Biomedical subjects

Lars Bäckman

Publications and source records attributed to Lars Bäckman.

At least 37 records · Page 2Linked to original sources

PubMed2005

Long-term follow-up of patients with alcoholic liver disease after liver transplantation in Sweden: impact of structured management on recidivism.

OBJECTIVE: No systematic evaluation has been performed previously in the Scandinavian countries on patients transplanted for alcoholic liver disease (ALD). Data are limited on the impact of structured management of the alcohol problem on the risk of recidivism following transplantation in ALD. MATERIAL AND METHODS: A total of 103 ALD patients were compared with a control group of patients with non-alcoholic liver disease (NALD). The recidivism rates for ALD patients transplanted between 1988 and 1997 as well as after 1998 (institution of structured management) were compared. RESULTS: The median follow-up was 31 (6-60) months in the ALD group and 37 (12-63) months in the control group (NS). The overall survival rates at 1- and 5 years were, respectively, 81% and 69% for the ALD group and 87% and 83% for the non-alcoholic group. The proportion of patients with Child-Pugh C (75%) was higher in ALD patients than in NALD patients (44%) (p<0.01). Thirty-two (33%) ALD patients resumed taking some alcohol after transplantation; 17 patients (18%) were heavy drinkers. A multivariate analysis showed that: sex, age, marital and employment status, benzodiazepine use and a history of illicit drug abuse did not predict the risk of alcohol relapse post-Tx. Nineteen out of 40 (48%) patients transplanted before the start of structured management had resumed alcohol but 13 (22%) out of 58 after this intervention (p=0.002). CONCLUSIONS: ALD is a good indication for liver transplantation, with similar results in the ALD patients. Structured management of the alcohol problem before and after transplantation is important in minimizing the risk of recidivism.

Adult↗

PubMed2005

Design your own memory strategies! Self-generated strategy training versus mnemonic training in old age: an 8-month follow-up.

We examined maintenance effects following training in a self-generated strategy versus a mnemonic strategy, designed to improve recall of four-digit numbers in older adults. This was accomplished by reassessing participants from a previous study eight months after completion of training. A control group that received no training was also included. The results showed that both training groups maintained training-related gains in number recall performance eight months later in a criterion task providing cognitive support. However, when no support was provided, number recall performance for the mnemonic group dropped slightly whereas performance for the self-generated strategy group improved. The control group maintained performance across assessments. These data indicate the numerical memory training may result in long-term effects in older adults and that, under some conditions, practising one's own memory strategies may have advantages over mnemonic training in old age.

Aged↗

PubMed2005

Trimethoprim-sulphamethoxazole does not affect the pharmacokinetics of sirolimus in renal transplant recipients.

AIMS: The influence of the trimethoprim-sulphamethoxazole combination on the steady-state pharmacokinetics of sirolimus, a potent macrocyclic immunosuppressant, was studied in renal transplant recipients. METHODS: Fifteen kidney transplant recipients were treated with sirolimus 8-23 mg m(-2) in combination with azathioprine and prednisolone from the day of transplantation. Whole blood sirolimus AUC and C(max) were determined on days 6 and 7 after transplantation. On day 7, sirolimus was coadministered with the first dose of trimethoprim (80 mg) and sulphamethoxazole (400 mg). RESULTS: On day 6, the mean (95% confidence interval) whole blood sirolimus AUC((0-24 h)) was 1040 (846, 1234) ng ml(-1) and mean C(max) was 109 (88, 129) ng ml(-1). Corresponding values on day 7 were AUC((0-24 h)) 1060 (826, 1293) ng ml(-1) and C(max) mean 107 (87, 127) ng ml(-1). The mean difference in the dose-corrected AUC((0-24 h)) was 0.40% (-9.4, +10). CONCLUSIONS: A single dose of trimethoprim-sulphamethoxazole does not affect the pharmacokinetics of sirolimus in renal transplant patients.

Adult↗

PubMed2005

Longitudinal models of growth and survival applied to the early detection of Alzheimer's disease.

