Projections of type 1 and type 2 diabetes burden in the U.S. population aged <20 years through 2050: dynamic modeling of incidence, mortality, and population growth

The future of treating youth-onset type 2 diabetes: focusing upstream and extending our influence into community environments

Type 2 diabetes (T2D) in youth is on the rise and many of these youth already have comorbidity at disease onset. The TODAY trial clearly demonstrated the challenges of treating this disease. Obesity is a key risk factor in the development of youth-onset T2D, and its prevention can mitigate the risk for developing T2D. However, childhood obesity prevention efforts to date have shown only modest effectiveness. Considering the larger, complex socioeconomic and cultural contexts that influence health behaviors among children and their families can enhance prevention efforts. Community-based participatory, multi-component, multi-setting childhood obesity prevention initiatives designed using the socio-ecological model and systems theory have been effective in sustainably decreasing childhood overweight and obesity. To advance our progress in treating and preventing T2D in youth, we must apply this new knowledge on community-wide childhood obesity prevention to enhance the impact of individual-level therapeutic strategies such as the TODAY intervention.

Complications and comorbidities of T2DM in adolescents: findings from the TODAY clinical trial

With the rise in childhood obesity, type 2 diabetes mellitus (T2DM) has been recognized to occur in adolescents with increasing frequency. Although much is known about T2DM in adults, few studies have examined the treatment and complications of T2DM in youth. The Treatment Options for type 2 Diabetes in Adolescents and Youth (TODAY) study was designed to evaluate the efficacy of various treatments and provided a unique opportunity to study the disease progression and appearance of complications in a pediatric cohort with recent onset of the disease. In the TODAY study, hypertension was present in 11.6% of the population at baseline and increased to 33.8% by the end of the study. Prevalence of high-risk LDL-cholesterol rose from 4.5% at baseline to 10.7% at the end of the study. Microalbuminuria was found in 6.3% of the cohort at baseline and increased to 16.6%. Retinopathy was not assessed upon entry into TODAY, but was present in 13.9% of the TODAY cohort at the end of the study. Experience to date indicates that these complications and comorbidities are similar to those seen in adults, but occur on an accelerated timeline. The early manifestation of diabetes complications in youth-onset T2DM suggests that this group will be burdened with the tangible consequences of cardiovascular disease, nephropathy, and retinopathy in the third and fourth decades of life. It is hoped that through an early, aggressive approach to treatment and prevention, we may be able to curb the onset and progression of these potentially devastating outcomes.

Human adipose-derived stromal/stem cells protect against STZ-induced hyperglycemia: analysis of hASC-derived paracrine effectors

Adipose-derived stromal/stem cells (ASCs) ameliorate hyperglycemia in rodent models of islet transplantation and autoimmune diabetes, yet the precise human ASC (hASC)-derived factors responsible for these effects remain largely unexplored. Here, we show that systemic administration of hASCs improved glucose tolerance, preserved β cell mass, and increased β cell proliferation in streptozotocin-treated nonobese diabetic/severe combined immunodeficient mice. Coculture experiments combining mouse or human islets with hASCs demonstrated that islet viability and function were improved by hASCs following prolonged culture or treatment with proinflammatory cytokines. Analysis of hASC-derived factors revealed vascular endothelial growth factor and tissue inhibitor of metalloproteinase 1 (TIMP-1) to be highly abundant factors secreted by hASCs. Notably, TIMP-1 secretion increased in the presence of islet stress from cytokine treatment, while TIMP-1 blockade was able to abrogate in vitro prosurvival effects of hASCs. Following systemic administration by tail vein injection, hASCs were detected in the pancreas and human TIMP-1 was increased in the serum of injected mice, while recombinant TIMP-1 increased viability in INS-1 cells treated with interleukin-1beta, interferon-gamma, and tumor necrosis factor alpha. In aggregate, our data support a model whereby factors secreted by hASCs, such as TIMP-1, are able to mitigate against β cell death in rodent and in vitro models of type 1 diabetes through a combination of local paracrine as well as systemic effects.

Trends in pre-pregnancy diabetes among deliveries in 19 U.S. states, 2000-2010

BACKGROUND

Trends in state-level prevalence of pre-pregnancy diabetes mellitus (PDM; i.e., type 1 or type 2 diabetes diagnosed before pregnancy) among delivery hospitalizations are needed to inform healthcare delivery planning and prevention programs.

PURPOSE

To examine PDM trends overall, by age group, race/ethnicity, primary payer, and with comorbidities such as pre-eclampsia and pre-pregnancy hypertension, and to report changes in prevalence over 11 years.

METHODS

In 2014, State Inpatient Databases from the Agency for Healthcare Research and Quality were analyzed to identify deliveries with PDM and comorbidities using diagnosis-related group codes and ICD-9-CM codes. General linear regression with a log-link and binomial distribution was used to assess the annual change.

RESULTS

Between 2000 and 2010, PDM deliveries increased significantly in all age groups, all race/ethnicity groups, and in all states examined (p<0.01). The age-standardized prevalence of PDM increased from 0.65 per 100 deliveries in 2000 to 0.89 per 100 deliveries in 2010, with a relative change of 37% (p<0.01). Although PDM rates were highest in the South, some of the largest relative increases occurred in five Western states (≥69%). Non-Hispanic blacks had the highest PDM rates and the highest absolute increase (0.26 per 100 deliveries). From 2000 to 2010, the proportion of PDM deliveries with pre-pregnancy hypertension increased significantly (p<0.01) from 7.4% to 14.1%.

CONCLUSIONS

PDM deliveries are increasing overall and particularly among those with PDM who have hypertension. Effective diabetes prevention and control strategies for women of childbearing age may help protect their health and that of their newborns.

Diabetes and congenital heart defects: a systematic review, meta-analysis, and modeling project

CONTEXT

Maternal pregestational diabetes (PGDM) is a risk factor for development of congenital heart defects (CHDs). Glycemic control before pregnancy reduces the risk of CHDs. A meta-analysis was used to estimate summary ORs and mathematical modeling was used to estimate population attributable fractions (PAFs) and the annual number of CHDs in the U.S. potentially preventable by establishing glycemic control before pregnancy.

EVIDENCE ACQUISITION

A systematic search of the literature through December 2012 was conducted in 2012 and 2013. Case-control or cohort studies were included. Data were abstracted from 12 studies for a meta-analysis of all CHDs.

