Epidemiology of childhood type I diabetes in Sudan, 1987-1990

Psychosocial Impact of Sickle Cell Disease and Diabetes Mellitus on Affected Children and Their Parents in Khartoum State, Sudan

This study aimed to assess the psychosocial impact of sickle cell disease (SCD) and diabetes mellitus on children and their parents in Sudan, and the relationship between socioeconomic status and psychosocial issues. A descriptive, cross-sectional study was conducted among n = 320 children aged 6-12 years, of whom n = 170 were diagnosed with SCD, n = 150 children with diabetes mellitus and their parents. The strengths and difficulties questionnaire (SDQ scale) was used to assess the psychosocial aspect of children. Depression, Anxiety, Stress Scale -21 Items (DASS 21) was used to assess the psychological well-being of the caregivers. Data on psychological problems of children with SCD showed that 66.5% had emotional symptoms, 18.2% had conduct problems and 19.4% hyperactivity. Data of parents showed that 45.9% of parents did not experience depression; 27.9% were moderately depressed group. Data on psychological problems among children with diabetes showed that 57.3% experienced emotional symptoms, conduct problems were close to the average among 66%. Data on psychological problems among parents of children with diabetes showed that 45.3% of parents did not experience depression; 22.7% belonged to the moderately depressed group. Psychosocial problems were common both among children and parents. More research is needed in the context of caring for a child with chronic diseases and the role of health care providers in adapting and mitigating psychological problems among both parents and children.

Sociodemographic determinants of glycaemic control among children with type 1 diabetes in South Eastern Nigeria

INTRODUCTION

diabetic complications have been identified as the major causes of morbidity and mortality in persons with type 1 diabetes mellitus (T1DM). Lack of appropriate glycaemic control is a significant risk factor for the onset and progression of long term complications of diabetes. Identifying the determinants of good glycaemic control is therefore imperative.

METHODS

this was a cross-sectional, hospital-based study of children aged 3-18 years with T1DM. Subjects were consecutively enrolled after obtaining consent from their parents and assent from children aged ≥7 years. A questionnaire was completed recording their clinical history and sociodemographic variables. Their HbA1c was estimated and values ≤7.5% was defined as the cut-off for optimal glycaemic control.

RESULTS

seventy-one children with T1DM were enrolled for the study. Thirty-eight (53.5%) of them were males. Mean age (years) was 13.7±4. Mean age at onset of diabetes was 11.6 years (range: 3-16 years), mean duration of diabetes was 24.4 months (range: 4-84 months), mean HbA1c value was 10.5% (range: 6.4%-14%); a multivariate logistic regression analysis was performed to identify determinants of optimal glycaemic control. Only caregivers' involvement in diabetes management P<0.016, odd ratio 13.03 (95% CI: 1.60-105.95) was identified as determinant of good glycaemic control.

CONCLUSION

our data suggest that of all the sociodemographic factors studied, caregivers' involvement in diabetes management was the only strong determinant for optimal glycaemic control.

Very High Incidence of Type 1 Diabetes Among Children Aged Under 15 Years in Tlemcen, Northwest Algeria (2015-2018)

OBJECTIVE

In Algeria, there is a lack of epidemiological data concerning childhood type 1 diabetes (T1D). The International Diabetes Federation estimated in 2019 that Algeria ranked 7^th among countries with the highest prevalence of T1D. This study aimed to determine the incidence of T1D in children <15 years, living in Tlemcen in Northwest Algeria.

METHODS

A retrospective study using data from children (<15 years) who have been diagnosed with T1D in Tlemcen between 2015 and 2018, using the two-source capture–recapture method to estimate the completeness of ascertainment (%). Total average incidences, by sex, by onset age group, and by season of onset were calculated per 100,000 and per year.

RESULTS

During the study period, 437 new cases of T1D were registered, among them, 233 boys and 204 girls, with a sex ratio of 1.14. The average annual incidence rate of childhood T1D was 38.5/100,000 with a 95% confidence interval (CI): 35.20-41.79; boys: 40.51, 95% CI: 38.16-42.85; girls: 36.49, 95% CI: 34.17-38.80. Overall incidence rates in 2015, 2016, 2017 and 2018 were respectively 36.6 (95% CI: 33.72-39.48), 38.7 (95% CI: 35.43-41.97), 39.3 (95% CI: 35.97-42.62) and 39.5 (95% CI: 36.12-42.87)/100,000. Newly diagnosed children were more likely to present in winter and autumn. Ketoacidosis at diagnosis was diagnosed in 29.2%.

CONCLUSION

The mean incidence of childhood T1D in Tlemcen was 38.5/100,000, this incidence is in the “extremely high” category of the World Health Organization DiaMond project classification of diabetes giving this region a very high risk.

Morbidity and Complications of Diabetes Mellitus in Children and Adolescents in Ghana: Protocol for a Longitudinal Study

Background

Diabetes is associated with premature morbidity and mortality from its many complications. There are limited data on the chronic complications of diabetes in children and adolescents in sub-Saharan Africa.

Objective

The study aims to determine the (1) burden and related factors of chronic systemic complications of diabetes, including diabetic and nondiabetic ocular conditions in children and adolescents, and (2) quality of life (QoL) of participants compared to healthy controls. This manuscript describes the study methodology.

Methods

Demographic information, medical history, anthropometric measurements, and laboratory characteristics were collected, and the participants were screened for microvascular and macrovascular complications as well as nondiabetic ocular disease. QoL questionnaires were administered to participants, their caregivers, and controls. Participants were followed up annually up to 3 years to determine the natural history of and trends in these conditions. SPSS Version 25.0 will be used for data analysis. Continuous and categorical data will be presented as mean (SD) and as percentages (%), respectively. t tests and analysis of variance will be used to compare means, and chi-square tests will be used to compare categorical data. Correlation, regression, and logistic regression analyses will be employed to establish linear associations and causal associations as appropriate. Relative risk and odds ratios will be used to estimate risk. QoL outcomes in Ghanaian children and adolescents with diabetes mellitus compared with caregivers and healthy controls will be assessed using the Pediatric Quality of Life inventory. Significance will be set at α=.05.

Results

Institutional approval from the Ethical and Protocol Review Committee of the University of Ghana Medical School was received on August 22, 2014 (Protocol Identification Number: MS-Et/M.12-P4.5/2013-2014). Funding for the project was received from the University of Ghana Research Fund (#UGRF/9/LMG-013/2015-2016) in March 2016. Patient recruitment, clinical examination, and data collection commenced in August 2016 and was completed in September 2019. A total of 58 children and adolescents with diabetes mellitus have been recruited. Blood samples were stored at –80 °C for analysis, which was completed at the end of July 2020. Data analysis is ongoing and will be completed by the end of December 2020. Investigators plan to submit the results for publication by the end of February 2021.

