Prevalence of known and previously unknown diabetes mellitus and impaired glucose tolerance in an adult Norwegian population. Indications of an increasing diabetes prevalence. The Nord-Trøndelag Diabetes Study

The worldwide trend in diabetes awareness, treatment, and control from 1985 to 2022: a systematic review and meta-analysis of 233 population-representative studies

Background

With the rapid increase in the prevalence of DM, studies on the awareness, treatment, and control of this condition are essential. Therefore, this study aimed to review the literature and pool the awareness, treatment, and control of diabetes at the global, regional, and national levels.

Methods

In this systematic review and meta-analysis, several databases, including MEDLINE/PubMed, Institute of Scientific Information (ISI), Scopus, and Google Scholar, were searched using appropriate keywords up to June 2022. Observational studies investigating the awareness, treatment, and control of glucose levels among diabetic individuals were included. Awareness, treatment, and control were defined as the proportion of participants who were aware of their diabetes condition, treated pharmacologically, and achieved adequate glucose control, respectively. Two investigators independently conducted the study selection, data extraction, and quality assessment. Heterogeneity among studies was calculated using Chi-square, and a random-effect meta-analysis was used to pool the rates.

Results

A total of 233 studies published between 1985 and 2022 met the inclusion criteria. The included studies had a combined population of 12,537,968. The pooled awareness of DM was 60% (95%CI: 56-63) and ranged from 41% (25-57) in low-income countries to 68% (64-72) in high-income countries, with no significant trend observed over the assessed periods at the global level. The pooled treatment of DM globally was 45% (42-48) and varied from 37% (31-43) in lower-middle-income countries to 53% (47-59) in high-income countries, showing variation over the examined time period. Before 2000, the proportion of adequate DM control was 16% (12-20), which significantly improved and reached 22% (19-25) after 2010. The pooled awareness, treatment, and control of DM were higher in females, high-income countries, and urban areas compared to males, upper and lower-middle-income countries, and rural areas, respectively. The older adults population had higher awareness and treatment rates than the adult population, but their DM control did not differ significantly.

Conclusion

Despite the high level of awareness and treatment among the diabetic population, treatment success (control) is considerably low, particularly in low-income countries and rural areas. It is crucial to improve awareness, treatment, and control by strengthening the primary care system in all countries.

Risk of hip and forearm fracture in subjects with type 2 diabetes mellitus and latent autoimmune diabetes of adults. The HUNT Study, Norway

Type 1 and type 2 diabetes mellitus incur an increased risk of fracture, with a generally higher risk among individuals with type 1 diabetes. The fracture risk among individuals with latent autoimmune diabetes of adulthood (LADA) is not known. The present cohort study aimed to estimate the risk of hip and forearm fracture among individuals with LADA, alongside type 1 and type 2 diabetes, using data from the second survey of the Trøndelag Health Study (HUNT2) in 1995-97. All inhabitants aged 20 years or older (N = 92,936) were invited to attend, of whom 65,234 (70%) participated. A total of 1972 (3%) reported to have diabetes; 1399 were found to have type 2 diabetes, 144 to have LADA, and 138 to have type 1 diabetes. All participants were followed prospectively with respect to hip- and forearm fractures by linkage to the local fracture registry. During a median follow-up of 16.2 years, 2695 persons with hip fractures and 3533 persons with forearm fractures were identified. There was an increased risk of hip fracture in women with type 2 diabetes (HR = 1.51, 95% CI 1.24-1.85) and LADA (HR = 2.15, 95% CI 1.25-3.72), whereas women with type 1 diabetes did not have a significantly increased risk (HR = 2.13, 95% CI 0.89-5.14). Among men, only LADA was associated with an increased risk of hip fracture (HR = 2.69, 95% CI 1.34-5.41). There was no statistically significant association between any of the diabetes types and forearm fracture. In women with type 2 diabetes, the highest risks of hip fracture were observed among those with highest HbA_1c level at baseline, longest time since diagnosis, and most visual and movement impairment. We found that individuals with LADA had an increased risk of hip fracture similar to that previously reported for individuals with type 1 diabetes, and no increased risk of forearm fracture.