EVIDENCE SYNTHESIS

Summary estimates of the association between PGDM and CHDs and 95% credible intervals (95% CrIs) were developed using Bayesian random-effects meta-analyses for all CHDs and specific CHD subtypes. Posterior estimates of this association were combined with estimates of CHD prevalence to produce estimates of PAFs and annual prevented cases. Ninety-five percent uncertainty intervals (95% UIs) for estimates of the annual number of preventable cases were developed using Monte Carlo simulation. Analyses were conducted in 2013. The summary OR estimate for the association between PGDM and CHDs was 3.8 (95% CrI=3.0, 4.9). Approximately 2670 (95% UI=1795, 3795) cases of CHDs could potentially be prevented annually if all women in the U.S. with PGDM achieved glycemic control before pregnancy.

CONCLUSIONS

Estimates from this analysis suggest that preconception care of women with PGDM could have a measureable impact by reducing the number of infants born with CHDs.

Has the gap between pancreas and islet transplantation closed?

Both pancreas and islet transplantations are therapeutic options for complicated type 1 diabetes. Until recent years, outcomes of islet transplantation have been significantly inferior to those of whole pancreas. Islet transplantation is primarily performed alone in patients with severe hypoglycemia, and recent registry reports have suggested that results of islet transplantation alone in this indication may be about to match those of pancreas transplant alone in insulin independence. Figures of 50% insulin independence at 5 years for either procedure have been cited. In this article, we address the question whether islet transplantation has indeed bridged the gap with whole pancreas. Looking at the evidence to answer this question, we propose that although pancreas may still be more efficient in taking recipients off insulin than islets, there are in fact numerous "gaps" separating both procedures that must be taken into the equation. These "gaps" relate to organ utilization, organ allocation, indication for transplantation, and morbidity. In-depth analysis reveals that islet transplantation, in fact, has an edge on whole pancreas in some of these aspects. Accordingly, attempts should be made to bridge these gaps from both sides to achieve the same level of success with either procedure. More realistically, it is likely that some of these gaps will remain and that both procedures will coexist and complement each other, to ensure that β cell replacement can be successfully implemented in the greatest possible number of patients with type 1 diabetes.

The development of next-generation screening and diagnostic platforms will change diabetes care

Diabetes mellitus is a common disease with a rising incidence and the findings of hyperglycemia and glucosuria. However, there are multiple types of diabetes, each with distinct etiologies. The two major types of diabetes are type 1, which is caused by an autoimmune process, and type 2, which is thought to be primarily metabolic, resulting from insulin resistance, often in the setting of obesity. Historically, the distinction between these two types was obvious. Here, we discuss how this paradigm has dramatically changed because of both the evolving epidemiology of diabetes mellitus and new and emerging tools, and therapies to diagnose and treat diabetes. As we believe that understanding these changes is critical to providing optimal care to patients with diabetes, we have developed a novel plasmonic gold chip platform that is able to meet the new and emerging demands of modern diabetes care.

Islet-after-failed-pancreas and pancreas-after-failed islet transplantation: Two complementary rescue strategies to control diabetes

For selected patients with type 1 diabetes, β-cell replacement is the treatment of choice, either by islet transplantation (ITX) or whole pancreas transplantation (PTX). When either modality fails, current practice is to consider retransplantation, or return to exogenous insulin. We investigate outcomes with PTX after failed ITX (PAI), and ITX after failed PTX (IAP). All patients receiving PAI or IAP at a single institution were identified. Donor and recipient variables were documented, including transplant outcomes analyzed for insulin requirement and metabolic control. Five subjects were listed for PAI, and 2 received transplants. Of the 4 listed for IAP, 3 have received transplants. The mean waitlist time was 4.5 ± 4.1 y for PAI and 0.35 ±0 .4 y for IAP (p = 0.08). Metabolic control was excellent after PAI, with 2/2 insulin-independent. After IAP, 1/2 achieved insulin independence and good metabolic control after 2 islet infusions. The third could not receive 2(nd) infusion and presented c-peptide levels < 0.1 nmol/L. Both strategies are feasible. The outcomes after PAI in our center must be offset by much longer waitlist time due to the sensitization status of these patients. Data from multicentre experience will allow more robust comparative outcomes to be made, the current observations being restricted to a limited patient set.

Morbidity and mortality in young-onset type 2 diabetes in comparison to type 1 diabetes: where are we now?

Increasingly, we recognise that type 2 diabetes in youth is a disease with an aggressive time course and a significant complication risk. On the other hand, outcomes for youth with type 1 diabetes appear generally to be improving. With increasing numbers of both types of diabetes in youth, it is timely that a comparative perspective is offered to help clinicians prognosticate more appropriately. Contemporary comparative studies add a new perspective to a consistent story, that for youth-onset type 2 diabetes, the development and progression of cardio-renal complications are increased and the survival prognosis is significantly worse than for type 1 diabetes. Here, we review this mounting evidence, highlight the importance of metabolic syndrome factors in the excess risk and underscore that there remains a significant mortality gap for youth with either type of diabetes, to be addressed as a matter of urgency.

Diabetic kidney disease in children and adolescents

Diabetes, more frequently type 1, but increasingly also type 2, commonly occurs in childhood. While more advanced diabetic kidney disease (DKD), e.g., loss of glomerular filtration rate (GFR), does not occur until adulthood, kidney biopsies show DKD structural changes as early as 1.5-5 years after the onset of type 1 diabetes. Earliest clinical sign of DKD, increased urine albumin excretion, commonly appears during childhood and adolescence and presents an important opportunity to detect and intervene in early DKD, perhaps more successfully than later in the disease course. Longitudinal studies of type 1 diabetes have enriched our understanding of the DKD natural history and modifiable risk factors for DKD progression. These studies have also shown that the presence of DKD marks a subset of people with diabetes who are at the highest risk of early mortality, supporting an enhanced focus on DKD detection, prevention, and treatment. Early studies suggest that youth-onset type 2 diabetes is associated with a higher prevalence of comorbidities and risk factors and follows a more aggressive natural history. A deeper understanding of the natural history, risk factors, underlying mechanisms and therapeutic options for DKD in young-onset type 2 diabetes awaits further studies.

Nonalcoholic steatohepatitis and insulin resistance in children

Various pathological conditions can cause fatty liver in children. Nonalcoholic steatohepatitis (NASH) in children has been known since 1983. However, NASH diagnosed in childhood does not have a favorable outcome. The pathological characteristics of NASH are significantly different between children and adults. Nonalcoholic fatty liver disease (NAFLD)/NASH is accompanied by insulin resistance, which plays a pivotal role in its pathophysiology in both children and adults. In NASH, a “two-hit” model involving triglyceride accumulation (first hit) and liver damage (second hit) has been accepted. Insulin resistance was found to correlate with changes in fat levels; however, it did not correlate with fibrosis or NAFLD activity score in children. Therefore, insulin resistance may be important in the first hit. Because there is obvious familial clustering in NASH, genetic predisposition as well as environmental factors including diet might be the second hit of NAFLD/NASH.

