Etiological aspects of insulin-dependent diabetes mellitus: an epidemiological perspective

Relation between glycemic levels and low tract urinary symptoms in elderly

INTRODUCTION

Due the low mortality attributed to BPH, the evaluation of the impacts of LUTS on quality of life of the patients has great importance, especially on the concern of therapeutic choices, except on cases of formal surgery indication. This increase is directly related with difficulties to perform ordinary tasks and a normal living in community.

OBJECTIVES

Determinate an association among Diabetes mellitus II and BPH symptoms in a group of elder men.

METHODOLOGY

This is an observational clinic trial, comparative. About 62 male subjects, 60 years old or more have been active interviewed. They were divided in two similarly groups. First was composed by men without diabetes and the second with diabetic men. For the evaluation of prostatic symptoms, it was utilized the IPSS.

RESULTS

Mean age on Group I was 67.6 years old, while on Group II was 68.7 years old (p = 0.1521). After questionnaire, 51.5% of participants on Group I and 54.2% on Group II presented Systemic Arterial Hypertension (p = 0.099). IPSS was higher on group II (p < 0.0005).

DISCUSSION

Diabetes mellitus was positively associated with the increasing of the LUTS, especially NOCTÚRIA. Patients on group I had a media of 14.2 points on IPSS questionnaire, while those on group II reached the media of 7 points. This pattern was the same even after the age, corporal mass and social/economic adjustment.

CONCLUSION

There is a statistically association between DM and LUTS on Elder men, evaluated through a specific questionnaire.

Impact of socioeconomic status and gender on glycaemic control, cardiovascular risk factors and diabetes complications in type 1 and 2 diabetes: a population based analysis from a Scottish region

AIMS

In this cross-sectional study, the aims were to investigate the association of the socioeconomic status and gender on the prevalence of type 1 and 2 diabetes, glycaemic control, cardiovascular risk factors plus the complications of diabetes in a population-based analysis in the county of Ayrshire and Arran, Scotland.

METHODS

Quality Outcome Framework data was obtained from General Practices in Ayrshire and Arran, Scotland (n=15,351 patients).

RESULTS

In type 1 diabetes, there was an increasing linear trend in HbA1c across deprivation levels (P<0.01). In type 1 diabetes, obesity in women (P<0.01) and increased non-fasting triglyceride levels in both men and women were associated with deprivation (P<0.05). In type 2 diabetes, there was a significant prevalence trend with deprivation for women (P<0.01) but not with glycaemic control (P=0.12). Smoking, ischaemic heart disease and neuropathy (P<0.01) were all associated with increasing deprivation with gender differences. In type 2 diabetes, reduced HDL cholesterol (P<0.01 both genders), and percentage of people on lipid lowering therapy (men P<0.05; women P<0.01) were associated with deprivation. Smoking, ischaemic heart disease, peripheral vascular disease and neuropathy plus foot ulcers (P<0.05) were all associated with increasing deprivation with gender differences.

CONCLUSIONS

Socioeconomic status and gender are associated with changes in glycaemic control and cardiovascular risk factors plus complication development in both type 1 and 2 diabetes. The mechanisms are unclear but follow-up of these patients should allow greater understanding.

A low incidence of Type 1 diabetes between 1977 and 2001 in south-eastern Sweden in areas with high population density and which are more deprived

AIMS

To explore how socioeconomic factors and population density may contribute to the geographical variation of incidence of Type 1 diabetes in children in south-eastern Sweden.

METHOD

All children diagnosed with Type 1 diabetes in south-eastern Sweden during 1977-2001 were defined geographically to their place of residence and were allocated x and y coordinates in the national grid. The population at risk and socioeconomic data were aggregated in 82,000 200-m squares and geocoded likewise. A socioeconomic index was calculated using a signed chi(2) method. Rural-urban gradients were defined by overlay analysis in a geographic information system.

RESULTS

The incidence during the past 25 years has been rising steadily, particularly in the last 6 years. The incidence was highest in areas with a high proportion of small families, of families with a high family income and better education, and this was found both at the time of diagnosis and at the time of birth. In the rural-urban analysis, the lowest incidence was found in the urban area with > 20,000 inhabitants, where there was also a higher frequency of deprivation.

CONCLUSIONS

Our findings indicate that geographical variations in incidence rates of Type 1 diabetes in children are associated with socioeconomic factors and population density, although other contributing factors remain to be explained.

