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To describe representativeness in the Gothenburg H70 1930 Birth Cohort Study.Repeated cross-sectional examinations of a population-based study.Gothenburg, Sweden.All residents of Gothenburg, Sweden, born on specific birth dates in 1930 were invited to a comprehensive health examination at ages 70, 75, 79, 85 and 88. The number of participants at each examination was 524 at age 70, 767 at age 75, 580 at age 79, 416 at age 85, and 258 at age 88.We compared register data on sociodemographic characteristics and hospital discharge diagnoses between participants and (1) refusals, (2) all same-aged individuals in Gothenburg and (3) all same-aged individuals in Sweden. We also compared mortality rates between participants and refusals.Refusal rate increased with age. At two or more examination waves, participants compared with refusals had higher educational level, more often had osteoarthritis, had lower mortality rates, had lower prevalence of neuropsychiatric, alcohol-related and cardiovascular disorders, and were more often married. At two examination waves, participants compared with same-aged individuals in Gothenburg had higher education and were more often born in Sweden. At two examination waves or more, participants compared with same-aged individuals in Sweden had higher education, had higher average income, less often had ischaemic heart disease, were less often born in Sweden and were more often divorced.Participants were more similar to the target population in Gothenburg than to refusals and same-aged individuals in Sweden. Our study shows the importance of having different comparison groups when assessing representativeness of population studies, which is important in evaluating generalisability of results. The study also contributes unique and up-to-date knowledge about participation bias in these high age groups.

Older adults of today consume more alcohol, yet knowledge about the factors associated with different consumption levels is limited in this age group. Based on the data from a population-based sample (n = 1156, 539 men and 617 women) in The Gothenburg H70 Birth Cohort Study 2014–16, we examined sociodemographic, social, and health-related factors associated with alcohol consumption levels in 70-year-olds, using logistic regression. Total weekly alcohol intake was calculated based on the self-reported amount of alcohol consumed. Alcohol consumption was categorized as lifetime abstention, former drinking, moderate consumption (≤98 g/week), and at-risk consumption (>98 g/week). At-risk consumption was further categorized into lower at-risk (98–196 g/week), medium at-risk (196–350 g/week), and higher at-risk (≥350 g/week). We found that among the 1156 participants, 3% were lifetime abstainers, 3% were former drinkers, 64% were moderate drinkers, and 30% were at-risk drinkers (20% lower, 8% medium, 2% higher). Among several factors, former drinking was associated with worse general self-rated health (OR 1.65, 95% CI 1.08–2.51) and lower health-related quality of life (measured by physical component score) (OR 0.94, 95% CI 0.91–0.97), higher illness burden (OR 1.16, 95% CI 1.07–1.27), and weaker grip strength (OR 0.96, 95% CI 0.94–0.98). Higher at-risk drinkers more often had liver disease (OR 11.41, 95% CI 3.48–37.37) and minor depression (OR 4.57, 95% CI 1.40–14.95), but less contacts with health care (OR 0.32, 95% CI 0.11–0.92). Our findings demonstrate the importance of classifications beyond abstinence and at-risk consumption, with implications for both the prevention and clinical management of unhealthy consumption patterns in older adults.

Older adults of today consume more alcohol, yet knowledge about the factors associated with different consumption levels is limited in this age group. Based on the data from a population-based sample (

Population epidemiology is the science that deals with disorders and certain conditions at the population level, i.e. at the macro-level. In contrast to experimental studies, the scientist in epidemiology cannot manipulate conditions to make studies of associations as pure as possible. The science of epidemiological studies examines the occurrence of diseases, risk and protective factors for diseases, and the prognosis of different disorders and conditions in different populations. The capability approach is an ideal framework for epidemiological studies because it captures the dynamic and multiple processes involved in these types of studies, in relation to both time and space, as well as socioeconomic, psychological and biological factors. Determinants for common disorders and conditions include complex interactions among a multitude of factors acting between and within macro-, meso- and micro-levels during the life-course of an individual. In this chapter, we will discuss how the capability approach can be used in epidemiology in general, and in old age in particular, giving examples from specific conditions, such as cognitive function and dementia, depression, multimorbidity and functional ability, and non-modifiable and modifiable risk factors, such as genetics and nutrition. We conclude that the capability approach is a valuable tool in epidemiological studies. In these types of studies, capability is the final outcome of the dynamic interactions between a multitude of factors at the micro-, meso- and macro-levels leading to disorders and other conditions, which leads to restrictions in the individual’s ability to perform actions in order to reach goals he or she has reason to value.