Association of risk factors with type 2 diabetes: A systematic review

Diabetes is the leading cause of severe health complications and one of the top 10 causes of death worldwide. To date, diabetes has no cure, and therefore, it is necessary to take precautionary measures to avoid its occurrence. The main aim of this systematic review is to identify the majority of the risk factors for the incidence/prevalence of type 2 diabetes mellitus on one hand, and to give a critical analysis of the cohort/cross-sectional studies which examine the impact of the association of risk factors on diabetes. Consequently, we provide insights on risk factors whose interactions are major players in developing diabetes. We conclude with recommendations to allied health professionals, individuals and government institutions to support better diagnosis and prognosis of the disease.

A randomised controlled study of the long-term effects of exercise training on mortality in elderly people: study protocol for the Generation 100 study

INTRODUCTION

Epidemiological studies suggest that exercise has a tremendous preventative effect on morbidity and premature death, but these findings need to be confirmed by randomised trials. Generation 100 is a randomised, controlled study where the primary aim is to evaluate the effects of 5 years of exercise training on mortality in an elderly population.

METHODS AND ANALYSIS

All men and women born in the years 1936-1942 (n=6966), who were residents of Trondheim, Norway, were invited to participate. Between August 2012 and June 2013, a total of 1567 individuals (790 women) were included and randomised to either 5 years of two weekly sessions of high-intensity training (10 min warm-up followed by 4×4 min intervals at ∼90% of peak heart rate) or, moderate-intensity training (50 min of continuous work at ∼70% of peak heart rate), or to a control group that followed physical activity advice according to national recommendations. Clinical examinations, physical tests and questionnaires will be administered to all participants at baseline, and after 1, 3 and 5 years. Participants will also be followed up by linking to health registries until year 2035.

ETHICS AND DISSEMINATION

The study has been conducted according to the SPIRIT statement. All participants signed a written consent form, and the study has been approved by the Regional Committee for Medical Research Ethics, Norway. Projects such as this are warranted in the literature, and we expect that data from this study will result in numerous papers published in world-leading clinical journals; we will also present the results at international and national conferences.

TRIAL REGISTRATION NUMBER

Clinicaltrials.gov NCT01666340.

The predictive effect of body mass index on type 2 diabetes in the Norwegian women and cancer study

Background

Several studies have analyzed the association of body mass index (BMI) with either the prevalence or incidence of type 2 diabetes (T2D), but no study from Europe or North America has yet analyzed and compared the association of BMI with both incident and prevalent T2D cases.

Methods

Stratified logistic regression was used to calculate odds ratios (OR), and stratified Cox proportional hazards regression was used to calculate hazard ratios (HR) of the effect of BMI on the prevalence, and incidence of T2D. Wald chi-square statistics were applied when comparing the risk estimates.

Results

Among prevalent T2D cases, overweight women (BMI 25–29.9 kg/m²) had an OR of 2.83 (95% confidence interval [CI], 1.92-4.18) and obese women (BMI ≥30 kg/m²) had an OR of 12.12 (95% CI, 8.32-17.68) when compared with normal weight women (BMI <25 kg/m²). Among incident T2D cases, overweight women had a HR of 5.01 (95% CI, 3.59-6.98) and obese women had a HR of 15.99 (95% CI, 11.39-22.46) when compared with normal weight women. After stratification by level of physical activity, and adjustment for age, smoking status, and education level, the Wald chi-square statistic for BMI was 180.90 for prevalent T2D cases, and 262.03 for incident T2D cases.

Conclusion

The predictive effect of BMI was found to be stronger for T2D incidence than T2D prevalence.

HbA₁c versus oral glucose tolerance test as a method to diagnose diabetes mellitus in vascular surgery patients

Background

The diagnosis of diabetes mellitus (DM) is based on either fasting plasma glucose levels or an oral glucose tolerance test (OGTT). Recently, an HbA_1c value of ≥ 48 mmol/mol (6.5%) has been included as an additional test to diagnose DM. The purpose of this study was to validate HbA_1c versus OGTT as a method to diagnose DM in vascular surgery patients.

