A dynamic Markov model for forecasting diabetes prevalence in the United States through 2050

Trends in lipid profiles and control of LDL-C among adults with diabetes in the United States: An analysis of NHANES 2007-2018

BACKGROUND AND AIM

To determine trends in lipid profiles and lipid control in US adults with diabetes and assess variation in these trends across sex and race/ethnicity from 2007 to 2018.

METHODS AND RESULTS

Serial cross-sectional analysis of data from diabetic adults participating in the National Health and Nutrition Examination Survey (NHANES; 2007-2008 to 2017-2018). Among the 6116 participants included (weighted mean age, 61.0 years; 50.7% men), age-adjusted TC (p for trend < 0.001), LDL-C (p for trend < 0.001), TG (p for trend = 0.006), TG/HDL-C (p for trend = 0.014) and VLDL-C (p for trend = 0.015) decreased significantly. Age-adjusted LDL-C levels were consistently higher in women than in men over the study period. Age-adjusted LDL-C improved significantly for diabetic whites and blacks but did not change significantly for the other races/ethnicity. Lipid parameters improved for non-coronary heart disease (CHD) diabetic adults, except for HDL-C, while no lipid parameter significantly changed for diabetic adults with concomitant CHD. Among diabetic adults receiving statin therapy, age-adjusted lipid control remained unchanged from 2007 to 2018, as did adults with concomitant CHD. However, age-adjusted lipid control improved significantly for men (p for trend < 0.01) and diabetic Mexican Americans (p for trend < 0.01). In 2015-2018, female diabetic participants receiving statins had lower odds of achieving lipid control (OR: 0.55; 95% CI: 0.35-0.84; P = 0.006) than men. Differences in lipid control across different races/ethnicities no longer existed.

CONCLUSIONS

Lipid profiles improved in the US adults with diabetes from 2007 to 2018. Although rates of lipid control did not improve nationally in adults receiving statins, these patterns varied by sex and race/ethnicity.

Invited Commentary: Mechanistic and Biologically Based Models in Epidemiology-A Powerful Underutilized Tool

Mechanistic and biologically based mathematical models of chronic and behavioral disease processes aim to capture the main mechanistic or biological features of the disease development and to connect these with epidemiologic outcomes. These approaches have a long history in epidemiologic research and are complementary to traditional epidemiologic or statistical approaches to investigate the role of risk factor exposures on disease risk. Simonetto et al. (Am J Epidemiol. 2022;191(10):1766-1775) present a mechanistic, process-oriented model to investigate the role of smoking, hypertension, and dyslipidemia in the development of atherosclerotic lesions and their progression to myocardial infarction. Their approach builds on and brings to cardiovascular disease the ideas and perspectives of earlier mechanistic and biologically based models for the epidemiology of cancer and other chronic diseases, providing important insights into the mechanisms and epidemiology of smoking related myocardial infarction. We argue that although mechanistic modeling approaches have demonstrated their value and place in epidemiology, they are highly underutilized. We call for efforts to grow mechanistic and biologically based modeling research, expertise, and awareness in epidemiology, including the development of training and collaboration opportunities to attract more students and researchers from science, technology, engineering, and medical field into the epidemiology field.

Cardiovascular disease and risk of incident diabetes mellitus: Findings from the Hispanic Community Health Study/Study of Latinos (HCHS/SOL)

BACKGROUND

Studies have reported an association between prevalent cardiovascular disease (CVD) and risk of diabetes mellitus (DM). However, factors that may explain the association remain unclear. We examined the association of prevalent CVD with incident DM and assessed whether weight gain and medication use may explain the association.

METHODS

Data from the Hispanic Community Health Study/Study of Latinos (HCHS/SOL) Visit 1 (2008-2011) and Visit 2 (2014-2017) were used to compare incidence of DM among individuals with and without self-reported CVD at Visit 1. A total of 1899 individuals with self-reported CVD were matched to controls free of self-reported CVD at Visit 1 using 1:1 propensity score matching. Covariates included in the propensity model were sociodemographic characteristics, lifestyle factors, comorbid conditions, and study site. The effect of self-reported CVD on incident DM was examined using a generalized estimating equation. The mediating effects of weight gain and use of cardiovascular medications were evaluated.

RESULTS

Covariate distributions were similar among individuals with and without self-reported CVD. The incidence of DM among persons with self-reported CVD was 15.3% vs 12.7% among those without self-reported CVD. Compared to individuals without self-reported CVD, individuals with self-reported CVD had a 24% increased risk for incident DM (odds ratio = 1.24, 95% confidence interval = 1.01, 1.51). The association between self-reported CVD and DM was mediated by the use of beta-blockers (proportion explained = 25.4%), statins (proportion explained = 18%), and diuretics (proportion explained = 8%). We found that weight gain did not explain the observed association.

CONCLUSIONS

Prevalent cardiovascular disease was associated with a significant increased risk of incident diabetes. The observed association was partially explained by some medications used to manage CVD.

Dietary knowledge, attitude and practice among type 2 diabetes mellitus patients in Sudan: a hospital-based cross-sectional study

Background

In Sudan, the prevalence of diabetes in adults was estimated at 19.1% in 2015. This study assessed dietary knowledge, attitude, and practices (KAP) of type 2 diabetes mellitus (T2DM) patients in Sudan.

Methods

We randomly selected 238 T2DM patients from a list of 2460 patients from the Jabber Abulizz Hospital. We interviewed them face-to-face using a structured questionnaire. Multivariate logistic regression analyses were performed to investigate the determinants of KAP regarding the recommended diets for T2DM patients.

Results

Majority of the patients demonstrated good knowledge (54.6%), positive attitude (79%); and good practice (58%). The result revealed that patients with formal education had 3.0 (95% CI: 1.6–5.7) times higher odds of having good diabetic dietary knowledge than those with informal education. While patients who had good knowledge and a positive attitude were respectively 4.7 (95% CI: 2.4–8.9) and 3.2 (95% CI: 1.5–6.7) times more likely to follow dietary recommendations than the patients with poor knowledge and negative attitudes.

Conclusion

Irrespective of the socio-demographic position, the good knowledge and the positive attitude towards the recommended diet, all the T2DM patients complied with the dietary recommendations. These findings highlight the need for improving knowledge and promoting positive attitudes towards the recommended diet among T2DM patients.

Is there an association between family history of diabetes mellitus and long-term cardiovascular hospitalizations of offspring?

OBJECTIVE

Gestational diabetes mellitus (GDM) was previously found to be an independent risk factor for long-term cardiovascular morbidity of parturients and their offspring. The objective of this study was to investigate the association between family history of diabetes mellitus (DM) in non-diabetic mothers and long-term pediatric cardiovascular hospitalizations of their offspring.

STUDY DESIGN

In a hospital-based cohort study, the incidence of cardiovascular disorders was compared between offspring of non-diabetic mothers with and without a family history of DM. Cardiovascular hospitalizations were assessed up until 18years of age according to a predefined set of ICD-9 codes associated with hospitalization of offspring. Exclusion criteria included multiple gestations, mothers with pre-gestational or gestational diabetes, lack of prenatal care, and children with congenital malformations and chromosomal abnormalities. A Kaplan-Meier survival curve was used to compare cumulative hospitalizations incidence. A cox proportional hazards model was performed to control for confounders.

RESULTS

A total of 208,728 deliveries were included in the study. Of them, 17,040 (8.2%) offspring were born to non-diabetic mothers with a family history of DM. Significant differences in the rates of IVF, induction of labor, obesity, hypertensive disorders of pregnancy, smoking and birth weight were found between the two study groups. Total cardiovascular hospitalizations were comparable between the study groups (0.6% vs. 0.7%, p=0.416). The Kaplan-Meier survival curve exhibited no difference in the cumulative incidence of total cardiovascular hospitalizations of the offspring (log-rank test, p=0.271). A Cox regression model found that a family history of DM in non-diabetic mothers was not independently associated with long-term cardiovascular hospitalizations of the offspring after controlling for the following confounders: maternal age, birth weight, caesarian section and maternal hypertensive disorders (aHR=1.130, 95% CI 0.930-1.374, p=0.220).

CONCLUSION

A family history of DM in non-diabetic parturients, does not increase the risk for cardiovascular hospitalizations of their offspring.

