine with placebo for a treatment duration of greater than 1 week in subjects with dementia or symptoms consistent with dementia.

DATA COLLECTION AND ANALYSIS

Data were extracted independently by the reviewers, pooled where appropriate and possible, and the pooled odds ratios (95%CI) or the average differences (95%CI) were estimated. Where possible, intention-to-treat data were used. Outcomes of interest included clinical global impressions of change and comprehensive rating scales. Potential moderating variables of a treatment effect included: inpatient/outpatient status, trial duration, age, sex, medication dose, publication year, and diagnostic grouping.

MAIN RESULTS

There were a total of nineteen trials that met inclusion criteria and that had data sufficient for analysis. Thirteen trials reported sufficient information to use a global rating of improvement and nine trials provided information on a comprehensive rating scale. Three trials provided both outcome measures. It was not possible to use many of the published results in a combined analysis owing to the lack of sufficient data to perform statistical analyses. For the twelve trials that used global ratings, there was a significant effect favoring hydergine (OR 3.78, 95%CI, 2.72-5.27). For the nine trials that used comprehensive ratings, there was a significant mean difference favoring hydergine (WMD 0.96, 95%CI, 0. 54-1.37). Hydergine was well tolerated in these trials, with 78% of randomized subjects available for data analyses. Greater effect sizes on global ratings were associated with younger age, and possibly higher dose, although most of the subgroup analyses were statistically insignificant.

REVIEWER'S CONCLUSIONS

As in an earlier systematic review, we found hydergine to show significant treatment effects when assessed by either global ratings or comprehensive rating scales (based here on a smaller set of trials than in the earlier published systematic review because trials were required to have data that could conform with MetaView, the Cochrane Collaboration statistics software). The small number of trials available for analysis, however, limited the ability of subgroup analyses to identify statistically significant modera

Effects of chronic codergocrine mesylate administration on the brain somatostatinergic system in aged rats

Codergocrine mesylate (dihydroergotoxine; DHET), which is an ergot derivative, has been reported to counteract some age-induced impairments in brain function, but the mechanism of these effects is not known. We examined the effect of chronic DHET administration on the somatostatinergic system in the brains of aged rats. Intraperitoneal injections of DHET (1 mg/kg per day) or of vehicle were given to aged rats for 14 days, and resulted in a significant increase in somatostatin (SOM) receptor binding in all six brain regions examined except the hindbrain. DHET had no effect on SOM receptor binding in the brains of young-adult rats. However, the SOM concentration in aged rats was nearly identical to that in young-adult rats and the SOM concentration in different brain areas did not change after chronic administration of DHET. Thus, the present results suggest that chronic administration of DHET can ameliorate at least one of the age-induced impairments of brain somatostatinergic function.

Dose-response studies with co-dergocrine mesylate under hypoxia utilizing EEG mapping and psychometry

In a double-blind, placebo-controlled trial, human brain function and mental performance were studied under two different degrees of hypoxia after administration of two different doses (6 mg and 9 mg) of co-dergocrine mesylate (CDM) utilizing blood gas analysis, EEG mapping and psychometry. Hypoxic hypoxidosis (i.e. impairment of cerebral metabolism due to hypoxia) was experimentally induced by a fixed gas combination of 9.8% oxygen (O2) and 90.2% nitrogen (N2) (found in 6000 m altitude), and of 8.6% O2, 91.4% N2 (found in 7000 m altitude), which was inhaled for 23 min under normobaric conditions by 18 healthy volunteers. They received randomized after an adaptation session placebo, 6 mg and 9 mg co-dergocrine mesylate (CDM). Evaluation of blood gases, brain mapping and psychometry was carried out at 0, 2, 4, 6, 8 h after oral drug administration. Blood gas analysis demonstrated a drop in PO2 to 42 and 32 mm Hg 23 min after inhalation of the 9.8% and 8.6% gas mixture, respectively, PCO2 decreased to 32 and 31 mm Hg, pH increased to 7.46 and 7.47 and base excess increased to 0.50 and 0.90 nmol/l, respectively. EEG mapping demonstrated an increase in delta and decrease of alpha power and a slowing of the centroid over almost the whole brain. 6 mg and slightly less so 9 mg CDM attenuated this deterioration of vigilance (i.e. dynamic state of the neuronal network determining adaptive behavior). At the behavioral level, moderate hypoxia induced a deterioration of noopsychic performance, which was mitigated by 6 mg, but not by 9 mg CDM. A deepening of the hypoxia resulted in a loss of these brain protective effects of both doses. Decrement of the thymopsyche increased after both doses in the moderate hypoxic condition, while under marked hypoxia 6 mg CDM attenuated and 9 mg aggravated this deterioration. Time-wise, brain protective effects reached the level of statistical difference between the 2nd and the 6th hour. Somatic complaints like feeling dazed, giddiness and headache were mitigated dose dependently by CDM in the moderate, but not in the marked hypoxic hypoxidosis.