Conclusions

The prevalence, natural history, trends in diabetic complications and nondiabetic ocular disease, and QoL will be provided. Our data may inform policies and interventions to improve care given to children and adolescents with diabetes.

International Registered Report Identifier (IRRID)

DERR1-10.2196/21440

Incidence and prevalence of type 1 diabetes mellitus in children and adolescents aged 6 months-19 years in Khartoum State, Sudan

The aim of this study is to measure the incidence and prevalence of type 1 diabetes mellitus in children and adolescents in Khartoum State, Sudan. Records of all patients aged 6 months-19 years, living in Khartoum State and who were known to have or newly diagnosed with type 1 diabetes in all health institutes (both governmental and private) during the period January to December 2015, were reviewed. In addition to the records, interviews with patients and caregivers attending the clinics were conducted. Names were double-checked with the Sudanese Childhood Diabetes Association's central registry. Data were analysed using the Statistical Package for the Social Sciences software (SPSS 20). A total of 2,393 children were identified. Males were 1,117 (46.6%) and females were 1,276 (53.3%) with a ratio of 1:1.4, with no significant difference. The prevalence rate was 0.74/1,000. The overall incidence rate was 10.1/100,000. The peak incidence age was between 11 and 15 years (15.9/100,000). The incidence rates in below 5 years and 16-19 years were 8.4 and 7.7/100,000, respectively. There was no significant difference between males and females. In most of the cases, the onset was in the winter months. The commonest month of birth was June.The incidence of type 1 diabetes in Sudan is still considered among the high rate group in the world and in the region. There was an obvious increase in the incidence among the below-5 years age group (8.4/100,000) compared to a figure of 3.5 which was reported earlier from Sudan. For the first time, we report the incidence among the 16-19 age group (7.7/100,000).

Hearing loss in type 1 diabetes: Are we facing another microvascular disease? A meta-analysis

OBJECTIVE

Evidence shows type 1 diabetes(T1D) leads to vascular damage and neuropathy. The purpose of this study was to perform a systematic review and a meta-analysis to assess the evidence of the effects of T1D on hearing function.

METHODS

Three electronic databases were used. The articles were independently reviewed by two authors using predefined inclusion criteria to identify eligible studies. They were then classified as high or low methodological quality. Meta-analysis was performed on pooled data of hearing loss(HL) prevalence, pure tone audiometry(PTA), otoacoustic emissions(OAE) and auditory brainstem response(ABR).

RESULTS

Twenty-one articles fulfilled the inclusion criteria. In all studies, HL was defined as pure tone greater than 20 dB in at least one frequency. The prevalence of HL ranged between 5.17% and 48% for diabetics, which was higher than in controls which ranged between 0% à 40% (OR = 7.7, 95% CI 3.32-17.98, p < 0.05 and I² = 40%). The tendency of mean thresholds of PTA was higher in diabetics than in controls, with results being statistically significant at 250, 500 and 1000 Hz. OAE were significantly lower in diabetic patients. ABR latencies were longer in T1D group compared to controls and were statistical significant.

CONCLUSIONS

Patients with T1D have a significantly greater prevalence of HL compared to the control group. These damages could be compared to other microvascular diseases. Further studies are needed to assess whether hearing testing should be considered as a part of the screening process in T1D patients and therefore, secondary preventive treatment may be warranted as well.

Prevalence of nephropathy in type 1 diabetes in the Arab world: A systematic review and meta-analysis

The aim of this study was to conduct a systematic review and meta-analysis and determine the prevalence of diabetic nephropathy (DN) among Arab patients with T1D. A systematic literature search was conducted using 4 different literature databases (PubMed, ScienceDirect, Web of Science, and Embase) to capture all relevant data about Arab patients with T1D that had DN. Meta-analysis and systematic review were performed using the random effect model, and the heterogeneity of the studies was assessed using the Q-test, I2, and Tau-squared statistics. Publication bias was assessed using the funnel-plot test. Our search strategy captured 372 studies in only 10 out of the 22 Arab countries in a period of 48 years (1969-2017); of which, 41 met our inclusion criteria for full article analysis, of those, 15 were eligible for meta-analysis. We estimated the prevalence of DN among Arab people with T1D to be 18.2% (95% confidence interval 13.1%-24.8%). In conclusion, DN prevalence is underexplored among Arab patients with T1D and represents a significant risk for the well-being of Arab patients with T1D. Therefore, there is an urgent need for comprehensive epidemiological studies for DN among Arab patients with T1D.

Climates on incidence of childhood type 1 diabetes mellitus in 72 countries

We are aimed to systematically assess the worldwide trend in incidence of childhood type 1 diabetes mellitus (CT1DM) from 1965 to 2012 and to discuss whether climate affect incidence of CT1DM. We searched the relevant literatures in detail to judge the effect of different climates on incidence of CT1DM. The climates included Mediterranean, monsoon, oceanic, continental, savanna, and rainforest. According to different climates, we further researched relevant factor such as sunshine durations and latitudes. The overall incidence of CT1DM in 72 countries was 11.43 (95% CI 10.31–12.55) per 100,000 children/yr. The incidence of CT1DM in Oceanic climate [10.56 (8.69–12.42)] is highest compared with other climates; the incidence in 40°–66°34′N/S [14.71 (12.30–17.29)] is higher than other latitude groups; the incidence in sunshine durations with 3–4 hours per day [15.17 (11.14–19.20)] is highest compared with other two groups; the incidence of CT1DM from 2000 to 2012 [19.58 (14.55–24.60)] is higher than other periods; all p < 0.01. Incidence of CT1DM was increasing from 1965 to 2012, but incidence in Oceanic climate is higher than other climates. Furthermore, it is higher in centers with higher latitude and lower sunshine durations. The climates might play a key role in inducing CT1DM.