A system dynamics modelling simulation based on a cohort of hepatitis B epidemic research in east China community

Hepatitis B constitutes a severe public health challenge in China. The Community-based Collaborative Innovation hepatitis B (CCI-HBV) project is a national epidemiological study of hepatitis B and has been conducting a comprehensive intervention in southern Zhejiang since 2009.The comprehensive intervention in CCI-HBV areas includes the dynamic hepatitis B screening in local residents, the normalised treatment for hepatitis B infections and the upcoming full-aged hepatitis B vaccination. After two rounds of screening (each round taking for 4 years), the initial epidemiological baseline of hepatitis B in Qinggang was obtained, a coastal community in east China. By combining key data and system dynamics modelling, the regional hepatitis B epidemic in 20 years was predicted.There were 1041 HBsAg positive cases out of 12 228 people in Round 1 indicating HBV prevalence of 8.5%. Of the 13 146 people tested in Round 2, 1171 people were HBsAg positive, with a prevalence of 8.9%. By comparing the two rounds of screening, the HBV incidence rate of 0.192 per 100 person-years was observed. By consulting electronic medical records, the HBV onset rate of 0.533 per 100 person-years was obtained. We generated a simulated model to replicate the real-world situation for the next two decades. To evaluate the effect of interventions on regional HBV prevalence, three comparative experiments were conducted.In this study, the regional hepatitis B epidemic in 20 years was predicted and compared with HBV prevalence under different interventions. Owing to the existing challenges in research methodology, this study combined HBV field research and simulation to provide a system dynamics model with close-to-real key data to improve prediction accuracy. The simulation also provided a prompt guidance for the field implementation.

Projection of Diabetes Prevalence in Korean Adults for the Year 2030 Using Risk Factors Identified from National Data

BACKGROUND

A number of studies have reported future prevalence estimates for diabetes mellitus (DM), but these studies have been limited for the Korean population. The present study aimed to construct a forecasting model that includes risk factors for type 2 DM using individual- and national-level data for Korean adults to produce prevalence estimates for the year 2030.

METHODS

Time series data from the Korea National Health and Nutrition Examination Survey and national statistics from 2005 to 2013 were used. The study subjects were 13,908 male and 18,697 female adults aged 30 years or older who were free of liver cirrhosis. Stepwise logistic regression analysis was used to select significant factors associated with DM prevalence.

RESULTS

The results showed that survey year, age, sex, marital, educational, or occupational status, the presence of obesity or hypertension, smoking status, alcohol consumption, sleep duration, psychological distress or depression, and fertility rate significantly contributed to the 8-year trend in DM prevalence (P<0.05). Based on sex-specific forecasting models that included the above factors, DM prevalence for the year 2030 was predicted to be 29.2% (95% confidence interval [CI], 27.6% to 30.8%) in men and 19.7% (95% CI, 18.2% to 21.2%) in women.

CONCLUSION

The present study projected a two-fold increase in the prevalence of DM in 2030 compared with that for the years 2013 and 2014 in Korean adults. Modifiable factors contributing to this increase in DM prevalence, such as obesity, smoking, and psychological factors, may require attention in order to reduce national and individual costs associated with DM.

A forecasting model of disease prevalence based on the McKendrick-von Foerster equation

A new model for disease prevalence based on the analytical solutions of McKendric-von Foerster's partial differential equations is developed. Derivation of the model and methods to cross check obtained results are explicitly demonstrated. Obtained equations describe the time evolution of the healthy and unhealthy age-structured sub-populations and age patterns of disease prevalence. The projection of disease prevalence into the future requires estimates of time trends of age-specific disease incidence, relative survival functions, and prevalence at the initial age and year available in the data. The computational scheme for parameter estimations using Medicare data, analytical properties of the model, application for diabetes prevalence, and relationship with partitioning models are described and discussed. The model allows natural generalization for the case of several diseases as well as for modeling time trends in cause-specific mortality rates.

Age × stage-classified demographic analysis: a comprehensive approach

This paper presents a comprehensive theory for the demographic analysis of populations in which individuals are classified by both age and stage. The earliest demographic models were age classified. Ecologists adopted methods developed by human demographers and used life tables to quantify survivorship and fertility of cohorts and the growth rates and structures of populations. Later, motivated by studies of plants and insects, matrix population models structured by size or stage were developed. The theory of these models has been extended to cover all the aspects of age-classified demography and more. It is a natural development to consider populations classified by both age and stage. A steady trickle of results has appeared since the 1960s, analyzing one or another aspect of age × stage-classified populations, in both ecology and human demography. Here, we use the vec-permutation formulation of multistate matrix population models to incorporate age- and stage-specific vital rates into demographic analysis. We present cohort results for the life table functions (survivorship, mortality, and fertility), the dynamics of intra-cohort selection, the statistics of longevity, the joint distribution of age and stage at death, and the statistics of life disparity. Combining transitions and fertility yields a complete set of population dynamic results, including population growth rates and structures, net reproductive rate, the statistics of lifetime reproduction, and measures of generation time. We present a complete analysis of a hypothetical model species, inspired by poecilogonous marine invertebrates that produce two kinds of larval offspring. Given the joint effects of age and stage, many familiar demographic results become multidimensional, so calculations of marginal and mixture distributions are an important tool. From an age-classified point of view, stage structure is a form of unobserved heterogeneity. From a stage-classified point of view, age structure is unobserved heterogeneity. In an age × stage-classified model, variance in demographic outcomes can be partitioned into contributions from both sources. Because these models are formulated as matrices, they are amenable to a complete sensitivity analysis. As more detailed and longer longitudinal studies are developed, age × stage-classified demography will become more common and more important.

Projecting the Burden of Chronic Kidney Disease in a Developed Country and Its Implications on Public Health

BACKGROUND

Chronic Kidney Disease (CKD) is a major public health problem worldwide. There is limited literature on a model to project the number of people with CKD. This study projects the number of residents with CKD in Singapore by 2035 using a Markov model.

METHODS

A Markov model with nine mutually exclusive health states was developed according to the clinical course of CKD, based on a discrete time interval of 1 year. The model simulated the transition of cohorts across different health states from 2007 to 2035 using prevalence, incidence, mortality, disease transition, and disease detection rates.

RESULTS

From 2007 to 2035, the number of residents with CKD is projected to increase from 316,521 to 887,870 and the prevalence from 12.2% to 24.3%. Patients with CKD stages 1-2 constituted the largest proportion. The proportion of undiagnosed cases will decline from 72.1% to 56.4%, resulting from faster progression to higher CKD stages and its eventual detection.

CONCLUSION

By 2035, about one-quarter of the Singapore residents are expected to have CKD. National policies need to focus on primary disease prevention and early disease detection to avoid delayed treatment of CKD which eventually leads to end-stage renal disease.

Projection of the future diabetes burden in the United States through 2060

Background

In the United States, diabetes has increased rapidly, exceeding prior predictions. Projections of the future diabetes burden need to reflect changes in incidence, mortality, and demographics. We applied the most recent data available to develop an updated projection through 2060.

Methods

A dynamic Markov model was used to project prevalence of diagnosed diabetes among US adults by age, sex, and race (white, black, other). Incidence and current prevalence were from the National Health Interview Survey (NHIS) 1985–2014. Relative mortality was from NHIS 2000–2011 follow-up data linked to the National Death Index. Future population estimates including birth, death, and migration were from the 2014 Census projection.

Results

The projected number and percent of adults with diagnosed diabetes would increase from 22.3 million (9.1%) in 2014 to 39.7 million (13.9%) in 2030, and to 60.6 million (17.9%) in 2060. The number of people with diabetes aged 65 years or older would increase from 9.2 million in 2014 to 21.0 million in 2030, and to 35.2 million in 2060. The percent prevalence would increase in all race-sex groups, with black women and men continuing to have the highest diabetes percent prevalence, and black women and women of other race having the largest relative increases.

Conclusions

By 2060, the number of US adults with diagnosed diabetes is projected to nearly triple, and the percent prevalence double. Our estimates are essential to predict health services needs and plan public health programs aimed to reduce the future burden of diabetes.

Electronic supplementary material

The online version of this article (10.1186/s12963-018-0166-4) contains supplementary material, which is available to authorized users.