This article explores new statistical methodologies for using longitudinal data in the early prediction of Alzheimer's disease (AD). Specifically, the authors examine some new techniques that allow the joint or "shared" estimation of longitudinal components based on both duration (survival) and quantitative changes (growth curves). These new shared growth-survival parameter models may be used to characterize the declining functions that anticipate the onset of AD. The authors apply these models to data from the Kungsholmen Project, a longitudinal study of aging in Stockholm, Sweden. They examine age-based survival-frailty models for the onset of AD, latent growth-decline curve models for changes in cognition over age, and 3 alternative forms of models for the shared relationships of survival and early cognitive decline. The accuracy and reliability of this approach is considered for a better understanding of the developmental course of AD in these data, including the potential removal of biases due to subject selection.

Adult↗

PubMed2004

Recollective experience in odor recognition: influences of adult age and familiarity.

We examined recollective experience in odor memory as a function of age, intention to learn, and familiarity. Young and older adults studied a set of familiar and unfamiliar odors with incidental or intentional encoding instructions. At recognition, participants indicated whether their response was based on explicit recollection (remembering), a feeling of familiarity (knowing), or guessing. The results indicated no age-related differences in the distribution of experiential responses for unfamiliar odors. By contrast, for familiar odors the young demonstrated more explicit recollection than the older adults, who produced more "know" and "guess" responses. Intention to learn was unrelated to recollective experience. In addition, the observed age differences in "remember" responses for familiar odors were eliminated when odor naming was statistically controlled. This suggests that age-related deficits in activating specific odor knowledge (i.e., odor names) play an important role for age differences in recollective experience of olfactory information.

Adolescent↗

PubMed2004

A preclinical phase in vascular dementia: cognitive impairment three years before diagnosis.

Alzheimer's disease (AD) and vascular dementia (VaD) patients exhibit similar patterns of deficits in many cognitive tasks in the early clinical stages. Considering that preclinical cognitive deficits are well documented in AD, the purpose of the present study was to investigate if such deficits are also present in VaD. The cognitive outcome measure was the Mini-Mental State Examination (MMSE). The sample was taken from a population-based study and consisted of 699 persons who were nondemented at baseline, but out of whom 35 persons were diagnosed with VaD and 170 with AD at a 3-year follow-up. Both the incident VaD and AD cases exhibited baseline deficits on the total score of the MMSE and three of the subscales: orientation to time, orientation to place, and delayed memory. Further, both dementia groups exhibited precipitous decline on most MMSE subscales during the 3-year follow-up period. Logistic regression analyses showed that all subscales that revealed deficits at baseline predicted dementia status at follow-up. Delayed memory was the best predictor in both preclinical VaD and preclinical AD. Thus, these results demonstrate preclinical cognitive deficits in VaD in a measure of global cognitive functioning, which closely resemble those observed in AD. This observation suggests that circulatory disturbance is associated with cognitive problems several years before the actual VaD diagnosis.

Aged↗

PubMed2004

Cognitive functioning in preclinical vascular dementia: a 6-year follow-up.

BACKGROUND AND PURPOSE: Recent studies have shown that cognitive deficits are present during the years preceding a diagnosis of vascular dementia (VaD). The aims of this study were to (1) extend previous research by examining whether cognitive deficits are already present 6 years before diagnosis, and (2) examine the strength of the association between cognitive performance and a future VaD diagnosis after controlling for previous vascular disorders. METHODS: Subjects from a population-based study of very old persons (> or =75) were examined with a test of global cognitive functioning (the Mini-Mental State Examination [MMSE]) at 3 occasions over a 6-year period. The study sample was nondemented the first 2 measurement times. On the last occasion, 22 individuals were diagnosed with VaD, and 450 persons remained nondemented. RESULTS: The preclinical VaD group showed no MMSE deficits 6 years before diagnosis (P>0.10) compared with the controls. However, 3 years before diagnosis, poor cognitive performance was significantly associated with forthcoming VaD after controlling for demographic factors and prior vascular disorders (odds ratio, 2.55; 95% CI, 1.67 to 3.89). CONCLUSIONS: This study extends previous findings on preclinical cognitive deficits in VaD and suggests that cognitive measures can be useful in the process of recognizing individuals at risk for developing VaD to initiate early treatment.

Aged↗

PubMed2004

Sex-differential brain activation during exposure to female and male faces.

