| 1. |
- Jonsson, Ing-Marie, 1960-
(författare)
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Social and Emotional Characteristics of Speech-based In-Vehicle Information Systems : Impact on Attitude and Driving Behaviour
- 2009
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Modern vehicles use advanced information systems in vehicles to provide and control a wide variety of functions and features. Even modest vehicles today are equipped with systems that control diverse functions from air-conditioning to high quality audio/video systems.Since driving requires the use of eyes and hands, voice interaction has become more widely used by in-vehicle systems. Due to the technical complexity involved in voice recognition, focus has been on issues of speech ecognition. Speech generation is comparatively simple, but what effect does the choice of voice have on the driver? We know from human-human interaction that social cues of the voice itself influence attitude and interpretation of information. Introducing speech based communication with the car changes the relationship between driver and vehicle. So, for in-vehicle information systems, does the spoken voice matter?The work presented in this thesis studies the effects of the voice used by invehicle systems. A series of studies were used to answer the following questions: Do the characteristics of voices used by an in-vehicle system affect driver’s attitude? Do the characteristics of voice used by an in-vehicle system affect driver’s performance? Are social reactions to voice communication the same in the car environment as in the office environment?Results show that voices do matter! Voices trigger social and emotional effects that impact both attitude and driving performance. Moreover, there is not one effective voice that works for all drivers. Therefore an in-vehicle system that knows its driver and possibly adapts to its driver can be the most effective. Finally, an interesting observation from these studies is that social reactions to voice communication in the car are different than in the office, Similarity attraction, an otherwise solid finding in social science, did not hold all studies. It is hypothesized that this difference can be related to the different kinds of task demands when driving a car or working in an office environment.
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| 2. |
- Sundström, Johan, Professor, 1971-, et al.
(författare)
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Risk factors for subarachnoid haemorrhage : a nationwide cohort of 950 000 adults
- 2019
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Ingår i: International Journal of Epidemiology. - : Oxford University Press. - 0300-5771 .- 1464-3685. ; 48:6, s. 2018-2025
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Subarachnoid haemorrhage (SAH) is a devastating disease, with high mortality rate and substantial disability among survivors. Its causes are poorly understood. We aimed to investigate risk factors for SAH using a novel nationwide cohort consortium.METHODS: We obtained individual participant data of 949 683 persons (330 334 women) between 25 and 90 years old, with no history of SAH at baseline, from 21 population-based cohorts. Outcomes were obtained from the Swedish Patient and Causes of Death Registries.RESULTS: During 13 704 959 person-years of follow-up, 2659 cases of first-ever fatal or non-fatal SAH occurred, with an age-standardized incidence rate of 9.0 [95% confidence interval (CI) (7.4-10.6)/100 000 person-years] in men and 13.8 [(11.4-16.2)/100 000 person-years] in women. The incidence rate increased exponentially with higher age. In multivariable-adjusted Poisson models, marked sex interactions for current smoking and body mass index (BMI) were observed. Current smoking conferred a rate ratio (RR) of 2.24 (95% CI 1.95-2.57) in women and 1.62 (1.47-1.79) in men. One standard deviation higher BMI was associated with an RR of 0.86 (0.81-0.92) in women and 1.02 (0.96-1.08) in men. Higher blood pressure and lower education level were also associated with higher risk of SAH.CONCLUSIONS: The risk of SAH is 45% higher in women than in men, with substantial sex differences in risk factor strengths. In particular, a markedly stronger adverse effect of smoking in women may motivate targeted public health initiatives.