Food frequency questionnaires (FFQ) are commonly used dietary assessment tools. The aim was to assess the relative validity of a 15-item FFQ, designed for the screening of poor dietary patterns with a validated diet history (DH). The study population was derived from the Gothenburg H70 Birth Cohort Studies. The DH registrations were harmonized in accordance with the FFQ frequencies. The agreement was assessed by Cohen’s kappa with corresponding confidence intervals (CI) for the frequency and categorical variables. Bland–Altman plots were used for the numeric variables. The study comprised data from 848 individuals (55.2% women). Overall, there was high agreement between the methods, with the exact and adjacent level of agreement over 80% for eight variables. The proportion attributed to the opposite frequency was fairly low for most of the frequency variables. Most of the kappa values were in fair or moderate agreement. The highest kappa values were calculated for the type of cooking fat (k = 0.68, CI = 0.63–0.72) and sandwich spread (k = 0.55, CI = 0.49–0.53), and the lowest for type of bread (0.13, CI = 0.07–0.20) and sweets (0.22 CI = 0.18–0.27). In conclusion, the FFQ showed overall good agreement compared with the DH. We, therefore, think it, with some improvements, could serve as a simple screening tool for poor dietary patterns., (This article belongs to the Special Issue Health Promotion in a Life Span Perspective)

PURPOSE: To investigate potential interactions between dietary patterns and genetic factors modulating risk for Alzheimer's disease (AD) in relation to incident dementia. METHODS: Data were derived from the population-based Gothenburg H70 Birth Cohort Studies in Sweden, including 602 dementia-free 70-year-olds (examined 1992-93, or 2000-02; 64% women) followed for incident dementia until 2016. Two factors from a reduced rank regression analysis were translated into dietary patterns, one healthy (e.g., vegetables, fruit, and fish) and one western (e.g., red meat, refined cereals, and full-fat dairy products). Genetic risk was determined by APOE ε4 status and non-APOE AD-polygenic risk scores (AD-PRSs). Gene-diet interactions in relation to incident dementia were analysed with Cox regression models. The interaction p value threshold was, Övriga forskningsfinaniserärer & strategiska forskningsprojekt:Open access funding provided by University of Gothenburg. SK was fnanced by grants from the Swedish state under the agreement between the Swedish government and the county councils, the ALF-agreement (ALFGBG-81392, ALF GBG-771071). [...] HZ is a Wallenberg Scholar supported by grants from the Swedish Research Council (2018-02532), the European Research Council (681712), Swedish State Support for Clinical Research (ALFGBG-720931), the Alzheimer Drug Discovery Foundation (ADDF), USA (201809-2016862), the AD Strategic Fund and the Alzheimer’s Association (ADSF-21-831376-C, ADSF-21-831381-C and ADSF-21-831377-C), [...] the Erling-Persson Family Foundation, [...] the European Union’s Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie grant agreement No 860197 (MIRIADE), and the UK Dementia Research Institute at UCL. IS was fnanced by grants from the Swedish state under the agreement between the Swedish government and the county councils, the ALF-agreement (ALF 716681), Stena Foundation, Swedish Research Council (11267, 2005-8460, 2007-7462, 2012-5041, 2015-02830, 2019-01096, 2013-8717, NEAR 2017-00639), [...] The Alzheimer’s Association Zenith Award (ZEN-01-3151), The Alzheimer's Association Stephanie B. Overstreet Scholars (IIRG-00-2159), The Bank of Sweden Tercentenary Foundation, Stiftelsen Söderström-Königska Sjukhemmet, [...] KB is supported by the Swedish Research Council (2017-00915), the Alzheimer Drug Discovery Foundation (ADDF), USA (RDAPB-201809-2016615), the Swedish Alzheimer Foundation (AF-742881), [...] the Swedish state under the agreement between the Swedish government and the County Councils, the ALF-agreement (ALFGBG-715986), the European Union Joint Program for Neurodegenerative Disorders (JPND2019-466-236), and the National Institute of Health (NIH), USA (grant 1R01AG068398-01). AZ was supported by the Swedish Alzheimer Foundation (AF-930582, AF-646061, AF-741361, AF-939988) [...].

