| 1. |
- E:son Jennersjö, Pär, 1956-
(författare)
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Risk factors in type 2 diabetes with emphasis on blood pressure, physical activity and serum vitamin D
- 2016
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- BackgroundType 2 diabetes is a common chronic disease with a two-fold increased risk for cardiovascular morbidity and mortality and has an increasing prevalence worldwide. This thesis is based on a study conducted in primary health care in Östergötland and Jönköping, Sweden. The aim of the thesis was to evaluate new risk markers to identify patients with high risk of developing cardiovascular disease in middle-aged men and women with type 2 diabetes.MethodsData from the cohort study CArdiovascular Risk in type 2 DIabetes – a Prospective study in Primary care (CARDIPP) was used. In paper III data were also used from CARDIPP-Revisited where all participants in the CARDIPP study were invited four years after the baseline investigation for a re-investigation. In paper IV data were used from CAREFUL which is a control group of 185 subjects without diabetes. The investigation included a standard medical history including data on diabetes duration and on-going medication. Anthropometric data were recorded and both office and ambulatory blood pressure were measured. The patients filled out a detailed questionnaire and physical activity was measured by using waist-mounted pedometers. Pedometer-determined physical activity was classified in four groups: Group 1: <5000 steps/day (‘sedentary’); Group 2: 5000-7499 steps/day (‘low active’); Group 3: 7500-9999 steps/day (‘somewhat active’); Group 4: and ≥10 000 steps/day (‘active’). Blood samples were drawn for routine analyses and also frozen for later analyses. The investigations at the departments of physiology included echocardiography, measurements of the carotid intima-media thickness, applanation tonometry and measurements of sagittal abdominal diameter.ResultsPaper 1:Patients with a non-dipping systolic blood pressure pattern showed higher left ventricular mass index and pulse wave velocity (PWV) compared with patients with ≥10% decline in nocturnal systolic blood pressure. Patients with <10% decline in nocturnal systolic blood pressure had higher BMI and sagittal abdominal diameter, lower GFR and higher albumin:creatinine ratio and also higher levels of NT-proBNP than patients with a dipping pattern of the nocturnal blood pressure.Paper 2:The number of steps/day were inversely significantly associated with BMI, waist circumference and sagittal abdominal diameter, levels of CRP, levels of interleukin-6 and PWV.Paper 3:At the 4-year follow-up the change in PWV (ΔPWV) from baseline was calculated. The group with the lowest steps/day had a significantly higher increase in ΔPWV compared with the group with the highest steps/day. The associations between baseline steps/day and ΔPWV remained after further adjustment in a multivariate linear regression statistically significant (p=0.005). 23% of the variation in the study could be explained by our model. Every 1000 extra steps at baseline reduced the change in ΔPWV by 0.103 m/s between baseline and follow-up.Paper 4:Low vitamin D levels were associated with significantly increased risk for premature mortality in men with type 2 diabetes. High levels of parathyroid hormone were associated with significantly increased risk for premature mortality in women with type 2 diabetes. These relationships were still statistically significant also when two other well-established risk markers for mortality, PWV and carotid intima-media thickness, were added to the analyses.ConclusionsAmbulatory blood pressure recording can by addressing the issue of diurnal blood pressure variation, explore early cardiovascular organ damage and microvascular complications that goes beyond effects of standardised office blood pressure measurements. Pedometer-determined physical activity may serve as a surrogate marker for inflammation and subclinical organ damage in patients with type 2 diabetes. There is novel support for the durable vascular protective role of a high level of daily physical activity, which is independent of BMI and systolic blood pressure. The use of pedometers is feasible in clinical practice and provides objective information not only about physical activity but also the future risk for subclinical organ damage in middle-aged people with type 2 diabetes. Our results indicate that low vitamin D levels in men or high parathyroid hormone levels in women give independent prognostic information of an increased risk for total mortality.