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| 3. |
- Barros, Guilherme, 1992-
(författare)
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Estimation of hazard ratios from observational data with applications related to stroke
- 2024
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The objective of this thesis is to examine some challenges that may emerge when conducting time-to-event studies based on observational data. Time-to-event (also called survival) is a setting that involves analyzing how different factors may influence the length of time until an individual experiences the event of interest. This type of analysis is commonly applied in fields such as medical research and epidemiology. In this thesis, which focuses on stroke, we are interested in the time to a recurrent stroke or the death of a patient who survived a first stroke.Hazard ratios are one of the main parameters estimated in time-to-event studies. Hazard ratios involve comparing the risk of experiencing the event between two groups, usually a treated group and an untreated group. They can also involve other factors, such as different age groups. Hazard ratios can be estimated from the data by using the Cox regression model.Observational data, in contrast to experimental data, involves data collected without any intervention or random assignment of treatment to the individuals. Confounders, that is, variables that distort or obscure the true relationship between treatment and outcome, are always present and need to be controlled for in observational studies.National registers are an important source of observational data. A national registry is a centralized database or system that collects, stores, and maintains information about a specific population or group of individuals within a country. Sweden is known for its detailed and complete national registers. In this thesis, data from the Swedish Stroke Register (Riksstroke) is used to study factors related to stroke.In time-to-event studies involving observational data, several challenges may arise for the researcher during data analysis. Some individuals may not experience the event during the observation period and thus the information about their time until the event is incomplete. These individuals are considered as censored. Some individuals may experience another event rather than the one of interest, a competing risk. Additionally, models must be properly constructed, with researchers selecting variables and determining the suitable functional form.Four papers are included in the thesis. Paper I demonstrates how to handle competing risks in survival analysis. The study involves comparing individuals with and without standard modifiable risk factors and their risks of a recurrent stroke or death using data from the Swedish Stroke Register.The estimation of marginal hazard ratios is a common theme in the other three papers. All involve simulation studies in order to extend methods and explore best practices when estimating marginal hazard ratios.Paper II explores non-parametric methods that can be used as alternatives to more traditional parametric methods when balancing datasets in order to estimate a marginal hazard ratio. A case study was also conducted using data from the Swedish Stroke Register involving the prescription of anticoagulants at hospital discharge after a stroke.Paper III is about how censoring affects marginal hazard ratio estimation, even with perfect balancing of the dataset. We study this issue, taking into consideration varying effect sizes and censoring rates. A procedure to attenuate the problem is also studied.Paper IV concerns covariate selection in the case of high-dimensional data. High-dimensional data involves cases in which the number of covariates in the study is comparable to the number of individuals, and therefore covariate selection methods are needed. In the paper, we explore some of these methods and suggest a best-performing procedure. As Paper II, Paper IV involves a case study of anticoagulant prescription using data from the Swedish Stroke Register.
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| 4. |
- Beer, Torfinn, 1992-
(författare)
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An epidemiological perspective on heart and lung weight in cardiac and intoxication deaths
- 2022
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The main purpose of a medico-legal autopsy is to determine the cause and manner of death. A forensic pathologist makes assessments of this using several sources of information, one of which is the discrepancy between measured organ weight and reference values. Of particular interest is the heart weight in heart disease and the weight of the lungs in fatal intoxications. In this thesis, a linear model of lung weight was created, but the model could at best explain only 13% of the variation in combined lung weight (Paper I). Unsurprisingly, this meant that the model was a poor definition of “normal” lung weight and could not be used to identify intoxication cases (Paper II). A ratio of lung weight to heart weight (LWHW ratio) also failed to differentiate intoxication cases from controls. The poor performance of these methods could plausibly have been due to fatal intoxications with only some substances being associated with increased lung weight, but an analysis showed that many common intoxicants were associated with heavier lungs than hanging deaths (Paper III). To establish heart weight references more applicable in a medico-legal autopsy population, a model of heart weight accounting for undiagnosed cardiac hypertrophy was created (Paper IV). The model showed that for a decedent of average the evidence that a was hypertrophic reached, substantial support at around 470 g.In conclusion, a definition of “heavy lungs” remains elusive. However, it seems to be a finding compatible with fatal intoxications with many substances and the low predictive value found may be due to study design. The heart weight model presented allows pathologists to assess the evidence of cardiac hypertrophy more easily than previously published models.