Protective role of physical activity on type 2 diabetes: Analysis of effect modification by race-ethnicity

BACKGROUND

It is well known physical activity (PA) plays a role in the prevention of type 2 diabetes (T2D). However, the extent to which PA may affect T2D risk among different race-ethnic groups is unknown. Therefore, the aim of the present study was to systematically examine the effect modification of race-ethnicity on PA and T2D.

METHODS

The PubMed and Embase databases were systematically searched through June 2016. Study assessment for inclusion was conducted in three phases: title review (n = 13 022), abstract review (n = 2200), and full text review (n = 265). In all, 27 studies met the inclusion criteria and were used in the analysis. Relative risks (RRs) and 95% confidence intervals (CIs) were extracted and analyzed using Comprehensive Meta-Analysis software. All analyses used a random-effects model.

RESULTS

A significant protective summary RR, comparing the most active group with the least active PA group, was found for non-Hispanic White (RR 0.71, 95% CI 0.60-0.85), Asians (RR 0.76, 95% CI 0.67-0.85), Hispanics (RR 0.75, 95% CI 0.64-0.89), and American Indians (RR 0.73, 95% CI 0.60-0.88). The summary effect for non-Hispanic Blacks (RR 0.91, 95% CI 0.76-1.08) was not significant.

CONCLUSIONS

The results of the present study indicate that PA (comparing most to least active groups) provides significant protection from T2D, with the exception of non-Hispanic Blacks. The results also indicate a need for race-ethnicity-specific reporting of RRs in prospective cohort studies that incorporate multiethnic samples.

Incremental Treatment Costs Attributable to Overweight and Obesity in Patients with Diabetes: Quantile Regression Approach

OBJECTIVE

This study aimed to estimate treatment costs attributable to overweight and obesity in patients with diabetes who were less than 65 years of age in the United States.

METHODS

This study used data from the Medical Expenditure Panel Survey from 2001 to 2013. Patients with diabetes were identified by using the International Classification of Diseases, Ninth Revision, Clinical Modification code (250), clinical classification codes (049 and 050), or self-reported physician diagnoses. Total treatment costs attributable to overweight and obesity were calculated as the differences in the adjusted costs compared with individuals with diabetes and normal weight. Adjusted costs were estimated by using generalized linear models or unconditional quantile regression models.

RESULTS

The mean annual treatment costs attributable to obesity were $1,852 higher than those attributable to normal weight, while costs attributable to overweight were $133 higher. The unconditional quantile regression results indicated that the impact of obesity on total treatment costs gradually became more significant as treatment costs approached the upper quantile.

CONCLUSIONS

Among patients with diabetes who were less than 65 years of age, patients with diabetes and obesity have significantly higher treatment costs than patients with diabetes and normal weight. The economic burden of diabetes to society will continue to increase unless more proactive preventive measures are taken to effectively treat patients with overweight or obesity.

Projection of prediabetes and diabetes population size in Singapore using a dynamic Markov model

BACKGROUND

The aim of the present study was to forecast the prevalence and number of adult Singapore residents with prediabetes and diabetes in 2035.

METHODS

A dynamic Markov model with nine mutually exclusive states was developed based on the clinical course of diabetes using time-dependent rates and probabilities. A 1-year cycle over a 25-year time horizon from 2010 to 2035 was used in the model. With publicly available data and a chronic disease register, the model forecast annual disease burden by simulating transition of cohorts across different health states using prevalence rates, incidence rates, mortality rates, disease transition, disease detection, and complication rates. An aging index was used in the model in anticipation of population aging to minimize risks of underestimating disease burden.

RESULTS

From 2010 to 2035, the number of Singapore residents with prediabetes and diabetes is projected to more than double, from 434 685 to 903 596 and from 373 104 to 823 802, respectively. The prevalence of prediabetes and diabetes will rise steadily from 15.5 % to 24.9 % and from 13.3 % to 22.7 %, respectively. By 2035, a further estimate of 733 174 and 100 250 patients with prediabetes and uncomplicated diabetes, respectively, will remain undiagnosed. The prevalence of detected and undetected complications is forecast to rise from 60.0 % in 2010 to 70.2 % by 2035.

CONCLUSION

By 2035, the prevalence of prediabetes and diabetes among Singapore residents aged 21+ years is expected to be one in four and one in five, respectively. There is an impetus to adopt more aggressive interventions to contain disease progression.

The State of the Science on Nursing Best Practices for Diabetes Self-Management

Jane Jeffrie Seley is a diabetes nurse practitioner at New York Presbyterian—Weill Cornell Medical Center, New York City. She is a contributing editor and the column coordinator for Diabetes Under Control in the American Journal of Nursing. Katie Weinger is an investigator in behavioral and mental health research, director of the Center of Innovation in Diabetes Education and of the Office of Research Fellow Affairs at Joslin Diabetes Center, and an assistant professor of psychiatry at Harvard Medical School, all in Boston. She has received a grant from the National Institutes of Health (NIDDK60115) to study breaking down barriers to diabetes self-care. Contact author: Jane Jeffrie Seley, diabetesnp@gmail.com. Seley serves on the advisory boards of Abbott Diabetes Care, Amylin Pharmaceuticals, Sanofi-Aventis Pharmaceuticals, Pfizer Pharmaceuticals, Roche Diagnostics, Bayer Diabetes Care, Novo Nordisk Pharmaceuticals, and GlaxoSmithKline Pharmaceuticals, several of which provided funding for the project discussed in this article. The authors have no other significant ties, financial or otherwise, to any company that might have an interest in the publication of this educational activity.

Diabetes and neurodegeneration in the brain

Although an association between diabetes mellitus (DM) and cognitive dysfunction has been recognized for a century, it is often not considered as a complication of DM and remains under-recognized. Cognitive dysfunction, usually present as mild cognitive impairment, can occur with either type 1 or type 2 DM. Both forms of DM contribute to accelerated cerebral atrophy and to the presence of heightened white matter abnormalities. These effects are noted most at the two extremes of life, in childhood and in the advanced years. The cognitive spheres most affected include attention and executive function, processing speed, perception, and memory. Although DM is unlikely to lead to frank dementia, its ability to exacerbate existing neurodegenerative processes, such as Alzheimer disease, will impact tremendously upon our society in the upcoming decades as our population ages. This chapter describes the clinical impact of DM upon the brain, along with discussion of the potential therapeutic avenues to be discovered in the coming decades. We need to prepare for better preventative and therapeutic management of this cerebral neurodegenerative condition.

Burden of type 2 diabetes in Mexico: past, current and future prevalence and incidence rates

INTRODUCTION

Mexico diabetes prevalence has increased dramatically in recent years. However, no national incidence estimates exist, hampering the assessment of diabetes trends and precluding the development of burden of disease analyses to inform public health policy decision-making. Here we provide evidence regarding current magnitude of diabetes in Mexico and its future trends.

METHODS

We used data from the Mexico National Health and Nutrition Survey, and age-period-cohort models to estimate prevalence and incidence of self-reported diagnosed diabetes by age, sex, calendar-year (1960-2012), and birth-cohort (1920-1980). We project future rates under three alternative incidence scenarios using demographic projections of the Mexican population from 2010-2050 and a Multi-cohort Diabetes Markov Model.

RESULTS

Adult (ages 20+) diagnosed diabetes prevalence in Mexico increased from 7% to 8.9% from 2006 to 2012. Diabetes prevalence increases with age, peaking around ages 65-68 to then decrease. Age-specific incidence follows similar patterns, but peaks around ages 57-59. We estimate that diagnosed diabetes incidence increased exponentially during 1960-2012, roughly doubling every 10 years. Projected rates under three age-specific incidence scenarios suggest diabetes prevalence among adults (ages 20+) may reach 13.7-22.5% by 2050, affecting 15-25 million individuals, with a lifetime risk of 1 in 3 to 1 in 2.

CONCLUSIONS

Diabetes prevalence in Mexico will continue to increase even if current incidence rates remain unchanged. Continued implementation of policies to reduce obesity rates, increase physical activity, and improve population diet, in tandem with diabetes surveillance and other risk control measures is paramount to substantially reduce the burden of diabetes in Mexico.

Improving Detection of Prediabetes in Children and Adults: Using Combinations of Blood Glucose Tests

Highlights

Aim

To determine combinations of blood glucose tests: oral glucose tolerance (OGT), fasting plasma glucose (FPG), and hemoglobin A1C (HbA1C) that are associated with highest diagnostic rates of prediabetes in non-diabetic American children and adults.