Hospitalization because of diabetes and bereavement: a national cohort study of parents who lost a child

AIMS

To examine whether parents who lost a child have an increased risk of hospitalization because of Type 1 or Type 2 diabetes.

METHODS

We identified all parents who lost a child in Denmark from 1980 to 1996 (stress exposed), and compared them with parents randomly selected from all other parents in the country at that time without such a bereavement. Fifteen non-bereaved families were matched to each bereaved family for family size and the age of the children. First hospitalizations for Type 1 or Type 2 diabetes were monitored in these two groups up to 18 years after the bereavement. There were 21 062 parents in the bereaved cohort and 293 745 parents in the non-bereaved cohort. The study was based upon linkage of several national registers, and first-time hospitalization with diabetes (Type 1 or Type 2) was the end point.

RESULTS

Five hundred and fifty-one cases were hospitalized because of Type 1 diabetes and 1569 cases because of Type 2 diabetes. There was a 29% higher risk of hospitalization because of Type 1 diabetes [95% CI -5 to 75%; corresponding to a relative risk (RR) of 1.29; 95% CI 0.95-1.75] and a 44% higher risk of hospitalization because of Type 2 diabetes (95% CI 21-71%; corresponding to an RR of 1.44; 95% CI 1.21-1.71) in the bereaved cohort. The high risk of hospitalization because of Type 2 diabetes following bereavement was only statistically significant for mothers.

CONCLUSIONS

Psychological stress may be a contributing cause of, or have prognostic importance for, both Type 1 and Type 2 diabetes, but a statistically significant association was only seen for Type 2 diabetes.

Epidemiology of type 1 and type 2 diabetes. The added value of diabetes registries for conducting clinical studies: the Belgian paradigm

Diabetes registries have documented that the lifetime risk of diabetes amounts to at least 10% in the western world. Moreover the prevalence of type 2 diabetes is increasing worldwide especially in developing countries. Furthermore there is a secular trend toward earlier clinical manifestation of both type 1 and type 2 diabetes. In the absence of a permanent cure for primary diabetes the present estimated number of at least 150 million diabetic patients worldwide is expected to double within the next 20 years. Consequently a sharp increase in the global burden of chronic diabetes complications is to be feared in the coming decades. Therefore it is absolutely mandatory to intensify research efforts aiming at identifying the etiological factors involved and designing effective strategies for prediction and prevention of the disease and its devastating complications. Diabetes registries constitute instruments of choice to conduct such studies because they are able to collect standardised clinical, demographic and biological information from sufficiently large representative groups of patients and risk groups such as first degree relatives. Since 1989, the Belgian Diabetes Registry is studying all types of diabetes presenting before age 40 in Belgium and provides a paradigm of how diabetes registries may also contribute to the advancement of knowledge on disease heterogeneity, etiology, prediction and prevention.

[Characteristics and habits of parents of children with insulin-dependent diabetes mellitus]

The aim of this case-control study conducted in Belgrade during 1994-1997 was to investigate whether parental demographic characteristics and habits are associated with insulin-dependent diabetes mellitus (IDDM). Case group comprised 105 children up to 16 years old with IDDM and control group comprised 210 children with skin diseases. Cases and controls were individually matched by age (+/- one year), sex and place of residence (Belgrade). According to chi 2 test results, children with IDDM significantly had five or more family members and they also significantly more frequently had poor socio-economic status than their controls. Higher education of fathers was significantly more frequently reported in diabetic children, in comparison with their controls. Parents of diabetic children were significantly more frequently occupationally exposed to radiation, petroleum, and its derivates, organic solvents, dyes and lacquers. During pregnancy mothers of diabetic children significantly more frequently smoked cigarettes and consumed coffee, coca-cola, alcohol and foods containing nitrosamines. Fathers of diabetic children more frequently consumed alcohol.

The incidence of type 1 diabetes in the age group 0-39 years has not increased in Antwerp (Belgium) between 1989 and 2000: evidence for earlier disease manifestation

OBJECTIVE

A worldwide increase in the incidence of childhood type 1 diabetes has been observed. Because in various countries the majority of new type 1 diabetic patients are diagnosed in adulthood, we investigated whether the rising incidence of this disorder in children reflects a global increase in the incidence of diabetes or a shift toward earlier clinical presentation.

