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L Niinistö

Publications and source records attributed to L Niinistö.

At least 19 recordsLinked to original sources
PubMed2001

Prevalence of Alzheimer's disease in very elderly people: a prospective neuropathological study.

BACKGROUND: No previous autopsy-controlled, prospective, and population-based studies are available on the prevalence of AD in very elderly people. OBJECTIVE: To study the point prevalence of neuropathologically defined AD in a population of people at least 85 years of age, stratified according to their APOE genotype. METHODS: A population-based sample of 532 (of a total population of 601) elderly Finnish individuals, aged 85 years or more, were clinically tested for dementia in 1991 (with follow-up studies of the survivors in 1994, 1996, and 1999) and genotyped for APOE. An autopsy involving neuropathologic diagnosis of AD according to modified consensus criteria was performed in 118 of 198 deceased subjects who had been demented on April 1, 1991, and in 62 of 201 nondemented individuals. RESULTS: The prevalence of neuropathologically defined AD was 33%, whereas the prevalence of clinically diagnosed AD was 16%. There was a highly significant (p < 0.001) association between the APOE epsilon4 allele and AD: Sixty-three percent of APOE epsilon4 carriers and 20% of noncarriers had neuropathologic AD. The respective figures in subjects aged 90 years or more were 71 and 22%. CONCLUSIONS: The prevalence of neuropathologically defined AD is higher than that reported in most previous studies based on clinical diagnosis. The discrepancy between the neuropathologic and clinical diagnoses of AD in very elderly subjects may affect the results of population-based studies. The APOE genotype has a strong effect on the prevalence of neuropathologically defined AD, even after 90 years of age.

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PubMed2001

Delirium in the non-demented oldest old in the general population: risk factors and prognosis.

BACKGROUND: The oldest old are prone to develop delirium. Studies into risk factors for delirium have been carried out predominantly in younger age groups. The aim of this population-based follow-up study was to investigate the risk factors for delirium requiring medical attention and subsequent prognosis in the non-demented general population aged > or = 85 years. METHOD: The study included the non-demented subjects in the population-based Vantaa 85+ study. After the 3-year observation period, 199 subjects (91% of those surviving) were re-examined and their medical records were evaluated for episodes of delirium. The subjects were followed up with respect to mortality for another 2 years. RESULTS: During the 3-year observational period, 20 subjects (10%) had been diagnosed as having had an episode of delirium. A Mini-Mental State Examination score of < 24 (odds ratio (OR) 3.44, confidence interval (CI = 95%) 1.27-9.32) and high systolic blood pressure (OR 3.08, CI 1.08-8.79) were identified as independent risk factors for delirium. The association between the delirium episode and a new diagnosis of dementia was significant ( p = 0.001). The mortality rate was greater among those subjects who experienced delirium than among subjects without this syndrome ( p = 0.008). CONCLUSIONS: Mild cognitive impairment and high systolic blood pressure were found to be risk factors for delirium requiring medical attention in the general non-demented population aged > or = 85 years. The study also highlights the significant association between delirium and a new dementia diagnosis in this age group.

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PubMed2001

Does apolipoprotein E influence learning and memory in the nondemented oldest old?

The objective of this study was to analyze the relationship of the apolipoprotein E (apoE) epsilon4 and epsilon2 alleles to learning and memory performances in the nondemented oldest old. Forty-six nondemented persons aged 85 years or over from a randomly selected group of 128 subjects in Vantaa, Finland, were studied. ApoE genotyping was performed using the minisequencing technique. A structured clinical examination and interview were carried out. The test variables studied were learning and memory scores (from the Fuld Object-Memory Evaluation), verbal fluency, and conceptualization (the Similarities subtest of the WAIS-R). We compared apoE-epsilon4 carriers to noncarriers and apoE-epsilon2 carriers to noncarriers. No statistically significant differences were found in any of the test variables. The results failed to confirm the hypotheses that poor cognitive performance is associated with the apoE-epsilon4 allele and good performance with the apoE-epsilon2 allele in the oldest old. This suggests that the apoE alleles do not have a detectable relationship to learning and memory in nondemented very elderly people.

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PubMed2001

Association of lipoprotein lipase Ser447Ter polymorphism with brain infarction: a population-based neuropathological study.