Methods

The 2007–2008 U.S. National Health and Nutrition Examination Surveys data were used for this study. Overall and specific prevalence of prediabetes (defined using OGT + FPG, OGT + HbA1C, HbA1C + FPG, and OGT + FPG + HbA1C tests) were determined across age, race/ethnicity, sex, and BMI categories.

Results

FPG + HbA1C test was associated with significantly higher diagnostic rates of prediabetes across age, race/ethnicity, and BMI. Estimates of overall prevalence of prediabetes using OGT + FPG, OGT + HbA1C, HbA1C + FPG, and OGT + FPG + HbA1C tests were 20.3, 24.2, 33, and 34.3%, respectively. Compared to OGT + FPG, the use of HbA1C + FPG test in screening was associated with 44.8, 135, 38.6, and 35.9% increased prevalence of prediabetes in non-Hispanic White, non-Hispanic Black, Mexican-American, and other racial/ethnic men, respectively. The corresponding values in women were 67.8, 140, 37.2, and 42.6%, respectively. Combined use of all blood glucose tests did not improve the overall and gender-specific prediabetes prevalence beyond what was observed using HbA1C + FPG test.

Conclusion

HbA1C criteria were associated with higher diagnosis rates of prediabetes than FPG and OGT tests in non-diabetic American children and adults. Using a combination of HbA1C and FPG test in screening for prediabetes reduces intrinsic systematic bias in using just HbA1C testing and offers the benefits of each test. A well-defined HbA1C that takes into consideration race/ethnicity, gender, age, and body mass index may improve detection of prediabetes in population and clinical settings.

Projection of Diabetes Population Size and Associated Economic Burden through 2030 in Iran: Evidence from Micro-Simulation Markov Model and Bayesian Meta-Analysis

Background

The aim of this study was to estimate the economic burden of diabetes mellitus (DM) in Iran from 2009 to 2030.

Methods

A Markov micro-simulation (MM) model was developed to predict the DM population size and associated economic burden. Age- and sex-specific prevalence and incidence of diagnosed and undiagnosed DM were derived from national health surveys. A systematic review was performed to identify the cost of diabetes in Iran and the mean annual direct and indirect costs of patients with DM were estimated using a random-effect Bayesian meta-analysis. Face, internal, cross and predictive validity of the MM model were assessed by consulting an expert group, performing sensitivity analysis (SA) and comparing model results with published literature and national survey reports. Sensitivity analysis was also performed to explore the effect of uncertainty in the model.

Results

We estimated 3.78 million cases of DM (2.74 million diagnosed and 1.04 million undiagnosed) in Iran in 2009. This number is expected to rise to 9.24 million cases (6.73 million diagnosed and 2.50 million undiagnosed) by 2030. The mean annual direct and indirect costs of patients with DM in 2009 were US$ 556 (posterior standard deviation, 221) and US$ 689 (619), respectively. Total estimated annual cost of DM was $3.64 (2009 US$) billion (including US$1.71 billion direct and US$1.93 billion indirect costs) in 2009 and is predicted to increase to $9.0 (in 2009 US$) billion (including US$4.2 billion direct and US$4.8 billion indirect costs) by 2030.

Conclusions

The economic burden of DM in Iran is predicted to increase markedly in the coming decades. Identification and implementation of effective strategies to prevent and manage DM should be considered as a public health priority.

Projection of osteoporosis-related fractures and costs in China: 2010-2050

A state-transition microsimulation model was used to project the substantial economic burden to the Chinese healthcare system of osteoporosis-related fractures. Annual number and costs of osteoporosis-related fractures were estimated to double by 2035 and will increase to 5.99 (95 % CI 5.44, 6.55) million fractures costing $25.43 (95 % CI 23.92, 26.95) billion by 2050. Consequently, cost-effective intervention policies must urgently be identified in an attempt to minimize the impact of fractures.

INTRODUCTION

The aim of the study was to project the osteoporosis-related fractures and costs for the Chinese population aged ≥50 years from 2010 to 2050.

METHODS

A state-transition microsimulation model was used to simulate the annual incident fractures and costs. The simulation was performed with a 1-year cycle length and from the Chinese healthcare system perspective. Incident fractures and annual costs were estimated from 100 unique patient populations for year 2010, by multiplying the age- and sex-specific annual fracture risks and costs of fracture by the corresponding population totals in each of the 100 categories. Projections for 2011-2050 were performed by multiplying the 2010 risks and costs of fracture by the respective annual population estimates. Costs were presented in 2013 US dollars.

RESULTS

Approximately 2.33 (95 % CI 2.08, 2.58) million osteoporotic fractures were estimated to occur in 2010, costing $9.45 (95 % CI 8.78, 10.11) billion. Females sustained approximately three times more fractures than males, accounting for 76 % of the total costs from 1.85 (95 % CI 1.68, 2.01) million fractures. The annual number and costs of osteoporosis-related fractures were estimated to double by 2035 and will increase to 5.99 (95 % CI 5.44, 6.55) million fractures costing $25.43 (95 % CI 23.92, 26.95) billion by 2050.

CONCLUSIONS

Our study demonstrated that osteoporosis-related fractures cause a substantial economic burden which will markedly increase over the coming decades. Consequently, healthcare resource planning must consider these increasing costs, and cost-effective screening and intervention policies must urgently be identified in an attempt to minimize the impact of fractures on the health of the burgeoning population as well as the healthcare budget.

Nonalcoholic Fatty liver disease and risk of diabetes and cardiovascular disease: what is important for primary care physicians?

Nonalcoholic fatty liver disease (NAFLD) is emerging as the most common chronic liver condition in Western World and across the globe. NAFLD prevalence is estimated to be around one-third of the total population. There are no published data that project the future prevalence of NAFLD, but with an increase in epidemic of diabetes and obesity, it is possible to suggest an increase in a number of individuals with NAFLD. NAFLD is associated with insulin resistance and occurs with an increase in cluster of features of metabolic syndrome and type 2 diabetes. Therefore, it is important to exclude the possibility of diabetes in those individuals with evidence of fatty liver. The global diabetes epidemic continues to grow, and it is estimated that the number of people with diabetes will double by year 2030. NAFLD is also a risk factor for an increase in cardiovascular incidence independent of age, sex, low-density lipoprotein-cholesterol, smoking, and cluster of metabolic syndromes. It is expected that NAFLD will be an important challenge for health providers in the near future. Taking all these factors into consideration, we believe that increasing awareness of metabolic and cardiovascular impact of NAFLD among general practitioners and health authorities may decrease the serious consequences of late diagnosis of NAFLD. Importantly, the collaboration between medical specialties is vital in decreasing the impact of the epidemic of NAFLD. The focus of this review is in the role of primary care physician in diagnosis, treatment and prevention of NAFLD and patients education.

Antihyperglycemic effects of Pandanus amaryllifolius Roxb. leaf extract

Background:

Diabetes mellitus is one of the leading chronic diseases worldwide. In patients with poor glycemic control, high blood glucose level may lead to other life-threatening complications. Pandanus amaryllifolius Roxb. (PA) leaves are used in traditional medicine for the treatment of diabetes.

Objective:

This study evaluated the effect of crude extract from PA leaves on blood glucose level and the hypoglycemic mechanisms.

Materials and Methods:

Thirty healthy volunteers were asked to drink PA tea (test-group) or hot water (control group) 15 min after glucose loading (75 g) in a standard oral glucose tolerance test. To study hypoglycemic mechanisms, PA leaves were extracted using two different methods. Method 1; dried PA leaves were extracted with distilled water at 90°C for 15 min, and method 2; dried PA leaves were extracted with 95% ethanol. Both PA extracts were tested for α-glucosidase enzyme inhibition, insulin stimulation, and glucose uptake stimulation.

Results:

The average of blood glucose level in the control group was 5.55 ± 0.98 mmol/l, while in PA treated group was 6.16 ± 0.79 mmol/l which were statistically different (P < 0.001). The results of antihyperglycemic mechanism showed that PA extracts, prepared both methods, could inhibit α-glucosidase enzyme and induce insulin production in rat pancreatic cell (RINm5F) in dose-dependent manner (P < 0.05).

