PSYCHOGERIATRICS 2005; 4: 133–135
Diagnostic tools for general practitioners and specialists Mathieu CECCALDI
Department of Neurology and Neuropsychology, University Hospital Centre (CHU) Timone, Marseille; and Neurophysiology and Neuropsychology Laboratory, INSERM EMI-U 99–26, Marseille, France. Correspondence: Professor Mathieu Ceccaldi, Hopital de la Timone, Service de Neurologie et de Neuropsychologie, Boulevard Jean Moulin, 13385 Marseille Cedex 05, France. Email:
[email protected]
Key words: dementia, diagnostic tool, general practitioner, specialist.
The diagnosis of dementia is a complex and evolving issue. An important challenge in this area is the establishment of methods providing an accurate diagnosis of Alzheimer’s disease (AD) in its preclinical phase, as we know that brain lesions develop several years before the disease becomes clinically evident. Another issue that is raised by epidemiological studies of the disease—for example, the Paquid study in France—is why one-third of the prevailing cases of dementia are not accurately diagnosed. This question naturally leads to a discussion of the approach used by specialists and general practitioners (GPs) in the diagnosis of dementia. In France, guidelines on dementia have been set up by Agence Nationale d’Accréditation et d’Evolution en Santé (ANAES). These guidelines specify diagnostic criteria for dementia (according to the Diagnostic and Statistical Manual of Mental Disorders, fourth edition (DSM-IV)) based on structured interviews of patients and their families, clinical examinations, recommended laboratory tests (systematic measures of thyroid-stimulating hormone (TSH), blood cell counts, glucose levels etc.) and brain imaging. The interviews should aim to actively collect information on the patient’s mental status: (i) changes in daily living activities (instrumental activities of daily living (IADL)); (ii) signs of depression (geriatric depression scale (GDS)); and (iii) behavioral abnormalities (neuropsychiatric inventory (NPI) and frontotemporal behavioral scale (FBS)). Cognitive functions are evaluated using the French version of the mini-mental
state examination (MMSE), which has been validated by the Groupe de Recherche et d’Evaluations Cognitives (GRECO). If there are further doubts about the patient’s mental status, tests should be repeated and if doubts persist, it is recommended that the patient be referred to specialists or to a memory clinic where a neuropsychological evaluation can be performed. These guidelines serve as a useful aid to physicians in their diagnosis of dementia, but they also implicitly suggest that all physicians have a similar approach. For specialists, the common goal is the diagnosis of a disease as early and accurately as possible, but they may have different conceptual backgrounds. Geriatricians may have a more global approach, with particular attention being paid to the general health status. The approach of psychiatrists to mental disorders may be more descriptive and phenomenologically and nosologically oriented. Neurologists are characterized by their clinical and anatomical approach, with the aim of defining the specific cognitive or non-cognitive dysfunction and identifying the affected neural system in order to identify the disease. These various approaches do not imply a disagreement among specialists. All specialists share common procedures, made up of combinations of ‘functional’ and ‘biological’ assessments. The functional assessment is based on a global clinical evaluation and psychometric tests. The use of global evaluation scales is based on the idea that an informant’s perception of an individual’s cognitive abilities in daily activities may be sensitive enough for the early 133
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detection of dementia. In a study conducted by Rubin et al.,1 a longitudinal examination of the clinical dementia rating (CDR) and psychometric performance was carried out in a group of elderly adults. The results show that although many subjects had a stable cognitive performance, as soon as a subtle cognitive decline was clinically detected through the CDR, a sudden deterioration in performance as measured by independently administered neuropsychometric tests was observed. The other aspect of the diagnostic approach of specialists is biological in nature: nutrition, vascular factors and the biology of the brain and proteins. Irrespective of the type of approach and the level of investigation, and taking into account that the prescription of anti-Alzheimer drugs should be preceded by a medical specialist’s assessment, the first