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| 5. |
- Darehed, David, 1986-
(författare)
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The impact of organizational and temporal factors on acute stroke care in Sweden
- 2020
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Background: Acute stroke carries a high risk of morbidity and death, but early treatment can improve outcomes. Intravenous stroke thrombolysis (IVT) is one such treatment, it is however time-sensitive and show better outcomes the sooner it is given. Most studies on time to IVT so far have looked at fixed time-intervals, and studies of short delays in clinical practice are relatively scarce. Another well-established treatment is managing acute stroke patients in stroke units (SU). Admission rates to a SU as first destination of hospital care have improved over time in Sweden. In the past decade however, the rates have leveled out at around 75-80% without further improvement. A hypothesis is that in-hospital overcrowding contributes. Previous studies have shown that outcomes after stroke differ between hospital types, and also vary depending on time of admission, with higher mortality seen for off-hours, weekend and winter admissions. The reasons behind temporal variations are not fully understood, but it has been proposed that environmental, patient-related and organizational factors contribute. The overall aim of this thesis was to study the effect of organizational factors on quality of care and outcomes after stroke, primarily focusing on the role of in-hospital overcrowding, in-hospital time to IVT and time of admission, while also studying differences between hospitals.Methods: All papers in this thesis were based on data from the Swedish stroke register (Riksstroke), a national quality register that holds data on patient related factors, acute care and outcomes. Paper I included 13,955 patient admissions from 14 hospitals in Region Norrbotten and Region Skåne from 2011-2014, enriched with data on in-hospital bed occupancy. Papers II-IV included all 72 Swedish hospitals caring for patients with acute stroke. Paper II included data from 2011-2015 (N=113,862), paper III from 2011-2016 (N=132,744) and paper IV from 2010-2017 (N=14,132). Analyses included descriptive statistics, unadjusted analyses and multivariable adjusted analyses.Results: We found that each percent increase in in-hospital bed occupancy above 85% decreased admission rates to a SU as first destination of hospital care by 1.5% (odds ratio (OR) 0.985, 95% confidence interval (CI) 0.978-0.992), with significant differences between hospitals. Admission rates were also lower off-hours, compared to on-hours (OR 0.73, 95% CI 0.70-0.75). Over time, admission rates to a SU as first destination of hospital care decreased in university hospitals, while they increased in specialized non-university hospitals and community hospitals. Each minute delay in door-to-needle time (DNT) decreased the odds of 90-day survival by 0.6% (OR 0.994, 95% CI 0.992-0.996), increased the odds of ICH within 36 hours by 0.3% (OR 1.003, 95% CI 1.000-1.006), and led to significantly higher odds of a worsening in functional outcomes at 3 months by 0.3-0.4%. DNT within 30 minutes was most likely daytime, and varied between hospital types. 90-day survival was lowest for patients admitted in January (81.5%), and highest for those admitted in May (84.1%) (OR 1.28, 95% CI 1.17-1.40).Conclusion: We found that in-hospital overcrowding decrease admission rates to a SU as first destination of hospital care, and that even short delays in DNT decreases survival, increases ICH complications and leads to a worsening in functional outcomes in routine clinical practice. We also found that quality of care varied depending on time of admission and between hospitals, indicating unequal care. Organizational differences should be accessible through quality improvement efforts aiming to implement robust local guidelines for in-hospital stroke treatment.
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| 6. |
- Eriksson, Marie, 1970-
(författare)
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Aspects on stroke outcome : survival, functional status, depression and sex differences in Riks-Stroke, the National Quality Register for Stroke Care
- 2008
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Stroke is a major cause of death and disability worldwide. In Sweden, about 30 000 strokes occur each year. The aim of this thesis was to analyse survival, functional outcome and self-reported depression after stroke, and to explore possible differences between men and women in stroke care and outcome. These studies were based on Riks-Stroke, the Swedish national quality register for stroke care. Information on background variables and treatment were collected during the hospital stay. The patient’s situation and outcome after stroke were followed-up after 3 months. Long term survival was retrieved from the Swedish Population Register (Folkbokföringen). Possible sex-differences in stroke care and outcome 3 months after stroke were explored in 24 633 strokes, registered during 2006. In conscious patients, the proportions treated at stroke units were similar for men and women. Men and women had equal chance to receive thrombolytic therapy or secondary prevention with oral anticoagulants. Compared to men, women were less likely to develop pneumonia, but more likely to experience deep venous thromboses and fractures during hospital stay. Women had worse 3-month survival and functional outcome, differences that were explained by their higher age and impaired level of consciousness on admission. Women felt more depressed and perceived their health as worse than men did. Women were also less satisfied with the care they had received in the hospital. The agreement between self-reported functional outcome 3 months after stroke and the commonly used modified Rankin Scale (mRS) was explored in 555 stroke survivors from 4 hospitals during May-September 2005. Riks-Stroke’s self-reported questions classified 76% of the patients into correct mRS grade. The association between functional outcome 3 months after stroke and 3-year survival was assessed in 15 959 men and women who had had a stroke during 2001-2002. Patients with estimated mRS grades 3, 4 and 5 had hazard ratios for death of 1.7, 2.5 and 3.8, respectively, as compared with patients with lower grades, 0-2. Depressed mood, male sex, high age, diabetes, smoking, antihypertensive therapy at onset and atrial fibrillation were also identified as predictors of poor survival. Self-reported depression 3 months after stroke and use of antidepressants were analysed in 15 747 stroke survivors from 2002. Fourteen percent felt depressed 3 months after stroke. Female sex, age <65, previous stroke, living alone or in institution, or being dependent in activities of daily living (ADL) were factors associated with self-reported depression. At the follow-up, 22% of the men and 28% of the women were using antidepressant medication, which were approximately twice as many as in the general population. Still, 8% of all patients in Riks-Stroke reported depressive mood but no treatment with antidepressants. In conclusion, men and women with stroke in Sweden experience similar treatment and outcome in most aspects. Patient-reported functional outcome can be reliably transformed to a standard disability scale. Impaired functional outcome three months after stroke is an independent predictor of poor long-term survival. Depressive mood is common after stroke and is associated with poor survival and impaired functional outcome.