Methods

The study population consisted of 345 patients admitted consecutively due to peripheral arterial disease. Sixty-seven patients were previously diagnosed with DM. Glucose levels of OGTT and HbA_1c values were analyzed in 275 patients. The OGTT results were categorized into three groups according to the World Health Organization 1999 criteria: 1) DM defined as fasting plasma glucose (FPG) ≥ 7.0 mmol/L and/or two-hour value (2-h-value) ≥ 11.1 mmol/L; 2) intermediate hyperglycaemia, which consists of IGT (FPG < 7.0 mmol/L and a 2-h-value between 7.8 mmol/L and 11.1 mmol/L), and IFG (fasting glucose value between 6.1 mmol/L and 7.0 mmol/L with a normal 2-h-value); and 3) normal glucose metabolism defined as FPG < 6.1 mmol/L and a 2-h-value < 7.8 mmol/L.

Results

Of the 275 patients on whom OGTT was performed, 33 were diagnosed with DM, 90 with intermediate hyperglycaemia and 152 had normal glucose metabolism. An HbA_1c value of ≥ 48 mmol/mol (6.5%) detected DM with a 45.5% sensitivity and a 90% specificity compared with the OGTT results. Combining the measurements of the HbA_1c value with the fasting plasma glucose level (≥7.0 mmol/L) increased the sensitivity to 64%. The total prevalence of DM and intermediate hyperglycaemia was 85% based on HbA_1c values and 45% based on the OGTT.

Conclusions

Compared with the OGTT the HbA_1c cut-off value of ≥ 48 mmol/mol (6.5%) had a 45.5% sensitivity to diagnose DM in patients with peripheral arterial disease. OGTT and HbA_1c categorized different individuals with DM and intermediate hyperglycaemia. The total prevalence of pathologic glucose metabolism was substantially higher based on HbA_1c values than based on OGTT. The high prevalence of DM and intermediate hyperglycaemia when using HbA_1c in this study may reflect a high chronic glycaemic burden in patients with peripheral arterial disease. Further studies on vascular surgery patients are needed to identify which method, OGTT or HbA_1c, is the better in predicting DM and future clinical development of vascular disease.

Trial registration

REK vest 14109

Smoking is associated with reduced risk of autoimmune diabetes in adults contrasting with increased risk in overweight men with type 2 diabetes: a 22-year follow-up of the HUNT study

OBJECTIVE

To investigate the association between smoking habits and risk of autoimmune diabetes in adults and of type 2 diabetes.

RESEARCH DESIGN AND METHODS

We used data from the three surveys of the Nord-Trøndelag Health Study, spanning 1984-2008 and including a cohort of 90,819 Norwegian men (48%) and women (52%) aged ≥20 years. Incident cases of diabetes were identified by questionnaire and classified as type 2 diabetes (n = 1,860) and autoimmune diabetes (n = 140) based on antibodies to glutamic decarboxylase (GADA) and age at onset of diabetes. Hazard ratios (HRs) adjusted for confounders were estimated by Cox proportional hazards regression models.

RESULTS

The risk of autoimmune diabetes was reduced by 48% (HR 0.52 [95% CI 0.30-0.89]) in current smokers and 58% in heavy smokers (0.42 [0.18-0.98]). The reduced risk was positively associated with number of pack-years. Heavy smoking was associated with lower levels of GADA (P = 0.001) and higher levels of C-peptide (964 vs. 886 pmol/L; P = 0.03). In contrast, smoking was associated with an increased risk of type 2 diabetes, restricted to overweight men (1.33 [1.10-1.61]). Attributable proportion due to an interaction between overweight and heavy smoking was estimated to 0.40 (95% CI 0.23-0.57).

CONCLUSIONS

In this epidemiological study, smoking is associated with a reduced risk of autoimmune diabetes, possibly linked to an inhibitory effect on the autoimmune process. An increased risk of type 2 diabetes was restricted to overweight men.

Alcohol consumption is associated with reduced risk of Type 2 diabetes and autoimmune diabetes in adults: results from the Nord-Trøndelag health study

AIMS

We investigated the influence of different aspects of alcohol consumption on the risk of Type 2 diabetes and autoimmune diabetes in adults.

