1. |
- Andersson, John, 1979-
(författare)
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Air pollution and dementia in a low exposure setting : the role of noise, olfaction, and theapoe gene
- 2023
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Previous research indicates an association between air pollution exposure, and risk of dementia. Still, a number of factors that may play a role in this association remain to be explored. In addition, while most studies on air pollution and brain health have taken place in highly exposed large urban areas, the studies included in this thesis are conducted in an area with relatively low levels of air pollution and road traffic noise.The overall aim of this thesis is to investigate possible mechanisms - more specifically the role of noise, olfaction and the APOE-ε4 allele - in the association between air pollution and dementia, in a low exposure area. Because olfactory deficits have been linked to air pollution, and can be an early sign of dementia, an additional aim is to examine associations between exposure to air pollution and olfactory function.Methods: Participants were drawn from the Betula project – a prospective cohort study – in Umeå, Sweden. Modelled data on concentrations of nitrogenoxides (NOx), fine particle matter (PM2.5) and levels of road traffic noise, were matched with participants residential address at baseline. PM2.5 levels at the day of testing were obtained from a measuring station in the vicinity of the test location. Data on dementia diagnoses, APOE status, olfactory functions, and covariates, were drawn from the Betula project. Dementia assessment was primarily based on medical records, and conducted by a geropsychiatrist. Odor identification was assessed using the Scandinavian Odor Identification Test, and odor detection threshold by “sniffin’ sticks”. APOE genotype was determined by DNA analyses of blood samples.Study I. Where there is pollution, there is also often noise. In addition, exposure to noise can increase the risk of dementia. The aim of study I was to investigate the individual and combined effect of noise and air pollution on risk of dementia. The results showed an association between NOx and dementia. However, noise from road traffic did not contribute to this association.Study II. Olfactory deficits can be an early sign of dementia and might also becaused by air pollution. Olfactory receptor cells in the nasal cavity are exposed to inhaled air, and the olfactory bulb is one of the areas of the brain most affectedby air pollution. The APOE-ε4 allele is important to consider, as it is a risk factor for both dementia and declining olfactory functions. The aim of study II was to investigate the role of olfaction and the APOE-ε4 allele in the association between air pollution and dementia. Stratified analyses showed that associations between PM2.5 and dementia persisted only among APOE-ε4 carriers, and those with poor odor identification ability.Study III. The olfactory system may be vulnerable to air pollution, and olfactory dysfunction is an early sign of dementia. In addition, the moderating effect of odor identification ability found in study II, could be explained by air pollution increasing the risk of olfactory functions and dementia independent of each other. Thus, the aim of study III was to investigate the associations between PM2.5 (both long term exposure, and concentrations on the day of testing), and odor identification and detection. A positive association was observed between longterm air pollution exposure and odor identification ability. No association was found between long term air pollution exposure and odor detection, or between short term exposure and either olfactory outcome.Conclusion: Low levels of long-term exposure to air pollution increases the risk of dementia. APOE-ε4 carriers, and those with poor odor identification ability, seem particularly vulnerable. No residual confounding from road traffic noisewas found, suggesting that air pollution is the main component in the association between traffic related exposures and dementia in low-exposure areas. The positive association between air pollution and odor identification might be explained by socioeconomic status, and the links between olfaction and semantic memory.
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2. |
- Hedman, Linnea, 1979-
(författare)
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Epidemiological studies of asthma and allergic diseases in teenagers : methodological aspects and tobacco use
- 2010
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Parental reports are often used in studies of asthma and allergic diseases in children. A change in respondent from parent to index subject usually occurs during adolescence. Little is known about the effects this change in method might have on the outcomes of a longitudinal study. Smoking is a major cause of respiratory symptoms among adults and environmental tobacco smoke (ETS) is a risk factor for asthma among children. Less is known about these associations among teenagers. In order to improve prevention of smoking, it is important to identify populations at risk of becoming smokers. The aim of this thesis were to 1) evaluate the methodological change from parental to self-completion of a questionnaire about asthma and allergic diseases, and 2) to study determinants for, and respiratory health effects of ETS and personal smoking in teenagers.In 1996, a longitudinal study of asthma and allergic diseases among schoolchildren started within the Obstructive Lung Disease in Northern Sweden (OLIN) studies. All children in first and second grades (aged 7-8 years) in three municipalities, Luleå, Kiruna and Piteå (n=3,525) were invited and 97% participated by parental completion of a questionnaire. The cohort has been followed with annual questionnaires until age 16-17 years and with high participation rates (>91%). From age 12-13 years, the teenagers were the respondents and questions about their tobacco use were included. In addition to the questionnaire completed by the teenagers at age 13-14 years, a questionnaire was also distributed to a random sample of 10% of the parents and 294 