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| 2. |
- Ekblom Bak, Elin
(författare)
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Physical activity, cardiorespiratory fitness, and abdominal obesity in relation to cardiovascular disease risk : epidemiological studies
- 2013
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Although Sweden saw a decline in death rates related to cardiovascular disease (CVD) between 1987 and 2011, it is still the most common cause of death for both women and men. Lifestyle-related factors such as inadequate physical activity (PA), poor cardiorespiratory fitness (CF), and excess body fat are all recognised as important predictors of CVD morbidity and mortality. More recently, studies have highlighted the possible detrimental effects of prolonged sitting, which mainly substitutes for daily non-exercise PA (NEPA). Conversely, more preferable levels of these lifestyle factors are associated with lower CVD risk and increased life expectancy. Despite the extensive research performed within this field, there is still no consensus.The main objective of this thesis was therefore to examine the interrelationship between different levels of PA, CF, and abdominal adiposity and their association with CVD risk factors, CVD morbidity, and longevity in population-based samples of Swedish men and women of different ages. A second objective was to develop a new and more precise method for estimation of CF in a mixed, healthy, population.The main findings were- In a cross-sectional population based random sample of Swedish men (n=781) and women (n=890) aged 20 to 65 years were CF and abdominal obesity each independently and strongly beneficially associated with individual CVD risk factors, as well as to a clustered CVD risk factor profile. For the clustered risk, each unit of fitness (ml·kg-1·min-1) was associated with a 5% decrease in risk and each unit of waist circumference (cm) with a 5% increase in risk. This was seen in women as well as men, younger as well as older people, and daily smokers as well as non-smokers; however, there were some differences within the subgroups.- In the same population, higher levels of self-reported PA and CF, but mainly the latter, were independently associated in a beneficial way with both individual and clustered CVD risk factors. Furthermore, a notable interaction of excess clustered CVD risk was shown for being insufficiently physical active according to general guidelines in combination with not being fit.- In a representative cohort of 60-year-old men (n=2039) and women (n=2193) in Stockholm County, a generally active daily life was associated with beneficial metabolic health at baseline and an approximately 30% lower risk for a first-time cardiovascular event and all-cause mortality, respectively, after 12.5 years. These relationships were independent of regular exercise.- A new submaximal cycle ergometer test for estimation of maximal oxygen uptake was developed. The test is simple, low-risk, and easily administered, and does not require laboratory equipment or expertise. In a mixed population (in terms of age, activity status, and gender), the test showed a significantly increased precision compared with one of the most commonly used submaximal exercise tests today.In conclusion, these results indicate that in clinical practice it is important to evaluate both PA and CF as well as abdominal obesity status. Regarding PA, it is important to highlight the separate beneficial associations of a daily active life including NEPA on the one hand, and intentional regular exercise on the other.
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| 3. |
- Johansson, Lisbeth
(författare)
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To do or not to do? Physical activity in relation to socioeconomic status and health – a salutogenic perspective in the context of targeted health dialogues
- 2024
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- It is well known that physical activity (PA) has a major positive impact on health and that the performance of PA is lower in low socioeconomic groups. However, more knowledge about the relationship between PA and health is needed especially between and within socioeconomic groups.This thesis aimed, from a salutogenic perspective, to increase the understanding of the relationship between physical activity and health in the adult population, with a particular focus on people with economic difficulties. A further aim was to validate questions about physical activity and to explore the people’s experiences of PA from a sense of coherence perspective, all in the context of targeted health dialogues.The first study in this thesis is a validation study. It validates a PA interview form and questions about sedentary time used in the targeted health dialogues. Studies II and III comprise quantitative analyses of PA, health and psychological factors in the population, especially in groups with low socioeconomic status (SES). Study IV is a qualitative deductive study based on interviews with participants with low SES in the targeted health dialogues. The deductive analysis contains the participants’ experiences of PA from a sense of coherence perspective.The findings in study I showed that the interview form and the single-item question about sedentary time could be considered as acceptable to use in Swedish targeted health dialogues. In study II, physically active people with low SES were shown to have the same odds of reporting good self-rated health compared to those with low PA and high SES. The findings in study III showed that within the group of people with self-reported economic difficulties, higher levels of PA were related to better mastery and more vitality. Study IV showed that it is essential for the participants to have an awareness of the health benefits of PA and their challenges in performing PA. The participants also constructed a plan to follow while utilising their resources, and their intrinsic motivation to achieve the PA recommendations and the PA benefits.This thesis brings a deeper knowledge and understanding of the healthperspective of PA. This knowledge can be used to further develop thetargeted health dialogues in a salutogenic way. It will give people,especially those with lower SES, the opportunity to use their resourcesto increase PA and thereby improve their future health.
