Biomedical subjects

Ake Wahlin

Publications and source records attributed to Ake Wahlin.

17 recordsLinked to original sources

PubMed2006

Cognitive and social functioning in recovery from depression: results from a population-based three-year follow-up.

BACKGROUND: This study prospectively examined cognitive and social functioning in recovery from depression using participants sampled from the general population. METHOD: Seventy-six depressed persons fulfilling (n=41) and not fulfilling (n=35) the criteria for DSM-IV depression at a three-year follow-up were compared with respect to episodic memory performance and social functioning at baseline (T1), at follow-up (T2) and change across time. RESULTS: The groups did not differ in episodic memory performance either at T1, T2 or in residual change. However, the groups differed in social functioning at T2 and in residual change indicating improved social functioning in the recovered group. LIMITATION: The absence of a healthy control group at follow-up. CONCLUSION: Despite the symptomatic improvement and improved social functioning, cognitive functioning does not follow this general recovery trend, at least not in the three-year interval examined.

Adult↗

PubMed2006

Mini Nutritional Assessment of rural elderly people in Bangladesh: the impact of demographic, socio-economic and health factors.

OBJECTIVE: In stating the Millennium Development Goals, the United Nations aims to halve malnutrition around the world by 2015. Nutritional status of the elderly population in low-income countries is seldom focused upon. The present study aimed to evaluate the magnitude of malnutrition among an elderly population in rural Bangladesh. DESIGN AND SETTING: Data collection for a multidimensional cross-sectional study of community-based elderly people aged 60 years and over was conducted in a rural area in Bangladesh. SUBJECTS: Of 850 randomly selected elderly individuals, 625 participated in home interviews. Complete nutritional information was available for 457 individuals (mean age 69+/-8 years, 55% female). Nutritional status was assessed using an adapted form of the Mini Nutritional Assessment (MNA) including body mass index (BMI). Age, sex, education, household expenditure on food and self-reported health problems were investigated as potential predictors of nutritional status. RESULTS: BMI<18.5 kg m(-2), indicating chronic energy deficiency, was found in 50% of the population. MNA revealed a prevalence of 26% for protein-energy malnutrition and 62% for risk of malnutrition. Health problems rather than age had a negative impact on nutritional status. Level of education and food expenditure were directly associated with nutritional status. CONCLUSION: In order to reduce world hunger by half in the coming decade, it is important to recognise that a substantial proportion of the elderly population, particularly in low-income countries, is undernourished.

Aged↗

PubMed2006

How do health and biological age influence chronological age and sex differences in cognitive aging: moderating, mediating, or both?

Much research on cognitive competence in normal older adults has documented age and sex differences. The authors used new cross-sectional data from the Victoria Longitudinal Study (VLS) (n=386; age 61 to 95 years) to examine how health and biological age influence age and sex differences in cognitive aging. The authors found evidence for both moderating and mediating influences. Age differences were moderated by health status, such that the negative effects of age were most pronounced among participants of relatively better health. Sex differences were moderated by health and were more pronounced among participants reporting comparatively poorer health. Although health mediated a notable amount of age-related cognitive variation, BioAge mediated considerably more variance, even after statistical control for differences in health. A complex pattern emerged for the mediation of sex differences: Although BioAge accounted for sex-related variation in cognitive performance, health operated to suppress these differences. Overall, both health and BioAge predicted cognitive variation independently of chronological age.

Aged↗

PubMed2005

Longitudinal evidence of the impact of normal thyroid stimulating hormone variations on cognitive functioning in very old age.

The purpose of this study was to examine longitudinal associations among thyroid stimulating hormone (TSH) levels and cognitive performance. Data collected at the first three assessment times, approximately 3 years apart, are reported for the survivors (n=45) from a previously published cross-sectional study. Participants were aged 75-93 years at baseline, and data reported were collected in the Kungsholmen Project, a longitudinal project investigating aging and dementia. Analyses revealed that although declining verbal fluency and visuospatial abilities were accompanied by simultaneously declining TSH levels, the pattern of cross-sectional and longitudinal results are interpreted such that declining TSH levels may have caused episodic memory deficits later on. These results were obtained in the examination of 6-year but not 3-year change, and after removal of the cognitive variation associated with depressive mood symptoms.