Use of administrative and electronic health record data for development of automated algorithms for childhood diabetes case ascertainment and type classification: the SEARCH for Diabetes in Youth Study

BACKGROUND

The performance of automated algorithms for childhood diabetes case ascertainment and type classification may differ by demographic characteristics.

OBJECTIVE

This study evaluated the potential of administrative and electronic health record (EHR) data from a large academic care delivery system to conduct diabetes case ascertainment in youth according to type, age, and race/ethnicity.

SUBJECTS

Of 57 767 children aged <20 yr as of 31 December 2011 seen at University of North Carolina Health Care System in 2011 were included.

METHODS

Using an initial algorithm including billing data, patient problem lists, laboratory test results, and diabetes related medications between 1 July 2008 and 31 December 2011, presumptive cases were identified and validated by chart review. More refined algorithms were evaluated by type (type 1 vs. type 2), age (<10 vs. ≥10 yr) and race/ethnicity (non-Hispanic White vs. 'other'). Sensitivity, specificity, and positive predictive value were calculated and compared.

RESULTS

The best algorithm for ascertainment of overall diabetes cases was billing data. The best type 1 algorithm was the ratio of the number of type 1 billing codes to the sum of type 1 and type 2 billing codes ≥0.5. A useful algorithm to ascertain youth with type 2 diabetes with 'other' race/ethnicity was identified. Considerable age and racial/ethnic differences were present in type-non-specific and type 2 algorithms.

CONCLUSIONS

Administrative and EHR data may be used to identify cases of childhood diabetes (any type), and to identify type 1 cases. The performance of type 2 case ascertainment algorithms differed substantially by race/ethnicity.

The SEARCH for Diabetes in Youth study: rationale, findings, and future directions

The SEARCH for Diabetes in Youth (SEARCH) study was initiated in 2000, with funding from the Centers for Disease Control and Prevention and support from the National Institute of Diabetes and Digestive and Kidney Diseases, to address major knowledge gaps in the understanding of childhood diabetes. SEARCH is being conducted at five sites across the U.S. and represents the largest, most diverse study of diabetes among U.S. youth. An active registry of youth diagnosed with diabetes at age <20 years allows the assessment of prevalence (in 2001 and 2009), annual incidence (since 2002), and trends by age, race/ethnicity, sex, and diabetes type. Prevalence increased significantly from 2001 to 2009 for both type 1 and type 2 diabetes in most age, sex, and race/ethnic groups. SEARCH has also established a longitudinal cohort to assess the natural history and risk factors for acute and chronic diabetes-related complications as well as the quality of care and quality of life of persons with diabetes from diagnosis into young adulthood. Many youth with diabetes, particularly those from low-resourced racial/ethnic minority populations, are not meeting recommended guidelines for diabetes care. Markers of micro- and macrovascular complications are evident in youth with either diabetes type, highlighting the seriousness of diabetes in this contemporary cohort. This review summarizes the study methods, describes key registry and cohort findings and their clinical and public health implications, and discusses future directions.

Blood spot-based measures of glucose homeostasis and diabetes prevalence in a nationally representative population of young US adults

PURPOSE

We investigated understudied biomarker-based diabetes among young US adults, traditionally characterized by low cardiovascular disease risk.

METHODS

We examined 15,701 participants aged 24 to 32 years at Wave IV of the National Longitudinal Study of Adolescent Health (Add Health, 2008). The study used innovative and relatively noninvasive methods to collect capillary whole blood via finger prick at in-home examinations in all 50 states.

RESULTS

Assays of dried blood spots produced reliable and accurate values of HbA1c. Reliability was lower for fasting glucose and lowest for random glucose. Mean (SD) HbA1c was 5.6% (0.8%). More than a quarter (27.4%) had HbA1c-defined prediabetes. HbA1c was highest in the black, non-Hispanic race/ethnic group, inversely associated with education, and more common among the overweight/obese and physically inactive. The prevalence of diabetes defined by previous diagnosis or use of antidiabetic medication was 2.9%. Further incorporating HbA1c and glucose values, the prevalence increased to 6.8%, and among these participants, 38.9% had a previous diagnosis of diabetes (i.e., aware). Among those aware, 37.6% were treated and 64.0% were controlled (i.e., HbA1c < 7%).

CONCLUSIONS

A contemporary cohort of young adults faces a historically high risk of diabetes but there is ample opportunity for early detection and intervention.

Lifestyle interventions to reduce diabetes and cardiovascular disease risk among children

Diseases once associated with older adulthood, type 2 diabetes and cardiovascular disease, are increasingly diagnosed in children and adolescents. Interventions designed to assist adults in modifying dietary and physical activity habits have been shown to help prevent the development of type 2 diabetes and cardiovascular disease in adults. Given the unfortunate rise in both of these diseases in pediatric populations, it is increasingly important to begin prevention efforts in childhood or prenatally. There is strong empirical support for utilizing lifestyle interventions to prevent these diseases in adults; it is not clear whether the same holds true for pediatric populations. The present review examines lifestyle management efforts to prevent type 2 diabetes and cardiovascular disease in children across socioecological levels. Recommendations are made for expanding the traditional focus of lifestyle interventions from dietary and physical activity behaviors to target additional risks for these diseases such as smoking and depression in youth.

Are patients with diabetes mellitus satisfied with technologies used to assist with diabetes management and coping?: A structured review

Modern technological devices supporting coping and management for patients with diabetes are increasingly popular and could be important healthcare tools. This review aimed to evaluate patient satisfaction and perceptions regarding these devices, examples of which include short message service reminder systems, online educational programs, and clinician-patient electronic communication. Therapy devices such as continuous glucose monitors and continuous subcutaneous insulin infusion pumps are not included in this review. Embase, Psychinfo, Medline, CINAHL, and gray literature databases were searched for "diabetes mellitus," "technical device," "patient satisfaction," and their synonyms. This review was carried out according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement guidelines. The search produced 1,902 studies, 26 of which were included in the review: type 1 diabetes mellitus (eight studies), type 2 diabetes mellitus (nine studies), and both (nine studies). High satisfaction was seen with almost all devices and correlated strongly with ease of use and improved diabetes management. Satisfaction was not affected by participant age, and the effect of diabetes type was not assessed. Web devices were reported as easiest to use. Increased support was valued and resulted from devices facilitating interaction with healthcare professionals (HCPs) or peers. Technical difficulties were barriers to both use and satisfaction. Overall, patients enjoyed supplementing their usual therapy with these devices. Perceived support from HCPs or peers formed an important aspect of patient satisfaction and should be considered for future interventions.