Background Diet may be a modifiable factor for reducing the risk of Alzheimer's disease (AD). Western‐style dietary patterns are considered to increase the risk, whereas Mediterranean‐style dietary patterns are considered to reduce the risk. An association between diet and AD‐related biomarkers have been suggested, but studies are limited. Aim To investigate potential relations between dietary patterns and cerebrospinal fluid (CSF) biomarkers for AD among dementia‐free older adults. Methods Data were derived from the population‐based Gothenburg H70 Birth Cohort Studies, Sweden. A total of 269 dementia‐free 70‐year‐olds with dietary and cerebrospinal fluid (CSF) amyloid beta (Aβ42 and Aβ40), total tau (t‐tau), and phosphorylated tau (p‐tau) data were investigated. Dietary intake was determined by the diet history method, and four dietary patterns were derived by principal component analysis. A Western dietary pattern, a Mediterranean/prudent dietary pattern, a high‐protein and alcohol pattern, and a high‐total and saturated fat pattern. Logistic regression models, with CSF biomarker pathology (yes/no) as dependent variables, and linear regression models with continuous CSF biomarker levels as dependent variables were performed. The analyses were adjusted for sex, energy intake, body mass index (BMI), educational level, and physical activity level. Results The odds ratio for having total tau pathology (odds ratio [OR] 1.43; 95% confidence interval [CI] 1.02 to 2.01) and preclinical AD (Aβ42 and tau pathology; OR 1.79; 95% CI 1.03 to 3.10) was higher among those with a higher adherence to a Western dietary pattern. There were no other associations between the dietary patterns and CSF biomarkers that remained significant in both unadjusted and adjusted models. Discussion Our findings suggest that higher adherence to a Western dietary pattern may be associated with pathological levels of AD biomarkers in the preclinical phase of AD. These findings can be added to the increasing amount of evidence linking diet with AD and may be useful for future intervention studies investigating dietary intake in relation to AD.

To improve health care for older persons, we need to learn more about ageing, e.g. identify protective factors and early markers for diseases. The Gothenburg H70 Birth Cohort Studies (the H70 studies) are multidisciplinary epidemiological studies examining representative birth cohorts of older populations in Gothenburg, Sweden. So far, six birth cohorts of 70-year-olds have been examined over time, and examinations have been virtually identical between studies. This paper describes the study procedures for the baseline examination of the Birth cohort 1944, conducted in 2014–16. In this study, all men and women born 1944 on specific dates, and registered as residents in Gothenburg, were eligible for participation (n = 1839). A total of 1203 (response rate 72.2%; 559 men and 644 women; mean age 70.5 years) agreed to participate in the study. The study comprised sampling of blood and cerebrospinal fluid, psychiatric, cognitive, and physical health examinations, examinations of genetics and family history, use of medications, social factors, functional ability and disability, physical fitness and activity, body composition, lung function, audiological and ophthalmological examinations, diet, brain imaging, as well as a close informant interview, and qualitative studies. As in previous examinations, data collection serves as a basis for future longitudinal follow-up examinations. The research gained from the H70 studies has clinical relevance in relation to prevention, early diagnosis, clinical course, experience of illness, understanding pathogenesis and prognosis. Results will increase our understanding of ageing and inform service development, which may lead to enhanced quality of care for older persons. Electronic supplementary material The online version of this article (10.1007/s10654-018-0459-8) contains supplementary material, which is available to authorized users.

Objectives: Evidence suggests that diet could be a modifiable factor in the prevention of Alzheimer´s disease (AD). High quality dietary patterns, such as the Mediterranean diet, has been suggested ...

ESPEN 2018 Abstract Submission Topic: Nutritional epidemiology Abstract Submission Identifier: ESPEN18-ABS-1511 ALCOHOL AND DIETARY INTAKE AMONG 70-YEAR-OLDS – RESULTS FROM THE GOTHENBURG H70 BIRTH ...

