| 1. |
- Mubanga, Mwenya
(författare)
-
Dog Ownership and Cardiovascular Disease
- 2018
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The relationship between pet ownership and human health has been studied extensively; however, the effect of dog ownership on human health has had conflicting results. The overall aim of this research project was to investigate the impact of dog ownership, and the death of the dog, on human cardiovascular health and all-cause mortality.Study I was a population-based study investigating the association between dog ownership with the risk of cardiovascular disease (CVD) and death. Of 3,432,153 individuals included, dog ownership (13.1%) was associated with a lower risk of CVD- and all-cause death by 23% and 20%, respectively. In single-person households, there was an inverse association between dog ownership and incident CVD, as well as a stronger inverse association with CVD-death and all-cause death.Study II was a population-based study investigating the association between dog ownership and initiation of treatment for cardiovascular risk factors in 2,026,865 adults. Dog ownership (14.6%) was associated with a slightly elevated risk of initiating treatment (2%) for hypertension and dyslipidaemia, but not for diabetes mellitus. However, some evidence for residual confounding was found.Study III investigated the risk of death after hospitalization for a first-ever acute myocardial infarction (n=181,696) or first-ever ischemic stroke (n=157,617) in two population-based cohorts. Dog ownership was associated with a 20% to 24% lower risk of all-cause mortality and CVD-death, respectively.In Study I-III, ownership of hunting breed dogs was associated with the lowest risk of the outcomes, while owning dogs of mixed pedigree was associated with worse cardiovascular health.Study IV found evidence of an increased risk of CVD after the loss of a life-insured pet (dog or cat; n=147,251) during the first week, 3-6 months after and 6-12 months after pet-loss.This thesis has used the Swedish population and health registers to investigate the relationship between various aspects of dog ownership and cardiovascular risk. By using defined, quantifiable end-points and robust statistical methods, this project has made an important contribution to the body of research underlying the positive relationship between dog ownership and cardiovascular health, paving the way for further research into causal mechanisms.
|
|
| 2. |
- Olsson, Erika, 1970-
(författare)
-
Diet and common neurological disorders: cohort studies on dementia, Parkinson’s disease, and stroke
- 2021
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Risk factors for dementia, Parkinson’s disease, and stroke have been widely studied but there are still research gaps concerning the role of diet for the development of these diseases. The overall aim of this thesis was to investigate whether various aspects of diet are associated with common disorders and diseases in the brain. Paper I and II are based on the Uppsala Longitudinal Study of Adult Men (ULSAM). Paper III and IV are based on the Swedish Mammography Cohort (SMC) and the Cohort of Swedish Men (COSM). In paper I, we investigated the associations between three different dietary patterns and incidence of Alzheimer’s disease (AD), dementia, and cognitive impairment. We observed no associations between adherence to the Healthy Diet Indicator and any of the outcomes studied, or between adherence to a Mediterranean-like diet (mMDS) and AD or dementia. There was a tendency towards a lower risk of cognitive impairment with higher adherence to the mMDS, and a weak association between adherence to a Low Carbohydrate High Protein score and higher risk of all-type dementia. Overall, there were no strong associations with the studied dietary patterns and development of dementia or cognitive impairment. In paper II, we found no associations of vitamin D measured as vitamin D intake, plasma 25-hydroxyvitamin D concentrations, or a vitamin D synthesis genetic risk score with incident AD, vascular dementia, dementia, or performance in the Mini-Mental State Examination.In paper III, we observed a weak higher risk of PD associated with milk consumption but there was no dose-response relationship. Thus, this association needs to be interpreted with caution. Fermented milk intake was not associated with PD.In paper IV, we found that a higher long-term milk consumption based on repeated measures of intake was not associated with total stroke, weakly and non-linearly associated with lower risk of cerebral infarction and higher risk of hemorrhagic stroke. Fermented milk consumption was not associated with any stroke type. Our results highlight the importance of repeated measurements of food intake, separate analyses of milk and fermented milk consumption, and to study stroke types separately.Despite the lack of strong associations, the findings of this thesis have increased our knowledge about the potential role of overall diet, vitamin D, and milk and fermented consumption in the prevention or development of common neurodegenerative diseases and stroke.