Glycemic Control in Kenyan Children and Adolescents with Type 1 Diabetes Mellitus

Background. Type 1 diabetes mellitus (T1DM) is the most common endocrine disorder in children and adolescents worldwide. While data about prevalence, treatment, and complications are recorded in many countries, few data exist for Sub-Saharan Africa. The aim of this study was to determine the degree of control in patients with T1DM aged 1-19 years over a 6-month period in 3 outpatient Kenyan clinics. It also sought to determine how control was influenced by parameters of patient and treatment. Methods. Eighty-two children and adolescents with T1DM were included in the study. Clinical history regarding duration of illness, type and dose of insulin, and recent symptoms of hypoglycemia/hyperglycemia were recorded. Glycaemia, HbA1c, and ketonuria were tested. HbA1c of 8.0% and below was defined as the cut-off for acceptable control. Results. The median HbA1c for the study population was 11.1% (range: 6.3-18.8). Overall, only 28% of patients had reasonable glycemic control as defined in this study. 72% therefore had poor control. It was also found that age above 12 years was significantly associated with poor control. Conclusions. African children and with T1DM are poorly controlled particularly in adolescents. Our data strongly support the necessity of Kenya children to receive more aggressive management and follow-up.

Prevalence and incidence of clinically recognized cases of Type 1 diabetes in children and adolescents in Rwanda, Africa

AIMS

To determine prevalence and incidence estimates for clinically recognized cases of Type 1 diabetes from the Life For a Child Program (LFAC) with onset < 26 years in six representative districts, and the capital, of Rwanda.

METHODS

Cases were identified from the LFAC registry and visits to district hospitals. Denominators were calculated from district-level population surveys. Period prevalence data were collected from 1 August 2011 to 31 July 2012 and annual incidence rates were calculated, retrospectively, for 2004-2011. Ninety-five per cent confidence intervals (95% CI) were calculated using a Poisson distribution.

RESULTS

The prevalence of known Type 1 diabetes in seven districts in Rwanda for ages < 26 years was 16.4 [95% CI 14.6-18.4]/100 000 and for < 15 years was 4.8 [3.5-6.4]/100 000. Prevalence was higher in females (18.5 [15.8-21.4]/100 000) than males (14.1 [11.8-16.7]/100 000; P = 0.01) and rates increased with age. The annual incidence rate for those < 26 years was stable between 2007 and 2011 with a mean incidence over that time of 2.7 [2.0-3.7]/100 000 ( < 15 years = 1.2 [0.5-2.0]/100 000). Incidence rates were higher in females than males and peaked in males at ages 17 and 22 years and in females at age 18 years.

CONCLUSIONS

Our report of known Type 1 diabetes cases shows lower incidence and prevalence rates in Rwanda than previously reported in the USA and most African countries. Incidence of recognized cases has increased over time, but has recently stabilized. However, the likelihood of missed cases due to death before diagnosis and misdiagnosis is high and therefore more definitive studies are needed.

Prevalence of diabetes in Zimbabwe: a systematic review with meta-analysis

OBJECTIVE

Diabetes appears to be a growing problem in the African region. This study aims to estimate the prevalence of diabetes in Zimbabwe by collating and analyzing previously published data.

METHODS

Systematic review and meta-analysis of data reporting prevalence of diabetes in Zimbabwe was conducted based on the random effects model. We searched for studies published between January 1960 and December 2013 using MEDLINE, EMBASE and Scopus and University of Zimbabwe electronic publication libraries. In the meta-analysis, sub-groups were created for studies conducted before 1980 and after 1980, to understand the potential effect of independence on prevalence.

RESULTS

Seven studies were included in the meta-analysis with a total of 29,514 study participants. The overall pooled prevalence of diabetes before 1980 was 0.44% (95% CI 0.0-1.9%), after 1980 the pooled prevalence was 5.7% (95% CI 3.3-8.6%).

CONCLUSIONS

This study showed that the prevalence of diabetes in Zimbabwe has increased significantly over the past three decades. This poses serious challenges to the provision of care and prevention of disabling co-morbidities in an already disadvantaged healthcare setting.

Trends in the incidence of type 1 diabetes among Jews and Arabs in Israel

OBJECTIVE

To assess the trends in the incidence of type 1 diabetes between 1997 and 2010 among 0-17-yr-old Israeli Jews and Arabs compared with global trends.

METHODS

Data on children with newly diagnosed type 1 diabetes reported by pediatric endocrinologists from 19 medical centers to the Israel Center for Disease Control, as part of the National Diabetes Register.

RESULTS

During 1997-2010, 2857 Jews and 757 Arabs were diagnosed with type 1 diabetes. The average age-adjusted incidence among Jews was higher than Arabs [12.2 per 100 000, 95% confidence interval (CI) 10.5-14.2 and 8.9 per 100 000, 95% CI 7.5-10.7, p = 0.0001, respectively], however, the annual percent change was higher for Arabs compared with Jews (4.0 vs. 3.6%, p = 0.005, respectively). The mean age at diagnosis was similar for Jews and Arabs (9.6 ± 4.4 vs. 9.9 ± 4.4 yr, p = 0.08), and it remained stable during 1997-2010 in both ethnic groups (p = 0.6). In both Jews and Arabs the highest annual percent change was observed in younger children. It was 4.9% for children aged 5-9 yr and 10.7% for children aged 0-4 yr, respectively. There were no differences in the frequency of diabetic ketoacidosis (DKA) between Jews (39.9%) and Arabs (41.3%), (p = 0.5).

CONCLUSION

Type 1 diabetes incidence of Jews and Arabs in Israel is increasing. The incidence is higher in Jews than in Arabs; however, the annual percent change is higher in Arabs than in Jews. In both Ethnic groups the incidence of type 1 diabetes is increasing especially among young children.

Epidemiology of childhood type 1 diabetes mellitus in Nile Delta, northern Egypt - a retrospective study

OBJECTIVE

The geographical incidence of type 1 diabetes mellitus (T1DM) varies widely worldwide. Both genetic and environmental factors have been implicated, although environmental factors are still speculative and elusive. More epidemiological studies are needed to uncover such factors. To date, there are no reported studies on the epidemiology of childhood T1DM in Nile Delta, Egypt. We aimed to define the incidence, prevalence and demographic characteristics of T1DM in children (0-18 years) living in the Nile Delta region, one of the most densely populated areas in Egypt.

METHODS

The study included all T1DM patients aged 0-18 years who lived in the Nile Delta region of Egypt and who were either diagnosed at or referred to Mansoura University Children's Hospital (MUCH) between 1 January 1994 and 31 December 2011. The hospital files of the patients were reviewed. General population data on the 0-18 year age group in the Nile Delta governorates were also presented.

RESULTS

From a total of 1600 T1DM patients, 891 (55.7%) were females (p=0.000) and 935 (58.4%) were from rural areas (p=0.000). Calculated age-adjusted incidence of T1DM in 1996, 2006 and 2011 were 0.7, 2.0 and 3.1/10(5)/year, respectively, while calculated age-adjusted prevalence of T1DM in the same years were 1.9, 15.5 and 26.8/10(5)/year, respectively. Patients presented most frequently in the 5-10 year age group (p<0.000) and in winter months (p=0.009).