There is a trade-off between the emissions of nitrogen oxides (NO x ) and of unburnt hydrocarbons and carbon monoxide (OGC and CO). Decreasing the excess air results in lower NO x emission but also increased emission of unburnt. The efficiency increases, as the excess air is decreased until the losses due to incomplete combustion become too high. The often-high NO x emission in today's pellet burners can be significantly reduced using well-known techniques such as air staging. The development of different chemical sensors is very intensive and recently sensors for CO and OGC have been introduced on the market. These sensors may, together with a Lambda sensor, provide efficient control for optimal performance with respect to emissions and efficiency. In this paper, results from an experimental parameter study in a modified commercial burner, followed by Chemkin simulations with relevant input data and experiments in a laboratory reactor and in a prototype burner, are summarised. Critical parameters for minimisation of NO x emission from pellet burners are investigated in some detail. Also, results from tests of a new sensor for unburnt are reported. In conclusion, relatively simple design modifications can significantly decrease NO x emission from today's pellet burners. Pell-Sim-dynamic model for forecasting storage and distribution of wood pellets

Bark pellets have been pyrolyzed in a fluidized bed reactor at temperatures between 700 and 1000C. Identified nitrogen-containing species were hydrogen cyanide (HCN), ammonia (NH3), and isocyanic acid (HNCO). Quantification of HCN and to some extent of NH3 was unreliable at 700 and 800C due to low concentrations. HNCO could not be quantified with any accuracy at any temperature for bark, due to the low concentrations found. Since most of the nitrogen in biomass is bound in proteins, various protein-rich model compounds were pyrolyzed with the aim of finding features that are protein-specific, making conclusions regarding the model compounds applica-ble for biomass fuels in general. The model compounds used were a whey protein isolate, soya beans, yellow peas, and shea nut meal. The split between HCN and NH3 depends on the compound and temperature. It was found that the HCN/NH3 ratio is very sensitive to temperature and increases with increasing temperature for all compounds, including bark. Comparing the ratio for the different compounds at a fixed temperature, the ratio was found to decrease with decreasing release of volatile nitrogen. The temperature dependence implies that heating rate and thereby particle size affect the split between HCN and NH3. For whey, soya beans, and yellow peas, HNCO was also quantified. It is suggested that most HCN and HNCO are produced from cracking of cyclic amides formed as primary pyrolysis products. The dependence of the HNCO/HCN ratio on the compound is fairly small, but the temperature dependence of the ratio is substantial, decreasing with increasing temperature. The release of nitrogen-containing species does not seem to be greatly affected by the other constituents of the fuel, and proteins appear to be suitable model compounds for the nitrogen in biomass.

When a solid fuel, such as coal, biomass or a mixture of these fuels, enters a hot fluidized bed, the volatile carbon and nitrogen compounds are released, while some nitrogen and carbon remains in the solid char. Volatile nitrogen can form reactive species such as NH3 , HCN and tar-nitrogen. These can react in the presence of oxygen to NO (and some N2 O). Some part of volatile nitrogen is always reduced to N2 . During combustion of the char residue, some part of the char-nitrogen forms NO (or N2 O) and the rest is converted to N2 . Usually the standard fuel analysis is not enough to allow for accurate NO emission predictions in large scale fluidized bed combustion. This paper presents NO formation tendency characterization results from novel laboratory measurements in a small-scale fluidised bed combustor. The laboratory results of this paper give a good insight into the distribution of fuel nitrogen between reactive and non-reactive (N2 ) volatile components and char-nitrogen. A NO formation tendency database is formed based on the results, including data on biomass-, waste-, peat- and coal-type fuels. The combustion test results show that the cumulative conversion of fuel nitrogen to NO under lean, non-staged fluidized bed combustion is 20–50% (850°C with O2 in excess). For biomass and peat, nearly all reactive nitrogen (forming NO) is released from the fuel during pyrolysis. NO formation during char combustion is significant with coal. With the help of the database, a reasonable estimate of the maximum non-staged NO emission in fluidized bed combustion can be obtained. Normally, air staging is utilized to reduce NO emissions. Effects of air-staging can be studied by means of modelling. In case of a BFBC boiler, the data can be used as input in the design or modelling of air staging for freeboard. For CFBC, the data can be used as input in the NO prediction where the once formed NO is further reduced by char carbon.Copyright © 2005 by ASME