Memory performance,self-reported memory loss and depressive symptoms in attenders at a GP-referral and a self-referral memory clinic

Reports of declining memory are common with increasing age. Sometimes these are corroborated by poor memory test performance, but often they appear to be more closely related to depressive symptomatology. As pharmacological treatments emerge for improving cognition in the elderly, understanding the aetiology of memory complaints will become increasingly important. This article compares memory performance, reports of memory loss and depressive symptoms in attenders at a GP-referral and a self-referral memory clinic, with age- and sex-matched community controls. The GP-referred patients were older, had lower MMSE scores and had levels of memory complaint and depression between the control and self-referred subjects. The self-referrers had cognitive test performance similar to community controls but complained more of memory loss, were more depressed and more frequently reported a past history of treated depression. Self-presentation of memory complaint appears to be more closely related to affective and possibly personality factors than memory test performance.     

Demographic and clinical features of patients attending a memory clinic

Basic demographic and clinical features of the first 418 patients assessed at the Maudsley Memory Clinic are reported. Alzheimer's disease was the most frequent diagnosis (57%), followed by a group of patients complaining of memory problems but with no obvious neuropsychiatric diagnosis (24%). The latter were more likely to be younger unmarried self-referred women living alone and with a frequent family history of dementia. The routine use of extensive laboratory investigations in memory clinics is not recommended, considering the meagre number of subjects suffering from reversible conditions identified in our clinic. The Maudsley Memory Clinic has proved to be a popular centre for the assessment and diagnosis of patients with memory complaints and has provided a useful source of subjects for research into memory-associated disorders. The role of memory clinics in the new financial climate in the National Health Service remains to be determined.     

Age-associated memory impairment: Diagnostic and treatment issues

There has been an enormous increase in research to identify potential pharmacological treatments for cognitive impairment in elderly people. Currently, well over 150 such compounds are under development by the pharmaceutical industry. However, among those who are potential targets for such treatment are many who suffer from relatively mild disorder, where the distinction from both dementia and ‘normality’ is not clear. These people include those described as suffering from benign senescent forgetfulness and age-associated memory impairment. This article discusses principles of diagnosis and treatment in this area with particular reference to age-associated memory impairment. For ethical, practical and economic reasons it is essential that these issues are examined thoroughly before any apparent breakthrough in therapy.     

Depression and anxiety in memory clinic attenders and their carers: implications for evaluating the effectiveness of cognitive rehabilitation interventions

BACKGROUND: The potential of cognitive rehabilitation (CR) for people who have a diagnosis of Alzheimer's disease (AD) is increasingly being recognised. It has been suggested, however, that interventions targeting memory functioning in AD have negative effects on the well-being of participants and carers in terms of mood and perceived strain. While some 'memory training' studies do report an increase in self-report scores on scales assessing these variables, it is not clear whether the changes are attributable to the intervention. There is some overlap between CR and 'memory training', but CR is a much more individualised approach, and therefore CR intervention studies often adopt within-subjects or single case experimental designs, for which relevant comparison data are required. METHOD: Participant and carer depression and anxiety, and carer strain, were assessed at initial attendance and again by postal survey 6 months later in a consecutive series of 94 Memory Clinic referrals who received standard treatment but no specialised CR interventions. RESULTS: At the group level, there were no statistically significant changes in scores at follow up, although the participants scoring above designated cut-points were not necessarily the same individuals at the two time points. CONCLUSIONS: The study provided useful comparison data for use in evaluating the effects of cognitive rehabilitation interventions on mood and carer strain, showing that in the absence of intervention scores remain generally stable over time. Significant changes observed in intervention studies should be viewed in this context.     

Impaired digit span can predict further cognitive decline in older people with subjective memory complaint: a preliminary result

Subjective memory complaint (SMC) is common among elderly people, and is thought to be part of mild cognitive impairment (MCI). We evaluated whether impaired digit span (IDS) in older people with SMC can predict wider impairment in future neuropsychological tests that correspond to MCI. After a mean of 6.6 years from the initial assessment, we reevaluated 16 subjects with SMC and normal digit span (NDS) scores (mean age 57.6 ± 8.1 years) and 28 subjects with SMC and IDS scores (mean age 59.7 ± 9.9 years). The IDS group showed wider cognitive decline in tests of short-term verbal memory and category verbal fluency compared to the NDS group. IDS scores indicate an earlier step for conversion of SMC to MCI.     