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| 4. |
- Olai, Lena, 1958-
(författare)
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Life After a Stroke Event : With Special Reference to Aspects on Prognosis, Health and Municipality Care Utilization, and Life Satisfaction Among Patients and Their Informal Caregivers
- 2010
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Objectives. The aim of this thesis was to study the prognosis, health care utilization and health situation in stroke patients, and informal caregiver burden during the first post-stroke year. Material and methods. 390 patients, 65 years or older, discharged from hospital after a stroke, were followed with repeated patient interviews, patient record and register data, and hospital staff and informal caregiver questionnaires. Results. Prognosis assessments performed by hospital staff at discharge regarding the course of events during the following year were highly accurate and were mainly influenced by the patient’s pre- and post-morbid state. The risk of dying or having a new stroke decreased rapidly during the early post-morbid phase. Health care utilization, in hospitals as well as in primary health care, and municipal social service support was considerably higher after the stroke than before, but the utilization of services was lower than previously reported. Health problem prevalence according to interview and record scrutiny was modest, peaked early after discharge and then declined. Support from informal caregivers increased significantly after discharge and remained high during the first post-stroke year. The support given was mainly determined by patient functional ability, distance to patient, relation to patient, municipal social service support provided, and patient sex. The informal caregivers reported considerable strain and burden, with significantly higher levels of anxiety and depression than the stroke patients. Moreover, there was a parallel between the patient’s and the caregiver’s situation regarding anxiety, emotional and social situation, and home, social and outdoor activities. Conclusion. Hospital staff prognosis assessments of patient outcomes during the next year were highly accurate. Risk of recurrence and mortality, and health problem prevalence was high in the early post-stroke period, and than declined. Health care utilization and municipality social support increased over time. Informal caregivers reported considerable strain and burden.
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| 5. |
- Rapp [Nordin], Erika, 1970-
(författare)
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Sensory, attitudinal, and contextual aspects of the meal : health implications and connections with risk factors for coronary heart disease and obesity
- 2008
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Det övergripande syftet var att undersöka mat- och måltidsrelaterade faktorer som bidragande orsak till övervikt och hjärt-kärlsjukdom.I en sensorisk studie jämfördes individer som insjuknat i hjärtinfarkt med en frisk kontroll-grupp med avseende på preferens för mat med hög respektive låg fetthalt, smakkänslighet för grundsmakerna (surt, beskt, salt, sött, umami och metalliskt) samt det beska ämnet 6-n-propylthiouracil (PROP). Undersökningsgruppen hade mer ogynnsam metabolisk profil, vilket kan indikera högre intag av fet, energirik mat och mindre intag av frukt och grönsaker, jämfört med kontrollgruppen. Det påvisades emellertid ingen signifikant skillnad i smakkänslighet mel-lan grupperna. När grupperna slogs samman konstaterades däremot att känslighet för surt var relaterat till lågt body mass index (BMI), och känslighet för beska var relaterat till lågt HDL-kolesterol samt högt BMI och bukfetma. Det indikerar ett samband mellan riskprofil, smak-känslighet och matvanor. Upplevd beska kan vara en bidragande orsak till låg konsumtion av frukt och grönsaker. Båda grupperna föredrog generellt mat med hög fetthalt, varför preferens för hög fetthalt i sig inte kan anses vara en bidragande riskfaktor för insjuknande i hjärtinfarkt. För hälften av rätterna påvisades emellertid ingen signifikant skillnad i preferens för hög- respek-tive låg fetthalt. För att undersöka hur sensoriska