|
|
| 3. |
- Leavy, Breiffni, 1977-
(författare)
-
Fall-Related Hip Fracture : Predisposing and Precipitating Factors
- 2015
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- A physically inactive lifestyle is a predisposing risk factor for fall-related hip fracture. The circumstances, or precipitating factors, surrounding hip fractures are, however, not well understood, a factor of relevance for Swedish adults who have one of the highest hip fracture risks in the world. The aims of this thesis, therefore, were: to explore perceptions of physical activity (PA) among older adults, to describe the circumstances surrounding hip fracture events and the health characteristics of those who experience them.Four observational studies were conducted involving qualitative, epidemiological and mixed method designs. Participants in study I were recruited from community settings in Stockholm and Dublin (n=30). Studies II-IV (sample sizes, n=484, n=125, n=477) were based on a population-based sample of people admitted to Uppsala University hospital due to hip fracture. Study IV also incorporated the background population of Uppsala county in 2010 (n=117 494).Analysis of PA perceptions in study I revealed that PA which is functional nature is perceived as most meaningful among certain participants. The uptake of PA in later years was a means of creating a new self-identify and being active in outdoor environments was an important culture-specific motivator to PA among Swedish participants. Analysis of hip fractures patterns in studies II-III showed that: hip fractures among psychotropic drug users were twice as likely to occur during night-time hours compared to those occurring among people not receiving these drugs. Additionally, the fall-related hip fractures of community dwellers with poorest health and function tended to occur indoors during positional changes. In study IV, all categories of disease (according to the International Classification of Diseases, 10th Revision) were seen to be positively associated with hip fracture. Cardiovascular disease and previous injury (including previous fracture) posed the highest relative and absolute fracture risks.Detailed investigation of hip fracture circumstances reveal patterns in health and functional characteristics, which provide information regarding predisposing and precipitating factors for these events. This knowledge, in combination with findings regarding PA perceptions, can be used when identifying individuals at high risk for hip fracture and when tailoring fracture prevention at an individual level to those at risk.
|
|
| 4. |
- Byberg, Liisa, 1972-
(författare)
-
Plasminogen Activator Inhibitor-1 and the Insulin Resistance Syndrome
- 2002
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- In this thesis, different aspects of the insulin resistance syndrome in relation to plasminogen activator inhibitor-1 (PAI-1) activity are investigated in a longitudinal population-based study. Participants were men investigated at ages 50 and 70 with follow-up data on mortality.High PAI-1 activity was associated with low insulin sensitivity, high concentrations of serum triglycerides, high body mass index and high waist/hip ratio, independently of each other and of potential confounders. Low birth weight predicted high blood pressure, insulin resistance, truncal obesity and high PAI-1 activity but not the abdominal obesity or dyslipidaemia present in the insulin resistance syndrome. Increased physical activity level between 50 and 70 years of age, in the absence of active intervention, was associated with improved glucose, insulin, proinsulin and lipoprotein metabolism. Insulin and proinsulin seemed to be important factors that mediate much of the association between a sedentary lifestyle and increased risk of cardiovascular disease. The reported dietary intake of both mono- and polyunsaturated fatty acids was positively associated with PAI-1 activity, whereas saturated fatty acid intake displayed no association. The associations present between PAI-1 activity and the fatty acid proportions in serum cholesterol esters were partly influenced by factors related with the insulin resistance syndrome.This thesis provides further knowledge to the epidemiological view of the interrelations of the insulin resistance syndrome, PAI-1, birth weight, and lifestyle factors as physical activity and dietary habits. PAI-1 is a part of the insulin resistance syndrome and is associated both with modifiable and non-modifiable factors related with this syndrome.
|
|
| 5. |
- Byberg, Liisa, et al.
(författare)
-
Total mortality after changes in leisure time physical activity in 50 year old men : 35 year follow-up of population based cohort
- 2009
-
Ingår i: British Journal of Sports Medicine. - : BMJ Publishing Group Ltd. - 0306-3674 .- 1473-0480. ; 338, s. b688-
-
Tidskriftsartikel (refereegranskat)abstract
- Objective: To examine how change in level of physical activity after middle age influences mortality and to compare it with the effect of smoking cessation.Design: Population based cohort study with follow-up over 35 years.Setting: Municipality of Uppsala, Sweden.Participants: 2205 men aged 50 in 1970-3 who were reexamined at ages 60, 70, 77, and 82 years.Main Outcome Measure: Total (all cause) mortality.Results: The absolute mortality rate was 27.1, 23.6, and 18.4 per 1000 person years in the groups with low, medium, and high physical activity, respectively. The relative rate reduction attributable to high physical activity was 32% for low and 22% for medium physical activity. Men who increased their physical activity level between the ages of 50 and 60 continued to have a higher mortality rate during the first five years of follow-up (adjusted hazard ratio 2.64, 95% confidence interval 1.32 to 5.27, compared with unchanged high physical activity). After 10 years of follow-up their increased physical activity was associated with reduced mortality to the level of men with unchanged high physical activity (1.10, 0.87 to 1.38). The reduction in mortality associated with increased physical activity (0.51, 0.26 to 0.97, compared with unchanged low physical activity) was similar to that associated with smoking cessation (0.64, 0.53 to 0.78, compared with continued smoking).Conclusions: Increased physical activity in middle age is eventually followed by a reduction in mortality to the same level as seen among men with constantly high physical activity. This reduction is comparable with that associated with smoking cessation