Conclusions:

The knowledge gained from this research can be used as a basis for a new drug discovery for the treatment of diabetes.

Is diabetes color-blind? Growth of prevalence of diagnosed diabetes in children through 2030

Diabetes knows no age and affects millions of individuals. Preventing diabetes in children is increasingly becoming a major health policy concern and focus. The objective of this study is to project the number of children, aged 0-17 years, with diagnosed diabetes in the United States through 2030, accounting for changing demography, and diabetes and obesity prevalence rates. The study team combined historic diabetes and obesity prevalence data with US child population estimates and projections. A times-series regression model was used to forecast future diabetes prevalence and to account for the relationship between the forecasted diabetes prevalence and the lagged prevalence of childhood obesity. Overall, the prevalence of diagnosed diabetes is projected to increase 67% from 0.22% in 2010 to 0.36% in 2030. Lagged obesity prevalence in Hispanic boys and non-Hispanic black girls was significantly associated with increasing future diabetes prevalence. The study results showed that a 1% increase in obesity prevalence among Hispanic boys from the previous year was significantly associated with a 0.005% increase in future prevalence of diagnosed diabetes in children (P ≤ 0.01). Likewise, a unit increase in obesity prevalence among non-Hispanic black girls was associated with a 0.003% increase in future diabetes prevalence (P < 0.05). Obesity rates for other race/ethnicity combinations were not associated with increasing future diabetes prevalence. To mitigate the continued threat posed by diabetes, serious discussions need to focus on the pediatric population, particularly non-Hispanic black girls and Hispanic boys whose obesity trends show the strongest associations with future diabetes prevalence in children.

Population attributable fraction of type 2 diabetes due to physical inactivity in adults: a systematic review

Background

Physical inactivity is a global pandemic. The population attributable fraction (PAF) of type 2 diabetes mellitus (T2DM) associated with physical inactivity ranges from 3% to 40%. The purpose of this systematic review was to determine the best estimate of PAF for T2DM attributable to physical inactivity and absence of sport participation or exercise for men and women.

Methods

We conducted a systematic review that included a comprehensive search of MEDLINE, EMBASE, SportDiscus, and CINAHL (1946 to April 30 2013) limited by the terms adults and English. Two reviewers screened studies, extracted PAF related data and assessed the quality of the selected studies. We reconstructed 95% CIs for studies missing these data using a substitution method.

Results

Of the eight studies reporting PAF in T2DM, two studies included prospective cohort studies (3 total) and six were reviews. There were distinct variations in quality of defining and measuring physical inactivity, T2DM and adjusting for confounders. In the US, PAFs for absence of playing sport ranged from 13% (95% CI: 3, 22) in men and 29% (95% CI: 17, 41) in women. In Finland, PAFs for absence of exercise ranged from 3% (95% CI: -11, 16) in men to 7% (95% CI: -9, 20) in women.

Conclusions

The PAF of physical inactivity due to T2DM is substantial. Physical inactivity is a modifiable risk factor for T2DM. The contribution of physical inactivity to T2DM differs by sex; PAF also differs if physical inactivity is defined as the absence of ‘sport’ or absence of ‘exercise’.

Racial comparisons of diabetes care and intermediate outcomes in a patient-centered medical home

OBJECTIVE To assess racial differences in diabetes processes and intermediate outcomes of care in an internal medicine, patient-centered medical home (PCMH) group practice. RESEARCH DESIGN AND METHODS We conducted a retrospective cohort study of 1,457 adults with diabetes receiving care from 89 medical providers within a PCMH-designated academic practice between 1 July 2009 and 31 July 2010. We used mixed models to assess independent associations between patient race (non-Hispanic white or black) and 1) receipt of processes of care (A1C and LDL testing, foot and retinal examination, and influenza and pneumococcal vaccination) and 2) achievement of intermediate outcomes (LDL <100 mg/dL, blood pressure [BP] <140/90 mmHg, A1C <7.0% [<53 mmol/mol], and A1C >9.0% [>75 mmol/mol]), controlling for sociodemographic factors, health status, treatment intensity, and clinical continuity. RESULTS Compared with non-Hispanic white patients, black patients were younger, were more often single, had lower educational attainment, and were less likely to have commercial insurance. In unadjusted analyses, fewer black patients received a retinal examination and influenza vaccination during the study period or any lifetime pneumococcal vaccination (P < 0.05 [all comparisons]). Fewer black patients achieved an LDL <100 mg/dL, BP <140/90 mmHg, or A1C <7.0% (<53 mmol/mol), while more black patients had an A1C >9.0% (>75 mmol/mol) (P < 0.05 [all comparisons]). In multivariable models, black patients were less likely to receive A1C testing (odds ratio [OR] 0.57 [95% CI 0.34-0.95]) or influenza vaccination (OR 0.75 [95% CI 0.57-0.99]) or to achieve an LDL <100 mg/dL (OR 0.74 [95% CI 0.55-0.99]) or BP <140/90 mmHg (OR 0.64 [95% CI 0.49-0.84]). CONCLUSIONS Racial differences in processes and intermediate outcomes of diabetes care were present within this PCMH-designated practice, controlling for differences in sociodemographic, clinical, and treatment factors.

Diabetic foot ulcers: Part I. Pathophysiology and prevention

Diabetes mellitus is a serious, life-long condition that is the sixth leading cause of death in North America. Dermatologists frequently encounter patients with diabetes mellitus. Up to 25% of patients with diabetes mellitus will develop diabetic foot ulcers. Foot ulcer patients have an increased risk of amputation and increased mortality rate. The high-risk diabetic foot can be identified with a simplified screening, and subsequent foot ulcers can be prevented. Early recognition of the high-risk foot and timely treatment will save legs and improve patients' quality of life. Peripheral arterial disease, neuropathy, deformity, previous amputation, and infection are the main factors contributing to the development of diabetic foot ulcers. Early recognition of the high-risk foot is imperative to decrease the rates of mortality and morbidity. An interprofessional approach (ie, physicians, nurses, and foot care specialists) is often needed to support patients' needs.

Emerging drugs for the treatment of diabetic ulcers

INTRODUCTION

Diabetic ulcers are chronic nonhealing ulcerations that despite the available medical tools still result in high amputation rates. Growing evidence suggests that alteration of the biochemical milieu of the chronic wound plays a significant role in impaired diabetic wound healing.

AREAS COVERED

The basic pathophysiology and the conventional treatment strategy of diabetic foot ulcers have been reviewed in the first section. In the second part, the most up-to-date bench and translational research in the field are described. The third section focuses on the drugs currently under development and the ongoing clinical trials evaluating their safety and efficacy. Finally, the major drug development issues and the possible scientific approaches to overcome them are analyzed.

EXPERT OPINION

Significant strides in understanding the chronic wound development have led to the development of topical therapies to address aberrant expression of growth factors and overexpression of inflammatory cytokines. Current research in the laboratory suggests that while decreased growth factor expression occurs at the local wound level, increased systemic serum levels of growth factors suggest growth factor resistance.

Prevalence of type 2 diabetes in Germany in 2040: estimates from an epidemiological model

To estimate the number of persons in the age-group 55-74 years with type 2 diabetes in Germany until 2040 and to analyze the impact of an intervention in a high risk group. A Markov model is used to generate forecasts by age and sex in each year using inputs of estimated diabetes prevalence, incidence and mortality based on actual national data. Projections about future demographics stem from the German Federal Office of Statistics. In a slightly modified model a state for persons with prediabetes is included to study the interplay of effect-size and participation quote on the number of persons with diabetes. The projected number of people with type 2 diabetes aged 55-74 years rises from 2.4 million in 2010 to 3.9 million in 2030. From 2030 on this number will decrease slightly to 3.3 million in 2040. If every second person aged 55-74 with prediabetes took part in a prevention program with the effect size of the Finnish Diabetes Prevention Program, 0.4 million cases could be prevented until 2030. To prevent 1.0 million cases in 2030, 90 % of all persons with prediabetes had to take part in an intervention that reduces the transition rate from prediabetes to diabetes by 55 %. Unless enormous efforts are spent into prevention programs, the number of persons with type 2 diabetes will increase tremendously in the next two decades.