CONCLUSION

In this first childhood T1DM epidemiology study in the Nile Delta region of Egypt, T1DM incidence and prevalence were found to show an increase over the past 18 years (1994-2011). Incidence and prevalence were higher in females and more cases were found to originate from rural areas.

Current clinical status, glucose control, and complication rates of children and youth with type 1 diabetes in Rwanda

OBJECTIVE

To describe the clinical status of youth and adolescents (≤ 25 yr) in the Rwanda Life For A Child (LFAC) program who had their first HbA1c measure in 2009 or 2010, and to identify factors which may relate to glycemic control (HbA1c) and complication status.

RESEARCH DESIGN AND METHODS

Data were collected from June 2009 to November 2010 for the LFAC program in Rwanda and comprise clinical data from when participants' first HbA1c reading was obtained.

RESULTS

From June 2009 to November 2010, 286 youth aged ≤25 yr had their first HbA1c. Mean age, duration, and age at diagnosis were 18.6 ± 4.5 yr, 3.4 ± 3.1 yr and 15.1 ± 4.8 yr, respectively. Mean HbA1c was 11.2 ± 2.7% with 15.7% (n = 45) having HbA1c <8%, while 30.8% (n = 88) had HbA1c >14%. Five (2.1%) had either abnormal tuning fork vibratory sensation or monofilament response, 21% (n = 31) had microalbuminuria (MA, A/C ratio >30 mg/g) and 5% (n = 7) had nephropathy (A/C ratio >300 mg/g). Diabetes duration and insulin dose/kg were positively associated with higher HbA1c, while residing in the southern province was associated with lower HbA1c. Duration, diastolic blood pressure, and HbA1c were positively associated with developing MA, while age was protective.

CONCLUSIONS

These data from the LFAC program for 2009-2010 show that there is a urgent need for dramatically improved care, as many patients have greatly elevated HbA1c measures, often >14%. We have identified correlates of better control (e.g., living in the Southern province) and MA (e.g., diastolic blood pressure), which provide potential avenues to improved quality of care.

A systematic overview of prospective cohort studies of cardiovascular disease in sub-Saharan Africa

Background

Cardiovascular diseases (CVDs) are becoming increasingly significant in sub-Saharan Africa (SSA). Reliable measures of the contribution of major determinants are essential for informing health services and policy solutions.

Objective

To perform a systematic review of all longitudinal studies of CVDs and related risk factors that have been conducted in SSA.

Data source

We searched electronic databases from 1966 to October 2009. Published studies were retrieved from PubMed and Africa EBSCO. Reference lists of identified articles were scanned for additional publications.

Study selection

Any longitudinal study with data collection at baseline on major cardiovascular risk factors or CVD, including 30 or more participants, and with at least six months of follow up were included.

Data extraction

Data were extracted on the country of study, year of inception, baseline evaluation, primary focus of the study, outcomes, and number of participants at baseline and final evaluation.

Results

Eighty-one publications relating to 41 studies from 11 SSA countries with a wide range of participants were included. Twenty-two were historical/prospective hospital-based studies. These studies focused on risk factors, particularly diabetes mellitus and hypertension, or CVD including stroke, heart failure and rheumatic heart disease. The rate of participants followed through the whole duration of studies was 72% (64–80%), with a significant heterogeneity between studies (for heterogeneity, p < 0.001). Outcomes monitored during follow up included trajectories of risk markers and mortality.

Conclusions

Well-designed prospective cohort studies are needed to inform and update our knowledge regarding the epidemiology CVDs and their interactions with known risk factors in the context of common infectious diseases in this region.

Quality assessment of capture-recapture studies in resource-limited countries

OBJECTIVES

Resource-limited countries often lack robust routine surveillance systems to accurately assess the burden of human attributes and diseases. In these settings capture-recapture analysis can be an alternative tool to obtain prevalence and incidence rates. Performance of capture-recapture analyses in resource-limited countries has not been systematically reviewed.

METHODS

Systematic review of the performance of capture-recapture analyses in the categories of human attributes, non-infectious and infectious diseases in resource-limited countries, assessing individual study quality criteria and a minimum quality criterion per category, using PRISMA methodology.

RESULTS

A total of 1671 potentially relevant PubMed citations were screened, resulting in 52 eligible publications: 36% in human attributes, i.e. hidden populations, injuries and mortality; 48% in non-infectious and 15% in infectious disease categories. Twenty-one per cent of selected studies were from low income countries, 40% from lower-middle-income countries and 38% from upper-middle-income countries. Thirteen per cent achieved good individual study quality criteria, 25% were intermediate and 19% were poor. Of the good studies, six were performed on human attributes and one on a non-infectious disease. The proportions of publications meeting the minimum quality criterion per category were 42%, 20% and 37%, respectively.

CONCLUSIONS

Few capture-recapture studies in resource-limited countries achieved good individual quality criteria and a minority met the minimum quality criterion per category. Capture-recapture techniques in these settings should be carefully considered and implemented rigorously and are not a panacea for strengthening of routine surveillance systems.

Immunological and C-peptide studies of patients with diabetes in northern Ethiopia: existence of an unusual subgroup possibly related to malnutrition

AIMS/HYPOTHESIS

Surveys in northern Ethiopia have demonstrated that apparent type 1 diabetes occurs more frequently than elsewhere in Africa and, indeed, in other parts of the world. We therefore investigated in detail a cohort of diabetic patients from this region to clarify the nature of this type of diabetes.

METHODS

All patients attending the diabetic clinic at Mekelle Hospital in the Tigray region of northern Ethiopia were investigated over a 6 week period. Clinical, demographic and anthropometric data were collected, as well as measurements of HbA(1c), fasting lipid profile, fasting serum C-peptide and serum markers of beta cell autoimmunity, i.e. islet antigen-2 and GAD antibodies (GADA).

RESULTS

Of 105 patients seen, 69 (66%) were on insulin treatment and had been from or close to diagnosis. Their median age and diabetes duration were 30 and 5 years, respectively, with a male excess of 2:1. Median BMI was 20.6 kg/m². Despite these clinical characteristics suggestive of type 1 diabetes, only 42 of 69 (61%) patients were C-peptide-negative and 35% GADA-positive. Overall, 38 (36%) of the total group (n = 105) had immunological or C-peptide characteristics inconsistent with typical type 1 or type 2 diabetes. The clinical characteristics, local prevalence of undernutrition, and GADA and C-peptide heterogeneity suggest a malnutrition-related form of diabetes.