|
|
| 6. |
- Karamanis, Georgios
(författare)
-
Gender dysphoria : Insights on etiology and outcomes
- 2023
-
Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Gender Dysphoria (GD) is defined as significant distress or impairment caused by the discrepancy between an individual's experienced gender and the sex assigned at birth. This work explores the etiology and outcomes of GD through two studies. The first assesses its prevalence in different twin categories, and the second examines the incidence of idiopathic intracranial hypertension (IIH) in individuals undergoing gonadotropin-releasing hormone analogue (GnRHa) treatment for GD.The first study utilizes a population-based approach to analyze the prevalence of GD in twins, using data from a Swedish population-based cohort collected over a 16-year period. The objective is to assess the influence of genetic and environmental factors on the development of GD by comparing its prevalence in different-sex twins, same-sex twins, and non-twin siblings. The results indicate a higher prevalence of GD in different-sex twins and suggest a potential influence of intrauterine factors in the development of GD, necessitating further examination of current genetic and environmental theories.The second study focuses on evaluating the occurrence of IIH in individuals undergoing treatment with GnRHa for GD in Sweden between 2006 and 2016. The study did not observe any cases of IIH within the studied cohort. While better-powered studies are needed to clarify any potential association between GnRHa and IIH, the study results do not present substantial evidence to support this association.
|
|
| 7. |
- Ludvigsson, Jonas F., 1969-, et al.
(författare)
-
Adaptation of the Charlson Comorbidity Index for Register-Based Research in Sweden
- 2021
-
Ingår i: Clinical Epidemiology. - : Dove Medical Press Ltd.. - 1179-1349 .- 1179-1349. ; 13, s. 21-41
-
Tidskriftsartikel (refereegranskat)abstract
- Purpose: Comorbidity indices are often used to measure comorbidities in register-based research. We aimed to adapt the Charlson comorbidity index (CCI) to a Swedish setting.Methods: Four versions of the CCI were compared and evaluated by disease-specific experts.Results: We created a cohesive coding system for CCI to 1) harmonize the content between different international classification of disease codes (ICD-7,8,9,10), 2) delete incorrect codes, 3) enhance the distinction between mild, moderate or severe disease (and between diabetes with and without end-organ damage), 4) minimize duplication of codes, and 5) briefly explain the meaning of individual codes in writing.Conclusion: This work may provide an integrated and efficient coding algorithm for CCI to be used in medical register-based research in Sweden.
|
|
| 8. |
- Mitchell, Adam
(författare)
-
Insights into the Effects of Type 2 Diabetes on Bone Health
- 2020
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Individuals with type 2 diabetes mellitus (T2DM) have an increased risk of hip fracture, despite a stable or even greater bone mineral density (BMD). Bone area is linked to hip fracture risk independent of BMD and smaller bone area has been reported in T2DM subjects at the radius and tibia, but information at the hip is lacking. The Mediterranean diet is associated with a lower risk of hip fracture yet the mechanisms are unclear. The diet’s effect on T2DM status may be a possible mechanism. This thesis aims to discern the effects fasting glucose levels and T2DM have on bone.In paper I, clinical cut offs of fasting glucose used to define T2DM, were used to explore the association with BMD, bone area and bone turnover markers in the Swedish mammography cohort clinical (SMCC) and the Uppsala longitudinal study of adult men (ULSAM). T2DM was associated with greater BMD yet lower bone area at the total hip when compared to those without T2DM. T2DM was also associated with lower levels of bone turnover markers.In paper II, a Mendelian randomisation (MR) study was used to assess the potential causal effects of genetically predicted fasting glucose concentrations on bone area and BMD in partici-pants from SMCC, the prospective investigation in the vasculature of Uppsala seniors (PIVUS) and ULSAM. Results suggest an increase in genetically predicted fasting glucose concentrations may be a causal risk factor for lower bone area and possibly greater BMD.In paper III, the association between T2DM status and change in bone area and BMD over 8 years, was analysed in the SMCC, PIVUS and ULSAM. Those with incident T2DM had a lesser expansion in bone area at the total hip compared to those without T2DM.In paper IV, causal inference mediation analyses were used to estimate the direct effect of Mediterranean diet on the risk of hip fracture and the possible mediating effects of T2DM and BMI in the Swedish mammography cohort (SMC) and the cohort of Swedish men (COSM). Results showed a direct effect of the Mediterranean diet on the risk of hip fracture but ruled out the effects of T2DM and BMI as major mediators.In summary, T2DM and fasting glucose were associated with lower bone area at the hip. This may provide important mechanistic evidence as to why those with T2DM have a greater risk of hip fracture. We cannot rule out mediation or counteracting effects but there is an effect of Medi-terranean diet on hip fracture that does not go through T2DM and BMI.
|
|
| 9. |
- Mubanga, Mwenya, et al.