RESEARCH DESIGN AND METHODS

The incidence of type 1 diabetes presenting before age 40 years was prospectively measured in the Antwerp district over a 12-year period (1989-2000). The completeness of ascertainment was evaluated by the capture-recapture method. Trends in incidence during the study period were analyzed by Poisson regression.

RESULTS

The incidence of type 1 diabetes diagnosed before age 40 years remained constant over the 12-year period, averaging 9.9 cases per 100,000 individuals per year. The incidence was similar in both sexes under age 15 years, but a marked male excess was noted for adult-onset disease, in particular after age 20 years, resulting in a male-to-female ratio of 0.9 under age 15 years vs. 1.6 thereafter (P = 0.001). During the 12-year observation period, there was a significant tendency toward increasing incidence under age 15 years at the expense of a decreasing incidence between ages 15 and 40 years (P = 0.025). The annual increase in incidence averaged 1.8% under age 15 years and 5.0% under age 5 years (P = 0.06).

CONCLUSIONS

Our results indicate that in Belgium, the increasing incidence of childhood type 1 diabetes-especially for children under age 5 years-is not attributable to a global increase in disease incidence, but rather to earlier clinical manifestation. The results suggest that an environmental factor may preferentially accelerate the subclinical disease process in young diabetes-prone subjects.

Potentials and pitfalls in neonatal screening for type 1 diabetes

Childhood-onset diabetes is increasing all over the western world. Only 20-30% of monozygotic twin pairs are concordant for the disease. So far, more than 20 different risk genes have been identified on different chromosomes. The dominating risk genes differ with different age at onset and also in different populations. Thus, the aetiology of the disease is complex, with interactions between different risk genes and environmental risk factors. Several pathogenetic models have been proposed, most of which include autoimmune destruction mechanisms. Screening for genetic markers for diseases with such complex aetiology encounters pitfalls due to the low predictive value of each single marker in the general population. To overcome such problems combinations of markers and decision-tree analysis are necessary. The identification of several immune markers for the disease has provided potential for screening for secondary prevention. When increasing the number of markers to increase the predictive value, sensitivity will be lost. A Swedish population-based study found the best combined positive predictive value in the general population to be 20%, whereas the sensitivity was only 34%. Type 1 diabetes still needs more precise risk markers in addition to a very safe prevention strategy before neonatal screening programmes may be instituted.

Viruses and other perinatal exposures as initiating events for beta-cell destruction

There is strong evidence that the aetiology of insulin-dependent diabetes mellitus (IDDM) is due to a complex interaction between genes and the environment and that the pathogenesis is autoimmune. In early perinatal life the immune system is induceable and exposures in this period may initiate autoimmunity. Recent findings of time and space clustering of birth dates for later diabetic cases together with the early observation of a very high prevalence of diabetes in cases with rubella embryopathy suggest that foetal virus exposure may be important. Recent findings from Sweden and Finland suggest that enterovirus exposure during foetal life may initiate autoimmunity which may lead to diabetes. Other immune events, such as maternal-foetal blood group incompatibility and pre-eclampsia in the mother have also been associated with IDDM risk. Other more unspecific events in the perinatal period, such as a short gestational age, caesarean section and neonatal respiratory disease, are also indicated to increase the risk. In addition, food components such as nitrosamine components, cow's milk protein and gliadin have been proposed to initiate the slowly progressing autoimmune beta-cell destruction. Most of these epidemiological findings are supported by experimental studies in the nonobese diabetic mice but their exact mechanisms of action are still unclear. It is concluded that new evidence is accumulating indicating that perinatal exposures may be important for the initiation of beta-cell destruction. As such risk factors may be targets for primary prevention strategies further studies are urgently warranted.

Early neonatal events and the disease incidence in nonobese diabetic mice

Epidemiologic studies have shown that perinatal events are associated with an increased risk for type 1 (insulin-dependent) diabetes in childhood. We used nonobese diabetic mice to examine whether neonatal separation from the mother with or without phototherapy would affect the incidence of diabetes in this genetically susceptible mouse model. The newborn pups were taken from their mothers for two 4-h periods during each of five successive days. One group of animals was just taken from their mothers and were left lying in daylight in the cage, whereas another group was exposed to identical light as used for treatment of neonatal jaundice in infants. Treatment resulted in a 30% death rate. For animals surviving more than 3 mo the incidence of diabetes was significantly higher in both treatment groups compared with control animals, allowed to stay with their mother. The odds ratio for treatment versus control, stratifying for sex, was 3.42 (95% confidence interval, 1.57-7.74). Histologic insulitis did not differ between treated and untreated animals when examined either at clinical diabetes onset or at 8 mo of age. Blood glucose values at 8 mo of age (in animals without clinical diabetes) did not differ between-treated and untreated animals. It is concluded that neonatal separation of the nonobese diabetic mice from their mothers will lead to a significantly increased risk for diabetes. This increase in risk seems to be associated with the induction of metabolic alterations leading to increased peripheral insulin need rather than with an increased rate of beta cell destruction.