Sex-discriminating facial features are examples of visual information involved in guiding social behavior. We used functional magnetic resonance imaging (fMRI) to assess brain responses in face-relevant brain areas in men and women during exposure to neutral male and female faces. An increased fMRI signal was found in the left amygdala and adjacent anterior temporal regions in men, but not in women, during exposure to faces of the opposite versus the same sex. These data indicate that the relationship between the sex of the subject and the sex of the face affects activity in the inferior temporal lobe. The sex-differential nature of this activation pattern may reflect sex differences in cognitive style and attentional processes when confronting faces of the opposite sex.

Adult↗

PubMed2004

Liver transplantation for primary sclerosing cholangitis; predictors and consequences of hepatobiliary malignancy.

BACKGROUND/AIMS: Hepatobiliary malignancies are frequently seen in primary sclerosing cholangitis (PSC) and they complicate the evaluation of patients and timing of liver transplantation. METHODS: Data from all Nordic PSC patients listed for liver transplantation during 1990-2001 were recorded prospectively. Predictors of hepatobiliary malignancy and patient survival rates have been analysed. RESULTS: Hepatobiliary malignancy was found in 52/255 (20%) patients accepted to the waiting list. Recent diagnosis of PSC, no ursodeoxycholic acid (UDCA) treatment, clinical suspicion and previous colorectal-cancer were predictors of malignancy. Among 89 patients with a strong suspicion of malignancy prior to acceptance, 35 (39%) had confirmed malignancy. A clinical suspicion had been raised in 35/52 (67%) patients with malignancy. Malignancy was found in 31/223 patients who received a liver allograft. The 1-, 3- and 5-year patient survival rates following transplantation for patients with PSC and cholangiocarcinoma were 65, 35 and 35%, respectively. CONCLUSIONS: Hepatobiliary malignancy is suspected in 1/3 of the PSC patients and found in 1/5. Although cholangiocarcinoma is regarded as a contraindication to liver transplantation (LTX), PSC patients with cholangiocarcinoma had a 35% 5-year survival following transplantation.

Adult↗

PubMed2004

Mobilisation of heavy metals by deicing salts in a roadside environment.

The seasonal variations of some selected heavy metals (Cd, Cu, Pb and Zn) and principal anions in soil solutions were monitored as a function of distance from the road at two field sites in Sweden. During the winter, the conductivity, concentrations of dissolved sodium and chloride increased dramatically due to the application of deicing agents (i.e. NaCl). Due to ion exchange, the pH decreased one unit in the soil solutions, whereas the concentrations of total organic carbon decreased due to coagulation and/or sorption to stationary solids. The heavy metal concentrations increased during the winter, but through different mechanisms. Cadmium concentrations in the aqueous phase increased as a response to ion exchange, possibly also enhanced by the formation of chloride complexes. Similarly, the concentrations of zinc increased, due to ion exchange, with calcium and protons. The mechanisms of mobilisation for copper and lead were not that clear probably due to association with coagulated or sorbed organic matter in combination with colloid dispersion.

Colloids↗

PubMed2004

Similar patterns of cognitive deficits in the preclinical phases of vascular dementia and Alzheimer's disease.

We investigated whether (1) cognitive deficits are present among persons who will be diagnosed with vascular dementia (VaD) 3 years later, and (2) the pattern of such deficits is similar to that observed in preclinical Alzheimer's disease (AD). The VaD diagnosis was a diagnosis of post-stroke dementia. Population-based samples of 15 incident VaD cases, 43 incident AD cases, and 149 normal controls were compared on tests of episodic and short-term memory, verbal fluency, and visuospatial skill. Both dementia groups showed preclinical impairment relative controls on tasks assessing episodic memory 3 years before diagnosis, and there were no differences between these groups on any cognitive measure. The existence of a preclinical phase in the present VaD cases suggests that circulatory disturbance may affect cognitive performance before the occurrence of stroke that leads to clinical VaD. These results extend previous findings of similar patterns of cognitive deficits in the early clinical phases of AD and VaD to the preclinical phases of these diseases.

Aged↗

PubMed2004

Apolipoprotein E and cognitive performance: a meta-analysis.