Affect↗

PubMed2005

Cognitive functioning in post-polio patients with and without general fatigue.

OBJECTIVE AND DESIGN: This study examined 2 main hypotheses. First, whether patients with post-polio suffering from general fatigue (n=10) demonstrate cognitive deficits compared with patients with post-polio without general fatigue (n=10). Secondly, by systematically varied test order administration we examined whether such differences varied as a function of increasing cognitive load during cognitive testing. SUBJECTS: Twenty patients diagnosed with post-polio syndrome, 10 with general fatigue and 10 without fatigue. RESULTS: Neither of the 2 hypotheses were confirmed. The group with general fatigue reported elevated levels of depression. However, no systematic association between level of depression and cognitive performance could be detected. CONCLUSION: The results of this study provide no evidence that general fatigue or cognitive load affects cognitive functioning in post-polio.

Adult↗

PubMed2005

Apolipoprotein E, B vitamins, and cognitive function in older adults.

Recognition of dated and contemporary famous faces, short-term memory, and visuospatial abilities were investigated in adults aged 75 years and older as a function of apolipoprotein E (APOE) genotype, epsilon4 or not epsilon4, and whether participants recorded normal or low levels of B vitamins. No associations between B vitamins and APOE were identified in respect to short-term memory or visuospatial skills, or for contemporary famous faces. However, in respect to the recognition of dated famous faces, deficits in persons carrying the epsilon4 allele who also recorded low vitamin B(12) values were found. The results suggest that the neurological structures and processes supporting face recognition may be vulnerable to the combined influence of the APOE epsilon4 allele and low levels of vitamin B(12). This finding was unrelated to incipient dementia up to 6 years following testing. The results are discussed with reference to the neuroanatomical reserves that epsilon4 carriers may possess.

Aged↗

PubMed2005

The sensory-cognition association in adulthood: Different magnitudes for processing speed, inhibition, episodic memory, and false memory?

One hundred and forty-six participants (age range = 20-80) completed a battery of tests designed to measure visual acuity, processing speed, inhibition, episodic memory and false memory. The relations between visual acuity and general cognitive ability, as well as between visual acuity and the indicators of this construct, were evaluated with structural equation modeling. The measurement model confirmed that the indicators of the individual cognitive abilities could be grouped into a general cognitive functioning factor. However, the relation between episodic and false memory was not completely explained by the shared association with this general factor. Furthermore, visual acuity predicted approximately half of the age-related variance in the general cognition factor. Also, the proportion of age-related variance shared with vision was highest in inhibition and lowest in false memory. The results are discussed in the light of common cause accounts of cognitive aging.

Adult↗

PubMed2004

Utilization of cognitive support in episodic free recall as a function of apolipoprotein E and vitamin B12 or folate among adults aged 75 years and older.

Apolipoprotein E (APOE), vitamin B12, and folate were examined in relation to free recall among 167 community-based older adults. Cognitive support at encoding and retrieval was also taken into account. Participants were classified as APOE e4 or non-epsilon4 allele carriers and as either low or normal vitamin B12 or folate status. A significant association was identified between low vitamin B12 and the epsilon4 genotype in respect to free recall, but only in circumstances of low cognitive support. This result remained after removing dementia cases that occurred up to 6 years after testing. A similar, but nonsignificant, trend was evident in relation to folate. The research is discussed with reference to vulnerability models and genetic influences on brain reserves.

Aged↗

PubMed2004

The extent of stability and change in episodic and semantic memory in old age: demographic predictors of level and change.