College health service capacity to support youth with chronic medical conditions

BACKGROUND AND OBJECTIVE

Twenty percent of US youth have a chronic medical condition and many attend college. Guidelines for transition from pediatric to adult care do not address college health services, and little is known about their capacity to identify, support, and provide care for these youth. The objective of this study was to describe college health center policies, practices, and resources for youth with chronic medical conditions (YCMC).

METHODS

Survey of medical directors from health centers of a representative sample of 200 4-year US colleges with ≥ 400 enrolled undergraduate students. Patterns of identification, management, and support for youth with a general chronic medical condition and with asthma, diabetes, and depression, were investigated; χ(2) and Fisher exact tests were used to ascertain differences by institutional demographics.

RESULTS

Directors at 153 institutions completed the survey (76.5% response rate). Overall, 42% of schools had no system to identify YCMC. However, almost a third (31%) did identify and add to a registry of incoming YCMC on review of medical history, more likely in private (P < .001) and small (<5000 students, P = .002) colleges; 24% of health centers contacted YCMC to check-in/make initial appointments. Most institutions could manage asthma and depression (83% and 69%, respectively); 51% could manage diabetes on campus.

CONCLUSIONS

Relatively few US colleges have health systems to identify and contact YCMC, although many centers have capacity to provide primary care and management of some conditions. Guidelines for transition should address policy and practices for pediatricians and colleges to enhance comanagement of affected youth.

Care delivery in youth with type 2 diabetes - are we meeting clinical practice guidelines?

BACKGROUND

Studies indicate high rates of treatment failure and early onset diabetes-related complications in youth-onset type 2 diabetes (T2D). We aim to describe the quality of care provided to children and youth with T2D.

METHODS

This prospective cohort study used administrative datasets to describe individuals aged 10-24 yr diagnosed with T2D at <20 yr of age (488 individuals; 2111 person-years). The primary outcome was being 'at goal' for adherence to Canadian clinical practice guidelines (CPGs). This was defined as having either optimal [three diabetes-related physician visits/year, three hemoglobin A1C (A1C) tests/year, and all recommended screening tests for complications (i.e., retinopathy, nephropathy)] or good (two diabetes-related physician visits/year, two A1C tests/year, and at least two screening tests) adherence to CPGs. Descriptive statistics and logistic regression modeling were used.

RESULTS

Sixty eight percentage person-years had poor adherence to CPGs (<2 physician visits and A1c tests/year and no screening tests). Only 29% and 25% were at goal for adherence in the 15-19 and 20-24 yr age groups, respectively. There was a 52% decreased odds of being at goal for adherence 4 yr after diagnosis of T2D (p < 0.001). For every year increase in age at diagnosis, there was a 5% decreased odds of being at goal (p = 0.04).

CONCLUSIONS

Youth with T2D are not receiving high quality care, and older youth and young adults are particularly at risk. Future research is needed to understand the effectiveness of care in the context of poor adherence as well as patient, physician, and health system factors that might improve adherence.

Trends in lifetime risk and years of life lost due to diabetes in the USA, 1985-2011: a modelling study

BACKGROUND

Diabetes incidence has increased and mortality has decreased greatly in the USA, potentially leading to substantial changes in the lifetime risk of diabetes. We aimed to provide updated estimates for the lifetime risk of development of diabetes and to assess the effect of changes in incidence and mortality on lifetime risk and life-years lost to diabetes in the USA.

METHODS

We incorporated data about diabetes incidence from the National Health Interview Survey, and linked data about mortality from 1985 to 2011 for 598 216 adults, into a Markov chain model to estimate remaining lifetime diabetes risk, years spent with and without diagnosed diabetes, and life-years lost due to diabetes in three cohorts: 1985-89, 1990-99, and 2000-11. Diabetes was determined by self-report and was classified as any diabetes, excluding gestational diabetes. We used logistic regression to estimate the incidence of diabetes and Poisson regression to estimate mortality.

FINDINGS

On the basis of 2000-11 data, lifetime risk of diagnosed diabetes from age 20 years was 40·2% (95% CI 39·2-41·3) for men and 39·6% (38·6-40·5) for women, representing increases of 20 percentage points and 13 percentage points, respectively, since 1985-89. The highest lifetime risks were in Hispanic men and women, and non-Hispanic black women, for whom lifetime risk now exceeds 50%. The number of life-years lost to diabetes when diagnosed at age 40 years decreased from 7·7 years (95% CI 6·5-9·0) in 1990-99 to 5·8 years (4·6-7·1) in 2000-11 in men, and from 8·7 years (8·4-8·9) to 6·8 years (6·7-7·0) in women over the same period. Because of the increasing diabetes prevalence, the average number of years lost due to diabetes for the population as a whole increased by 46% in men and 44% in women. Years spent with diabetes increased by 156% in men and 70% in women.

INTERPRETATION

Continued increases in the incidence of diagnosed diabetes combined with declining mortality have led to an acceleration of lifetime risk and more years spent with diabetes, but fewer years lost to the disease for the average individual with diabetes. These findings mean that there will be a continued need for health services and extensive costs to manage the disease, and emphasise the need for effective interventions to reduce incidence.

FUNDING

None.

Update on the American Diabetes Association Standards of Medical Care

The diagnosis and management of diabetes in primary care has increased immensely over the past several years. The focus of this article is on the latest substantive revisions in the diagnosis, treatment, and management of diabetes, which was presented in the January 2014 issue of the ADA's journal Diabetes Care.

Systematic review of various laser intervention strategies for proliferative diabetic retinopathy

Diabetic retinopathy (DR) is a common complication of diabetes. DR obstructs blood supply to the retina and has serious and long-lasting detrimental effects on quality of life. Panretinal photocoagulation, a laser surgical intervention, is advocated for early treatment of DR to prevent visual loss; however, results from studies reporting its efficacy vary markedly. In this review, we systematically conducted a database search of randomized controlled trials that investigated the safety and efficacy of different types of laser interventions, alone or in combination with adjunct intravitreal steroid utilization, in patients with DR. Data from 14 studies demonstrated that panretinal photocoagulation can be a safe and effective option for reducing visual loss and blindness in patients with DR.

Targeted immune interventions for type 1 diabetes: not as easy as it looks!

PURPOSE OF REVIEW

Although insulin is lifesaving and sustaining for those with type 1 diabetes (T1D), curing the disease will be much more complex than simple replacement of this hormone. T1D is an autoimmune disease orchestrated by T cells, and includes many arms of the immune response. Tremendous effort has gone into understanding its underlying immune, genetic, and environmental causes, and this progress has led to immunologically based clinical trials in T1D. This review will focus primarily on the clinical trials of the past decade that have attempted to translate these fundamental findings.

RECENT FINDINGS

It is known that powerful, nonspecific immune suppressants can temporarily slow the course of newly diagnosed T1D, yet are too toxic for long-term use, especially in children. Recent clinical trials to reverse T1D have used newly developed therapies that target specific components of the immune process believed to be involved with T1D. Although well justified and designed, no recent approach has resulted in clinical remission and few have had any effect on disease course.