contribution of a specialist is a diagnosis. GPs hold a key position on the primary care level, but they do not diagnose AD in routine practice. Their knowledge of dementia and diagnostic procedures has been shown to vary considerably. There is a low rate of success among GPs in the diagnosis of dementia and mental disorders, with underdiagnosis of degenerative disorders and overdiagnosis of ‘disturbed cerebral perfusion’ and vascular dementia. A study has been conducted to evaluate the accuracy of diagnosis of a representative sample of 64 GPs in comparison with the diagnosis provided by an outpatient memory clinic.2 The results show that 29% (n = 9) of the patients who were diagnosed by the GP (n = 31) as not having dementia were diagnosed with dementia by the specialists. However, 17% (n = 9) of the patients who were suspected by the GP of having dementia and referred to the specialists did not have the diagnosis confirmed by the specialists. Furthermore, no agreement was reached concerning the types of dementia diagnosed. These results show that memory clinics make a substantial contribution, especially regarding the identification of the type of dementia. The challenge is to define the aim of the GP’s approach to the diagnosis of dementia. This could involve diagnosis of the disease, which is the specialists’ approach; detection of cognitive decline according to the ‘case-finding’ method; or appropriate selection of patients for specialized referral. The IMAGINE study,3 proposed by the EISAI laboratory (Paris, France) and coordinated by Dr Duveau, is a survey of GP practice. A questionnaire was sent to 134
2750 GPs and the answers were analyzed. Preliminary results show that 62.8% of GPs use specific tools for diagnosis. The MMSE is used by 72.3% of GPs, while other tools cited are used by less than 15% of them. A similar study, conducted by Professor Michel Bourgeois in the Department of General Practice at the University of Marseille in France, reveals that only 50% of the GPs (who were selected because they were responsible for care institutions for the elderly) declared that they use the MMSE. The reasons they generally gave for not using the MMSE were that they did not have enough time, that the technique was artificial and too scientific and that the testing affected their dialogue with patients. Gert Almind, from the Institute of Social Medicine in Copenhagen, wrote: ‘Can we test memory like we test blood pressure, or must the test be invisible?’ This question stresses the difficulties GPs have in implementing the use of psychometric testing in their daily practice. In France, the IMAGINE study should lead to the establishment of a centre which monitors the diagnosis of AD in general practice. This centre will be promoted by the EISAI laboratory and supervised by Professor Dartigues. In my opinion, the recommendation of diagnostic tools for GPs needs to take into account the respective features and constraints of specialist and general practice. Specialists generally do not know the patients, their families or the context. Their intervention is essentially transversal and the objectives of consultation are definite and explicit. The compliance of patients and their families with the procedures of specialists is usually assured. In contrast, the GP’s intervention is longitudinal. They have known their patients and their patients’ families for a long time, and are aware of the context and evolution of their patients’ lives. Consultation has a very wide spectrum of goals, most of them being implicit. Thus, general practice tends to be subjected to criticism by patients. To conclude, the challenge is to find an alternative way for GPs to deal with the diagnosis of dementia which does not impose the specialist’s approach, but takes into account the fact that GPs are the ones most familiar with their patients’ backgrounds.
REFERENCES 1 Rubin EH, Storandt M, Miller JP et al. A prospective study of cognitive function and onset of dementia in cognitively healthy elders. Arch Neurol 1998; 55: 395–401.
Diagnostic tools for Alzheimer’s disease 2 Van Hout H, Vernooij-Dassen M, Poels P, Hoefnagels W, Grol R. Are general practitioners able to accurately diagnose dementia and identify Alzheimer’s disease? A comparison with an outpatient memory clinic. Br J General Pract 2000; 50: 311–312.
3 Dartigues JF. Information sur la maladie d’Alzheimer en medecine generale et intervention neurocognitive par JF Dartigues: 7eme reunion francophone sur la maladie d’Alzheimer et les syndromes apparentes. 7–10 Oct 2003, Paris. (In French.)
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