CONCLUSIONS/INTERPRETATION

Not all patients in northern Ethiopia with apparent type 1 diabetes appear to have the form of disease seen in Europids; their disease may, in fact, be related to malnutrition.

Diabetes in sub-Saharan Africa

In Sub-Saharan Africa, prevalence and burden of type 2 diabetes are rising quickly. Rapid uncontrolled urbanisation and major changes in lifestyle could be driving this epidemic. The increase presents a substantial public health and socioeconomic burden in the face of scarce resources. Some types of diabetes arise at younger ages in African than in European populations. Ketosis-prone atypical diabetes is mostly recorded in people of African origin, but its epidemiology is not understood fully because data for pathogenesis and subtypes of diabetes in sub-Saharan African communities are scarce. The rate of undiagnosed diabetes is high in most countries of sub-Saharan Africa, and individuals who are unaware they have the disorder are at very high risk of chronic complications. Therefore, the rate of diabetes-related morbidity and mortality in this region could grow substantially. A multisectoral approach to diabetes control and care is vital for expansion of socioculturally appropriate diabetes programmes in sub-Saharan African countries.

Gene therapy in diabetes

Type 1 diabetes (T1D) is a chronic autoimmune disease, whereby auto-reactive cytotoxic T cells target and destroy insulin-secreting β-cells in pancreatic islets leading to insulin deficiency and subsequent hyperglycemia. These individuals require multiple daily insulin injections every day of their life without which they will develop life-threatening diabetic ketoacidosis (DKA) and die. Gene therapy by viral vector and non-viral transduction may be useful techniques to treat T1D as it can be applied from many different angles; such as the suppression of autoreactive T cells to prevent islet destruction (prophylactic) or the replacement of the insulin gene (post-disease). The need for a better method for providing euglycemia arose from insufficient numbers of cadaver islets for transplantation and the immunosuppression required post-transplant. Ectopic expression of insulin or islet modification have been examined, but not perfected. This review examines the various gene transfer methods, gene therapy techniques used to date and promising novel techniques for the maintenance of euglycemia in the treatment of T1D.

Insulin-requiring diabetes in rural Ethiopia: should we reopen the case for malnutrition-related diabetes?

AIMS/HYPOTHESIS

We evaluated the incidence of insulin-requiring diabetes in a rural area of sub-Saharan Africa.

METHODS

Health surveillance data from a chronic disease programme in two zones of Ethiopia, Gondar and Jimma, were studied. The two zones have a population of more than 5,000,000 people.

RESULTS

In Gondar Zone (1995-2008) and Jimma Zone (2002-2008) 2,280 patients presented with diabetes, of whom 1,029 (45%) required insulin for glycaemic control at diagnosis. The annual incidence of insulin-requiring diabetes was 2.1 (95% CI 2.0-2.2) per 100,000 and was twice as high in men (2.9 per 100,000) as in women (1.4 per 100,000). In both sexes incidence rates peaked at the age of 25 to 29 years. Incidence rates in the urban areas of Gondar and Jimma were five times higher than in the surrounding rural areas. Patients with insulin-requiring diabetes from rural and urban areas had a very low BMI and most were subsistence farmers or unemployed.

CONCLUSIONS/INTERPRETATION

The typical patient with diabetes in rural Ethiopia is an impoverished, young adult male with severe symptoms requiring insulin for glycaemic control. The low incidence rates in rural compared with urban areas suggest that many cases of this disease remain undiagnosed. The disease phenotype encountered in this area of Africa is very different from the classical type 1 diabetes seen in the West and most closely resembles previous descriptions of malnutrition-related diabetes, a category not recognised in the current WHO Diabetes Classification. We believe that the case for this condition should be reopened.

A sub-Saharan African perspective of diabetes

Diabetes mellitus is an important and increasing cause of morbidity and mortality in sub-Saharan Africa. Accurate epidemiological studies are often logistically and financially difficult, but processes of rural-urban migration and epidemiological transition are certainly increasing the prevalence of type 2 diabetes. Type 1 disease is relatively rare, although this may be related to high mortality. This diabetic subgroup appears to present at a later age (by about a decade) than in Western countries. Variant forms of diabetes are also described in the continent; notably 'atypical, ketosis-prone' diabetes, and malnutrition-related diabetes mellitus. These types sometimes make the distinction between type 1 and type 2 diabetes difficult. Interestingly, this is also a current experience in the developed world. As more detailed and reliable complication studies emerge, it is increasingly apparent that African diabetes is associated with a high complication burden, which is both difficult to treat and prevent. More optimistically, a number of intervention studies and twinning projects are showing real benefits in varying locations. Future improvements depend on practical and sustainable support, coupled with local acceptance of diabetes as a major threat to the future health and quality of life of sub-Saharan Africans.

Diabetes care in sub-Saharan Africa

The increasing numbers of people with type 2 diabetes is a worldwide concern. It presents an added challenge in sub-Saharan Africa, where diabetes must compete for resources with communicable diseases. A scarcity of financial resources and appropriate staff mean that many people with type 2 diabetes have complications and that those with type 1 diabetes have an extremely short life-expectancy, whether or not they have been diagnosed with the disorder. We review the current evidence on diabetes care in sub-Saharan Africa and propose an 11-point action plan to address this problem in the region.

Growth, puberty, and final height in children with Type 1 diabetes

OBJECTIVE

The aims of this study were to assess the physical growth and pubertal development in a group of diabetic children and to evaluate the effect of height at diagnosis, duration of illness, and degree of glycemic control on final height and sexual maturation.

RESEARCH DESIGN

A cohort of 72 Sudanese diabetic children, 7-13 years of age at diagnosis, was followed longitudinally from the onset of diabetes until the attainment of final height.

RESULTS

The mean height standard deviation scores (SDS) at diagnosis were 0.04 in boys and -0.15 in girls, which was greater than their genetic target height (GTH). The growth velocity between diagnosis and final height was slow, with significant reduction in pubertal growth spurt. The mean final height attained by these children was lower than their GTH, a finding that contradicts most of the recently published reports. The average age at menarche in girls (15.1 years) and the mean age of full sexual maturation in boys (17.2 years) were significantly delayed in this group of diabetic patients. This retardation in physical growth and pubertal development was positively correlated with the duration of diabetes before the onset of puberty and glycated haemoglobin (HbA1c) concentration. The majority of these patients were thin at diagnosis of diabetes, with median body mass index (BMI) <22, but showed a remarkable, progressive weight gain during puberty, which was more evident in girls. The weight gain was independent of weight at diagnosis and duration of diabetes, but was positively correlated with the daily dose of insulin and HbA1c concentration.