egenskaper förändras vid olika fetthalter stu-derades två såser med varierande smörmängd. Totalt sett minskade smakegenskaperna (tomat, vitlök, timjan, kyckling, syrlighet) när mer smör tillsattes, medan smörsmaken och såsernas vis-kositet ökade. Stor skillnad i smörmängd (energiinnehåll) frambringar däremot endast små smakförändringar.I en enkätstudie påvisades att matvanor och inställning till mat och hälsa skilde sig mellan män och kvinnor samt beroende av BMI. En klusteranalys resulterade i tre grupper, varav en grupp med jämn könsfördelning som i genomsnitt hade högre BMI och sämre matvanor. I den gruppen ingick kvinnor som är mindre intresserade av sin hälsa och män som är mer fokuserade på mat som njutning, vilket indikerar att orsakerna till ohälsosamma matvanor skiljer sig mellan kvinnor och män. I en öppen fråga beskrevs essensen i en god måltid innefatta både krav på maten (råvaror, maträtter, menyer, sensoriska egenskaper samt näring och mättnad) och krav på sammanhanget (estetik, gemenskap, lugn och ro, och sinnesstämning). Att identifiera indivi-ders olika anspråk på en god måltid kan vara komplementära kunskaper till hjälp vid föränd-ring av mat- och måltidsvanor. Slutligen bidrog en litteraturfördjupning till kunskaper om mat- måltidsupplevelser med fokus på uppskattning och tillfredsställelse i relation till hälsotillstånd.Resultaten indikerar att det är av betydelse att identifiera enskilda individers förutsättningar och preferenser för mat och måltider vad gäller smak, matvanor och kontext i vardagen för att underlätta intervention och hälsofrämjande arbete.
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| 6. |
- Spörndly-Nees, Søren
(författare)
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Physical activity and eating behaviour in sleep disorders
- 2016
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Sleep-disordered breathing and insomnia are common sleep disorders and associated with an increased risk of morbidity. The aim of this thesis was to study the contribution of a behavioural sleep medicine perspective on sleep-disordered breathing and insomnia. More specific, factors considered important for changing eating behaviour and the impact of physical activity were studied.Methods: In study I, semi-structured interviews of participants with obstructive sleep apnoea and obesity (n = 15) were analysed using a qualitative content analysis. A population-based female cohort was followed prospectively over ten years in study II and III using a postal questionnaire on two occasions (n = 4,851 and n = 5062, respectively). In study IV, a series of five experimental single-case studies was conducted testing how an aerobic exercise intervention affected selected typical snores, following an A1B1A2B2A3 design over nine days and nights (n = 5).Results: Facilitators and barriers towards eating behaviour change were identified. A low level of self-reported leisure-time physical activity was a risk factor among women for future habitual snoring complaints, independent of weight, weight gain alcohol dependence or smoking. Maintaining higher levels or increasing levels of leisure-time physical activity over the ten-year period partly protected from snoring complaints (study II). Further, a low level of self-reported leisure-time physical activity is a risk factor for future insomnia among women. Maintaining higher levels or increasing levels of leisure-time physical activity over the ten-year period partly protect against self-reported insomnia, independent of psychological distress, age, change in body mass index, smoking, alcohol dependence, snoring status or level of education (study III). Single bouts of aerobic exercise did not produce an acute effect on snoring the following nights in the studied individuals. A pronounced night-to-night variation in snoring was identified (study IV).Conclusion: Women with sleep disorders would benefit from a behavioural sleep medicine perspective targeting their physical activity in the prevention and management of snoring and insomnia. This is motivated by the protective effects of physical activity confirmed by this thesis.Knowledge was added about facilitators and barriers for future eating behaviour change interventions.