METHODS

We used data from the Nord-Trøndelag Health Survey (HUNT) study, in which all adults aged ≥ 20 years from Nord-Trondelag County were invited to participate in three surveys in 1984-1986, 1995-1997 and 2006-2008. Patients with diabetes were identified using self-reports, and participants with onset age ≥ 35 years were classified as having Type 2 diabetes if they were negative for anti-glutamic acid decarboxylase (n = 1841) and as having autoimmune diabetes if they were positive for anti-glutamic acid decarboxylase (n = 140). Hazard ratios of amount and frequency of alcohol use, alcoholic beverage choice, and binge drinking and alcohol use disorders were estimated.

RESULTS

Moderate alcohol consumption (adjusted for confounders) was associated with a reduced risk of Type 2 diabetes in men, but not in women (hazard ratio for men 10-15 g/day 0.48, 95% CI 0.28-0.77; hazard ratio for women ≥ 10 g/day 0.81, 95% CI 0.33-1.96). The reduced risk was primarily linked to consumption of wine [hazard ratio 0.93, 95% CI 0.87-0.99 (per g/day)]. No increased risk was seen in participants reporting binge drinking or in problem drinkers. The results were also compatible with a reduced risk of autoimmune diabetes associated with alcohol consumption [hazard ratio 0.70, 95% CI 0.45-1.08 (frequent consumption) and hazard ratio 0.36, 95% CI 0.13-0.97 (2-7 g/day)].

CONCLUSIONS

Moderate alcohol consumption associates with reduced risk of both Type 2 diabetes and autoimmune diabetes. A protective effect of alcohol intake may be limited to men. High alcohol consumption does not seem to carry an increased risk of diabetes.

Creation of a new prospective research biobank: the example of HUNT3

When establishing a biobank, there are a number of issues to consider with significant impact on the outcome of your efforts and the quality of your work. Some of the most relevant are: (1) study design, (2) the size and composition of your cohort, (3) the nature and desired quality of the biological material, and (4) how to handle, store, and retrieve your samples to maintain the best quality for future analyses. In this chapter, we in particular describe the organisation of biobanks derived from population-based prospective health surveys illustrated by the Norwegian HUNT study as a basis for more general considerations.

High levels of education are associated with an increased risk of latent autoimmune diabetes in adults: results from the Nord-Trøndelag health study

OBJECTIVE

To investigate whether the risk for autoimmune diabetes in adults differs between socioeconomic groups and to compare such risk with that for type 2 diabetes.

RESEARCH DESIGN AND METHODS

The inhabitants of the Norwegian county of Nord-Trøndelag were investigated by questionnaires and clinical examinations on three occasions during 1984-2008. We used information from a subset consisting of 56,296 subjects (participating in at least two surveys), including 122 incident cases of autoimmune diabetes in adults (aged ≥35 and anti-GAD positive) and 1,555 cases of type 2 diabetes (aged ≥35 and anti-GAD negative). Hazard ratios (HRs) of diabetes associated with self-reported education and occupation were estimated by Cox proportional hazards models.

RESULTS

High levels of education (university versus primary school) were associated with an increased risk of autoimmune diabetes (HR 1.98 [95% CI 1.21-3.26]), after adjustment for BMI, lifestyle factors, and family history of diabetes. Case subjects with high levels of education had lower levels of C-peptide, tended to have higher levels of anti-GAD, and were more often treated with insulin. Conversely, these subjects had a reduced risk of type 2 diabetes (HR 0.69 [95% CI 0.57-0.82]), a risk that was partly explained by lower BMI and more physical activity (adjusted HR 0.89 [95% CI 0.74-1.06]).

CONCLUSIONS

High levels of education are associated with an increased risk of autoimmune diabetes in adults, a finding that may be mediated by effects on autoimmune activity. Because the association is not explained by traditional risk factors, other, currently unidentified, environmental factors are likely to be involved.

Diabetes mellitus and outcomes of colorectal cancer

BACKGROUND

Patients with diabetes mellitus have an increased risk of colorectal cancer. However, there is limited information on the outcome for diabetic patients diagnosed with this type of cancer.

METHODS

The health records of all 1 194 patients treated for colorectal adenocarcinoma at Levanger Hospital from 1980-2004 were reviewed. Diabetes status and prognostic factors were registered. Primary endpoints were cancer specific survival and overall survival.