Subjective cognitive complaints, neuropsychological performance, affective and behavioural symptoms in non-demented patients

OBJECTIVE: Subjective cognitive complaints (SCC) have been previously investigated to establish whether they are risk factors for dementia, but no clear-cut conclusions have emerged. In this study non-demented patients with SCC were studied and the neuropsychological findings, affective and behavioural aspects and parameters with the highest correct classifications in discriminating patients who had only SCC but no objective clinical and neuropsychological impairment, i.e. no cognitive impairment (NCI) patients and those with objective neuropsychological deficits, namely patients with mild cognitive (MCI) were analyzed. METHODS: Consecutive non-demented outpatients with SCC were enrolled of over 9 months and examined using neuropsychological tests and scales for depression, anxiety and behaviour. Clinical criteria and neuropsychological test results were used to classify patients into groups of NCI, MCI and subtypes of MCI. RESULTS: Ninety-two patients with SCC were included; 49 of them had objective deficits (MCI patients), whereas 43 were without any clinical and cognitive impairment (NCI patients). These patients had lower age, higher education and better general cognitive indices than MCI patients who had higher caregiver distress, depression and irritability. The combination of a battery for mental deterioration and for behavioural memory assessment were the most discriminative in differentiating the two groups. CONCLUSIONS: An objective cognitive impairment, reaching the criteria for a MCI diagnosis, was present in almost half of patients having SCC. MCI patients have more behavioural disturbances than NCI subjects. SCC should not be underestimated and appropriate neuropsychological assessment is required to reassure subjects with normal results and to identify patients with MCI.     

Anxiety disorder and accompanying subjective memory loss in the elderly as a predictor of future cognitive decline

OBJECTIVE: The aim of the study was to empirically investigate the hypothesis that anxiety in the elderly, secondary to loss of memory, predicts future cognitive decline. METHOD: The participants were 137 elderly subjects with no depression or cognitive impairment from a community geriatric assessment unit, 45% with anxiety. In addition to demographic characteristics, cognitive status was assessed using the Mini Mental State Examination; depression was assessed by Tucker's short Interviewer-Assisted Depression Rating Scale; anxiety by Sinoff's Short Anxiety Screening Test and Activities of Daily Living function by Shah's modified Barthel's Index. RESULTS: At follow-up 37 persons had dropped out, leaving 100 participants for final analysis. Mean re-examination time was 3.2 years with no group differences. The mean MMSE and modified Barthel scores decreased significantly more in those with anxiety. A relative risk of 3.96 for developing future cognitive impairment was found. Regression analysis showed that only anxiety was a significant predictor of cognitive decline. By path analysis, a more parsimonious model showed anxiety to have both a direct and an indirect effect on predicting future cognitive decline, and that the effect of loss of memory on cognitive decline was via anxiety. CONCLUSIONS: Anxiety is inter-related and inseparable with loss of memory and its presence is a strong predictor for future cognitive decline, directly or indirectly via depression. It appears that loss of memory is the initial problem with consequent development of anxiety. Therefore, anxiety, like depression, is probably an early predictor of future cognitive decline and even possible future cognitive impairment.     

Six-month course of mild cognitive impairment and affective symptoms in late-life depression

Mild cognitive impairment (MCI) is frequent in patients with late-life depression. Previous studies indicate that cognitive performance in these patients is not or only marginally improved when they recover from depression. However, recovery from cognitive impairments due to depression may have a longer time course than recovery from affective symptoms. In a group of 34 elderly depressed patients (mean age: 73.4 years) admitted to a gerontopsychiatric day-clinic, severity of depression and cognitive performance were assessed before the initiation of treatment and were reassessed 6 months later. At admission, 18 of 34 patients (53%) fulfilled the criteria for MCI, with a preponderance of impairments in short-term memory and visuospatial capabilities. At the 6-month follow-up, cognitive performance had not significantly improved for the entire group; 12 of 27 patients (44%) still were fulfilling the criteria for MCI. No relationships could be ascertained between cognitive impairment or functional level and severity or course of depression. Patients with diurnal variations of the depressive symptomatology were less likely to fully recover from depression.     

Subjective memory complaints,mood and MCI: a follow-up study

Objectives: Subjective memory complaints (SMC) are common in older people and previous research has shown an association with mood problems, such as depression and anxiety. SMC form part of the criteria for many definitions of mild cognitive impairment (MCI), but there is controversy over whether they should be included as they may be related more strongly to mood than to objective cognitive impairment. This study aims to clarify the relationship between mood and SMC in people with MCI.

Method: This paper reports an analysis of data from the Medical Research Council Cognitive Function and Ageing study. Structured interviews were conducted with community-dwelling older people to assess a range of aspects of cognitive functioning and mood. Data from two time points approximately 24 months apart were used in this analysis. At baseline, participants without dementia or severe cognitive impairment were categorised into three groups according to cognitive status. Mood was investigated by assessing symptoms of anxiety and depression which were defined using a diagnostic algorithm. Associations were tested using logistic regression and chi square analyses.

Results: A clear association was shown between SMC and mood, both cross-sectionally and over time. The relationship between our two competing definitions of MCI suggested that mood problems were more strongly related to the presence of SMC than objective cognitive impairment.