CONCLUSION

Conventional therapy of diabetic children is associated with impairment of physical growth and delayed sexual maturation.

Cardiovascular complications of diabetes mellitus in sub-Saharan Africa

BACKGROUND

Cardiovascular disease, the major cause of mortality and morbidity in modern societies, is set to overtake infectious diseases in the developing world as the most common cause of death. The increasing prevalence of major and emerging cardiovascular risk factors accounts for the growing burden of cardiovascular disease in the world. Diabetes in all its forms is one of the main cardiovascular risk factors. Two of 3 diabetic patients will die as a result of cardiovascular complications, and approximately 30% of patients treated in cardiovascular intensive care units have diabetes.

METHODS AND RESULTS

This review on the cardiovascular complications of diabetes in sub-Saharan Africa is a bibliographical MEDLINE search of published data over the past 2 decades. Diabetes-related cardiovascular disease complications are considered to be rare in Africa but are on the rise and are regularly associated with classic cardiovascular risk factors. Coronary heart disease may affect 5% to 8% of type 2 diabetic patients and cardiomyopathy, up to 50% of all patients. Close to 15% of patients with stroke have diabetes, and up to 5% of diabetic patients present with cerebrovascular accidents at diagnosis. Peripheral vascular disease prevalence varies across sites from 4% to 28%.

CONCLUSIONS

It is obvious that diabetes mellitus and related cardiovascular complications are gaining more importance in sub-Saharan Africa. The relative contribution of putative risk factors is not well defined, and further research is therefore needed.

Diabetes and ethnic minorities

The global prevalence of diabetes for all age groups is estimated to be 2.8%. Type 2 diabetes accounts for at least 90% of diabetes worldwide. Diabetes incidence, prevalence, and disease progression varies by ethnic group. This review highlights unique aspects of the risk of developing diabetes, its overwhelming vascular complications, and their management mainly using data among South Asians and African-Caribbeans in the UK but also using non-UK data. It is concluded that although the origin of the ethnic differences in incidence need further clarification, many factors should be amenable to prevention and treatment in all ethnic groups worldwide.

Genetic interaction among three genomic regions creates distinct contributions to early- and late-onset type 1 diabetes mellitus

There are two peaks in the distribution of the age of onset of type 1 diabetes mellitus (T1DM)--the first in early childhood and the second at the time of puberty. Although T1DM results from the interaction of genetic and non-genetic factors, it has not been established which factors contribute to the bimodal distribution. The genetic component of T1DM is in large part related to genes from the human leukocyte antigen (HLA) complex (IDDM1); however, loci from the variable nucleotide tandem repeat (VNTR) region of the insulin (INS) gene (IDDM2) and more recently, the cytotoxic T-lymphocyte-associated protein-4 region (CTLA4, IDDM12) have also been implicated. Therefore, we examined the potential interaction between these loci through the influence of the age of onset of T1DM in diabetic and control Caucasian individuals. We discovered that younger individuals with HLA-DRB1*0301/DRB1*04 and INS I/I genotypes exhibited increased susceptibility to T1DM, whereas the interaction of INS I/I and CTLA4 G/G genotypes was more common in older children with T1DM. Combining the age of onset of T1DM with specific genotypes may operate to produce a single disease through different underlying causes.

Access to care for patients with insulin-requiring diabetes in developing countries: case studies of Mozambique and Zambia

OBJECTIVE

The objective of this study was to assess the barriers to care for patients with insulin-requiring diabetes in Mozambique and Zambia.

RESEARCH DESIGN AND METHODS

We used the Rapid Assessment Protocol for Insulin Access to collect information through interviews, discussions, site visits, and document reviews. Government organizations, health facilities, care givers, and patients were asked about care for people with insulin-requiring diabetes. Between 100 and 200 interviews/discussions per country were undertaken in and around the capital city and the regional capital and in a rural area.

RESULTS

Insulin was present in both countries in sufficient quantities, although the financial burden for health services and patients meant that problems with supply exist. There are problems with quantification of needs and equitable distribution of insulin. Problems with availability of syringes and testing equipment were noted, particularly in Mozambique. This lack of tools and infrastructure for diagnosis and follow-up coupled with low levels of health care worker training and lack of diagnostic reagents resulted in a substantial risk of misdiagnosis or failure to detect diabetes. The estimated prevalence of insulin-requiring diabetes differs more than 10-fold between urban and rural areas in Mozambique and 4-fold between Mozambique and Zambia, suggesting that problems in diagnosis and care result in substantial worsening of prognosis for such patients.

CONCLUSIONS

Insulin is necessary but not sufficient to improve prognosis for diabetic patients. A Rapid Assessment Protocol methodology can be used to define problems in health care delivery for diabetes. Proper care for insulin-requiring diabetes necessitates health systems able to provide trained personnel, medicines in sufficient quantity, and diagnostic and monitoring facilities.

The relationship between immune-mediated Type 1 diabetes mellitus and ethnicity

OBJECTIVE

To determine the proportion of adults with newly diagnosed Type 1 diabetes that had immune-mediated disease (IMD).

SUBJECTS AND METHODS

Two hundred fifteen patients with hyperglycemia and symptoms of insulin deficiency were screened for antibodies [islet cell antibodies (ICA), insulin autoantibodies (IAA), and glutamatic acid decarboxylase antibodies (GADA(65))] and HLA DR/DQ markers of IMD.

RESULTS

The mean age was 34 years and the mean BMI was 30.0 kg/m(2); 21.8% were non-Hispanic white (NHW), 27% were Latin American (LA), 47.9% were African American (AA), and 3.3% of other (OT) ethnic origins. Sixty individuals (28%) had one or more autoantibodies [Ab(+)]: 62% of NHW, 19% of AA, and 19% of LA. BMI was significantly lower (P<.01) in Ab(+). At least one HLA-DQ allele for susceptibility for IMD was identified in 52% of Ab(+).

CONCLUSIONS

These results suggest that islet cell autoantibodies and HLA markers of susceptibility for IMD are frequent in individuals of varying ethnic backgrounds, older age at onset, and higher body weight. Since early insulin therapy could delay what may otherwise be rapid progression to complete insulinopenia in patients with IMD, screening of adult diabetic patients for IMD at diagnosis may be of benefit to long-term management.