RESULTS

There were no significant differences between diabetic patients and non-diabetic patients concerning stage, grade, treatment, infective or non-infective postoperative complications, hospital stay, or 30 days mortality after laparotomy. After a curative resection, the estimated 5-year cancer specific survival in 97 diabetic patients was 73% (95% CI 60-87) and 79% (95% CI 75-82) in 1097 non-diabetic patients (not significant). The estimated overall 5-year survival in patients treated with curative intent was 46% (95% CI 33-59) in diabetic patients and 65% (95% CI 62-69) in non-diabetic patients (p<0.001). The diabetic patients were significantly older and more frequently had cardiac diseases.

CONCLUSION

Diabetes mellitus did not affect the short-term survival or the cancer specific survival. A shorter overall survival was associated with cardiac diseases and higher age.

Incidence of type 1 and type 2 diabetes in adults and children in Kronoberg, Sweden

All newly diagnosed diabetes in Kronoberg during 3 years was registered, with blood samples from 1630/1666 (97.8%) adults. Those positive for GADab and/or ICA and/or C-peptide<0.25nmol/L (0.7%) were classified as type 1 diabetes, the remaining as type 2. Incidence of type 1 in 0-19-year-olds was 37.8(36.1-39.6, 95%CI) and in 20-100 year-olds 27.1(25.6-27.4) per 100 000 and year, it was bimodal with equal peaks in 0-9 year-olds and in 50-80-year-olds. Adults had type 2 incidence 378 (375-380), children 3.1 (2.6-3.6). Among adults 6.9% had type 1 and 93.1% type 2. Among antibodypositive adults (n=101), GADab were present in 90%, ICA in 71%, both GADab and ICA in 61%. Ophthalmology contact as second source was confirmed for 98%. There were no gender differences in type 1 in any age group, small ones in pediatric subgroups. In type 2 men predominated in ages above 40 years. Incidences of type 1 diabetes in both children and adults were very high and as high above age 50 years as in children. Incidence of type 2 was the highest reported from Sweden, to which new diagnostic criteria, a high degree of case-finding, and many elders, may have contributed, but results may also reflect a true increase in incidence of both types of diabetes.

Influence of family history of diabetes on incidence and prevalence of latent autoimmune diabetes of the adult: results from the Nord-Trøndelag Health Study

OBJECTIVE

The aim of this study was to investigate the association between family history of diabetes (FHD) and prevalence and incidence of latent autoimmune diabetes of the adult (LADA), type 1 diabetes, and type 2 diabetes.

RESEARCH DESIGN AND METHODS

The results were based on cross-sectional data from 64,498 men and women (aged >or=20 years) who were in the Nord-Trøndelag Health Study, which included 128 cases of LADA, 1,134 cases of type 2 diabetes, and 123 cases of type 1 diabetes. In addition, prospective data on 46,210 subjects, which included 80 incident cases of LADA, observed between 1984 and 1986 and 1995 and 1997 were available. Patients with LADA had antibodies against GAD and were insulin independent at diagnosis.

RESULTS

FHD was associated with a four times (odds ratio [OR] 3.92 [95% CI 2.76-5.58]) increased prevalence of LADA. Corresponding estimates for type 2 and type 1 diabetes were 4.2 (3.72-4.75) and 2.78 (1.89-4.10), respectively. Patients with LADA who had FHD had lower levels of C-peptide (541 vs. 715 pmol/l) and were more often treated with insulin (47 vs. 31%) than patients without FHD. Prospective data indicated that subjects with siblings who had diabetes had a 2.5 (1.39-4.51) times increased risk of developing LADA during the 11-year follow-up compared with those without.

CONCLUSIONS

This study indicates that FHD is a strong risk factor for LADA and that the influence of family history may be mediated through a heritable reduction of insulin secretion.

Under-diagnosis of common chronic diseases: prevalence and impact on human health

AIMS

The disability-adjusted life years (DALY) and its components, namely the years lived with disability and the years of life lost, are measures of the impact of disease on human health. Our impression was that several common chronic diseases responsible for many DALYs are frequently under-diagnosed.

METHODS

We attempted to summarise data regarding the under-diagnosis of common chronic diseases of the developed world, which are associated with considerable mortality and/or disability. We searched PubMed and Current Contents to identify relevant studies (1980-2005). Two reviewers extracted data concerning DALYs and prevalence of under-diagnosis of common chronic diseases.

