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H Merskey

Publications and source records attributed to H Merskey.

At least 37 records · Page 2Linked to original sources
PubMed1998

Fallacies in the pathological confirmation of the diagnosis of Alzheimer's disease.

OBJECTIVE: Necropsy confirmed clinical diagnostic accuracy for Alzheimer's disease is claimed to exceed 90%. This figure contains two fallacies; it includes cases in which Alzheimer's disease exists with other diseases affecting cognition and the studies that report these figures excluded cases without necropsy (verification bias). The effect of these errors is estimated. METHODS: Data were taken from the University of Western Ontario Dementia Study, a registry of dementia cases with clinical and psychometric follow up to necropsy based in a university memory disorders clinic with secondary and tertiary referrals. Data were available on 307 patients; 200 (65%) had clinically diagnosed Alzheimer's disease, 12 (4%) vascular dementia, 47 (15%) mixed dementia, and 48 (16%) had other diagnoses. One hundred and ninety two of 307 cases (63%) died and 122 of 192 fatalities (64%) had necropsies. The pathological material was interpreted in two ways, allowing and disallowing coexistent disease in making a diagnosis of Alzheimer's disease. In cases without necropsy, progressive cognitive loss was used as a marker for degenerative dementia. The outcome measures of interest were the positive predictive value of a clinical diagnosis of Alzheimer's disease allowing and disallowing coexistent diseases and with and without correction for cases that were not necropsied. RESULTS: The clinical diagnoses differed significantly between the population who died and those who did not. In cases without necropsy, 22% had no dementia on follow up, concentrated in early cases and men, showing considerable scope for verification bias. The positive predictive value of a diagnosis of Alzheimer's disease was 81% including coexistent diseases, falling to 44% when limited to pure cases. Combined, these factors reduce the positive predictive value to 38% for pure Alzheimer's disease. CONCLUSIONS: Correction for dual pathology and verification bias halves the positive predictive value of the clinical diagnosis of Alzheimer's disease. Data derived from necropsy studies cannot be extrapolated to the whole population. This has important implications including uncertainty about diagnosis and prognosis and a dilution effect in therapeutic trials in Alzheimer's disease.

Alzheimer Disease↗
PubMed1998

Factors affecting the age of onset and rate of progression of Alzheimer's disease.

OBJECTIVES: To assess the role of cerebrovascular disease, sex, education, occupation, year of birth, leukoaraiosis, congophilic angiopathy, family history, and other demographic factors on the reported age of onset and rate of progression of Alzheimer's disease. METHODS: Analysis of data from the University of Western Ontario Dementia Study, a prospective longitudinal study of dementia patients with clinical and 6 monthly psychometric follow up to postmortem based in a university memory disorders clinic with secondary and tertiary referrals. There were 172 patients with dementia. The main outcome measures were the reported age of onset of cognitive decline as described by the family (available in 168) and rate of progression as measured during the linear phase of the extended scale for dementia, which could be calculated in 66. The cases subdivided into 49 cases of definite Alzheimer's disease without infarcts, 25 cases of otherwise definite Alzheimer's disease with infarcts, 79 cases of probable Alzheimer's disease without infarcts, and 19 such cases with infarcts. RESULTS: The age of onset was not influenced by the rate of progression, the presence of cerebral infarcts, or congophilic angiopathy. Educational level, occupational level, sex, family history, year of birth, reported age of onset, severity at entry, an ischaemic score, and the presence of leukoariosis, affected neither age of onset nor the rate of progression. An earlier year of birth had a major effect and higher education had a minor effect on earlier age of onset. The earlier the year of birth, the lower the educational level and the greater the accrual of cerebral infarcts. CONCLUSIONS: Contrary to series without pathological verification, age of onset in this study was not affected by occupation. Education had a modest effect on earlier reported onset, probably reflecting earlier recognition. As birth year has a strong effect on educational level and the occurrence of cerebral infarcts, this must be taken into account when analysing for risk factors for Alzheimer's disease.

Adult↗
PubMed1998

The relationship of catatonia symptoms to symptoms of schizophrenia.

OBJECTIVE: To evaluate the relationships of symptoms of catatonic schizophrenia to 77 symptoms relevant for diagnosing schizophrenia and to socioanamnestic variables. METHOD: Data from a sample of 112 Canadian patients diagnosed with schizophrenia according to the Diagnostic and Statistical Manual of Mental Disorders (DSM-III) were evaluated via phi correlation coefficients. RESULTS: Forty-five (40.2%) of our 112 patients had catatonic symptoms, either at the time of this study or in the past. However, only weak correlations (phi < 0.31) to other symptoms relevant for diagnosing schizophrenia were found, and no significant correlations to socioanamnestic variables were found. CONCLUSION: Symptoms of catatonia appear to be independent of the key symptoms of schizophrenia.

Adult↗
PubMed1997

Comparative evolution of Alzheimer disease, vascular dementia, and mixed dementia.

