Age at initiation and frequency of screening to detect type 2 diabetes: a cost-effectiveness analysis

Diabetes screening among immigrants: a population-based urban cohort study

OBJECTIVE

To examine diabetes screening, predictors of screening, and the burden of undiagnosed diabetes in the immigrant population and whether these estimates differ by ethnicity.

RESEARCH DESIGN AND METHODS

A population-based retrospective cohort linking administrative health data to immigration files was used to follow the entire diabetes-free population aged 40 years and up in Ontario, Canada (N = 3,484,222) for 3 years (2004-2007) to determine whether individuals were screened for diabetes. Multivariate regression was used to determine predictors of having a diabetes test.

RESULTS

Screening rates were slightly higher in the immigrant versus the general population (76.0 and 74.4%, respectively; P < 0.001), with the highest rates in people born in South Asia, Mexico, Latin America, and the Caribbean. Immigrant seniors (age ≥65 years) were screened less than nonimmigrant seniors. Percent yield of new diabetes subjects among those screened was high for certain countries of birth (South Asia, 13.0%; Mexico and Latin America, 12.1%; Caribbean, 9.5%) and low among others (Europe, Central Asia, U.S., 5.1-5.2%). The number of physician visits was the single most important predictor of screening, and many high-risk ethnic groups required numerous visits before a test was administered. The proportion of diabetes that remained undiagnosed was estimated to be 9.7% in the general population and 9.0% in immigrants.

CONCLUSIONS

Overall diabetes-screening rates are high in Canada's universal health care setting, including among high-risk ethnic groups. Despite this finding, disparities in screening rates between immigrant subgroups persist and multiple physician visits are often required to achieve recommended screening levels.

Detection of impaired glucose regulation and/or type 2 diabetes mellitus, using primary care electronic data, in a multiethnic UK community setting

AIMS/HYPOTHESIS

The aim of this study was to develop and validate a score for detecting the glycaemic categories of impaired glucose regulation (IGR) and type 2 diabetes using the WHO 2011 diagnostic criteria.

METHODS

We used data from 6,390 individuals aged 40-75 years from a multiethnic population based screening study. We developed a logistic regression model for predicting IGR and type 2 diabetes (diagnosed using OGTT or HbA(1c) ≥ 6.5% [48 mmol/mol]) from data which are routinely stored in primary care. We developed the score by summing the β coefficients. We externally validated the score using data from 3,225 participants aged 40-75 years screened as part of another study.

RESULTS

The score includes age, ethnicity, sex, family history of diabetes, antihypertensive therapy and BMI. Fifty per cent of a population would need to be invited for testing to detect type 2 diabetes mellitus on OGTT with 80% sensitivity; this is slightly raised to 54% that need to be invited if using HbA(1c). Inviting the top 10% for testing, 9% of these would have type 2 diabetes mellitus using an OGTT (positive predictive value [PPV] 8.9% [95% CI 5.8%,12.8%]), 26% would have IGR (PPV 25.9% [95% CI 20.9%, 31.4%]). Using HbA(1c) increases the PPV to 19% for type 2 diabetes mellitus (PPV 18.6% [95% CI 14.2%, 23.7%]) and 28% for an HbA(1c) between 6.0% and 6.4% (PPV 28.3% [95% CI 23.1%, 34.0%]).

CONCLUSIONS

The score can be used to reliably identify those with undiagnosed IGR and type 2 diabetes in multiethnic populations. This is the first score developed taking into account HbA(1c) in the diagnosis of type 2 diabetes.

A globally applicable screening model for detecting individuals with undiagnosed diabetes

AIMS

Current risk scores for undiagnosed diabetes are additive in structure. We sought to derive a globally applicable screening model based on established non-invasive risk factors for diabetes but with a more flexible structure.

METHODS

Data from the DETECT-2 study were used, including 102,058 participants from 38 studies covering 8 geographical regions worldwide. A global screening model for undiagnosed diabetes was identified through tree-structured regression analysis. The performance of the global screening model was evaluated in each of the geographical regions by receiver operating characteristic (ROC) analysis.

RESULTS

The global screening model included age, height, body mass index, waist circumference and systolic- and diastolic blood pressure. Area under the ROC curve ranged between 0.64 in North America and 0.76 in Australia and New Zealand. Overall, to identify 75% of the undiagnosed diabetes cases, 49% required further diagnostic testing.

CONCLUSIONS

We identified a globally applicable screening model to detect individuals at high risk of undiagnosed diabetes. The model performed well in most geographical regions, is simple and requires no calculations. This global screening model may be particularly helpful in developing countries with no population based data with which to develop own screening models.

Prevalence, awareness and treatment of type 2 diabetes mellitus in Switzerland: the CoLaus study

AIMS

To assess the prevalence, awareness and treatment levels of Type 2 diabetes in a Swiss city.

METHODS

Population-based cross-sectional study of 6181 subjects (3246 women) aged 35-75 years living in Lausanne, Switzerland. Type 2 diabetes was defined as fasting plasma glucose ≥ 7 mmol/l and/or oral hypoglycaemic treatment and/or insulin.

RESULTS

Total prevalence of Type 2 diabetes was 6.3% (95% confidence interval: 5.7-7.0%), higher in men (9.1%) than in women (3.8%, P < 0.001) and increased with age. Two-thirds (65.3%; 60.4-70.0%) of participants with Type 2 diabetes were aware of their status and among those aware 86.0% (81.5-90.3%) were treated. Treatment was more frequent in men (91.3%) than in women (75.9%, P < 0.001). Two-thirds of those treated for Type 2 diabetes were on monotherapy. Biguanides were prescribed in 65.0% of Type 2 diabetes patients and represented 48% of all antidiabetic drugs. Multivariable analysis showed male gender, increasing age, waist or BMI to be positively associated with prevalence of Type 2 diabetes, while leisure-time physical activity and alcohol consumption were negatively associated. Among participants presenting with Type 2 diabetes, increasing age was positively associated with awareness of Type 2 diabetes. Among subjects diagnosed with Type 2 diabetes, male gender and increasing age were positively associated with treatment.