Structural stability and change in semantic and episodic memory performance as well as interindividual differences in 5-year changes in these constructs are examined within a sample of older adults (age rangeT1 = 60-80; n = 361). Interindividual differences in change were limited but significant. Stability coefficients were higher for semantic memory (.95) than for episodic memory (.87). Changes in episodic and semantic memory performance were strongly associated (r =.68). Across time, variances and covariances increased, and a tendency toward dedifferentiation in terms of increasing correlations was found. Chronological age was related to both level and change, but gender and education were only related to level of memory performance. Collectively, these results depict relatively high degrees of structural stability and stability of interindividual differences in declarative memory in old age.

Age Factors↗

PubMed2004

Episodic memory change in late adulthood: generalizability across samples and performance indices.

Younger adults recall more information from episodic memory tasks than do older adults. Because longitudinal studies are rare and often incompatible, the extent of actual late-life memory change is not well established. We assemble two different longitudinal samples of normal older adults, each of which is tested twice at a 3-year interval, using a large battery of episodic memory indicators. Together, two-wave data from both the Victoria Longitudinal Study in Canada (n = 400) and the Kungsholmen Project in Sweden (n = 168) cover a 40-year span of adulthood, ranging from 54 to 94 years of age. Principal memory tasks include categorizable word lists, story recall, and random word lists, as well as indicators of cognitive support. Overall, an examination of performance on sets of common and complementary episodic tasks reveals that, for both samples, actual 3-year changes are modest and that, when decline occurs, it is gradual. The exception-greater decline for more supported tasks-suggests that these may be especially sensitive to late-life changes.

Adult↗

PubMed2003

Selective adult age differences in an age-invariant multifactor model of declarative memory.

Confirmatory factor analysis was used to test competing models of declarative memory. Data from middle-aged participants provided support for a model comprised of 2 2nd-order (episodic and semantic memory) and 4 1st-order (recall, recognition, fluency, and knowledge) factors. Extending this model across young-old and old-old participants established support for age invariance. Tests of group differences showed an age deficit in episodic memory that was more pronounced for recall than for recognition. For semantic memory, there was an increase in knowledge from middle to young-old age and thereafter a decrease. Overall, the results support the view that episodic memory is more age sensitive than semantic memory, but they also indicate that aging has differential effects within these 2 forms of memory.

Adult↗

PubMed2003

Interrelations between subjective health and episodic memory change in Swedish and Canadian samples of older adults.

Recent research has documented associations between subjective health ratings and objective indicators of disease and death. Less is known about relations between subjective health ratings and level of cognitive performance in older adults. In this study, we explored whether subjective health ratings are related to episodic memory performance, both concurrently and across a three-year longitudinal interval. Persons aged 75-84 years, and participating in the Swedish Kungsholmen Project (n = 105) or the Canadian Victoria Longitudinal Study (n = 71), were examined. Results showed that in both samples, while the cross-sectional relationship was non-significant, longitudinal change in perceptions of subjective health were related to change in episodic memory performance. Next, the two samples were combined in additional analyses. Here, results further revealed that the associations between longitudinal change in subjective health and memory performance generalized across samples independently of demographic, changing physical health status, and subjective memory decline differences. Thus, the present findings suggest that subjective health may be added to the growing number of individual-difference variables that are predictive of episodic memory change in very old age.

Aged↗

PubMed2002

Influences of preclinical dementia and impending death on the magnitude of age-related cognitive deficits.

The authors examined the influence of preclinical dementia and impending death on the cross-sectional relationship between age and performance in tasks assessing episodic memory, visuospatial skill, and verbal fluency. Increasing age was associated with a general decrease in cognitive performance. In addition, those who were to be diagnosed with dementia or had died by a 3-year follow-up, were older, and performed at a lower level than the remaining sample across all cognitive tasks at baseline. Nevertheless, removal of the preclinical dementia and impending death groups from the original sample affected the cross-sectional age-cognition relations relatively little. This pattern of findings suggests that the biological aging process exerts negative influences on cognitive functioning beyond those resulting from disease and mortality.