OBJECTIVE: To compare the evolution of Alzheimer disease (AD), vascular dementia (VaD), and mixed dementia by cognitive domain. SETTING: The University of Western Ontario Dementia Study, which is a registry of cases of dementia seen for secondary and tertiary assessment in a university memory disorders clinica with extensive follow-up data and histopathological confirmation of clinical diagnoses. PATIENTS: One hundred twenty-nine patients with definite or probable AD, 12 patients with definite or probable VaD, and 36 patients with definite or probable mixed dementia. METHODS: Patients were grouped as having an early, moderate, or advanced stage of disease according to the extended scale for dementia (ESD). The ESD was subdivided into cognitive domains, and the domain scores were compared for each stage of disease by diagnostic category with the use of a 2-way analysis of variance with repeated measures. RESULTS: As expected, the scores in all domains decreased significantly with increasing severity. There was a significant difference in the decline in memory among the diagnostic groups (P = .02) that was mostly attributable to the difference between AD and mixed dementia (P = .03), with the difference between AD and VaD only approaching significance (P = .06). There was a similar finding for praxis. The interaction between diagnosis (AD and VaD) and severity was significant only for memory (P = .02), showing a less severe memory deficit at onset but a proportionately more rapid progression in VaD and arithmetic ability (AD and mixed dementia [P = .03]). CONCLUSIONS: Alzheimer disease, VaD, and mixed dementia evolve similarly as assessed using cognitive domains obtained by subdivision of the ESD in a patient population derived from a memory clinic and by analyzing VaD as a single entity. Only memory impairment evolves differently between AD and VaD, with this depending on the severity. Memory is more severely impaired in the early stage of AD; however, with increasing severity of dementia, memory impairment in VaD accelerates and catches up with AD at the level of moderate impairment. The differences between AD and mixed dementia are greater than those between mixed dementia and VaD, suggesting an important role for the ischemic component of mixed dementia. Simple neuropsychological tools (eg, the ESD) may be incapable of distinguishing between AD and VaD, and more focused instruments may be required. Inherent bias in case selection may prevent extrapolation of these results to VaD in general, but the neuropsychological criteria for VaD may need to vary, depending on the severity.

Alzheimer Disease↗
PubMed1997

Pharmacological approaches other than opioids in chronic non-cancer pain management.

Many pains are controlled by non-addictive procedures ranging from exercise to a variety of analgesic medications. Some pains are controlled by analgesic drugs, but at the cost of intolerable side effects. This is true both for non-steroidal anti-inflammatory drugs and opioids. The worst pains are most often controlled by opioids, but problems of tolerance and addiction limit these successes. This contribution provides a statement on non-addictive, non-opioid drugs which help to control pain. Just as these vary in their success, so they vary also in the strength of the scientific evidence which supports their use. The groups of drugs to be considered can be evaluated in three respects; evidence of analgesic effect in controlled trials; evidence of side-effects compared with control substances and with standard experience; evidence of usefulness in clinical practice. The latter which is the most important for practice often has the least scientific proof. Six main classes of drugs are recognized which provide analgesic effects, other than opioids. 1) Non-steroidal anti-inflammatory drugs are widely accepted as analgesics on the basis of animal studies, numerous controlled investigations and clinical practice. Acetaminophene may not be anti-inflammatory, but is recognized as an effective analgesic which in many other respects resembles the above. 2) Muscle relaxants, e.g. cyclobenzaprine or baclofen have varied actions, but often provide some relief of pain. 3) Antidepressants may be analgesic if they relieve depression which is giving rise to pain. This applies to all anti-depressants. Some antidepressants have been shown to be analgesic in the absence of depression. The best accredited of these is amitriptyline. Antidepressants too have significant side effects. A serotoninergic hypothesis is insufficient to explain the actions of antidepressants in relieving pain in the absence of depression. 4) Phenothiazine neuroleptics (and possibly some others) may be analgesic. Drugs reported to be analgesic include chlorpromazine, fluphenazine, perphenazine, trifluoperazine, methotrimeprazine (levomepromazine) among others. Haloperidol has also been utilized. Well controlled evidence exists with the use of methotrimeprazine (levomepromazine) used as an injection. The analgesic effect of oral neuroleptics is less well established and mostly depends upon clinical observation, withdrawal and re-challenge. 5) Anticonvulsants. 6) Other drugs. Non-steroidal anti-inflammatory drugs and some muscle relaxants, e.g. cyclobenzaprine are best used in the short term. The gastrointestinal side effects of non-steroidal anti-inflammatory drugs have been quite troublesome and over 2% of patients followed over five years are at risk of developing peptic ulceration from such medication. Cyclobenzaprine is best used in short term treatment, but may be used intermittently for chronic pain. Antidepressants, neuroleptics, anticonvulsants and some other drugs can be used long term. Topical analgesic agents may also be used.

Analgesics↗
PubMed1997

The prevalence of current major depression and dysthymia in a Norwegian general practice.