BACKGROUND: Variants of the lipoprotein lipase (LPL) gene have been shown to influence serum lipid levels, risk of coronary heart disease and, as found recently, risk of clinical ischaemic cerebrovascular disease. Here we tested for an association between brain infarction and two common polymorphisms of the LPL gene, Ser447Ter and Asn291 Ser. METHOD: To avoid ascertainment and selection bias involved in many association studies, we compared the distribution of these polymorphisms in neuropathologically verified patients (n = 119) vs controls (n = 133) derived from a prospective, population-based study (the Vantaa 85+ study). RESULTS: The LPL Ter447 variant was negatively associated with neuropathologically verified brain infarcts (P = 0.006), and even more strongly with small brain infarcts (P = 0.004). In addition, we found that the Ter447 variant was associated with higher serum HDL chblesterol (P = 0.004) and lower triglyceride levels (P= 0.003), and that it was negatively associated with pathologically verified severe coronary artery disease (P=0.001) in the Vantaa 85+ study sample. The Asn291Ser polymorphism was not significantly associated with brain infarction. CONCLUSION: The Ter447 variant of LPL is associated with decreased risk of brain infarction and coronary artery disease in our very elderly population.

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PubMed2000

Cardiovascular risk factors and Alzheimer's disease: a genetic association study in a population aged 85 or over.

Increasing evidence suggests a relation between vascular disorders and late-onset Alzheimer's disease (AD). We performed an association analysis of low-density lipoprotein receptor-related protein (LRP), lipoprotein lipase (LPL), and angiotensin converting enzyme (ACE) genes, known to be involved in vascular disorders, and AD. Genotyping was carried out in 113 patients with clinically defined Alzheimer's disease (NINCDS-ADRDA criteria) and 203 non-demented controls in a prospective, population-based study of people aged 85 years or over (Vantaa 85+ Study). Corresponding analysis was performed on 121 neuropathologically verified AD patients (CERAD criteria) and 75 controls derived from the same study population. We did not find significant associations between the polymorphisms studied and AD. However, analysis of the LPL polymorphism showed a weak trend (uncorrected P-value 0.095) towards protection against neuropathologically defined AD. Our study is based on very elderly Finns. Therefore, further studies are warranted in other populations.

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PubMed1999

The prevalence and associates of depressive disorders in the oldest-old Finns.

AIM: To describe the prevalence and associates of major depression and minor depression among the Finnish non-demented population aged 85 years and older (n = 339). METHODS: DSM-III-R criteria were used in diagnosing major depression and dementia. Minor depression was diagnosed by the physician in those who did not fulfil the DSM-III-R criteria for major depression, but had still at least two depressive symptoms. In the first phase, cross-tabulation was used to determine relative risks (RR) and their 95% confidential intervals (95% CI). An additive logistic regression model was then used to find the independent associates of depressive disorders. RESULTS: The prevalence of major depression was 8.1% in men and 4.9% in women, and that of minor depression 18.9% in men and 18.5% in women. In men major depression was associated independently with poor physical health and in women with rare contact with family or friends and poor physical health. Minor depression was associated independently with poor physical health and previous myocardial infarction in men and with poor physical health, a poor ability to walk, and smoking in women. CONCLUSIONS: The prevalence of depressive disorders is quite high among the oldest-old Finns. The factors associated with major and minor depression are largely similar. Although the results suggest that psychosocial stress factors affect the development of both major and minor depression in the oldest-old, no conclusions about causality can be made.

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PubMed1999

Genetic association of alpha2-macroglobulin with Alzheimer's disease in a Finnish elderly population.

Recently, two studies have reported an association between the alpha2-macroglobulin gene on chromosome 12 and late-onset Alzheimer's disease, whereas others have not been able to replicate these findings. By using a prospective population-based study, we have investigated the relation between two polymorphisms in this gene with the presence of the disease and also with the extent of pathological changes in the cerebral cortex. The Vantaa 85+ Study includes all 601 persons, at least 85 years of age, who were living in Vantaa, Finland, on April 1, 1991. The neocortical beta-amyloid protein load and the number of neurofibrillary tangles were determined on tissue sections by using methenamine silver staining and a modified Bielschowsky staining, respectively. The A/A genotype in exon 24 of the alpha2-macroglobulin gene was associated with neuropathologically defined diagnosis of Alzheimer's disease according to the CERAD (Consortium to Establish a Registry for Alzheimer's Disease) criteria and with an increase in the neocortical beta-amyloid protein load. The effect of this association was stronger in the apolipoprotein E epsilon4-negative group. Therefore, genetic variability in the alpha2-macroglobulin gene is a risk factor associated with neuropathologically defined Alzheimer's disease in our population, as well as with the extent of neocortical beta-amyloid protein deposition.