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| 7. |
- Flinkfeldt, Marie, 1982-
(författare)
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Legitimacy Work : Managing Sick Leave Legitimacy in Interaction
- 2016
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- This thesis studies how sick leave legitimacy is managed in interaction and develops an empirically driven conceptualization of ‘legitimacy work’. The thesis applies an ethnomethodological framework that draws on conversation analysis, discursive psychology, and membership categorization analysis. Naturally occurring interaction is examined in two settings: (1) multi-party meetings at the Swedish Social Insurance Agency, in which participants assess and discuss the ‘status’ of the sick leave and plan for work rehabilitation; (2) peer-based online text-in-interaction in a Swedish forum thread that gathers people on sick leave.The thesis shows how mental states, activities and alternative categories function as resources for legitimacy work. However, such invocations are no straight-forward matter, but impose additional contingencies. It is thus crucial how they are invoked. By detailed analyses of the interaction, with attention to aspects such as lexicality and delivery, the thesis identifies a range of discursive features that manage sick leave legitimacy. Deployed resources are also subtle enough to be deniable as legitimacy work, that is, they also manage the risk of an utterance being seen as invested or biased.While legitimate sick leave is a core concern for Swedish policy-making, administration, and public debate on sick leave, previous research has for the most part been explanatory in orientation, minding legitimacy rather than studying it in its own right. By providing detailed knowledge about the legitimacy work that people on long-term sick leave do as part of both institutional and mundane encounters, the thesis contributes not only new empirical knowledge, but a new kind of empirical knowledge, shedding light on how the complexities of sick leave play out in real-life situations.Traditional sociological approaches have to a significant extent treated legitimacy as an entity with beginnings and ends that in more or less direct ways relate to external norms and cognitive states, or that focus on institutions, authority or government. By contrast, the herein emerging concept ‘legitimacy work’ understands legitimacy as a locally contingent practicality – a collaborative categorially oriented accomplishment that is integral to the interactional situation.