The epsilon4 allele of the apolipoprotein E (APOE) gene is a known risk factor for Alzheimer's disease and may also affect cognitive performance in normal aging. Evidence of the presence and magnitude of epsilon4-related cognitive deficits was examined with a meta-analysis of the available literature. Thirty-eight studies were included, and cognitive performance was collapsed into 8 domains. Results indicated significant APOE-epsilon4 group differences for global cognitive functioning, episodic memory, and executive functioning, in favor of non-epsilon4 carriers. In addition, older age and APOE-epsilon4 heterozygosity was associated with smaller epsilon4-related impairments. The meta-analysis results suggest that APOE-epsilon4 genotype does affect cognitive performance in healthy aging, although the influence is relatively small and specific to certain domains of cognitive performance.

Adult↗

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↗

PubMed2004

Selective sex differences in declarative memory.

Sex invariance of a six-factor, higher order model of declarative memory (two second-order factors: episodic and semantic memory; and four first-order factors: recall, recognition, fluency, and knowledge) was established for 1,796 participants (35-85 years). Metric invariance of first- and second-order factor loadings across sex was demonstrated. At the second-order level, a female advantage was observed for both episodic and semantic memory. At the first-order level, sex differences in episodic memory were apparent for both recall and recognition, whereas the differences in semantic memory were driven by a female superiority in fluency. Additional tests of sex differences in three age groups (35-50, 55-65, and 70-85 years of age) indicated that the female superiority in declarative memory diminished with advancing age. The factor-specific sex differences are discussed in relation to sex differences in hippocampal function.

Adult↗

PubMed2004

Enhanced occipital and anterior cingulate activation in men but not in women during exposure to angry and fearful male faces.

Blood-oxygenation-level-dependent signal was measured with functional magnetic resonance imaging in 24 healthy young subjects (12 men and 12 women) during viewing of angry, fearful, and neutral male and female face pictures. Exposure to angry male as opposed to angry female faces activated the visual cortex and the anterior cingulate gyrus significantly more in men than in women. A similar sex-differential brain activation pattern was present during exposure to fearful but not neutral faces. Previous behavioral studies indicate enhanced physiological arousal in men but not in women during exposure to angry male asopposed to female faces, and brain imaging studies have shown that the occipital cortex and the anterior cingulate gyrus are influenced by activity in the autonomic nervous system as well as by visualattention. Hence, we suggest that the elevated occipital and anterior cingulate activation in men during confrontation with other angry and fearful males may reflect enhanced vigilance in a potentially dangerous situation.

Adult↗

PubMed2003

[Liver dialysis using MARS in acute hepatic failure. Promising results in a pilot setting].

Acute hepatic failure (AHF) is a life threatening condition with a high mortality rate. There is a need to buy time, either waiting for the liver to regenerate or waiting for urgent liver transplantation. Different modalities of "liver dialysis" have been used during the last decades but of no true success. However, a new technique has been developed called the MARS (Molecular Adsorbent Recycling System) built upon the same principle as haemodialysis but with the capacity to also remove albumin bound compounds thought to be toxic to the liver. This is a report of our ten first cases, all having AHF and considered for liver transplantation. The survival rate was 7/10 and of the 5 patients in need of 5 or more treatments all but one survived. In these cases the MARS-treatment seemed to have positive effects on the course and outcome of the disease but there are a need for controlled trials to clearly prove the benefit of the treatment.

Adult↗

PubMed2003

Neural correlates of training-related memory improvement in adulthood and aging.

Cognitive studies show that both younger and older adults can increase their memory performance after training in using a visuospatial mnemonic, although age-related memory deficits tend to be magnified rather than reduced after training. Little is known about the changes in functional brain activity that accompany training-induced memory enhancement, and whether age-related activity changes are associated with the size of training-related gains. Here, we demonstrate that younger adults show increased activity during memory encoding in occipito-parietal and frontal brain regions after learning the mnemonic. Older adults did not show increased frontal activity, and only those elderly persons who benefited from the mnemonic showed increased occipito-parietal activity. These findings suggest that age-related differences in cognitive reserve capacity may reflect both a frontal processing deficiency and a posterior production deficiency.

Adult↗