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| 7. |
- Bengtsson, Anna, 1973-
(författare)
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Pictorial presentation of subclinical atherosclerosis : a measure to reduce the risk for cardiovascular disease
- 2021
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The overall aim was improved cardiovascular disease (CVD) prevention through the VIPVIZA intervention. This includes the provision of pictorial information of subclinical atherosclerosis to participants and their general practitioners (GPs), follow-up phone call, and written information to the participant. VIPVIZA is a Prospective Randomized Open Blinded End-point (PROBE) trial nested within VIP, a CVD prevention program in primary health care in Västerbotten county, Sweden. Middle-aged individuals at low/intermediate CVD risk were enrolled to VIPVIZA and randomized 1:1 to an intervention (n=1749) or control group (n=1783 who received no pictorial or other information). Preventive measures were managed within primary health care.At baseline, clinical risk factors were measured and carotid ultrasound examination was performed. The prevalence of subclinical atherosclerotic disease was assessed as intima media thickness and presence of plaque. The association between clinical risk factors and measures of subclinical atherosclerosis was investigated. In addition to conventional risk factor-based risk evaluation, the impact of the VIPVIZA intervention on CVD risk, traditional risk factors and pharmacological treatment was evaluated after 1 and 3 years. Individual interviews were conducted with 15 GPs to explore how a pictorial representation of subclinical atherosclerosis affects physicians in their perception and communication of CVD risk. The interviews were analyzed by qualitative content analysis.The plaque prevalence was 44.7% in this population. Clinical risk factors explained more of the variation in a combined ultrasound measurement than single measurements. The results up to three years showed a VIPVIZA intervention effect, with lower and sustained CVD risk in the intervention as compared to the control group. The effect was partly mediated by differences in intake of lipid-lowering medication and partly by lifestyle behaviour. The GPs described their risk assessment and patients’ risk perception as more accurate with the VIPVIZA intervention. Informing patients about examination results prior to a consultation can facilitate shared decision-making and enhance adherence to preventive measures.The results show that the VIPVIZA intervention reduces CVD risk over three years. In the long run this has the potential to reduce the incidence of CVD events.
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| 8. |
- Gulliksson, Mats, 1954-
(författare)
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Studies of Secondary Prevention after Coronary Heart Disease with Special Reference to Determinants of Recurrent Event Rate
- 2009
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Objectives. The first aim was to examine the effects of secondary prevention with a focus on determinants in the risk of recurrent coronary heart disease (CHD). The second aim was to analyse the effects of a cognitive behavioural therapy (CBT) intervention on the risk of recurrent cardiovascular disease (CVD) and to investigate the psychosocial situation of CHD patients. Material and methods. Papers I and II were based on the Swedish Acute Myocardial Infarction Statistics Register, 1969 to 2001: 775,901 events in 589,341 subjects. Papers III and IV were based on The Secondary Prevention in Uppsala Primary Care project (SUPRIM), a randomized controlled clinical trial in 362 CHD patients. Results. The risk of a recurrent acute myocardial infarction (AMI) event was highly dependent on time from the previous event, with the greatest risk immediately after an AMI event. In addition, sex, age, and AMI number influenced the general risk level. Furthermore, there has been a major decline in recurrence risk over 30 years, and there were considerable geographical differences in risk, best explained by residential area population density, with a high recurrent AMI risk in areas with the lowest and the highest population densities, and the lowest risk in areas with moderate population density. Disease status and sex were determinants of psychological well-being the first year after a CHD event. Sex seemed to be the stronger determinant. The CBT intervention focused on stress management during one year in patients with CHD. There was significantly improved outcome in the intervention group on recurrent CVD and recurrent AMI during a 9 year follow up. A dose-response relationship was demonstrated between attendance rate at intervention group meetings and outcome, the higher the attendance rate the better the outcome. Conclusions. The risk of a recurrent AMI event was dependent on time from the previous event, with major improvement seen in recent decades. Regional differences were best explained by population density. Female CHD patients were at high risk concerning well-being after a coronary event, which deserves special attention. The CBT intervention for CHD patients improved outcomes concerning the risk of recurrent CVD and AMI events.