RESULTS

Studies regarding the first 15 diseases (or group of diseases) based on DALYs were reviewed. The under-diagnosis of common chronic diseases in the developed world ranges from about 20% for dementia and cirrhosis to 90% for depression and osteoarthritis. The delay in the prompt diagnosis and initiation of treatment is associated with increased morbidity and mortality for most of the reviewed diseases.

CONCLUSION

The available evidence suggests that the prevalence of under-diagnosis of common chronic diseases is considerable. Physicians should be aware of the prevalence of under-diagnosis of chronic diseases and its impact on human health.

Diabetes in treated hypertension is common and carries a high cardiovascular risk: results from a 28-year follow-up

OBJECTIVE

The objective of this study was to analyse predictive factors for development of type 2 diabetes during life-long therapy for hypertension and the alleged additional cardiovascular risk this constitutes.

METHODS

The study group (n = 754) comprised the hypertensive subgroup of a randomized population sample of 7500 men, aged 47-54 years, screened for cardiovascular risk factors and followed for 25-28 years. The patients were treated with thiazide diuretics and beta-adrenergic blocking drugs with the addition of hydralazin during the first decade. Calcium antagonists were substituted for hydralazin and, if needed, angiotensin-converting enzyme inhibitors were added when these drugs became available.

RESULTS

A total of 148 (20.4%) treated hypertensive patients developed diabetes during 25 years, and in multivariate Cox regression analysis body mass index, serum triglycerides and treatment with beta-blockers were positively related with this complication. New-onset diabetes implied a significantly increased risk for stroke [hazard ratio (HR): 1.67; 95% confidence interval (95% CI): 1.1-2.6; P < 0.05], myocardial infarction (OR: 1.66; 95% CI: 1.1-2.5; P < 0.05) and mortality (OR: 1.42; 95% CI: 1.1-1.9; P < 0.05). The greatest risk for stroke was new-onset diabetes, followed by smoking (OR: 1.46; 95% CI: 1-2.2; P = 0.07) and the greatest risk for myocardial infarction was new-onset diabetes, followed by smoking (HR: 1.64; 95% CI: 1.1-2.4; P < 0.01). The greatest risk for mortality was smoking (HR: 1.73; 95% CI: 1.3-2.2; P < 0.005). Achieved systolic and diastolic blood pressure were not predictive of cardiovascular complications or death. The mean observation time from onset of diabetes mellitus to a first stroke was 9.1 years and to a first myocardial infarction 9.3 years.

CONCLUSION

Diabetes in treated hypertensive patients is alarmingly common and carries a high risk for cardiovascular complications and mortality.

Age, overweight and physical inactivity increase the risk of latent autoimmune diabetes in adults: results from the Nord-Trøndelag health study

AIMS/HYPOTHESIS

Latent autoimmune diabetes (LADA) is a common form of diabetes, yet the risk factors are poorly characterised. The aim of this study was to investigate the influence of age, overweight and physical activity on the risk of LADA.

METHODS

We analysed age, overweight and physical inactivity and the incidence of LADA in 38,800 men and women, observed between 1984 and 1986 and 1995 and 1997 as part of the Nord-Trøndelag Health Survey. We also compared such factors with incident cases of type 2 (n = 738) and 'classic' type 1 diabetes (n = 18). Patients classified as LADA (n = 81) had antibodies against GAD and were insulin independent at diagnosis.

RESULTS

The proportion of those who were older, overweight and inactive before diagnosis was almost identical in LADA and type 2 diabetes patients. BMI >or=30 kg/m(2) was strongly associated with LADA incidence (relative risk [RR] = 15.0, 95% CI 7.51-29.97). The association was similar for type 2 diabetes (RR = 15.37, 95% CI 12.07-19.57) but not for type 1 diabetes. Similarly, age (>or=60 years) was an important risk factor for LADA (RR = 5.62, 95% CI 2.36-13.4) as well as for type 2 diabetes (RR = 6.78, 95% CI 5.07-9.06) in contrast to type 1 diabetes. Physical inactivity was associated with an increased risk of both LADA and type 2 diabetes.