participated (84%). The parents and the teenagers reported a similar prevalence of asthma, respiratory symptoms, rhinitis, eczema and environmental factors. Two statistically significant differences were found: the teenagers reported a higher prevalence of wheezing during or after exercise (14% vs 8%, p<0.05), and having a dog in the home in the last 12 months (42% vs 29%, p<0.001). Answer agreement between parents and teenagers on questions about asthma was almost perfect with kappa values of 0.8-0.9. Corresponding kappa values for questions about respiratory symptoms and rhinitis were 0.3-0.6 and for eczema 0.5-0.6. Agreement about environmental factors varied from 0.2-0.9. Kappa values for parental smoking were 0.8-0.9. The risk factor pattern for allergic diseases was similar regardless of respondent, ie parent or teenager.The prevalence of smoking increased from 3% at 12-13 years to 6% at 14-15 years. Smoking was more common among girls, while the use of snus was more common among boys. Significant risk factors related to smoking among teenagers were smoking family members, female sex and living in an apartment. Having physician-diagnosed asthma did not prevent the teenagers from becoming smokers. Factors related to using snus were a smoking mother and male sex. Daily smokers aged 16-17 years (9%) reported a significantly higher prevalence of wheezing and physician-diagnosed asthma compared to non-smokers. There was a significant dose-response association with higher prevalence of wheeze among those who smoked ≥11 cigarettes per day compared to those who smoked ≤10 per day. In multivariate analyses, maternal environmental tobacco smoke exposure was a significant risk factor for ever wheeze and physician-diagnosed asthma at age 16-17 years, while daily smoking was a risk factor for current wheeze.In conclusion, the methodological change of questionnaire respondent from parent to index subject did not substantially alter the findings of this longitudinal study. There were significant sex differences in the tobacco use: smoking was more common among girls and snus was more common among boys. The most important factor related to tobacco use was presence of family members who smoke. Both maternal ETS exposure and personal smoking was associated with asthma and wheeze in adolescence. ETS was associated with lifetime symptoms but daily smoking was more strongly associated with current symptoms.
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3. |
- Sonntag-Öström, Elisabet, 1958-
(författare)
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Forest for rest : recovery from exhaustion disorder
- 2014
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Background Exhaustion disorder (ED) is a common mental and behavioural disorder which often leads to severe negative consequences for the individual and the society. Natural environments have positive effects on mental, physiological and attentional recovery in stressed persons, which encouraged us to test if forest visits could improve recovery from ED. The main objective of the thesis was to study if visits to different kinds of forest environments have positive health effects on patients suffering from ED, and if forest visits can be utilized for rehabilitation.Methods Participants in the MiniRest study (n=20) and the Pilot study (n=6) (Papers I and II) were recruited from the Stress Rehabilitation Clinic (SRC) at the University Hospital in Umeå. Participants in the randomised controlled study, ForRest (n=99) and the Interview study (n=19) (Papers III and IV) were recruited from both the SRC and the Swedish Social Insurance Agency in Umeå. The MiniRest study involved only female ED patients and focused on immediate mental, physiological and attention capacity effects in one urban and three forest environments. The Pilot study investigated the practical arrangements for the forthcoming ForRest study. Participants in the ForRest study were randomised into either a three-month forest rehabilitation group; A (forest visits twice a week/4 hours per day) or to a control condition; B. Both groups received Cognitive Behavioural Rehabilitation (CBR) at 24 occasions/once a week after the three-month study period. Preferences for forest environments, mental state and attention capacity were studied for group A only. Psychological health measurements and sick leave data were compared between the groups after (i) the forest rehabilitation and (ii) the CBR. The Interview study was conducted according to grounded theory methodology and consisted of 19 participants from group A to explore personal experiences from the forest rehabilitation. Data collection was implemented through questionnaires, medical records, physiological measurements, and interviews.Results Exposure to forest environments was associated with higher preference, more favourable mental state and physiological responses, and increased attention capacity compared to an urban environment (Paper I). Open and accessible forest environments were preferred (Papers I, II and III). Recovery from ED was found in both groups in the ForRest study, but there were no differences between the groups over time. In group A, positive effects on mental state and attention capacity were found during the forest visits. An interaction effect was found with more positive effects on mental state during spring compared to autumn (Paper III). Solitude, feelings of freedom and no demands were important for finding peace of mind during the forest visits. Moreover, easier access to peace of mind, reflective thinking and positive feelings were reported as the forest rehabilitation progressed (Papers II and IV).Conclusions Forest visits have restorative effects for ED patients through enhanced mental well-being, easier access to peace of mind, beneficial physiological reactions and increased attention capacity which support the use of forest environments in rehabilitation. However, forest rehabilitation tested in a randomised controlled trial did not improve recovery from ED. Potentially rehabilitation with CBR and forest visits integrated could be more effective and should be further investigated in nature-assisted rehabilitation for ED patients.