Age Factors↗

PubMed2002

Cognitive functioning in Alzheimer's disease and vascular dementia: further evidence for similar patterns of deficits.

The purpose of the present study was to examine possible differences in patterns of cognitive performance between population-based samples of Alzheimer's disease (AD; n = 51) and vascular dementia (AD; n = 14) patients between 75 and 96 years of age. The two demented groups were comparable in age, years of education, gender distribution, and severity of dementia. The selection of cognitive tasks (letter and category fluency, Block design, Clock reading and setting, and episodic face recognition) was thought to address some of the inconsistencies in previous research. The main finding was that AD and AD patients were comparable on most tasks, although robust dementia-related deficiencies were found when comparing the results of the demented participants with those of the control participants. These findings suggest that AD and AD may affect several basic cognitive functions in an equal manner.

Aged↗

PubMed2002

Reference values for serum levels of vitamin B12 and folic acid in a population-based sample of adults between 35 and 80 years of age.

OBJECTIVES: To examine folic acid and vitamin B12 status in a group of 1000 persons sampled from the community of Umeå, Sweden, and aged 35, 40, 45, 50, 55, 60, 65, 70, 75 or 80 years. Reference data for folate and age-stratified reference data for vitamin B12 are presented, together with an examination of potential confounders. MEASUREMENTS: All subjects participated in extensive health examinations and interviews, and laboratory blood testing was performed. RESULTS: A series of exclusion criteria were applied, and data from 961 subjects were analysed. Vitamin B12 levels were found to decrease with increasing age, whereas folate levels remained constant across the age span studied. None of the vitamins was found to vary with sex, education, smoking or alcohol consumption, body mass index, prescription-free vitamin supplements, level of haemoglobin, or mean cell volume of erythrocytes. Further, none of these factors was associated with the age-related decrease of vitamin B12 level. CONCLUSIONS: The offered reference ranges should be used only in order to rule out deficiency. For B12 levels, the age of the subject should be considered such that, for elderly people in particular, values above the medians should be considered as indicative of normal vitamin status.

Adult↗

PubMed2002

Negligible effects of depression on verbal and spatial performance in Alzheimer's disease.

We examined whether a diagnosis of depression affects verbal and visuospatial performance in Alzheimer's disease (AD). Using data from a population-based study, persons with AD and depression (AD/D), AD alone and a control group of normal older adults were compared in two tests of verbal ability (category and letter fluency) and two tests of visuospatial skill (block design and clock drawing). As expected, there were clear AD-related deficits across all cognitive tasks. More importantly, the AD and AD/D groups were indistinguishable on all task variables. The lack of effects of depression was discussed relative to the view that those symptoms of this disease which are especially detrimental to cognitive functioning (e.g. concentration difficulties, lack of interest, loss of energy) may already be present in AD as a result of the neurodegenerative process.

Aged↗

PubMedDate not supplied

Cognitive functioning in a population-based sample of very old non-demented and non-depressed persons: the impact of diabetes.

The main objectives of this study were to examine potential effects on cognitive functioning of diabetes and some major cardiovascular signs and diseases in very old age. Analyses were based on data from the Kungsholmen project and involved a population-based sample of non-demented and non-depressed persons aged 75-96 years. Diabetics (n=36) were compared with non-diabetic persons (n=356), and all participants were assessed with an extensive medical examination, specific diagnostic interviews, and laboratory blood analyses. Cognitive ability was indexed by means of the Mini-Mental State Examination (MMSE). The results showed that diabetics perform significantly worse on the MMSE than do non-diabetics, and that the MMSE-performance of elderly with cardiovascular disease (CVD) is significantly worse than in those without CVD. Controlling for cardiovascular signs and diseases did not alter the effects of diabetes. Examination of interaction terms, finally, indicated that, in the examined age range, the effects of diabetes do not vary across age, educational levels or variations in cardiovascular health. The results suggest that cognitive deficits associated with diabetes in very old age may be detected with the MMSE.

Journal Article↗