CONCLUSIONS/INTERPRETATION

This study suggests that increased age, overweight and physical inactivity are as strong risk factors for LADA as for type 2 diabetes. These findings suggest a role for insulin resistance in the pathogenesis of LADA.

Subjective well-being before and after the onset of diabetes mellitus: results of the Nord-Trøndelag Health Study

Previous research has documented that people with diabetes mellitus report lower psychological well-being than do people with no reported disease. Very little empirical evidence is available to support the conclusion that the low well-being is a consequence of diabetes per se. In this article, we analysed changes in psychological well-being among people who developed diabetes between 1984-1986 and 1995-1997. On these two occasions, the entire adult population of one county in Norway was invited to health screenings (the Nord-Trøndelag Health Studies, HUNT 1 and HUNT 2). The participants were 77,224 (90.7%) in HUNT 1 and 65,599 (71.0%) in HUNT 2. A total of 46,320 people participated in both studies and were included in the analyses. The participation rate at HUNT 2 was lower among people with diabetes at HUNT 2 than among people without diabetes. The participants responded to questionnaires, including questions on several diseases, as well as self-assessed health and psychological well-being. In this article, the question is raised whether people who developed diabetes in the period between HUNT 1 and HUNT 2 reported lower well-being than people who did not. The analyses show that they did, but the differences were small, except for reported subjective health and vigor. Moreover, we found that people who reported diabetes in HUNT 2 but not in HUNT 1 reported lower well-being and more comorbidity, already in HUNT 1. They also reported a slight decline in well-being in the period, that is, poorer subjectively judged health and life satisfaction, less vigor and cheerfulness, and more use of tranquilizers than before they received the diabetes diagnosis.

Smoking is associated with an increased risk of type 2 diabetes but a decreased risk of autoimmune diabetes in adults: an 11-year follow-up of incidence of diabetes in the Nord-Trøndelag study

AIMS/HYPOTHESIS

We compared the association between smoking habits and later occurrence of type 2 diabetes on the one hand and between smoking and diabetes with autoimmunity on the other hand.

METHODS

We used data from a prospective study of 11-year cumulative incidence of diabetes in the Nord-Trøndelag Health Survey.

RESULTS

Confirming previous reports, heavy smoking (>/=20 cigarettes per day) carried an increased relative risk (RR) of type 2 diabetes (n=738, RR=1.64, 95% CI: 1.12-2.39). In contrast, smoking reduced the risk of latent autoimmune diabetes in adults (LADA) and of traditional type 1 diabetes (LADA n= 81, RR=0.25, 95% CI: 0.11-0.60; type 1 diabetes, n=18, RR=0.17, 95% CI: 0.04-0.73).

CONCLUSIONS/INTERPRETATIONS

The results indicate that nicotine influences autoimmune processes in human diabetes.

Omega-3 fatty acid supply from milk associates with lower type 2 diabetes in men and coronary heart disease in women

BACKGROUND

Omega-3 fatty acids may prevent type 2 diabetes and coronary heart disease (CHD). We investigated these fatty acids in Nordic cow's milk and whether their supply from milk associates with type 2 diabetes prevalence and CHD mortality in the Nordic countries.

METHODS

Samples (N = 84) of consumers' milk were collected in five Nordic countries four times during 1 year. Fatty acids were analyzed using gas chromatography. Fatty acids supply from milk fat was calculated using national food balance sheets.

RESULTS

The omega-3 fatty acids content was higher and omega-6 fatty acid content was lower in Icelandic milk when compared with milk from other Nordic countries. Type 2 diabetes prevalence in men correlated inversely with the supply of omega-3 fatty acids and eicosapentaenic acid, but positively with omega-6/omega-3 ratio in milk. CHD mortality in women correlated inversely with the supply of eicosapentaenic acid but positively with the omega-6/omega-3 ratio.

CONCLUSIONS

Milk fatty acids content can depend upon the origin of the milk. The higher supply of omega-3 fatty acids from milk might explain the lower type 2 diabetes prevalence and CHD mortality in Iceland compared to the other Nordic countries.