Incidence, prevalence, and mortality of insulin-dependent (type 1) diabetes mellitus in Lithuanian children during 1983-98

AIMS/HYPOTHESIS

Our purpose is to analyze interrelations of the incidence, prevalence and mortality of childhood-onset insulin-dependent diabetes mellitus (type 1) in Lithuania.

METHODS

Incidence and prevalence rates were based on the national type 1 diabetes register during 1983-98. The cohort study was performed to evaluate the standardized mortality ratios.

RESULTS

The average incidence of type 1 diabetes during the 16-yr study period was 7.36 per 100,000/yr. For both males and females the highest incidence of type 1 diabetes was recorded in the 10-14 yr age group. The regression-based linear trends of the increase in incidence in various age groups and the annual percentage change for both genders was 2.05 (p = 0.0039) and the greatest regression slope is observed for both genders in the 10-14 yr age group. Regression-based linear trends in type 1 diabetes prevalence indicate an even growth in all age groups (3.47; p = 0.001), although the annual percentage change is most prominent in the 5-9 yr age group for girls (4.95%/yr) and in the 10-14 yr age group for boys (4.06%/yr). The standardized mortality ratio of all-cause mortality in people with diabetes is higher than in the common population 7.71 (p < 0.0001). The standard mortality ratio for all causes increases with longer diabetes duration.

CONCLUSION/INTERPRETATION

The significant increasing trend of incidence and prevalence during 1983-98 is observed. The annual percentage change is similar. The young patients with type 1 diabetes have a higher mortality risk.

Childhood and adolescent diabetes mellitus in Arabs residing in the United Arab Emirates

In 9 years (1990-1998), 40 Arab patients between the ages of 0 and 18 years had newly diagnosed diabetes mellitus (DM) at the Al-Ain hospital, United Arab Emirates (UAE). In this cohort, 35 patients had Type 1 DM while the remaining five patients had features of early onset Type 2 DM. For Type 1 DM patients, the mean age at diagnosis of was 9.2+/-4.1 years. At presentation, their mean plasma glucose was 27.6+/-11/mmol with 28 (80%) patients having diabetic ketoacidosis (DKA), both being much higher than generally reported in the West. The mean insulin requirement increased from 0.84+/-0.27 U/kg per 24 h (0-9-year group) to 1.02+/-0.33 U/kg per 24 h (10-18-year group), P=0.055. The home glucose monitoring and the glycaemic control of these Type 1 DM patients were sub-optimal with 28% of patients having recurrence of DKA. Among the Type 2 DM patients, four (80%) were obese with a positive family history of Type 2 DM. All of them initially responded to diet and oral hypoglycaemic drugs. Public education about DM in childhood and prevention of adolescent obesity remain major public health challenges in the UAE.

Estimation of the prevalence of epilepsy in the Benin region of Zinvié using the capture-recapture method

BACKGROUND

The prevalence of epilepsy was estimated in two villages of 3134 inhabitants, in Benin, in April and May 1997 using the capture-recapture method.

METHODS

Information was obtained from (i) a door-to-door cross-sectional study, (ii) a non-medical source consisting of key informants (traditional practitioners, teachers, village leaders, and religious representatives) and (iii) a medical source through evaluation of medical records in health centres. In all the three situations, the diagnosis of epilepsy was confirmed by a neurologist.

RESULTS

The door-to-door survey found 50 epileptics, i.e. a prevalence of 15.9 per 1000. The non-medical source found 26 patients. The medical source found only four patients. In total, 66 epileptics were found by combining the three sources, giving a prevalence of 21.1 per 1000. After application of the capture-recapture method, the estimated number of cases from the door-to-door survey and non-medical source was 105, and 110 cases when the medical source was considered as well. The respective prevalences were 33.5 per 1000, and 35.1 per 1000.

CONCLUSIONS

The door-to-door survey has been usefully improved by using key informants. The epilepsy prevalence estimate found by capture-recapture is clearly higher than that found by traditional cross-sectional methods, and could better depict the frequency of epilepsy in Africa.

Seasonal variation in the incidence of Type 1 diabetes mellitus during 1983 to 1992 in the countries around the Baltic Sea

AIM

To examine seasonal patterns of incidence of Type 1 diabetes mellitus incidence in children aged 0-14 years in Finland, Sweden, Estonia, Latvia and Lithuania during 1983-1992 (1987-1992 for Finland).

METHODS

The study used a method that models incidence data using combinations of sine waves to model seasonal variation around a possible linear trend.

RESULTS

In Finland, a significant pattern was found for combined sexes and age groups 0-9 and 10-14 years. A significant pattern was also confirmed for 10-14 year-old boys. In Sweden, the best model with significant pattern was found separately for boys and girls and age groups 0-9 and 10-14 years, however, a significant pattern was confirmed for older girls only. A seasonal pattern in older boys in Finland and girls in Sweden was characterized by two cycles with decreased incidence in June and November-December. The pattern among younger children (0-9 or 5-9 years) had one cycle with a decreased incidence in May-June. In Estonia, a significant pattern was found for the age group 0-14 years and combined sexes. No significant seasonal patterns were found in Latvia and Lithuania.

CONCLUSIONS

The seasonal pattern with two cycles among older children and one cycle only among younger children may indicate different triggers of Type 1 diabetes mellitus for different age groups.

Migrant populations and the incidence of type 1 diabetes mellitus: an overview of the literature with a focus on the Spanish-heritage countries in Latin America

Type 1 diabetes mellitus (DM) is a 'chronic' autoimmune disorder leading to the destruction of the pancreatic beta cell. The natural history of diabetes includes a long subclinical (prediabetes) period. The pathogenesis is multifactorial and characterized by the interaction of environmental factors, with predisposing genes, most of which are associated with the HLA DR DQ loci. The relatively recent development of worldwide incidence registries for Type 1 DM has allowed us to compare the epidemiological results obtained in most parts of the world. This approach is particularly valuable in analysing the effects of migration of populations from one area of the world where the incidence of Type 1 DM is different (usually lower) to a new geographic setting. Properly designed migrant studies may be valuable in uncovering whether the genetic background remains more important than the new 'exposure' as illustrated by the Sardinian migration to Lazio and Lombardy. The presence of some putative 'protective' environmental exposures or the absence of those prevalent in the country of origin may explain the usually lower Type 1 DM incidence observed in most countries (Chile, Peru, Mexico) sharing a 'Spanish caucasoid genetic pool', and even in relatively genetically homogeneous groups such as Japanese populations migrating to Hawaii. In fact, the disease is caused by both genetic and environmental factors and to convince the scientific community of this fact is a primary responsibility for epidemiologists.