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PubMed1997

Depression measured by the Zung Depression Status Inventory is very rare in a Finnish population aged 85 years and over.

The purpose of this study was to obtain information about the prevalence of depressive symptoms in a representative sample of elderly subjects aged 85 years and over. The study was carried out as a population-based interview study in the City of Vantaa in Finland. The Zung Depression Status Inventory (DSI) was used to evaluate various depressive symptoms in this study population. The DSI scores range from 20 to 80; the higher the score, the more severe the disturbance. In subjects interviewed (n = 467, 362 women, 105 men), the prevalence estimates of depression with cutoff scores used in earlier studies (40 and 48) were very low: 5.2% and 1.1%. Also, the mean DSI score (SD) was very low, 27.9 (6.4). The scores tended to decrease with age, although the differences were not statistically significant. The DSI means were 28.0 (6.1) for women and 27.3 (7.2) for men (p = .0349). Women had a greater risk of being classified as depressed on the DSI (odds ratio: 1.60, 95% confidence interval: 1.00-2.57, p = .049). Feelings of emptiness, personal devaluation, and depressive mood were the most common depressive symptoms. In conclusion, the present population-based study shows that subjective experience of depression is very rare in Finnish people aged 85+. Our results suggest that optimistic mood might give some protection against death.

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PubMed1996

Quantification of antimony depth profiles in Sb-doped tin dioxide thin films.

Sb-doped SnO(2) thin films, deposited by atomic layer epitaxy (ALE) for gas sensor applications, have been characterized by secondary ion mass spectrometry (SIMS). Quantification of the depth profile data has been carried out by preparing a series of ion implanted standards. Average concentrations determined by SIMS have been compared with Sb/Sn ratios obtained by X-ray fluorescence (XRF) spectrometry and proton induced X-ray emission (PIXE) spectrometry and have been found to be in good agreement. However, a detection limit of 5x10(18) at cm(-3) could only be obtained because of mass interferences. SIMS data show that the ALE technique can be used to produce a controllable growth and doping of thin films.

Journal Article↗
PubMed1995

Apolipoprotein E, dementia, and cortical deposition of beta-amyloid protein.

BACKGROUND: The epsilon 4 allele of apolipoprotein E has been associated with an increased risk of late-onset Alzheimer's disease. In a cohort of elderly subjects we prospectively investigated the relation between the apolipoprotein E genotype, dementia, and the accumulation of beta-amyloid protein in the cerebral cortex. METHODS: Autopsy involving neuropathological analysis and DNA analysis of frozen blood samples were performed in 92 of 271 persons who were at least 85 years of age, who had been living in Vantaa, Finland, on April 1, 1991, and who had died between that time and the end of 1993. All subjects had been tested for dementia. Apolipoprotein E genotyping was done with a solid-phase minisequencing technique. The percentage of the cortex occupied by methenamine silver-stained plaques was used as an estimate of the extent of beta-amyloid protein deposition. RESULTS: The frequency of the epsilon 4 allele was significantly higher in the subjects with Alzheimer's disease than in the subjects without dementia (30 percent vs. 8 percent, P < 0.001). There was a greater accumulation of beta-amyloid protein in the brain and more neurofibrillary tangles in the subjects with the epsilon 4 allele than in those without it (P < 0.001). The deposition of beta-amyloid protein varied according to the genotype in both the subjects with dementia and those without dementia: it was lowest in those with the epsilon 2/epsilon 3 genotype, intermediate in those with the epsilon 3/epsilon 3 genotype, and highest in those with the epsilon 3/epsilon 4 genotype. A single subject had the epsilon 4/epsilon 4 genotype and had dementia. CONCLUSIONS: The epsilon 4 allele of apolipoprotein E is significantly associated with Alzheimer's disease. Even in elderly subjects without dementia, the apolipoprotein E genotype is related to the degree of deposition of beta-amyloid protein in the cerebral cortex.

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