Cardiovascular risk factors, change in risk factors over 7 years, and the risk of clinical diabetes mellitus type 2. The Tromsø study

In a large longitudinal study, we examined the relationships between cardiovascular risk factors (blood lipids, blood pressure, smoking, and physical activity), and change in these risk factors over a 7-year period, and the risk of clinical diabetes mellitus type 2. There were 73 verified new cases of clinical diabetes mellitus type 2 (diagnosed between 1987 and 1995) and 9,982 controls who consistently denied diabetes in three health surveys in 1979/1980, 1986/1987, and 1994/1995. Baseline body mass index, serum triglycerides, high-density lipoprotein (HDL) cholesterol, blood pressure, and physical activity in leisure, as well as change in these risk factors, were significant predictors for clinical diabetes mellitus type 2. Thus, both the level of risk factors at baseline and change in risk factor level are of importance for the risk of clinical diabetes mellitus type 2.

Cardiovascular disease and risk factors in persons with type 2 diabetes diagnosed in a large population screening: the Nord-Trøndelag Diabetes Study, Norway

OBJECTIVE

To study cardiovascular status and risk factors in persons with newly diagnosed type 2 diabetes and controls in a large population.

DESIGN

Case-control study.

SETTING

Population screening.

SUBJECTS

The screening of 74 499 individuals (88.1%), aged 20 years and older, in Nord-Trøndelag County, Norway, during 1984-86 detected 428 persons with undiagnosed diabetes according to the 1980 WHO criteria, of whom 205 attended a clinical follow-up examination assessing cardiovascular status and risk factors.

METHODS

For each of 205 cases, one control person matched by age and sex underwent the same clinical examination. Lipids, body mass index, waist/hip ratio, blood pressure, pulse rate, blood pressure medication, kidney function, cardiovascular disease, family history and lifestyle were recorded.

RESULTS

At the screening prior to the diagnosis of diabetes, those with diabetes reported poorer general health, less physical activity, more siblings with diabetes and more frequent use of antihypertensive medication. They had higher body mass index, systolic and diastolic blood pressure and pulse rate compared with controls. At the clinical evaluation, diabetics had higher urine albumin levels, increased waist/hip ratio, and higher total cholesterol/HDL cholesterol ratios than the controls. They also reported a greater incidence of angina pectoris and had more ECG changes.

CONCLUSIONS

Diabetics presented with more cardiovascular risk factors, angina pectoris and ECG changes than the controls, and they had an established metabolic syndrome more often than controls. These results suggest that prevention of cardiovascular disease in diabetics requires earlier diagnosis of the diabetes.

Treatment of diabetes mellitus--physicians' adherence to clinical guidelines in Norway

OBJECTIVE

To assess general practitioners' current adherence to the Norwegian clinical guidelines for the treatment of diabetes mellitus.

DESIGN

Descriptive, retrospective registration of information from patient records of one year; 7 November 1993 to 7 November 1994. In addition, mailed questionnaire to examine the representativeness of the participating doctors.

SETTING

General practice in Sør- and Nord-Trøndelag counties in Norway, 380,000 inhabitants.

PARTICIPANTS

In one year 1119 patients were registered with the diagnosis of diabetes mellitus in the records of 56 general practitioners. The patients were 53% women and 47% men; 51% were 70 years or older.

MAIN OUTCOME MEASURES

Levels of HbA1c and blood pressure in accordance with the recommendations of the Norwegian clinical guidelines for diabetes mellitus. Fractions of patients with a measured HbA1c, blood pressure, and serum cholesterol in one year.

RESULTS

At least one HbA1c was recorded in 77% of the diabetic patients during the specified year. In patients under 70 years of age, 56% had HbA1c above the recommended treatment level of 7.5%. In patients 70 years of age or older, 36% were above the recommended limit of 8.5%. At least one blood pressure was recorded in 79% of the patients during the specified year. In patients under 70 years of age, 53% had a systolic blood pressure above the recommendations of 140 mmHg, and 22% had a diastolic blood pressure above the recommendations of 90 mmHg. Serum cholesterol was not recorded during the specified year in 75% of the patients.

CONCLUSION

There are still major discrepancies between current practice and the intentions laid down in the Norwegian clinical guidelines. A discussion of alternative methods for implementation and evaluation of the efficacy of clinical guidelines is needed.