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4. |
- Högvall Nordin, Maria, 1962-
(författare)
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"Dom brukar jämföra det med en stridspilot" : en studie i organisationskommunikation
- 2006
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The focus of this dissertation is on how communication regarding work environment and work related risks can be understood from an organizational communication perspective. Based on a case study of communication about work environment and work related risks in the Swedish forest industry, the present study discusses institutional influences on organizational sense making processes. A central question has been how to understand the organizational field as a cultural and communicative arena where concepts and ideas connected with issues in the field are communicated between different actors.The empirical data was gathered using different methods. A questionnaire aiming at screening media habits and information gathering strategies of forest machine contractors was used. Based on information from that screening, mass media content was analysed, such as daily newspapers, trade press and advertisements for forest machines. Also, interviews with actors in the field were analysed thematically with respect to how to unveil hidden key symbols and cultural valuations of forest machine work, the work environment and how to handle work related risks in forest work. The key symbols that were identified to organise conceptions about forest work and occupational risks connected with it contained information about different attitudes towards how to handle risks and other problems in the work environment. Two main types of conceptions were identified, technologically oriented conceptions and person oriented conceptions.The analysis revealed a fragmented picture of forest work. Yet, the picture was more or less common to the organizational field as a whole. Building on institutional theory and theories of sense making, the study results in a deeper understanding of sense making in relation to work environmental issues by applying an organizational dimension to risk communication in an organizational field.
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5. |
- Olofsson, Jonas, 1978-
(författare)
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Odor identification in aging and dementia : Influences of cognition and the ApoE gene
- 2008
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Olfactory function is impaired in aging and dementia. The general aim of this thesis was to identify variables that predict olfactory function and dysfunction (assessed with an odor identification test) in middle-aged and elderly adults. The thesis investigated whether odor identification performance was associated with demographic variables, cognitive function, the ApoE gene, dementia, and other health-related variables. The ApoE-ε4 allele is associated with cognitive impairment and Alzheimer’s disease, the most common form of dementia. The studies included in this thesis used data from the Betula study, a large-scale, population-based prospective study on aging, memory, and health. Study 1 investigated demographic and cognitive predictors of odor identification ability in non-demented participants. The results showed that younger age, female sex, and high education contributed to better odor identification ability. Cognitive speed and vocabulary had a small additional influence. Study 2 included information about ApoE genotypes, dementia and other health-related variables. The results indicated that the ApoE-ε4 allele was associated with odor identification impairment among the elderly, but not middle-aged adults. Participants who were demented at the time of testing or became demented within five years after testing exhibited olfactory impairments. Interestingly, the age-related olfactory impairment in ε4-carriers was independent of clinical dementia within five years. In Study 3, decline in global cognitive status over a five-year test-retest interval was predicted in a sample of elderly participants. The major result was a three-way interaction reflecting that odor identification impairment, old age, in combination with the ε4 allele predicted a larger cognitive decline. However, odor identification impairment did not predict cognitive change in elderly who were non-carriers of the ε4 allele. Overall, the results indicate that odor identification impairment in elderly is related to ApoE-ε4, cognitive decline, and clinical and pre-clinical stages of dementia. Theoretical and practical implications of the results are discussed. Furthermore, it is proposed that in order to effectively predict clinical dementia or cognitive decline from olfactory assessment in the elderly, variables that mediate (e.g. neuropathology) or moderate (e.g. age) the associations between olfactory function, the ε4 allele, and dementia need to be further evaluated, preferably in studies using longitudinal assessment.
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6. |
- Schäfer Hackenhaar, Fernanda, et al.