Creating public awareness: state 2025 diabetes forecasts

The incidence and prevalence of diabetes (primarily type 2 diabetes) has risen sharply since 1990. It is projected to increase another 64% between 2010 and 2025, affecting 53.1 million people and resulting in medical and societal costs of a half trillion dollars a year. We know how to prevent many cases of diabetes and how to treat it effectively. Early appropriate treatment makes a significant difference in preventing major complications and reducing premature death, but it does not cure the disease. Early detection of prediabetes, in conjunction with lifestyle changes, can reduce the number of people with diabetes. A dramatic reduction in diabetes prevalence over time will require significant lifestyle changes on the part of society as a whole. The purpose of this study is to increase public awareness of the severity of regional diabetes trends by providing detailed forecasts for all states and several metropolitan areas for 2010, 2015, and 2025. A model was created to utilize the latest national diabetes and population data and projections, and to transform these into state and metropolitan area forecasts for the whole population and major subgroups. These forecasts were then summarized in easy-to-understand briefing papers for each state and selected metro areas, which are provided online for easy public access. This research is important because little data exist that project the future prevalence and potential costs of diabetes at the state and metro area level. With this data, key stakeholders can make informed decisions concerning diabetes, its impact on their communities, and resource allocation.

American ginseng stimulates insulin production and prevents apoptosis through regulation of uncoupling protein-2 in cultured beta cells

American ginseng root displays the ability to achieve glucose homeostasis both experimentally and clinically but the unknown mechanism used by ginseng to achieve its therapeutic effects on diabetes limits its application. Disruption in the insulin secretion of pancreatic β cells is considered the major cause of diabetes. A mitochondrial protein, uncoupling protein-2 (UCP-2) has been found to play a critical role in insulin synthesis and β cell survival. Our preliminary studies found that the extracts of American ginseng inhibit UCP-2 expression which may contribute to the ability of ginseng protecting β cell death and improving insulin synthesis. Therefore, we hypothesized that ginseng extracts suppress UCP-2 in the mitochondria of pancreatic β cells, promoting insulin synthesis and anti-apoptosis (a programmed cell-death mechanism). To test the hypothesis, the serum-deprived quiescent β cells were cultured with or without interleukin-1β (IL-1β), (200 pg ml⁻¹, a cytokine to induce β cell apoptosis) and water extracts of American ginseng (25 μg per 5 μl administered to wells of 0.5 ml culture) for 24 h. We evaluated effects of ginseng on UCP-2 expression, insulin production, anti-/pro-apoptotic factors Bcl-2/caspase-9 expression and cellular ATP levels. We found that ginseng suppresses UCP-2, down-regulates caspase-9 while increasing ATP and insulin production/secretion and up-regulates Bcl-2, reducing apoptosis. These findings suggest that stimulation of insulin production and prevention of β cell loss by American ginseng extracts can occur via the inhibition of mitochondrial UCP-2, resulting in increase in the ATP level and the anti-apoptotic factor Bcl-2, while down-regulation of pro-apoptotic factor caspase-9 occurs, lowering the occurrence of apoptosis, which support the hypothesis.

Identification of barriers to appropriate dietary behavior in low-income patients with type 2 diabetes mellitus

OBJECTIVE

To identify barriers to appropriate dietary behavior in an urban, low-income population of patients with type 2 diabetes and to examine a new instrument in the identification of these barriers in this population.

METHODS

A cross-sectional survey was developed, validated, and anonymously administered to low-income adults with type 2 diabetes in an academic family medicine physician group practice with a pharmacist-operated diabetes education and comanagement service. The survey consisted of three key subscales: determinants of food selection, importance of life challenges, and barriers to appropriate eating.

RESULTS

The survey was administered to 98 patients with a mean age of 51.98 years, a mean duration of diabetes of 9.76 years, and a mean hemoglobin A1c of 7.99%. When asked to rate factors most important in food selection, the highest mean responses were taste (3.97 out of 5) and cost (score of 3.94 out of 5). Barriers that the majority of respondents agreed or strongly agreed were important included: stress causing over-eating or unhealthy food choices, difficulty resisting the temptation to eat unhealthy food, and healthy food being too expensive. The Cronbach's Alpha for the subscales of food selection, importance of life challenges, and barrier were 0.673, 0.853, and 0.786, respectively.

CONCLUSIONS

In a low-income, urban, predominantly African American and Caucasian diabetic population, cost of healthy food, stress-related inappropriate eating, and the temptation to eat unhealthy food were the most frequently reported barriers to healthy eating. Diabetes education programs serving similar populations should evaluate the presence of these barriers. The survey instrument was a reliable measure of the constructs it purported to measure.

The role of surgical debridement in healing of diabetic foot ulcers

An estimated 15% of patients with diabetes mellitus will develop a foot ulcer during their lifetime. Debridement is included in multiple guidelines and algorithms for the care of patients with diabetic neuropathic foot ulcers, and it has long been considered an essential step in the protocol for treating diabetic foot ulcers. In addition to altering the environment of the chronic wound, debridement is a technique aimed at removing nonviable and necrotic tissue, thought to be detrimental to healing. This is accomplished by removing abnormal wound bed and wound edge tissue, such as hyperkeratotic epidermis (callus) and necrotic dermal tissue, foreign debris, and bacteria elements known to have an inhibitory effect on wound healing. While the rationale for surgical debridement seems logical, the evidence for its role in enhancing healing is deficient. In this paper, we systematically review five published clinical trials, which met the criteria and investigated surgical debridement of diabetic foot ulcers to enhance healing. Most existing studies are not randomized clinical trials optimized to test the relationship between debridement of diabetic foot ulcers and wound healing. Therefore, a focused, well-designed study is needed to elucidate the effect of surgical debridement on the healing status of chronic wounds.

Mortality and morbidity trends: is there compression of morbidity?

OBJECTIVE

This paper reviews trends in mortality and morbidity to evaluate whether there has been a compression of morbidity.

METHODS

Review of recent research and analysis of recent data for the United States relating mortality change to the length of life without 1 of 4 major diseases or loss of mobility functioning.

RESULTS

Mortality declines have slowed down in the United States in recent years, especially for women. The prevalence of disease has increased. Age-specific prevalence of a number of risk factors representing physiological status has stayed relatively constant; where risks decline, increased usage of effective drugs is responsible. Mobility functioning has deteriorated. Length of life with disease and mobility functioning loss has increased between 1998 and 2008.

DISCUSSION

Empirical findings do not support recent compression of morbidity when morbidity is defined as major disease and mobility functioning loss.

Projection of the year 2050 burden of diabetes in the US adult population: dynamic modeling of incidence, mortality, and prediabetes prevalence

BACKGROUND

People with diabetes can suffer from diverse complications that seriously erode quality of life. Diabetes, costing the United States more than $174 billion per year in 2007, is expected to take an increasingly large financial toll in subsequent years. Accurate projections of diabetes burden are essential to policymakers planning for future health care needs and costs.

METHODS

Using data on prediabetes and diabetes prevalence in the United States, forecasted incidence, and current US Census projections of mortality and migration, the authors constructed a series of dynamic models employing systems of difference equations to project the future burden of diabetes among US adults. A three-state model partitions the US population into no diabetes, undiagnosed diabetes, and diagnosed diabetes. A four-state model divides the state of "no diabetes" into high-risk (prediabetes) and low-risk (normal glucose) states. A five-state model incorporates an intervention designed to prevent or delay diabetes in adults at high risk.

RESULTS

The authors project that annual diagnosed diabetes incidence (new cases) will increase from about 8 cases per 1,000 in 2008 to about 15 in 2050. Assuming low incidence and relatively high diabetes mortality, total diabetes prevalence (diagnosed and undiagnosed cases) is projected to increase from 14% in 2010 to 21% of the US adult population by 2050. However, if recent increases in diabetes incidence continue and diabetes mortality is relatively low, prevalence will increase to 33% by 2050. A middle-ground scenario projects a prevalence of 25% to 28% by 2050. Intervention can reduce, but not eliminate, increases in diabetes prevalence.

CONCLUSIONS

These projected increases are largely attributable to the aging of the US population, increasing numbers of members of higher-risk minority groups in the population, and people with diabetes living longer. Effective strategies will need to be undertaken to moderate the impact of these factors on national diabetes burden. Our analysis suggests that widespread implementation of reasonably effective preventive interventions focused on high-risk subgroups of the population can considerably reduce, but not eliminate, future increases in diabetes prevalence.