Epidemiology of childhood IDDM in Northern Ireland 1989-1994: low incidence in areas with highest population density and most household crowding. Northern Ireland Diabetes Study Group

During the period 1989-1994, 462 cases of insulin-dependent diabetes mellitus were registered among children from Northern Ireland aged under 15 years. The estimated completeness of the register was 98.8% (95% confidence interval (CI) 97.7%, 99.9%). A standardised rate of 19.6 (95% CI 17.8, 21.4) per 100 000 person years was obtained, placing Northern Ireland near the top of the range of published incidence in the United Kingdom, with a rate close to that reported for Scotland. In an analysis based on 217 postcode sectors, areas with a high population density and the most material deprivation were observed to have the lowest incidence rates. After inclusion of population density in a Poisson regression analysis, the component of deprivation which was found to be most significant was household crowding. Relative to children living in areas of low population density, there was a reduced risk for children in medium (relative incidence 0.85 (95% confidence limits CI 0.67, 1.09)) and high (0.62 (95% CI 0.48,0.80)) population density areas. Similarly, relative to children living in areas with low levels of household crowding, there was a reduced risk for children in medium (relative incidence 0.73 (95% CI 0.58,0.93)) and high (0.67 (95% CI 0.53, 0.83)) levels of household crowding. Tests for space-time clustering at diagnosis and at birth were negative. A possible explanation for the differences in incidence rate observed in this study is that exposure to infections very early in childhood is a protective factor. Later infections may act as either initiators or promoters of diabetes, but the absence of space-time clustering suggests that no single specific infectious agent is responsible.

Environmental and experimental procedures leading to variations in the incidence of diabetes in the nonobese diabetic (NOD) mouse

Environmental factors appear to be nongenetic risks of importance in the progression of insulin-dependent diabetes mellitus (IDDM) or type 1 diabetes, whose mechanisms are not yet well understood. Stressful life events, in particular, have been linked to the expression of overt diabetes in humans. However, in rodent models of IDDM, contradictory data exist concerning the effects of stress on the disease. Here, we show that a stressor, such as long-term repeated injections of vehicle (0.9% saline), was able to delay the appearance and/or decrease the incidence of diabetes in both sexes of NOD mice. Short-term chronic stress applied from the 6th to the 8th week of age by a combination of multiple stressors (overcrowding + immobilization + cold exposure + anesthesia) protected NOD mice from diabetes, particularly males. In contrast, prenatal stress, induced by immobilization of the mothers during the third part of pregnancy, accelerated the onset and increased the prevalence of diabetes at 30 weeks of age in NOD females, while it had no effect in males. Finally, adrenalectomy appears to aggravate the development of diabetes in NOD mice, particularly in males. In conclusion, these data demonstrate that the appearance of diabetes in NOD mice is extremely sensitive to various experimental and environmental conditions. These results are discussed in the context of the complex neuroendocrine-immune interactions which occur during the progression of IDDM, with a particular focus on glucocorticoids and cytokines.

Psychoneuroimmunology of autoimmune disorders

The interactions between the immune system and psychological states are both intricate and intriguing. Research at a molecular level has thrown considerable light on the previously ill-defined area of psychoneuroimmunology. In this report, we explore the psychoneuroimmunology of autoimmune disorders, particularly rheumatoid arthritis and lupus erythematosus. Animal models of these diseases have provided a particularly useful window on complex psychoneuroimmunological interactions. Observations about the effect of stress on the onset and course of autoimmune disorders has added to our understanding of psychoneuroimmunological interactions. These interactions are bi-directional, as reflected in the autoimmune-mediated neuropsychiatric manifestations of systemic lupus. Exploring the role of various neurotransmitters and neuromodulators in the stress response may have important therapeutic implications for autoimmune disorders.