Existing studies suggest that depression is underdiagnosed and undertreated in general practice, and that the known prevalence of this mood disorder in a primary care population may represent only the "tip of the iceberg'. A total of 100 consecutive patients in an average Norwegian general practice were tested, of whom 31 patients were diagnosed as having a depressive illness in this study; 28 patients were diagnosed as having current major depression and three as having dysthymia. In total, 21 of the 28 patients with current major depression presented with other symptoms as their major complaints at the consultation in which they were tested. Twelve of these 21 patients had some kind of pain problem.

Adolescent↗
PubMed1996

Randomised trial of oral morphine for chronic non-cancer pain.

BACKGROUND: The use of opioid analgesics for chronic non-cancer pain is controversial. Some surveys report good pain relief and improvement in performance while others suggest a poor outcome with a propensity to psychological dependence or addiction. METHODS: We undertook a randomised double-blind crossover study to test the hypothesis that oral morphine relieves pain and improves the quality of life in patients with chronic regional pain of soft tissue or musculoskeletal origin who have not responded to codeine, anti-inflammatory agents, and antidepressants. Morphine was administered as a sustained-release preparation in doses up to 60 mg twice daily and compared with benztropine (active placebo) in doses up to 1 mg twice daily over three-week titration, six-week evaluation, and two-week washout phases. Pain intensity, pain relief, and drug liking were rated weekly and psychological features, functional status, and cognition were assessed at baseline and at the end of each evaluation phase. FINDINGS: After dose titration in the 46 patients who completed the study, the mean daily doses of drugs were morphine 83.5 mg and benztropine 1.7 mg. On visual analogue scales, the morphine group showed a reduction in pain intensity relative to placebo in period I (p = 0.01) and this group also fared better in a crossover analysis of the sum of pain intensity differences from baseline (p = 0.02). No other significant differences were detected. INTERPRETATION: In patients with treatment-resistant chronic regional pain of soft-tissue or musculoskeletal origin, nine weeks of oral morphine in doses up to 120 mg daily may confer analgesic benefit with a low risk of addiction but is unlikely to yield psychological or functional improvement.

Administration, Oral↗
PubMed1996

Psychological medicine, pain, and musculoskeletal disorders.

There is a two-way relationship between pain and psychological illness. Pain may be produced by psychological states and may cause psychological disturbances. For these reasons, pain and psychiatric problems are often associated. Selection is also highly important in influencing the population of all hospital clinics dealing with chronic nonfatal illness. Patients from this group show increased emotional difficulty, which in the past has been misunderstood as evidence of a psychological etiology.

Anxiety↗
PubMed1996

Ethical issues in the search for repressed memories.

Currently, concepts of repression and dissociation are in flux. It has been pointed out that there is no scientific evidence for the occurrence of repression and that the whole notion is anecdotal. Dissociation, which is offered as an alternative to repression, cannot logically be held to operate without a motive force, as Freud argued, or a weakness of the organism, as Janet proposed. The concepts have been applied particularly to the idea that early childhood experience could be repressed but recovered many years later. This claim is at variance with established knowledge concerning human memory. Practices of subtle and overt suggestion, employed in recovered-memory treatments, give rise to a false-memory syndrome in which individuals, who have undergone various levels of suggestion, accuse their parents and others of childhood sexual abuse. The common phenomenon of childhood sexual abuse is contaminated by many cases that may be regarded on strong grounds as being false and have been retracted in more than 1,000 instances. Repressed-memory (RM) treatment is also at variance with traditional psychotherapy, which does not encourage confrontation on the basis of uncorroborated information; moreover, many cases of RM therapy seem to result in deterioration. Unlike traditional psychotherapy, some RM practitioners strongly encourage patients to hate individuals in their family circle. The consequences of these developments, the need for informed consent, and the development of legislative initiatives to challenge RM therapy are noted. The impact of these therapies and proposed legislation upon regular psychotherapy and psychiatry is outlined.

Child↗
PubMed1995

Patterns of deterioration in senile dementia of the Alzheimer type.

OBJECTIVE: To determine rates of decline in Alzheimer's disease. DESIGN: A longitudinal review of patients diagnosed as having dementia during life, tested serially with the Extended Scale for Dementia, and confirmed by autopsy as having Alzheimer's disease. SUBJECTS AND SETTING: Twenty-nine dead patients with Alzheimer's disease from the participants in the University of Western Ontario Dementia Study Project, confirmed at autopsy as having Alzheimer's disease. METHODS: Analysis of the Extended Scale for Dementia data according to a trilinear model. FINDINGS: In the middle phase of the trilinear model, there was a mean annual change of 13% (range, 2.5% to 51.7%). CONCLUSIONS: It is likely that the common method of averaging a group of different individual scores from the initial and middle phases of observation of Alzheimer's disease collapses together individuals at different stages of the disorder, some of whom are in the initial plateau phase and whose conditions are not declining rapidly. The trilinear model of decline avoids this difficulty and the present study provides postmortem confirmed figures on rate of change.

Aged↗