SUMMARY

Advances in our fundamental understanding of how the human diabetes immune response is activated and regulated coupled with lessons that have been learnt from the most recent era of completed trials are guiding us toward the development of more effective, multipronged therapies to ablate diabetes autoimmunity, restore immune tolerance, preserve β cells, and, ultimately, improve the lives of patients with T1D.

Contrasting the clinical care and outcomes of 2,622 children with type 1 diabetes less than 6 years of age in the United States T1D Exchange and German/Austrian DPV registries

AIMS/HYPOTHESIS

The study aimed to compare participant characteristics, treatment modalities and clinical outcomes in registry participants less than 6 years old.

METHODS

Participant characteristics, treatment modalities and clinical outcomes (HbA1c, severe hypoglycaemia [SH] and diabetic ketoacidosis [DKA]) as well as frequencies of attaining HbA1c goals in line with the International Society for Pediatric and Adolescent Diabetes (<7.5% [<58 mmol/mol]) and ADA (<8.5% [<69 mmol/mol]) were compared.

RESULTS

Insulin pump use was more frequent (74% vs 50%, p < 0.001) and HbA1c levels lower in the Prospective Diabetes Follow-up Registry (DPV) than in the T1D Exchange (T1DX) (mean 7.4% vs 8.2%, p < 0.001). A lower HbA1c level was seen in the DPV compared with the T1DX for both pump users (p < 0.001) and injection users (p < 0.001). More children from DPV were meeting the recommended HbA1c goals, compared with children from T1DX (HbA1c <7.5%: 56% vs 22%, p < 0.001; HbA1c <8.5%: 90% vs 66%, p < 0.001). The adjusted odds of having an HbA1c level <7.5% or <8.5% were 4.2 (p < 0.001) and 3.6 (p < 0.001) higher for the DPV than the T1DX, respectively. The frequency of SH did not differ between registries or by HbA1c, whereas the frequency of DKA was higher for the T1DX and greater in those with higher HbA1c levels.

CONCLUSIONS/INTERPRETATION

DPV data indicate that an HbA1c of <7.5% can frequently be achieved in children with type 1 diabetes who are under 6 years old. An improved metabolic control of type 1 diabetes in young patients appears to decrease the risk of DKA without increasing SH. The greater frequency of suboptimal control in young patients in the T1DX compared with the DPV is not fully explained by a less frequent use of insulin pumps and may relate to the higher HbA1c targets that are recommended for this age group in the USA.

A plasmonic chip for biomarker discovery and diagnosis of type 1 diabetes

Type 1 diabetes (T1D) is an autoimmune disease, whereas type 2 diabetes (T2D) results from insulin resistance and beta cell dysfunction. Previously, the onset of these two separate diseases was easily distinguished, with children being most at risk for T1D and T2D occurring in overweight adults. However, the dramatic rise in obesity, coupled with the notable increase in T1D, has created a large overlap in these previously discrete patient populations. Delayed diagnosis of T1D can result in severe illness or death, and rapid diagnosis of T1D is critical for the efficacy of emerging therapies. However, attempts to apply next-generation platforms have been unsuccessful for detecting diabetes biomarkers. Here we describe the development of a plasmonic gold chip for near-infrared fluorescence-enhanced (NIR-FE) detection of islet cell-targeting autoantibodies. We demonstrate that this platform has high sensitivity and specificity for the diagnosis of T1D and can be used to discover previously unknown biomarkers of T1D.

Environmental endocrine disruption of energy metabolism and cardiovascular risk

Rates of metabolic diseases have increased at an astounding rate in recent decades. Even though poor diet and physical inactivity are central drivers, these lifestyle changes alone fail to fully account for the magnitude and rapidity of the epidemic. Thus, attention has turned to identifying novel risk factors, including the contribution of environmental endocrine disrupting chemicals. Epidemiologic and preclinical data support a role for various contaminants in the pathogenesis of diabetes. In addition to the vascular risk associated with dysglycemia, emerging evidence implicates multiple pollutants in the pathogenesis of atherosclerosis and cardiovascular disease. Reviewed herein are studies linking endocrine disruptors to these key diseases that drive significant individual and societal morbidity and mortality. Identifying chemicals associated with metabolic and cardiovascular disease as well as their mechanisms of action is critical for developing novel treatment strategies and public policy to mitigate the impact of these diseases on human health.

Prevalence of type 1 and type 2 diabetes among children and adolescents from 2001 to 2009

IMPORTANCE

Despite concern about an "epidemic," there are limited data on trends in prevalence of either type 1 or type 2 diabetes across US race and ethnic groups.

OBJECTIVE

To estimate changes in the prevalence of type 1 and type 2 diabetes in US youth, by sex, age, and race/ethnicity between 2001 and 2009.

DESIGN, SETTING, AND PARTICIPANTS

Case patients were ascertained in 4 geographic areas and 1 managed health care plan. The study population was determined by the 2001 and 2009 bridged-race intercensal population estimates for geographic sites and membership counts for the health plan.

MAIN OUTCOMES AND MEASURES

Prevalence (per 1000) of physician-diagnosed type 1 diabetes in youth aged 0 through 19 years and type 2 diabetes in youth aged 10 through 19 years.

RESULTS

In 2001, 4958 of 3.3 million youth were diagnosed with type 1 diabetes for a prevalence of 1.48 per 1000 (95% CI, 1.44-1.52). In 2009, 6666 of 3.4 million youth were diagnosed with type 1 diabetes for a prevalence of 1.93 per 1000 (95% CI, 1.88-1.97). In 2009, the highest prevalence of type 1 diabetes was 2.55 per 1000 among white youth (95% CI, 2.48-2.62) and the lowest was 0.35 per 1000 in American Indian youth (95% CI, 0.26-0.47) and type 1 diabetes increased between 2001 and 2009 in all sex, age, and race/ethnic subgroups except for those with the lowest prevalence (age 0-4 years and American Indians). Adjusted for completeness of ascertainment, there was a 21.1% (95% CI, 15.6%-27.0%) increase in type 1 diabetes over 8 years. In 2001, 588 of 1.7 million youth were diagnosed with type 2 diabetes for a prevalence of 0.34 per 1000 (95% CI, 0.31-0.37). In 2009, 819 of 1.8 million were diagnosed with type 2 diabetes for a prevalence of 0.46 per 1000 (95% CI, 0.43-0.49). In 2009, the prevalence of type 2 diabetes was 1.20 per 1000 among American Indian youth (95% CI, 0.96-1.51); 1.06 per 1000 among black youth (95% CI, 0.93-1.22); 0.79 per 1000 among Hispanic youth (95% CI, 0.70-0.88); and 0.17 per 1000 among white youth (95% CI, 0.15-0.20). Significant increases occurred between 2001 and 2009 in both sexes, all age-groups, and in white, Hispanic, and black youth, with no significant changes for Asian Pacific Islanders and American Indians. Adjusted for completeness of ascertainment, there was a 30.5% (95% CI, 17.3%-45.1%) overall increase in type 2 diabetes.