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| 8. |
- Gimbler Berglund, Ingalill
(författare)
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Developing guidelines in nursing care of children with Autism Spectrum Disorder in high technology health care settings
- 2017
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Introduction. The high technology environment such as a radiology and anaesthesia department in a typical health care setting can many times be a frightening environment for children. Children with neurodevelopmental disorders, such as Autism Spectrum Disorder (ASD), have problems with communication and social interaction. They are dependent on routines and can have higher sensitivity to sensory stimuli than other children. These children are one group who constitutes special challenges in reducing anxiety and creating participation in a high technology environment. This can make them prone to frightening encounters in health care settings if not cared for with special consideration.Aim: The overall aim of this thesis was to audit and enhance the care of children in a high technology environment in the health care system with a focus on children with Autism Spectrum Disorder.Methods: A descriptive design was used with both qualitative and quantitative methods. In Study I, 32 nurse anaesthetists were interviewed to explore the actions and experiences of caring for children in a high technology environment using a qualitative method, known as the Critical Incident Technique (CIT). In the two following studies (Study II, III) a cross-sectional design was used and two national surveys were performed to obtain knowledge on the status in Sweden regarding the care of children with ASD in high technology environments. Sixty-eight anaesthesia departments, 38 paediatric departments and 86 radiology departments responded to the survey. Descriptive statistic was used for the answers apart from the comments part of the questionnaire where qualitative content analysis was used. Due to the limited existence of guidelines in these environments, the creation ofevidence-based guidelines was performed in Study IV, using a Delphi method. The Delphi study was based on information gleaned from the previous studies and from the literature, and 21 experts identified in Study II and III were the expert panel developing the guidelines.Result: Nurses identified children with special needs such as children with ASD as a vulnerable group in a high technology environment (Study I). Seven departments in the anaesthesia context had guidelines for caring for children with ASD in the perioperative context. In the other departments, the care of children with ASD was dependent on the knowledge of the nurse presently working there (Study II). None of the radiology departments in Sweden had guidelines on how to care for children with ASD going through a radiographic examination without anaesthesia (Study III). As a result of Study I, II and III, the need for structured guidelines for caring for children with ASD in a high technology context was identified and a set of guidelines and a checklist was created. The guidelines relate to the organisational structure for the care of children with deficits in social interaction, communication, sensory sensitivity and dependence on routines. The checklist relates to gleaning information about the specific child to be able to give person-centred care based on the specific characteristic of the child (Study IV).Conclusion: Nurses working in a high technology environment in health care have diverse experiences of preventing anxiety in children with ASD coming for a challenging procedure. There are a limited number of evidence-based guidelines to decrease anxiety and to create participation in this group ofchildren. Evidence-based guidelines were created as a tool for enhancing person-centred care in a high technology environment for this group of children. The fact that several problems are assembled under one disorder makes ASD a useful condition to have as a basis for formulating national guidelines. Guidelines that cater for the care of children with ASD in a high technology environment using a person-centred approach may also extend to the care for children with other neurodevelopmental disorders that exhibit some of the same problems as children with ASD.
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| 9. |
- Björk, Marie, 1963-
(författare)
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Att främja elevers teoretiska utforskande av bassystemet : En undervisningsutvecklande studie i matematik på mellanstadiet
- 2023
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Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Den här licentiatuppsatsen handlar om hur en undervisning kan främja elevers förståelse av tiobassystemet genom att de bjuds in till en undervisning där de kan delta i ett kollektivt utforskande av bassystemet, som en övergripande nivå av tiobassystemet. Syftet är att exemplifiera och diskutera hur en undervisning, som främjar elevernas möjligheter att utveckla ett tänkande om tiobassystemet på en generell eller övergripande nivå, kan utformas. Vidare är syftet att studera vad i en undervisning, designad enligt principerna för lärandeverksamhet, som kan förstås som förebyggande i specialpedagogisk mening.Studien bygger på resultatet av två artiklar med följande frågeställningar: 1) Vilka aspekter i uppgifternas utformning och genomförande främjar elevers möjligheter att pröva relationen mellan olika bastal och övergång till successivt större respektive mindre talenheter? 2) Vad i elevernas resonemang och arbete med speciellt designade uppgifter kan ses som tecken på teoretiskt tänkande om bassystemet?Learning study har använts som forskningsramverk och genererat data för uppsatsens två artiklar. Learning studyn genomfördes i årskurs 4, tillsammans med tre matematiklärare. Design och analys är inspirerad av El’konins och Davydovs matematiska program och några principer från lärandeverksamhet. Analysen i de bägge artiklarna är genomförd med stöd av teoretiska principer för lärandeverksamhet. Datamaterialet består av videoinspelningar från tre lektioner (totalt cirka 420 minuter), transkriptioner och datasammanställningar av uppgifter, transkriptioner och anteckningar från utvärderingarna i det iterativa arbetet med lektionerna.Resultatet består av tre aspekter som behöver synliggöras genom uppgifternas utformning och genomförande för att eleverna ska kunna arbeta teoretiskt med bassystemets struktur: (1) Bastalet, (2) Tal som mätetal, och (3) Talenheternas representationer. Eleverna behöver urskilja aspekterna för att kunna identifiera att det fattas en lämplig talenhet och för att kunna pröva och reflektera över relationen mellan bastalet och övergången till successivt större respektive mindre talenheter i olika baser. Resultatet består också av ett antal exempel på tecken på teoretiskt tänkande inom tre identifierade kategorier: 1) basens funktion för det värde som siffrorna anger i talet, 2) positionsväxling, och (3 entalet som ett av en kvantitet. I analysen har Davydovs definition av teoretiskt tänkande, som något som kan komma till uttryck i form av teoretisk reflektion, analys och planering samt reproduktion av grundläggande principer för ett specifikt ämnesinnehåll, använts.Resultatet ger ett bidrag till den matematikdidaktiska forskningen och till den specialpedagogiska forskningen med inriktning mot matematik genom beskrivningar av de tre aspekterna och av tecken på teoretiskt tänkande. Vidare kan beskrivningarna av uppgifternas utformning och genomförande användas i undervisning och i fortsatta studier.I diskussionen behandlas hur en undervisning kan utformas som främjar elevernas möjligheter att utveckla ett teoretiskt tänkande om bassystemet. Diskussionen behandlar också vad i en undervisning designad enligt principerna för lärandeverksamhet som kan förstås som förebyggande i specialpedagogisk mening genom att skapa möjligheter för elever att redan tidigt i grundskolan kollektivt utforska och förstå hela positionssystemet som en struktur. Slutligen diskuteras implikationer för specialundervisning och studiens bidrag.