(författare)
-
Dog ownership and Cardiovascular Risk Factors : a nationwide prospective register-based cohort study
- 2019
-
Ingår i: BMJ Open. - : BMJ. - 2044-6055. ; 9
-
Tidskriftsartikel (refereegranskat)abstract
- Objective To study the association between dog ownership and cardiovascular risk factors.Design A nationwide register–based cohort study and a cross-sectional study in a subset.Setting A cohort of 2 026 865 participants was identified from the Register of the Total Population and linked to national registers for information on dog ownership, prescribed medication, hospital admissions, education level, income and country of birth. Participants were followed from 1 October, 2006, to the end of the study on 31 December, 2012, assessing medication for a cardiovascular risk factor, emigration and death. Cross-sectional associations were further assessed in 10 110 individuals from the TwinGene study with additional adjustment for professional level, employment status, Charlson comorbidity index, disability and tobacco use.Participants All Swedish residents aged 45–80 years on 1 October, 2006.Main outcome measures Initiation of medication for hypertension, dyslipidaemia and diabetes mellitus.Results After adjustment for confounders, the results indicated slightly higher likelihood of initiating antihypertensive (HR, 1.02; 95% CI, 1.01 to 1.03) and lipid-lowering treatment (HR, 1.02; 95% CI, 1.01 to 1.04) in dog owners than in non-owners, particularly among those aged 45–60 years and in those owning mixed breed or companion/toy breed dogs. No association of dog ownership with initiation of treatment for diabetes was found in the overall analysis (HR, 0.98; 95% CI, 0.95 to 1.01). Sensitivity analyses in the TwinGene cohort indicated confounding of the association between dog ownership and prevalent treatment for hypertension, dyslipidaemia and diabetes mellitus, respectively, from factors not available in the national cohort, such as employment status and non cardiovascularchronic disease status.Conclusions In this large cohort study, dog ownership was associated with a minimally higher risk of initiation of treatment for hypertension and dyslipidaemia implying that the previously reported lower risk of cardiovascular mortality among dog owners in this cohort is not explained by reduced hypertension and dyslipidaemia. These observations may suffer from residual confounding despite access to multiple important covariates, and future studies may add valuable information.
|
|
| 10. |
- Stattin, Karl
(författare)
-
Epidemiology of Physical Activity and Fragility Fractures
- 2020
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Fragility fractures mainly affect elderly individuals and often cause long term pain, loss of function and higher mortality rates. Physical activity improves balance, increases muscle strength and bone mineral density, and may reduce the risk of fragility fractures. The aim of this thesis is to investigate the association between physical activity and fragility fractures.In Paper I the risk of hip and any fracture was investigated across levels of habitual walking/bicycling and exercise in participants from the population-based Cohort of Swedish Men (COSM) and Swedish Mammography Cohort (SMC). Individuals walking/bicycling a maximum of 20 minutes per day had a lower risk of hip and any fracture than individuals who did not walk or bicycle. The risk of hip and any fracture was gradually lower with increasing levels of exercise. In Paper II participants in the cross-country skiing race Vasaloppet were compared to non-participants from the general population, and were found to have a higher risk of any and forearm fracture but a lower risk of hip, proximal humerus and lower leg fracture. There was no difference in the risk of vertebral fracture. In Paper III, the association between physical activity and cardiovascular candidate plasma protein concentrations were analyzed in participants from the EpiHealth cohort and the Swedish Mammography Cohort Clinical. Of 184 assayed proteins, 75 associations with physical activity were discovered and 28 subsequently replicated in multivariable adjusted models. In Paper IV the COSM, SMC and the Vasaloppet cohort were combined to achieve as wide a range of physical activity as possible and a common measure of physical activity was created using generalized structural equation modeling (GSEM). Low levels of physical activity were associated with higher risk of any and hip fracture but lower risk of wrist fracture. Individuals with physical activity close to the median of the combined cohort had the lowest risk of fracture, and higher levels of physical activity was associated with a higher risk of any fracture.In conclusion, physical activity is associated with a lower risk of major fractures such as hip fractures, but may in large quantities increase the risk of wrist and any fracture. Physical activity is associated with more beneficial concentrations of 28 cardiovascular plasma proteins.
|
|