CONCLUSIONS AND RELEVANCE

Between 2001 and 2009 in 5 areas of the United States, the prevalence of both type 1 and type 2 diabetes among children and adolescents increased. Further studies are required to determine the causes of these increases.

Mediators of 12-month outcomes of two Internet interventions for youth with type 1 diabetes

OBJECTIVE

To determine mediators of 12-month outcomes of Internet interventions for youth with type 1 diabetes transitioning to adolescence.

METHODS

In this multisite clinical trial, 320 youth were randomized to one of two Internet-based interventions: Coping skills (TEENCOPE™) or diabetes education (Managing Diabetes). Mediators of the interventions' effects on glycosylated hemoglobin and quality of life were examined. Data were collected at baseline and at 3, 6, and 12 months.

RESULTS

Self-efficacy mediated treatment effects on quality of life in both interventions. For TEENCOPE™, stress reactivity, primary control coping, and secondary control coping mediated treatment effects, whereas for Managing Diabetes, social acceptance mediated treatment effects. There were no significant effects of either intervention on glycosylated hemoglobin.

CONCLUSIONS

2 Internet interventions for youth with type 1 diabetes resulted in improved quality of life by different mechanisms, suggesting components of both diabetes education and coping skills may help to achieve better outcomes in youth with type 1 diabetes.

Direct medical costs for complications among children and adults with diabetes in the US commercial payer setting

BACKGROUND

Complications associated with diabetes are a major contributor to the burden of the disease. To better inform decision modelling, there is a need for cost estimates of specific diabetes-related complications, stratified by diabetes type and patient age group.

OBJECTIVE

To obtain direct medical costs of managing and treating diabetes-related complications over a 2-year period, for adults and children with type 1 diabetes mellitus (T1DM) or type 2 diabetes mellitus (T2DM), using data from a large commercially insured US subscriber database.

METHODS

We examined records from a large US multi-payer claims database to identify patients with any diabetes-related complications included in nine pre-specified categories, filed between January 2009 and September 2010, and with pre-index evidence of T1DM or T2DM. Patients were required to have continuous health plan enrolment 12 months before and 24 months after each index complication. Patients were classified into cohorts based on their diabetes type and age status at the time of the complication. The direct medical cost associated with each complication was calculated for the 12- and 24-month follow-up periods. Mean paid and allowed total costs were calculated and inflation-adjusted to the year 2011.

RESULTS

Of the 119,715 patients who met the inclusion criteria, 211 (0.2 %) were categorized as children with T1DM, 55 (0.05 %) as children with T2DM, 6,227 (5.2 %) as adults with T1DM and 113,222 (94.6 %) as adults with T2DM. The respective mean cohort ages were 13.5, 14.9, 48.5 and 58 years. Proteinuria/albuminuria was the most common complication for T1DM and T2DM child cohorts, with this complication occurring in almost one third of these children. Among the child cohorts, renal disease accounted for the highest mean paid cost for T1DM patients (US$6,053) whereas for T2DM patients, the complication associated with the highest mean paid cost was lactic acidosis (US$25,053). For the adult T1DM cohort, the complications with the highest occurrence and highest mean total paid cost were non-proliferative retinopathy (40.3 %) and renal disease (US$28,076), respectively. Similarly, for the adult T2DM cohort, these complications were neuropathy (26.8 %) and peritoneal dialysis (US$32,826).

CONCLUSION

With the continuing and increasing interest in child and adult T1DM and T2DM, stakeholders will need relevant and timely information to guide treatment decision making. This cost research may directly inform the economic models that are often developed to better identify, understand and manage key economic considerations that drive the costs of this chronic disease.

Barriers and facilitators to following the Dietary Guidelines for Americans reported by rural, Northern Plains American-Indian children

OBJECTIVE

The Dietary Guidelines for Americans (DGA) promote healthy dietary choices for all Americans aged 2 years and older; however, the majority of Americans do not meet recommendations. The goal of the present study was to identify both barriers and facilitators to adherence to DGA recommendations for consumption of five recommended food groups: grains (specifically whole grains), vegetables, fruits, meat/beans and milk (specifically reduced-fat/non-fat), among American-Indian children.

DESIGN

Nominal group technique sessions were conducted to identify and prioritize children's perceived barriers and facilitators to following the DGA, as presented in the 'MyPyramid' consumer education icon. After response generation to a single question about each food group (e.g. 'What sorts of things make it harder (or easier) for kids to follow the MyPyramid recommendation for vegetables?'), children individually ranked their top five most salient responses. Ranked responses are presented verbatim.

SETTING

A rural Northern Plains American-Indian reservation, USA.

SUBJECTS

Sixty-one self-selected fifth-grade children.

RESULTS

Core barriers for all food groups studied included personal preference (i.e. 'don't like') and environmental (i.e. 'cost too much'; 'store is too far to get them'; 'grandma don't have'). Core facilitators included suggestions, i.e. 'make a garden and plant vegetables'; 'tell your friends to eat healthy'.

CONCLUSIONS

Barriers and facilitators are dissimilar for individual food groups, suggesting that dietary interventions should target reduction of barriers and promotion of facilitators specific to individual food groups recommended by the DGA.

The many faces of diabetes: a disease with increasing heterogeneity

Diabetes is a much more heterogeneous disease than the present subdivision into types 1 and 2 assumes; type 1 and type 2 diabetes probably represent extremes on a range of diabetic disorders. Both type 1 and type 2 diabetes seem to result from a collision between genes and environment. Although genetic predisposition establishes susceptibility, rapid changes in the environment (ie, lifestyle factors) are the most probable explanation for the increase in incidence of both forms of diabetes. Many patients have genetic predispositions to both forms of diabetes, resulting in hybrid forms of diabetes (eg, latent autoimmune diabetes in adults). Obesity is a strong modifier of diabetes risk, and can account for not only a large proportion of the epidemic of type 2 diabetes in Asia but also the ever-increasing number of adolescents with type 2 diabetes. With improved characterisation of patients with diabetes, the range of diabetic subgroups will become even more diverse in the future.