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| 9. |
- Lindvall, Kristina, 1981-
(författare)
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Being able to be stable : exploring primary weight maintenance as a public health strategy for obesity prevention
- 2013
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Background Overweight and obesity are considerable public health issues internationally as well as in Sweden. On a global level, the obesity prevalence has nearly doubled over the last 30 years. Currently in Sweden, more than one third of all women, and slightly more than half of all men, are either overweight or obese. The long-term results of obesity treatment programs are modest as reported by other studies. The importance of extending the focus to not only obesity treatment, but also prevention of weight gain, has therefore been emphasized.Aim The overall aim of this thesis is to explore the concept of primary weight maintenance (PWM) and to increase the knowledge of the attitudes, behaviours, strategies and surrounding circumstances that are important for PWM in a Swedish middle-aged population.Material and methods All study participants were recruited based on their previous participation in a health survey in their home setting; The Västerbotten Intervention Programme (VIP) in Västerbotten Sweden (paperI-IV), or the Upstate Health and Wellness Study in Upstate New York (IV), USA. All subjects had participated twice, with a time period of ten years between health surveys. The prevalence of obesity between the years 1990-2004 was calculated for VIP participants (paper I). Ten-year non-gain (lost weight or maintained body weight within 3% of baseline weight) or weightgain (≥3%) was calculated for individuals aged 30, 40, or 50 years at baseline. A multivariate logistic regression model was built to predict weight non-gain. In-depth interviews were conducted with 23 maintainers and four slight gainers in Sweden and analysed using Grounded Theory (paper II). A questionnaire study was conducted including 2138 Swedish and 2134 US participants (paper III and IV). Analysis of variance (ANOVA), correlation, and linear regression were performed to identify attitudes, strategies, and behaviours that are predictive of PWM in different age, sex and BMI subgroups in Sweden (paper III). Further, the pattern of ten-year weightchange (% and kg) in 1999-2009 was calculated for Swedish and US women within different subgroups (paper IV). ANOVA, correlation and chi-squaretests were conducted to contrast eating and exercise habits between the two countries that may explain the differences in weight change.Results The prevalence of obesity (BMI ≥30) in Västerbotten increased from 9.4% in 1990 to 17.5% in 2004 (I). Older age, being female, being overweight at baseline, later survey year, baseline diagnosis of diabetes, and lack of snuff use increased the chances of not gaining weight. Based on the in-depth interviews, describing attitudes, behaviours and strategies of importance for PWM, a model was constructed (II). Weight maintenance was characterized as “a tightrope walk” and four strategies of significance for PWM were described as “to rely on heritage”, “to find the joy”, “to find the routine” and “to be in control”. The questionnaire study aimed at identifying predictors of PWM in different age, sex and BMI groups (III). The pattern of significant predictors was widely disparate between different subgroups. Of 166 predictors tested, 152 (91.6%) were predictive of PWM in at least one subgroup. However, only 4.6% of these were significant in half of the subgroups or more. The mean percent weight changes (in all cases weightgain), between 1999-2009 for Swedish and US women, were 4.9% (SD=5.8) and 9.1% (SD=13.7) respectively (p for t-test˂0.001) (IV). For the US women, the largest weight change occurred among the 30 year olds for all three BMI strata. For the Swedish, it was seen among overweight and obese 30 year old women. The largest difference in ten-year weight change between the two countries for any two matched subgroups was seen in normal weight 30 year olds. Significantly more of the women in this Swedish subgroup stated having more of healthy behaviours. However, there was a tendency for unhealthy behaviours to be strongly associated with greater weight gain in the US, but much less so in Sweden.Conclusion: Younger individuals, those of normal body weight, and those without health conditions (e.g. diabetes type 2) and cardiovascular riskfactors – were the least likely to maintain their weight over the 10 year period (I). Educational efforts on the prevention of overweight and obesity should therefore be broadened to include those individuals. The in-depth interview study showed great variety with regard to attitudes, strategies and behaviours important for PWM (II). The results from this study informs health personnel about the need to tailor advice related to body weight, not only to different sub-groups of individuals trying to lose weight but also to subgroups of primary weight maintainers who are trying to maintain weight. This statement was also supported by the questionnaire data, where the large disparity in the pattern of significant variables between subgroups suggests that these interventions should be tailored to the person’s demographic (age,sex and BMI) (III). Paper IV showed that even though the prevalence of obesity among Swedish women has increased substantially during these ten years, it has not kept pace with the increase in the US. One explanation for this may be that normal 30 year old Swedish women have more healthy behaviours than do US women. However, the insensitivity of the Swedish women to weight gain for healthy versus unhealthy alternatives may also be a factor. If the exact reason behind this phenomenon can be identified this may contribute to a deeper understanding of PWM both in Sweden and the US.