Incidence of insulin-dependent diabetes mellitus in Jordanian children aged 0-14 y during 1992-1996

An attempt was made by the Jordanian National Center for Diabetes, Endocrine and Genetic Diseases (NCDEGD) to identify all cases of type 1 diabetes among Jordanian children aged 0-14 y. Data were obtained retrospectively for the years 1992-1994 and prospectively for the years 1995 and 1996, including full name, national identifying number, date of birth, date of diagnosis and family history. The incidence was calculated as the number of cases per 100,000 population, according to the national census of 1994. The incidence rate for these years (1992 through 1996) was 2.8, 2.9, 3.2, 3.6 and 3.6 per 100,000 population, respectively. The male:female ratio was (1:1.03). Seasonal variation at clinical onset was noticed, with maximum incidence in the winter months and minimum incidence in the summer months. In conclusion, the incidence of type 1 diabetes mellitus in Jordanian children aged 0-14 y is among the lowest in the region, but is rising.

Long-term patterns in seasonality of insulin-dependent diabetes mellitus diagnosis in Austrian children

The analysis of the seasonal pattern of incidence of childhood insulin-dependent diabetes mellitus in Austria was carried out among cases where the child was under the age of 15 when diagnosed between 1979 and 1993. The cases are registered in the nationwide population-based Austrian insulin-dependent diabetes mellitus registry. Seasonal variation was compared between boys and girls and between three 5-year age groups. We also tested whether the seasonal pattern changed over the 15-year observation period. We found a significant seasonal variation among boys aged 10-14 and girls aged 5-14, while in the 0-4 years age group no seasonal pattern could be demonstrated. Two peaks in incidence were identified during a calendar year (February-March and September-October) for girls aged 5-14. For boys aged 10-14, a yearly cycle was found with a peak in January and October. An extension of the Poisson regression model for testing seasonality by Jones et al. was developed to allow for estimation of a time-dependent amplitude of the seasonal component. The annual incidence rate increased by 36% during the observation period, but no significant change in seasonal pattern could be demonstrated.

Incidence of insulin-dependent diabetes (IDDM) and non-insulin-dependent diabetes (NIDDM) (0-34 years at onset) in Benghazi, Libya

The incidence of insulin-dependent diabetes (IDDM) and non-insulin-dependent diabetes (NIDDM) in Benghazi, Libya in the < 35-year age group during the period 1981-1990 are reported. Incidence data for IDDM were based on prospective registration of patients while incidence data for NIDDM were based on analysis of files. Case ascertainment of IDDM cases was estimated to be > 95%. Incidence of total diabetes (IDDM and NIDDM) (per 100000 population) was significantly higher in females (43.8; 95% confidence Interval (CI) 40.6-47.2) than in males (28.9, 26.6-31.3) (P < 0.001). The overall incidence rates of IDDM and NIDDM were 9.0 (CI, 8.1-10.0) and 27.3 (CI, 25.4-28.2), respectively. Rates of IDDM were 9.4 (CI, 8.1-10.9) among males and 8.5 (CI, 7.3-10.0) among females. Rates of NIDDM were 19.6 (CI, 18.1-22.2) among males and 35.3 (CI, 32.4-37.8) among females. IDDM patients showed a female predominance in the 0- to 14-year age range (P > 0.05) and a male predominance in the 15- to 34-year age range (P > 0.05). NIDDM showed equal incidence in males and females in the 0- to 14-year age range and twofold higher incidence in females than in males in the 15- to 34-year age group (P < 0.001). Yearly variation and seasonality of onset were not significant in IDDM cases (P > 0.05). Fifty-six percent of NIDDM cases were obese compared to only 6% of IDDM cases. The study revealed that diabetes mellitus is a common chronic disease in children and young Libyan Arabs. It has shown that NIDDM in Benghazi is twofold higher in females than in males in the 15- to 34-year age group. It has also shown that age per se is not a reliable criterion for the classification of diabetes into IDDM and NIDDM.

Insulin-dependent diabetes mellitus in southern Chinese children: an overview

Thirty-three southern Chinese children with insulin-dependent diabetes mellitus (IDDM) were studied. The patients had a mean follow-up of 5.2 years (range 1.2-8.2). The mean age of onset was 8.3 years (range 1.7-13.5). The mean duration of symptoms before diagnosis was 22 days. Ten patients (30%) presented with diabetic ketoacidosis at diagnosis. Only one patient (3%) was found to have thyroid microsomal antibodies and none was found to have hypothyroidism or hyperthyroidism. Incidence and prevalence were calculated from data recorded retrospectively and prospectively in a population-based registry of IDDM. The prevalence in 1991 and 1992 was 8.3 per 100,000 children under 15 years of age. The age-standardized incidence of IDDM was 1.7/100,000 per year with the 95% confidence interval of 1.2-2.4/100,000 per year for children under 15 years of age during the years 1986-93. The incidence for males was 1.1/100,000 per year and for females, 2.4/100,000 per year.

A review of the recent epidemiological data on the worldwide incidence of type 1 (insulin-dependent) diabetes mellitus. World Health Organization DIAMOND Project Group

Nearly 70 registries from more than 40 countries have collected and published incidence data of childhood Type 1 (insulin-dependent) diabetes mellitus up to the end of the 1980s. The majority of incidence data comes from regions of high incidence i.e. from Europe and North America. All these published data facilitate the descriptive comparison of incidence and variation of the occurrence of Type 1 diabetes roughly throughout the northern hemisphere. The aim of this paper is to review and compare the most recent epidemiology data on the incidence of Type 1 diabetes among children under the age of 15 years. A clear difference in incidence appeared between northern and southern hemisphere with no countries below the equator having an incidence greater than 15.0 per 100,000. In contrast above the equator the disease is common. Between continents the variation in incidence showed that the lowest incidences were found in Asia, followed by Oceania (Australia and New Zealand), South and North America, and the highest rates were in Europe. The incidence varied from 0.6 per 100,000 in Korea and Mexico to 35.3 per 100,000 in Finland showing prominent worldwide variation in incidence of Type 1 diabetes. The largest intracontinental variation in incidence appeared in Europe, varying from the highest in Finland to the lowest (4.6 per 100,000) in northern Greece. The highest incidence in the world was in northern Europe, but within the continent scale there were some striking exceptions from the overall level of incidence.(ABSTRACT TRUNCATED AT 250 WORDS)