The safety and lack of efficacy of vinpocetine in Alzheimer's disease

Fifteen Alzheimer patients were treated with increasing doses of vinpocetine (30, 45, and 60 mg per day) in an open-label pilot trial during a one-year period. Patients were assessed seven times both on and off drug with: the Buschke Selective Reminding Task, a letter fluency test, a category fluency test, the Boston Naming Test, a cognitive capacity screening examination, and a clinical global impression. Vinpocetine failed to improve cognition on psychometric testing or overall functioning, as measured by the clinical global impression, at any dose tested. Patients showed significant decline in most measures during the course of the study, at the same rate as a matched control group, consistent with progressive dementia. There were no significant side effects from drug therapy. We conclude that vinpocetine is ineffective in improving cognitive deficits and does not slow the rate of decline in individuals with Alzheimer's disease.

Effects of intravenous high dose co-dergocrine mesylate ('Hydergine') in elderly patients with severe multi-infarct dementia: a double-blind, placebo-controlled trial

A double-blind, placebo-controlled trial was carried out in 40 patients affected by multi-infarct dementia to see if a daily intravenous infusion of 3 mg co-dergocrine mesylate ('Hydergine') over 14 days would improve severely deteriorated elderly patients and shorten the latent period (3 months) which is observed when the drug is given orally. All the patients had severe mental impairment, psychological deficit or altered consciousness. A Hachinski score of 7 or more, and a cumulative score of at least 12 points on SCAG scale Items 1, 2 and 4 (anxiety/depression) and/or Items 5, 6 and 8 (alertness/confusion) were required for admission. After 1 week of intravenous infusion of placebo, patients were randomly allocated to treatment with co-dergocrine mesylate or placebo, from Day 1 to Day 14. The solutions were infused over a period of 2 hours. During the follow-up period from Day 15 to Day 21, the patients did not receive any treatment. Thirty-six patients (17 on co-dergocrine mesylate, 19 on placebo) completed the study. The results, as rated on the SCAG scale, indicated significant improvements, in favour of co-dergocrine mesylate, in cognitive dysfunction, mood depression, withdrawal and overall impression. Furthermore, the factor fatigue on the Nowlis scale and clinical global assessments by physicians also showed significant advantages of the co-dergocrine mesylate group over placebo. Nine out of 17 co-dergocrine mesylate patients complained of side-effects, usually experienced during infusion; they consisted mainly of nausea (6 patients), gastric discomfort (2 patients), and tremor, nasal congestion, flushing, hypotension and hypertension (1 patient each). Despite the appearance of side-effects, general tolerability was rated as 'good' by both physicians and patients. It is concluded, therefore, that intravenous high dose co-dergocrine mesylate treatment has a fast and clinically relevant effect on the key clinical symptoms of multi-infarct dementia.

Pharmacotherapy of memory loss in the geriatric patient

Memory loss is a common problem with advancing age and a prominent symptom in dementia. Categories of drugs used to reverse memory loss and enhance recall are reviewed. Positive results have been observed with cholinergic drugs, acetylcholine precursors, and the newer category of cerebral metabolic enhancers and nootropic agents. Combinations of these classes of drugs are being tried in current research.