Conclusion: SMC may be a function of anxiety and depression rather than being related to objective cognitive function. This questions whether SMC should be included in definitions of MCI.     

Prospective memory on a novel clinical task in older adults with mild cognitive impairment and subjective cognitive decline

Despite the relevance of prospective memory to everyday functioning and the ability to live independently, prospective memory tasks are rarely incorporated into clinical evaluations of older adults. We investigated the validity and clinical utility of a recently developed measure, the Royal Prince Alfred Prospective Memory Test (RPA-ProMem), in a demographically diverse, non-demented, community-dwelling sample of 257 older adults (mean age = 80.78?years, 67.7% female) with amnestic mild cognitive impairment (aMCI, n = 18), nonamestic mild cognitive impairment (naMCI, n = 38), subjective cognitive decline (SCD, n = 83) despite intact performance on traditional episodic memory tests, and healthy controls (HC, n = 118). Those with aMCI and naMCI performed significantly worse than controls on the RPA-ProMem and its subtasks (time-based, event-based, short-term, long-term). Also, those with SCD scored significantly lower than controls on long-term, more naturalistic subtasks. Additional results supported the validity and inter-rater reliability of the RPA-ProMem and demonstrated a relation between test scores and informant reports of real-world functioning. The RPA-ProMem may help detect subtle cognitive changes manifested by individuals in the earliest stages of dementia, which may be difficult to capture with traditional episodic memory tests. Also, assessment of prospective memory can help guide the development of cognitive interventions for older adults at risk for dementia.     

Concepts of mild memory impairment in the elderly and their relationship to dementia—a review

The concept enshrined by Kral (1962) in the term ‘benign senescent forgetfulness’ is reviewed together with a number of other diagnostic terms synonymous with mild memory impairment. Data from epidemiological studies which employ them are presented and the relationship between ‘normal’ ageing, subjective memory complaints and dementia is discussed. Mild memory impairment in late life is associated with an increased risk of developing dementia but it is difficult from present studies to quantify this.     

Memory self-appraisal and depressive symptoms in people at genetic risk for Alzheimer's disease.

OBJECTIVES: A previous study found that subjective memory loss in middle-aged and older persons is associated with the major genetic risk for Alzheimer's disease, the apolipoprotein E-4 (APOE-4) allele. No previous study has focused on subjective memory complaints and depressive symptoms in the same subject population at genetic risk for Alzheimer's disease. METHOD: Sixty-six persons (mean age = 64 years, range = 43 to 82 years) without major depression or dementia but with mild age-related memory complaints were rated for severity of depressive symptoms, using the Hamilton Depression Rating Scale, and assessed for the presence of the APOE-4 allele. Severity of subjective memory loss was assessed using the Memory Functioning Questionnaire, which measures four memory domains: frequency of forgetting, seriousness of forgetting, retrospective functioning, and mnemonics usage. RESULTS: Depressive symptoms were significantly associated with subjective memory loss in subjects without the APOE-4 allele, for retrospective functioning (perceived change in memory) and mnemonics usage, but not in APOE-4 carriers. The same significant associations were found when the analysis was limited to the 44 subjects in the mid-age range (55-74 years), wherein APOE-4 confers its greatest effects on risk for Alzheimer's disease. CONCLUSION: These results confirm that mild depressive symptoms are related to subjective memory loss, but for some forms of memory complaint, the relationship holds true only for people without the major known genetic risk for Alzheimer's disease.     

Subjective cognitive decline in cognitively normal elders from the community or from a memory clinic: Differential affective and imaging correlates

Introduction

Subjective cognitive decline (SCD) could indicate preclinical Alzheimer's disease, but the existing literature is confounded by heterogeneous approaches to studying SCD. We assessed the differential cognitive, affective, and neuroimaging correlates of two aspects of SCD: reporting high cognitive difficulties on a self-rated questionnaire versus consulting at a memory clinic.

Neuroimaging and the differential diagnosis of early dementia: Quantitative CT scan analysis in patients attending a memory clinic

Seventy-eight consecutive patients who attended a ‘memory clinic’ underwent a standardized clinical examination including extensive laboratory tests and cranial computed tomography (CT). This brief report evaluates the contribution of quantitative CT scan analysis to the differential diagnosis of early dementia syndromes. Vascular changes were readily identified in 13 patients with a clinical history and findings compatible with vascular dementia. Enlargement of the anterior and Sylvian fissures and of the third and lateral ventricles was significantly more severe in a group of 29 patients diagnosed as Alzheimer's disease than in 36 ‘memory complainers’ with milder cognitive impairment or in 10 age-matched non-demented controls. Quantitative CT scan analysis alone permitted a correct diagnositc distinction between ‘memory complainers’ and patients with Alzheimer's disease in 83% of the cases, but led to an only modest improvement of the correct discrimination achieved by cognitive testing. Our results indicate that CT scans may aid the differentiation of ealry dementing conditions.