(författare)
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Short leukocyte telomeres predict 25-year Alzheimer's disease incidence in non-APOE ε4-carriers
- 2021
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Ingår i: Alzheimer's Research & Therapy. - : BioMed Central (BMC). - 1758-9193. ; 13
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Tidskriftsartikel (refereegranskat)abstract
- Background: Leukocyte telomere length (LTL) has been shown to predict Alzheimer’s disease (AD), albeit inconsistently. Failing to account for the competing risks between AD, other dementia types, and mortality, can be an explanation for the inconsistent findings in previous time-to-event analyses. Furthermore, previous studies indicate that the association between LTL and AD is non-linear and may differ depending on apolipoprotein E (APOE) ε4 allele carriage, the strongest genetic AD predictor.Methods: We analyzed whether baseline LTL in interaction with APOE ε4 predicts AD, by following 1306 initially non-demented subjects for 25 years. Gender- and age-residualized LTL (rLTL) was categorized into tertiles of short, medium, and long rLTLs. Two complementary time-to-event models that account for competing risks were used; the Fine-Gray model to estimate the association between the rLTL tertiles and the cumulative incidence of AD, and the cause-specific hazard model to assess whether the cause-specific risk of AD differed between the rLTL groups. Vascular dementia and death were considered competing risk events. Models were adjusted for baseline lifestyle-related risk factors, gender, age, and non-proportional hazards.Results: After follow-up, 149 were diagnosed with AD, 96 were diagnosed with vascular dementia, 465 died without dementia, and 596 remained healthy. Baseline rLTL and other covariates were assessed on average 8 years before AD onset (range 1–24). APOE ε4-carriers had significantly increased incidence of AD, as well as increased cause-specific AD risk. A significant rLTL-APOE interaction indicated that short rLTL at baseline was significantly associated with an increased incidence of AD among non-APOE ε4-carriers (subdistribution hazard ratio = 3.24, CI 1.404–7.462, P = 0.005), as well as borderline associated with increased cause-specific risk of AD (cause-specific hazard ratio = 1.67, CI 0.947–2.964, P = 0.07). Among APOE ε4-carriers, short or long rLTLs were not significantly associated with AD incidence, nor with the cause-specific risk of AD.Conclusions: Our findings from two complementary competing risk time-to-event models indicate that short rLTL may be a valuable predictor of the AD incidence in non-APOE ε4-carriers, on average 8 years before AD onset. More generally, the findings highlight the importance of accounting for competing risks, as well as the APOE status of participants in AD biomarker research.
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7. |
- Schäfer Hackenhaar, Fernanda, et al.
(författare)
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Sixteen-year longitudinal evaluation of blood-based DNA methylation biomarkers for early prediction of Alzheimer’s disease
- 2023
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Ingår i: Journal of Alzheimer's Disease. - : IOS Press. - 1387-2877 .- 1875-8908. ; 94:4, s. 1443-1464
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Tidskriftsartikel (refereegranskat)abstract
- Background: DNA methylation (DNAm), an epigenetic mark reflecting both inherited and environmental influences, hasshown promise for Alzheimer’s disease (AD) prediction.Objective: Testing long-term predictive ability (>15 years) of existing DNAm-based epigenetic age acceleration (EAA)measures and identifying novel early blood-based DNAm AD-prediction biomarkers.Methods: EAA measures calculated from Illumina EPIC data from blood were tested with linear mixed-effects models(LMMs) in a longitudinal case-control sample (50 late-onset AD cases; 51 matched controls) with prospective data up to 16years before clinical onset, and post-onset follow-up. NovelDNAmbiomarkers were generated with epigenome-wide LMMs,and Sparse Partial Least Squares Discriminant Analysis applied at pre- (10–16 years), and post-AD-onset time-points.Results: EAA did not differentiate cases from controls during the follow-up time (p > 0.05). Three new DNA biomarkersshowed in-sample predictive ability on average 8 years pre-onset, after adjustment for age, sex, and white blood cell proportions(p-values: 0.022-<0.00001). Our longitudinally-derived panel replicated nominally (p = 0.012) in an external cohort (n = 146cases, 324 controls). However, its effect size and discriminatory accuracy were limited compared to APOE 4-carriership(OR = 1.38 per 1 SD DNAmscore increase versus OR= 13.58 for 4-allele carriage; AUCs = 77.2% versus 87.0%). Literaturereview showed low overlap (n = 4) across 3275 AD-associated CpGs from 8 published studies, and no overlap with ouridentified CpGs.Conclusion: The limited predictive value of EAA for AD extends prior findings by considering a longer follow-up time, andwith appropriate control for age, sex, APOE, and blood-cell proportions. Results also highlight challenges with replicatingdiscriminatory or predictive CpGs across studies.
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8. |
- Sorgenfrei, Simon, Docent, et al.
(författare)
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Mångreligiositet och sekularitet i svenskt polisväsende, vård, skola och offentlig förvaltning : en forskningsöversikt
- 2021
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Under de senaste decennierna har Sverige genomgått stora demografiska och politiska förändringar. Tillsammans har dessa inneburit att Sverige idag samtidigt är ett av Europas mest sekulariserade och mest mångreligiösa länder. Den snabba demografiska förändring Sverige har genomgått har ställt många inför nya, stora och i vissa fall skyndsamma kunskapsbehov samtidigt är forskningen om situationen delvis eftersatt. I denna rapport identifieras hur den nya situationen relaterar till det lagstadgade uppdrag som svenskt polisväsende, vård, skola och offentlig förvaltning har. Den forskning som gjorts inom dessa områden sammanfattas och de viktigaste forskningsbehoven identifieras.
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