Double-blind clinical and psychologic study of ergoloid mesylates (Hydergine) in subjects with senile mental deterioration

A double-blind study of 24 weeks' duration was conducted to investigate the effects of ergoloid mesylates (Hydergine) on symptoms of senile mental deterioration. Fifty-eight residents of old people's homes were included in the trial. Thirty were treated with ergoloid mesylates and 28 with placebo, and the effects of treatment were determined by means of medical and psychological examinations. On the Sandoz Clinical Assessment Geriatric Scale, the group receiving ergoloid mesylates showed significant improvement in all items. The group receiving placebo showed slight deterioration. Psychological examination showed that no changes were observed for either group in quantitative psychometric test results, although qualitative aspects of performance such as attention and concentration did improve. There was a close correlation between improved cognitive function scores on the SCAG and improved evaluations of behavior during the psychological examinations. There were marked individual differences in the degrees of improvement.

Chronic dihydroergotoxine administration sets on receptors for enkephalin and thyrotropin releasing hormone in the aged-rat brain

Dihydroergotoxine (DHET) is comprised of equal part of the mesylates of dihydroergocristine, dihydroergocornine and dihydroergocryptine. In the standard radioreceptor assays, DHET components displaced the CNS-receptor binding of [3H]-enkephalin (ENK) and [3H]thyrotropin releasing hormone (TRH). The inhibitory effect of DHET on ENK binding was competitive, and an allosteric effect seems to be involved in the DHET inhibition of TRH binding to its receptor. Intraperitoneal injections of DHET (1 mg/kg/day) to aged rats for 14 days resulted in a significant increase of ENK and TRH binding in the cerebral cortex. Scatchard plots of saturation experiments indicate that the increase of ENK binding is due to the increased affinity of the binding sites, and the increase of TRH binding reflects an increase in numbers of binding sites. The results suggest that the therapeutic efficacy of DHET is derived initially from its effects on the ENK and TRH receptors especially in the cerebral cortex, which in turn influence the function of monoaminergic neurons.

Cyclandelate in the treatment of senile mental changes: a double-blind evaluation

The treatment of cerebrovascular insufficiency and its many symptoms in the ever-increasing numbers of the aged, is of major concern to physicians engaged in such care. Despite past skepticism as to the degree of efficacy of cerebral vasodilators, there is renewed interest in this form of therapy. Our investigation was designed to assess the effectiveness of cyclandelate, under strict double-blind conditions, in 58 geriatric patients. The cyclandelate and placebo groups (32 and 26 patients respectively) received either 1,600 mg/day of cyclandelate in fractional doses, or identical-appearing placebo capsules--over a period of 12 weeks. During the initial examination and every four weeks thereafter, patients were assessed for possible changes in vital signs and for evidence of adverse reactions. In addition, the Sandoz Clinical Assessment-Geriatric (SCAG) and the Nurses Observation Scale for Inpatient Evaluation (NOSIE) were completed, with particular attention to symptom clusters. A final global assessment was made in which the physician rated patients according to their overall clinical condition. The results of our study and analysis indicate that cyclandelate is a safe and effective agent for treating certain symptoms of senility in properly selected patients, provided the therapy is carried on for at least eight weeks and, if indicated, for a longer period. Clinical evidence suggests that the prudent use of this drug may definitely delay deterioration.

An ergot alkaloid preparation (Hydergine) in the treatment of dementia: critical review of the clinical literature

A critical review is presented of 12 clinical trials with Hydergine (a hydrogenated ergot alkaloid preparation) in the treatment of dementia. Qualitative and quantitative comparisons of improvement in symptoms showed that Hydergine consistently produced statistically significant (p less than or equal to 0.05) improvement in 13 symptoms associated with dementia. However, because of the small magnitude of the improvement and the absence of indications of long-term benefit, Hydergine would seem to be of minor value in dementia therapy. Further research with better methodology and design might lead to a different conclusion.