Projection of the year 2050 burden of diabetes in the US adult population: dynamic modeling of incidence, mortality, and prediabetes prevalence

Background

People with diabetes can suffer from diverse complications that seriously erode quality of life. Diabetes, costing the United States more than $174 billion per year in 2007, is expected to take an increasingly large financial toll in subsequent years. Accurate projections of diabetes burden are essential to policymakers planning for future health care needs and costs.

Methods

Using data on prediabetes and diabetes prevalence in the United States, forecasted incidence, and current US Census projections of mortality and migration, the authors constructed a series of dynamic models employing systems of difference equations to project the future burden of diabetes among US adults. A three-state model partitions the US population into no diabetes, undiagnosed diabetes, and diagnosed diabetes. A four-state model divides the state of "no diabetes" into high-risk (prediabetes) and low-risk (normal glucose) states. A five-state model incorporates an intervention designed to prevent or delay diabetes in adults at high risk.

Results

The authors project that annual diagnosed diabetes incidence (new cases) will increase from about 8 cases per 1,000 in 2008 to about 15 in 2050. Assuming low incidence and relatively high diabetes mortality, total diabetes prevalence (diagnosed and undiagnosed cases) is projected to increase from 14% in 2010 to 21% of the US adult population by 2050. However, if recent increases in diabetes incidence continue and diabetes mortality is relatively low, prevalence will increase to 33% by 2050. A middle-ground scenario projects a prevalence of 25% to 28% by 2050. Intervention can reduce, but not eliminate, increases in diabetes prevalence.

Conclusions

These projected increases are largely attributable to the aging of the US population, increasing numbers of members of higher-risk minority groups in the population, and people with diabetes living longer. Effective strategies will need to be undertaken to moderate the impact of these factors on national diabetes burden. Our analysis suggests that widespread implementation of reasonably effective preventive interventions focused on high-risk subgroups of the population can considerably reduce, but not eliminate, future increases in diabetes prevalence.

The impact of ageing and changing utilization patterns on future cardiovascular drug expenditure: a pharmacoepidemiological projection approach

PURPOSE

To develop a method for projecting the impact of ageing and changing drug utilization patterns on future drug expenditure.

METHODS

Applying nationwide registries, prescriptions of three categories of cardiovascular drugs were followed for all Danish residents from 1 January 1996 until 2006. The official Danish population forecast 2006-2015 was applied for projecting the population composition. A previously developed pharmacoepidemiological semi-Markov model was extended to apply for projection of future drug utilization. We either assumed that past trends in model parameters (incidence, discontinuation and drug user mortality) would continue during 2006-2015, or that all model parameters would remain unchanged at their values in 2005. Yearly drug expenditure per user of a particular drug was assumed to remain unchanged. Scenarios of future treatment prevalence with different drug categories were modelled by extrapolating future age- and gender-specific parameter values (treatment incidence, discontinuation and drug user mortality) from historic point estimates and their historic trend.

RESULTS

Provided a continuance of past trends, increasing utilization of ACE inhibitors, angiotensin II antagonists and statins translates into a rise in annual expenditure of 176%, mainly explained by increases in treatment incidence. Due to pharmacoepidemiological disequilibrium, unchanged model parameters would imply an increase of 64%, ageing alone 14%.

CONCLUSION

Increasing cardiovascular drug utilization may pose a substantial burden on future health care resources. However, prescribing behaviour is likely to depend on changing clinical guidelines. Despite the limited impact as cost driver, population ageing remains a challenge for future health care services.

Promotion of bone formation by naringin in a titanium particle-induced diabetic murine calvarial osteolysis model

Diabetic patients have an increased risk of prosthesis failure requiring revision surgery. Furthermore, skeletal defects are observed in conjunction with type 1 diabetes. Using a titanium particle-induced calvarial osteolysis model in diabetic mice, we investigated the effect of diabetes on the osteolytic process and the role of naringin in its prevention. Three groups each of nondiabetic or diabetic mice were treated with vehicle only, with particles only, or with particles then naringin for 10 days. Alteration of bone indices near the midline suture were then analyzed by microcomputed tomography scanning and histology. Serum levels of osteocalcin (OCN) and cross-linked N-telopeptide of type I collagen (NTx) were measured by enzyme-linked immunosorbent assay. The decreases in new bone formation (p < 0.05), calvaria thickness (p < 0.05), bone volume (p < 0.05), midline suture area (p < 0.05), and OCN concentration (p < 0.05) found in diabetic mice were normalized with naringin treatment. Diabetic state promoted particle-induced osteolysis. Naringin, an osteoanabolic agent, improved bone indices apparently by stimulating bone formation. Therefore, naringin may be beneficial in preventing and treating debris-mediated periprosthetic osteolysis after total joint replacement, especially in diabetics.

The prevention of type 2 diabetes: an overview

Type 2 diabetes mellitus is one of the major public health threats in the United States today, reaching epidemic rates. Epidemiological evidence suggests a strong link between obesity and the risk of developing diabetes. Increasing evidence demonstrates that lifestyle interventions can significantly delay or possibly prevent the onset of type 2 diabetes in persons with increased risk. Despite these findings, there remain important barriers to the translation of this research to the public health. These include identifying persons with an increased risk for developing the disease and the lack of easily accessible, cost-effective intervention programs. At least one study, however, has effectively implemented an evidenced-based intervention in community settings, suggesting that it may be possible to develop a model for the national scalability of primary prevention in the United States.

Quantifying a strategic view of diabetes technology impacts: a system dynamics approach

BACKGROUND

Diabetes and its related complications and comorbidities (C&Cs) represent a significant and increasing healthcare burden. Absence of a systematic manner to evaluate value propositions of technologies from various stakeholders' perspectives impedes the best uses of current and emerging technologies.

METHODS

A system dynamics methodology was used to develop a comprehensive causal simulator of the U.S. population and give proof of principle that entire portfolios of present and future technologies can be evaluated for direct and indirect impacts. An explicit semiquantitative methodology was used for surveying, prioritizing, and grouping C&Cs, patient subgroups, and technologies, utilizing diverse publicly available clinical literature.

RESULTS

The resulting model simulates the incidence and prevalence of diabetes and 10 of its most commonly associated C&Cs, reflecting their interrelated upstream and downstream relationships. The simulator enables systematic evaluation of tens of thousands of potential combinations of emerging technologies and technology leverage points that can be used to improve patient outcomes and guide technology investments. Feasibility was demonstrated through single, pair-wise, and targeted analyses of technologies.

CONCLUSIONS

This effort demonstrated the feasibility of linking complex, interconnected disease states, impact points, outcomes, and interventions with a variety of outcome metrics, to an extent greater than existing models developed for other purposes. The project demonstrated the ability to identify priority technologies and pipeline therapies and leverage points among diabetes interventions. It demonstrated more effective knowledge management of diverse information essential for formulating strategy that could be applied in a wide range of therapeutic applications and technology innovation uses.

Modeling transition rates using panel current-status data: how serious is the bias?

Studies of disability dynamics and active life expectancy often rely on transition rates or probabilities that are estimated using panel survey data in which respondents report on current health or functional status. If respondents are contacted at intervals of one or two years, then relatively short periods of disability or recovery between surveys may be missed. Much published research that uses such data assumes that there are no unrecorded transitions, applying event-history techniques to estimate transition rates. In recent years, a different approach based on embedded Markov chains has received growing use. We assessed the performance of both approaches, using as a criterion their ability to reproduce the parameters of a "true" model based on panel data collected at one-month intervals. Neither of the widely used approaches performs particularly well, and neither is uniformly superior to the other.

Monitoring progress toward CDC's health protection goals: health outcome measures by life stage

OBJECTIVES

From 2004 through 2005, as part of a major strategic planning process called the Futures Initiative, the Centers for Disease Control and Prevention (CDC) developed a set of Health Protection Goals to make the best use of agency resources to achieve health impact. These goals were framed in terms of people, places, preparedness, and global health. This article presents a goals framework and a set of health outcome measures with historical trends and forecasts to track progress toward the Healthy People goals by life stage (Infants and Toddlers, Children, Adolescents, Adults, and Older Adults and Seniors).