Parent-child relationships in Type 1 diabetes: associations among child behavior, parenting behavior, and pediatric parenting stress

Interactions between parents and children can influence behavioral and emotional functioning related to Type 1 diabetes (T1D), yet have been relatively unexplored during preadolescence. The present study examined associations among child problem behaviors, critical parenting behaviors, and pediatric parenting stress in a sample of preadolescent youth with T1D. Data are available from 86 preadolescent-parent dyads who participated in the initial baseline assessment of a randomized controlled trial designed to assess the efficacy of an adherence promotion program. Measures included the Eyberg Child Behavior Inventory, the Diabetes Family Behavior Checklist, and the Pediatric Inventory for Parents. After controlling for significant demographic and medical characteristics, parents who reported their child's behavior as more problematic reported more difficulty with pediatric parenting stress, which was also associated with more child-reported critical parenting behaviors. Child problem behaviors and critical parenting behaviors were associated with one another, partially via their association with increased pediatric parenting stress. Potential clinical applications include interventions geared toward helping parents manage difficult child behaviors as well as cope with pediatric parenting stress, with the ultimate goal of improving the parent-child relationship and management of T1D.

Co-occurrence of risk alleles in or near genes modulating insulin secretion predisposes obese youth to prediabetes

OBJECTIVE

Paralleling the rise of pediatric obesity, the prevalence of impaired glucose tolerance (IGT) and type 2 diabetes (T2D) is increasing among youth. In this study, we asked whether the co-occurrence of risk alleles in or near five genes modulating insulin secretion (TCF7L2 rs7903146, IGF2BP2 rs4402960, CDKAL1 rs7754840, HHEX rs1111875, and HNF1A rs1169288) is associated with a higher risk of IGT/T2D in obese children and adolescents.

RESEARCH DESIGN AND METHODS

We studied 714 obese subjects (290 boys and 424 girls; mean age 13.6 ± 3.1 years; mean z score BMI 2.2 ± 0.4) and evaluated the insulin secretion by using the oral minimal model and, in a subgroup of 37 subjects, the hyperglycemic clamp. Also, 203 subjects were followed up for a mean of 2.1 years.

RESULTS

We observed that the increase of risk alleles was associated with a progressive worsening of insulin secretion (P < 0.001) mainly due to an impairment of the dynamic phase of insulin secretion (P = 0.004); the higher the number of the risk alleles, the higher the chance of progression from normal glucose tolerance (NGT) to IGT/T2D (P = 0.022). Also, for those who were IGT at baseline, a higher risk score was associated with a lower odds to revert to NGT (P = 0.026).

CONCLUSIONS

Obese children and adolescents developing IGT/T2D have a higher genetic predisposition than those who do not show these diseases, and this predisposition is mainly related to gene variants modulating the early phase of insulin secretion. Although these data are very interesting, they need to be replicated in other cohorts.

Forecasting the burden of type 2 diabetes in Singapore using a demographic epidemiological model of Singapore

OBJECTIVE

Singapore is a microcosm of Asia as a whole, and its rapidly ageing, increasingly sedentary population heralds the chronic health problems other Asian countries are starting to face and will likely face in the decades ahead. Forecasting the changing burden of chronic diseases such as type 2 diabetes in Singapore is vital to plan the resources needed and motivate preventive efforts.

METHODS

This paper describes an individual-level simulation model that uses evidence synthesis from multiple data streams-national statistics, national health surveys, and four cohort studies, and known risk factors-aging, obesity, ethnicity, and genetics-to forecast the prevalence of type 2 diabetes in Singapore. This comprises submodels for mortality, fertility, migration, body mass index trajectories, genetics, and workforce participation, parameterized using Markov chain Monte Carlo methods, and permits forecasts by ethnicity and employment status.

RESULTS

We forecast that the obesity prevalence will quadruple from 4.3% in 1990 to 15.9% in 2050, while the prevalence of type 2 diabetes (diagnosed and undiagnosed) among Singapore adults aged 18-69 will double from 7.3% in 1990 to 15% in 2050, that ethnic Indians and Malays will bear a disproportionate burden compared with the Chinese majority, and that the number of patients with diabetes in the workforce will grow markedly.

CONCLUSIONS

If the recent rise in obesity prevalence continues, the lifetime risk of type 2 diabetes in Singapore will be one in two by 2050 with concomitant implications for greater healthcare expenditure, productivity losses, and the targeting of health promotion programmes.

Validation of pediatric diabetes case identification approaches for diagnosed cases by using information in the electronic health records of a large integrated managed health care organization

We explored the utility of different algorithms for diabetes case identification by using electronic health records. Inpatient and outpatient diagnosis codes, as well as data on laboratory results and dispensing of antidiabetic medications were extracted from electronic health records of Kaiser Permanente Southern California members who were less than 20 years of age in 2009. Diabetes cases were ascertained by using the SEARCH for Diabetes in Youth Study protocol and comprised the "gold standard." Sensitivity, specificity, positive and negative predictive values, accuracy, and the area under the receiver operating characteristic curve (AUC) were compared in 1,000 bootstrapped samples. Based on data from 792,992 youth, of whom 1,568 had diabetes (77.2%, type 1 diabetes; 22.2%, type 2 diabetes; 0.6%, other), case identification accuracy was highest in 75% of bootstrapped samples for those who had 1 or more outpatient diabetes diagnoses or 1 or more insulin prescriptions (sensitivity, 95.9%; positive predictive value, 95.5%; AUC, 97.9%) and in 25% of samples for those who had 2 or more outpatient diabetes diagnoses and 1 or more antidiabetic medications (sensitivity, 92.4%; positive predictive value, 98.4%; AUC, 96.2%). Having 1 or more outpatient type 1 diabetes diagnoses (International Classification of Diseases, Ninth Revision, Clinical Modification, code 250.x1 or 250.x3) had the highest accuracy (94.4%) and AUC (94.1%) for type 1 diabetes; the absence of type 1 diabetes diagnosis had the highest accuracy (93.8%) and AUC (93.6%) for identifying type 2 diabetes. Information in the electronic health records from managed health care organizations provides an efficient and cost-effective source of data for childhood diabetes surveillance.

Breast-feeding initiation in women with pregestational diabetes mellitus

OBJECTIVE

To examine feeding practices and factors associated with breast-feeding initiation (BFI) in women with pregestational diabetes mellitus (PGDM) and their infants.

METHODS

In all, 392 PGDM (135 late preterm and 257 term) pregnancies were studied. Infant feeding preference was ascertained on admission.

RESULTS

After birth, 166 (42%) of the infants received well-baby care, whereas 226 (58%) were admitted to the newborn intensive care unit (NICU). Hypoglycemia (blood glucose <40 mg/dL), which occurred in 128 (33%) of all infants, did not influence BFI. Of 257 women who intended to BF, 55% initiated BF. Also, 5% of 105 women who intended to feed formula and 13% of the 30 undecided later initiated BF.