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| 10. |
- Norberg, Margareta, 1951-
(författare)
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Identifying risk of type 2 diabetes : epidemiologic perspectives from biomarkers to lifestyle
- 2006
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Type 2 diabetes is a significant health problem because of its high prevalence and strong association with cardiovascular morbidity and mortality. An increase of type 2 diabetes is predicted due to increasing obesity and sedentary lifestyle habits. The development from latent to diagnostic disease spans many years and during this time it is possible to prevent or postpone type 2 diabetes using lifestyle and pharmacological interventions. The objective of this thesis is to investigate and describe early patterns and risk indicators of type 2 diabetes. The focus is on type 2 diabetes as one component in metabolic syndrome, i.e. the clustering of several cardiovascular risk markers. Two studies based on the Västerbotten Intervention Programme (VIP) provided the data; one case-referent study nested within VIP which includes 237 diabetes cases that were clinically diagnosed 5.4 years after the health survey, each with two referents; and one panel study with 5 consecutive annual cohorts including subjects that participated in VIP between1990 and 1994 and returned to a follow-up after 10 years, a total of 16 492 individuals. Associations between risk markers and type 2 diabetes or metabolic syndrome are evaluated by several statistical techniques. A model of metabolic syndrome is hypothesized. A prediction model for developing type 2 diabetes among middle-aged individuals is proposed, where high risk is defined as having at least two out of three risk criteria (fasting plasma glucose ≥6.1 mmol/L, HbA1c ≥4.7% (Swedish Mono-S standard) and BMI ≥27 in men and BMI ≥30 in women). With positive predictive values of 32% in men and 46% in women, this model performs at least as well as other published prediction models. Information on family history of diabetes does not improve the result and the cumbersome oral glucose tolerance test is not needed. Therefore this model should be feasible for use in routine care. A model of metabolic syndrome with five composite factors, based on 14 variables including markers produced by adipose tissue and b-cells, suggest that obesity with insulin resistance and b-cell decompensation are the core perturbations in the early stages of type 2 diabetes, while inflammation and dyslipidemia could not be shown to be independent early risk indicators. The composite factors do not improve the prediction as compared to the single markers of fasting glucose, BMI and proinsulin and, possibly blood pressure values. Stress (measured as passive or tense working conditions) and weak social support (measured as emotional support), are suggested to be strong risk indicators along with high BMI for type 2 diabetes in women. In men BMI is predictive, but the stress variables are not shown to be associated with future type 2 diabetes. A social gap is indicated by double risk of metabolic syndrome among subjects with low (≤ 9 years at school) compared to high education (≥ 13 years). High consumption of Swedish smokeless tobacco, snuff (>4 cans/week), is independently associated with metabolic syndrome, obesity and hypertriglyceridemia, but not with dysregulation of glucose. To conclude, single markers, that are commonly used in daily practice, are useful and sufficient for identification of subjects that are in the early stages of type 2 diabetes. Obesity with insulin resistance and b-cell decompensation are the core perturbations in early development to T2DM. Lifestyle, socioeconomic and psychosocial markers, in addition to biomarkers, are important determinants of future type 2 diabetes and metabolic syndrome, albeit not similarly among men and women.
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