METHODS

Measurable key health outcomes were chosen for each life stage to capture the multidimensional aspects of health, including mortality, morbidity, perceived health, and lifestyle factors. Analytic methods involved identifying nationally representative data sources, reviewing 20-year trends generally ranging from 1984 through 2005, and using time-series techniques to forecast measures by life stage until 2015.

RESULTS

Improvements in measures of mortality and morbidity were noted among all life stages during the study period except Adults, who reported continued declining trends in perceived health status. Although certain behavioral indicators (e.g., prevalence of nonsmokers) revealed steady improvements among Adolescents, Adults, and Older Adults and Seniors, prevalence of the healthy weight indicator was declining steadily among Children and Adolescents and dramatically among Adults and Older Adults and Seniors.

CONCLUSION

The health indicators for the Healthy People goals established a baseline assessment of population health, which will be monitored on an ongoing basis to measure progress in maximizing health and achieving one component of CDC's Health Protection Goals.

Reductions in excess mortality rates among people with diabetes by selected cause of death

We applied Bayesian methods to estimate excess mortality rates by selected causes of death for decedents with diabetes compared to those without diabetes in North Dakota and assessed changes in the excess rate between 1992-1998 and 1999-2003. We report the probability (Pr) of a rate decrease in the age-adjusted excess rate and considered the evidence strong if the probability was 0.90 or higher. Among men with diabetes, the evidence was strong for a probable decrease in excess rate for heart disease (8.7 per 1000 to 6.5), cerebrovascular disease (1.2 per 1000 to 0.75) and arterial disease (0.24 per 1000 to 0.08). Among women with diabetes, the evidence was strong for a probable decrease in excess rates for the overall (total) rate (17.8 per 1000 to 12.6), for heart disease (6.1 per 1000 to 4.4), IHD (4.4 per 1000 to 3.1), cerebrovascular disease (1.4 per 1000 to 0.5), arterial disease (0.17 per 1000 to 0.10) and cancer (2.1 per 1000 to 1.3) as underlying cause of death. The data reflect a high likelihood that cause-specific excess mortality is decreasing for men, and especially for women, with diabetes.

Maintaining a physiological blood glucose level with 'glucolevel', a combination of four anti-diabetes plants used in the traditional arab herbal medicine

Safety and anti-diabetic effects of Glucolevel, a mixture of dry extract of leaves of the Juglans regia L, Olea europea L, Urtica dioica L and Atriplex halimus L were evaluated using in vivo and in vitro test systems. No sign of toxic effects (using LDH assay) were seen in cultured human fibroblasts treated with increasing concentrations of Glucolevel. Similar observations were seen in vivo studies using rats (LD50: 25 g/kg). Anti-diabetic effects were evidenced by the augmentation of glucose uptake by yeast cells (2-folds higher) and by inhibition of glucose intestinal absorption ( approximately 49%) in a rat gut-segment. Furthermore, treatment with Glucolevel of Streptozotocin-induced diabetic rats for 2-3 weeks showed a significant reduction in glucose levels [above 400 +/- 50 mg/dl to 210 +/- 22 mg/dl (P < 0.001)] and significantly improved sugar uptake during the glucose tolerance test, compared with positive control. In addition, glucose levels were tested in sixteen human volunteers, with the recent onset of type 2 diabetes mellitus, who received Glucolevel tablets 1 x 3 daily for a period of 4 weeks. Within the first week of Glucolevel consumption, baseline glucose levels were significantly reduced from 290 +/- 40 to 210 +/- 20 mg/dl. At baseline, a subgroup of eleven of these subjects had glucose levels below 300 mg% and the other subgroup had levels >/= 300 mg%. Clinically acceptable glucose levels were achieved during the 2-3 weeks of therapy in the former subgroup and during the 4th week of therapy in the latter subgroup. No side effect was reported. In addition, a significant reduction in hemoglobin A1C values (8.2 +/- 1.03 to 6.9 +/- 0.94) was found in six patients treated with Glucolevel. Results demonstrate safety, tolerability and efficacy of herbal combinations of four plants that seem to act differently but synergistically to regulate glucose-homeostasis.

Epidemiology of diabetes and diabetes-related complications

In 2005, it was estimated that more than 20 million people in the United States had diabetes. Approximately 30% of these people had undiagnosed cases. Increased risk for diabetes is primarily associated with age, ethnicity, family history of diabetes, smoking, obesity, and physical inactivity. Diabetes-related complications--including cardiovascular disease, kidney disease, neuropathy, blindness, and lower-extremity amputation--are a significant cause of increased morbidity and mortality among people with diabetes, and result in a heavy economic burden on the US health care system. With advances in treatment for diabetes and its associated complications, people with diabetes are living longer with their condition. This longer life span will contribute to further increases in the morbidity associated with diabetes, primarily in elderly people and in minority racial or ethnic groups. In 2050, the number of people in the United States with diagnosed diabetes is estimated to grow to 48.3 million.

RESULTS

from randomized controlled trials provide evidence that intensive lifestyle interventions can prevent or delay the onset of diabetes in high-risk individuals. In addition, adequate and sustained control of blood sugar levels, blood pressure, and blood lipid levels can prevent or delay the onset of diabetes-related complications in people with diabetes. Effective interventions, at both the individual and population levels, are desperately needed to slow the diabetes epidemic and reduce diabetes-related complications in the United States. This report describes the current diabetes epidemic and the health and economic impact of diabetes complications on individuals and on the health care system. The report also provides suggestions by which the epidemic can be curbed.

Association between renal failure and foot ulcer or lower-extremity amputation in patients with diabetes

OBJECTIVE

The objective of this study was to evaluate the association between foot ulcers (DFU) and lower-extremity amputation (LEA) and chronic kidney disease (CKD) in patients with diabetes. RESARCH DESIGN AND METHODS: This was a retrospective cohort study of individuals enrolled between 2002 and 2006 who were aged > or =35 years, had a history of diabetes, and were cared for in general practice. The physicians participated in The Health Information Network of the U.K.

RESULTS

The presence of DFU or LEA and estimated glomerular filtration rate (eGFR) were evaluated in 90,617 individuals with a median time of observation of 2.4 years. Of these individuals 378 had an LEA and 2,619 had a DFU. CKD (eGFR <60 ml/min per 1.73 m(2)) was noted in 23,350 (26%) individuals in our cohort. For the development of DFU compared with our reference group (group 1 [eGFR > or =60 ml/min per 1.73 m(2)]), the hazard ratio (HR) for group 2 (eGFR > or =30 and <60 ml/min per 1.73 m(2)) was 1.85 (95% CI 1.71-2.01) and for group 3 (eGFR <30 ml/min per 1.73 m(2)) was 3.92 (3.23-4.75) (all P < 0.001). For LEA, the HR for group 2 was 2.08 (1.68-2.58) and for group 3 was 7.71 (5.29-11.26) (all P < 0.001).

CONCLUSIONS

In this observational study, there is a strong association between stage of CKD and DFU or LEA that is probably not just related to the presence of peripheral arterial disease. Individuals with even moderate CKD (eGFR <60 ml/min per 1.73 m(2)) have an increased risk for DFU and LEA.

Impact of therapeutic advances on hypoglycaemia in type 2 diabetes

Patients with type 2 diabetes experience hypoglycaemia less frequently than those with type 1 diabetes. Some protection against hypoglycaemia is afforded by the relatively intact glucose counter-regulatory pathways that characterize the pathophysiology of early type 2 diabetes. To some extent, this protection explains why hypoglycaemic episodes in intensively treated individuals with type 2 diabetes, when they occur, are rarely severe. As diabetes progresses and therapy intensifies to achieve recommended glycaemic goals, hypoglycaemia frequency and severity increase. Thus, when it comes to instituting intensive therapy, fear of hypoglycaemia may contribute to health-care providers' 'clinical inertia'. Because maintaining glycaemic control is so important to both public and individual health, many new therapies and technologies have been developed. This manuscript reviews and considers whether these advancements in therapy make glycaemic goals easier to achieve by minimizing hypoglycaemia. Putting the hypoglycaemia experienced by type 2 diabetes patients into appropriate clinical perspective, the impact of recent progress made in pharmacotherapy, drug delivery systems, and BG monitoring on hypoglycaemia incidence is largely positive. The extent to which this progress can effect improvement over traditional therapies will, however, depend upon patient (and provider) education, motivation and behaviour change.