CONCLUSIONS

The BFI rate for women with PGDM is remarkably low even among those who intended to BF. Factors associated with BFI failure in this population were primiparity, African American race, lower education, smoking, lack of intention to BF, and NICU admission.

Quantitative Extrapolation: An Approach to Validation of Adult Drug Efficacy in Pediatric Subjects

Confirmation of efficacy in pediatric drug development has traditionally required large, fully powered efficacy studies that have proven to have major feasibility and ethical challenges. Extrapolation of efficacy in the framework provided by the US Food and Drug Administration and European Medicines Agency is an appropriate solution when there is similarity of disease. When there is uncertainty regarding the degree of disease similarity, partial extrapolation may be utilized. The authors propose a more quantitative approach to partial extrapolation (ie, quantitative extrapolation), involving (1) integration of adult pharmacokinetic (PK), pharmacodynamic (PD), and clinical outcome data using pharmacometric models, (2) extrapolation using the adult pharmacometric model to predict PD and efficacy outcomes in pediatric subjects, and (3) validation of pediatric predictions with a streamlined plan of pediatric trials (ie, a quantitative extrapolation plan). A case study is presented for quantitative extrapolation using dipeptidyl peptidase 4 (DPP-4) inhibitors. In this example, the authors demonstrate how adult PK, PD, and HbA1c data can be integrated using a pharmacometric model for DPP-4 inhibitors with pediatric dose selection and efficacy validated with relatively few pediatric subjects.

Early feeding and neonatal hypoglycemia in infants of diabetic mothers

Objectives:

To examine the effects of early formula feeding or breast-feeding on hypoglycemia in infants born to 303 A1-A2 and 88 Class B-RF diabetics.

Methods:

Infants with hypoglycemia (blood glucose < 40 mg/dL) were breast-fed or formula-fed, and those with recurrences were given intravenous dextrose.

Results:

Of 293 infants admitted to the well-baby nursery, 87 (30%) had hypoglycemia, corrected by early feeding in 75 (86%), while 12 (14%) required intravenous dextrose. In all, 98 infants were admitted to the newborn intensive care unit for respiratory distress (40%), prematurity (33%) or prevention of hypoglycemia (27%). Although all newborn intensive care unit patients received intravenous dextrose, 22 (22%) had hypoglycemia. Of 109 hypoglycemia episodes, 89 (82%) were single low occurrences. At discharge, 56% of well-baby nursery and 43% of newborn intensive care unit infants initiated breast-feeding.

Conclusions:

Hypoglycemia among infants of diabetic mothers can be corrected by early breast-feeding or formula feeding.

The growing prevalence of type 2 diabetes: increased incidence or improved survival?

Approximately 347 million persons were estimated to have diabetes worldwide in 2008, an increase of 194 million cases from 1980. Diabetes now affects both high- and low-income countries, with low-income countries bearing the majority of the burden. The epidemiologic transition from traditional health risks, such as poor hygiene, to modern health risks, such as sedentary lifestyle, has facilitated the increase in incidence in diabetes, especially in developing countries. The effect of these risk factors may be especially pronounced in some racial and ethnic populations. Increased surveillance for diabetes has contributed to increased diabetes prevalence in higher-income countries. Survival with and some risk factors for diabetes have improved in developed countries, but global diabetes mortality has increased by 20 % since 1990. Population growth and aging will only increase the burden of diabetes, and public health interventions are needed to address diabetes risk factors to stem the tide of this epidemic.

The emerging global epidemic of type 1 diabetes

Type 1 diabetes mellitus (T1D) can occur at any age, with a peak in incidence around puberty. Classification between T1D and type 2 diabetes becomes more challenging with increasing age of onset of T1D over time develops in genetically predisposed individuals. The main susceptibility is conferred with human leukocyte antigen (HLA) genes. Some of the geographic variation in incidence and familial aggregation is explained by differences in HLA haplotypes. In many populations, the incidence is somewhat higher in males than in females, and a 1.3- to 2.0-fold male excess in incidence after about 15 years of age exists in most populations. The incidence of childhood-onset T1D varies markedly among countries. East Asian and native American populations have low incidences (approximately 0.1-8 per 100 000/year), while the highest rates are found in Finland (>60 per 100 000/year), Sardinia (40 per 100 000/year), and Sweden (47 per 100 000/year). The risk is highest in European-derived populations. About 10 %-20 % of newly diagnosed childhood cases of T1D have an affected first-degree relative. Those with an affected sibling or parent have a cumulative risk of 3 %-7 % up to about 20 years of age, as compared with <1 % in the general population. The cumulative incidence among the monozygotic co-twins of persons with T1D is less than 50 %. Thus, the majority of genetically predisposed people do not develop T1D. Studies assessing temporal trends have shown that the incidence of childhood-onset T1D has increased in all parts of the world. The average relative increase is 3 %-4 % per calendar year. For instance, in Finland, the incidence today is 5 times higher than 60 years ago. At the same time, the age at onset of T1D in children has become younger. It is strongly believed that nongenetic factors are important for the development of T1D and its increase, but the causative evidence is missing. The causes for this increasing trend and current epidemic still remain unknown.

The ameliorative effect of Cetraria islandica against diabetes-induced genetic and oxidative damage in human blood

CONTEXT

The aqueous extracts of Cetraria islandica (L.) Ach. (Parmeliaceae) is traditionally used in many countries against a number of conditions, including inflammatory conditions.

OBJECTIVE

The present study aimed to assess, for the first time, the effectiveness of C. islandica in cultured primary blood cells of Type 1 diabetes subjects.

MATERIALS AND METHODS

Diabetic and control blood samples were treated with or without aqueous lichen extract (5 and 10 μg mL(-1)) for 48 h. The activity of antioxidant enzymes in erythrocytes and also malondialdehyde levels in plasma were determined to evaluate the oxidative status. DNA damages were analyzed by SCE, MN and comet assays in cultured human lymphocytes. Additionally, proliferation index (PI) was evaluated in peripheral blood lymphocytes.

RESULTS

There were significant increases in observed total DNA damage (comet assay) (240.2%) and SCE (168.8%), but not in MN frequencies of cultures with diabetes as compared (p > 0.05) to controls. Whereas, the significant reductions of total DNA damage (69.2 and 65.3%) and SCE frequencies (17.7 and 12.3%) were determined when the 5 and 10 mg mL(-1) lichen extract was added to the cell culture medium, respectively. However, lichen extract did not completely inhibit the induction of SCEs in lymphocytes of patients with diabetes. C. islandica extract was also useful on PI rates.

DISCUSSION

In conclusion, the antioxidant role of C. islandica in alleviating diabetes-induced genomic instability and for increasing cell viability was firstly indicated in the present study.