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| 10. |
- Byhamre, Marja Lisa, 1981-
(författare)
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Snus use and mortality : associations, potential mechanisms, and socioeconomic aspects
- 2022
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Snus is a smokeless tobacco product made of a moist powder of ground tobacco. It is used mainly in the Nordic countries, although increasingly popular internationally. The Swedish snus tradition dates back to the seventeenth century, and it is now used daily by about 23% of the male and 6% of the female population. Snus contains high levels of nicotine as well as carcinogenic substances and microorganisms that could potentially cause adverse health effects. The physiological effects of snus use include acutely raised blood pressure and heart rate, and increased cardiac oxygen demand, while the psychological response results in alertness and anxiety reduction. The high nicotine content causes rapid onset of addiction. Previous research on snus use and health is largely inconclusive, but indicates increased risks of all-cause, cardiovascular and cancer mortality. This thesis aimed to further investigate the health effects of snus use, with a focus on mortality, potential underlying mechanisms, and the impact of socioeconomic factors. Four original papers form the base of this thesis. The first study was performed on a pooled dataset of eight Swedish cohorts (The Swedish Collaboration on Health Effects of Snus use), including over 169 000 men. We found an increased risk of all-cause (HR 1.28, 95% CI 1.20; 1.35), cardiovascular, and other cause mortality, and indications of raised cancer mortality. The second study was set within an interventional program in northern Sweden (Västerbotten Intervention Programme) and included 46 000 men and women. It showed increased mortality overall (estimates similar to first study), from cardiovascular diseases, and external causes (e.g., accidents and suicide) that remained after controlling for socioeconomic status. We found these associations in groups of varying socioeconomic background (e.g., both basic education and high-income groups), suggesting that increased mortality risks among snus users are not restricted to certain socioeconomic groups. Studies three and four investigated potential underlying mechanisms that might contribute to increased mortality among snus users, including established cardiometabolic risk factors in study three (the metabolic syndrome and its components: obesity, hypertension, type 2-diabetes and abnormal blood lipids) and more novel risk factors in study four (low-grade inflammation, low vitamin D-concentrations, and altered iii testosterone levels). The analytical samples were drawn from a long- term follow-up study of around 900 16-year-olds in a municipality in northern Sweden (Northern Sweden Cohort, study three) and more than 6 000 participants in another population-based cohort (the Northern Sweden MONICA study, study four). We found no associations between snus use and established cardiometabolic risk factors, but there was evidence of lower concentrations of inflammatory and vitamin D-status biomarkers in both men and women, and higher testosterone concentrations in men who were currently using snus. We conclude that snus use is associated with increased all-cause and cardiovascular mortality, and to death by other causes, that may be restricted to external causes. Cancer mortality may also be increased among snus users. The associations cannot be fully explained by differences in socioeconomic status among snus users and non-users. Established cardiometabolic risk factors do not seem to be the main mechanisms behind these associations. Lower inflammatory biomarker levels among snus users may serve as a protective factor, while lower vitamin D-concentrations and increased testosterone levels may be part of an underlying mechanism linking snus use to increased mortality. Future research should focus on the health consequences of snus use among women, on other possible links between snus use and death, and on mortality in different cancers among users of snus. The health consequences of dual use of snus and cigarettes should also be assessed.
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