CONCLUSION

Prevalence of Type 2 diabetes in Switzerland is estimated to be between 5.7% and 7.0%. Two-thirds of patients with Type 2 diabetes are aware of their status, and over three quarters of those aware are treated.

Integrated management of type 2 diabetes mellitus and depression treatment to improve medication adherence: a randomized controlled trial

PURPOSE

Depression commonly accompanies diabetes, resulting in reduced adherence to medications and increased risk for morbidity and mortality. The objective of this study was to examine whether a simple, brief integrated approach to depression and type 2 diabetes mellitus (type 2 diabetes) treatment improved adherence to oral hypoglycemic agents and antidepressant medications, glycemic control, and depression among primary care patients.

METHODS

We undertook a randomized controlled trial conducted from April 2010 through April 2011 of 180 patients prescribed pharmacotherapy for type 2 diabetes and depression in primary care. Patients were randomly assigned to an integrated care intervention or usual care. Integrated care managers collaborated with physicians to offer education and guideline-based treatment recommendations and to monitor adherence and clinical status. Adherence was assessed using the Medication Event Monitoring System (MEMS). We used glycated hemoglobin (HbA(1c)) assays to measure glycemic control and the 9-item Patient Health Questionnaire (PHQ-9) to assess depression.

RESULTS

Intervention and usual care groups did not differ statistically on baseline measures. Patients who received the intervention were more likely to achieve HbA(1c) levels of less than 7% (intervention 60.9% vs. usual care 35.7%; P < .001) and remission of depression (PHQ-9 score of less than 5: intervention 58.7% vs. usual care 30.7%; P < .001) in comparison with patients in the usual care group at 12 weeks.

CONCLUSIONS

A randomized controlled trial of a simple, brief intervention integrating treatment of type 2 diabetes and depression was successful in improving outcomes in primary care. An integrated approach to depression and type 2 diabetes treatment may facilitate its deployment in real-world practices with competing demands for limited resources.

Developmental origins of noncommunicable disease: population and public health implications

Noncommunicable diseases (NCDs), including cardiovascular disease, diabetes, chronic lung disease, allergy, some forms of cancer, cognitive decline, osteoporosis, sarcopenia, and affective disorders, are the world's biggest killers. Eighty percent of these deaths occur in low- and middle-income countries, especially as these countries undergo socioeconomic improvement after reductions in infectious disease. The World Health Organization predicts a global increase of 17% in NCDs over the next decade. NCDs are preventable, but new initiatives are needed to institute such prevention, especially in early life. In this article, we emphasize that all children are affected by their early developmental conditions, not just children exposed to a very deficient environment, and that this has long-term consequences for their predisposition to NCDs. We highlight the biomedical implications of this developmental origins of health and disease (DOHaD) concept of NCDs and discuss the implications for health policy.

Screening for type 2 diabetes. Lessons from the ADDITION-Europe study

AIMS

To describe and compare attendance rates and the proportions of people identified with Type 2 diabetes mellitus in people with previously unknown diabetes who participated in screening programmes undertaken in general practice in the UK, Denmark and the Netherlands as part of the ADDITION-Europe study.

METHODS

In Cambridge, routine computer data searches were conducted to identify individuals aged 40-69 years at high risk of Type 2 diabetes using the Cambridge Diabetes Risk Score. In Denmark, the Danish Diabetes Risk Score was mailed to individuals aged 40-69 years, or completed by patients visiting their general practitice. In the Netherlands, the Hoorn Symptom Risk Questionnaire was mailed to individuals aged 50-69 years. In these three centres, high-risk individuals were invited to attend subsequent steps in the screening programme, including random blood glucose, HbA(1c) , fasting blood glucose and/or oral glucose tolerance test. In Leicester, eligible people aged 40-69 years were invited directly for an oral glucose tolerance test. In all centres, Type 2 diabetes was defined according to World Health Organization 1999 diagnostic criteria.

RESULTS

Attendance rates ranged from 20.2% (oral glucose tolerance test in Leicester without pre-stratification) to 95.1% (random blood glucose in opportunistic screening in Denmark in high-risk people). The percentage of people with newly detected Type 2 diabetes from the target population ranged from 0.33% (Leicester) to 1.09% (the Netherlands).

CONCLUSIONS

Screening for Type 2 diabetes was acceptable and feasible, but relatively few participants were diagnosed in all participating centres. Different strategies may be required to increase initial attendance and ensure completion of screening programmes.

Prediabetes: to treat or not to treat?

The incidence of diabetes is continuously increasing worldwide. Pre-diabetes (defined as impaired glucose tolerance, impaired fasting glucose or both) represents an intermediate state, which often progresses to overt diabetes within a few years. In addition, pre-diabetes may be associated with increased risk of microvascular and macrovascular complications. Thus, reverting a pre-diabetic state as well as preventing the development of diabetes represents enormous challenge for the clinician. Lifestyle modification in pre-diabetic individuals was found particularly effective in the prevention of diabetes. However, compliance to lifestyle modification measures can be a crucial problem in the everyday clinical practice, especially in developing countries. During the last decade many studies support the use of anti-diabetic treatment schemes in pre-diabetic subjects to be advantageous. The American Diabetes Prevention Program (DPP) as well as other minor studies and meta-analyses has convincingly demonstrated the efficacy of metformin in this patient group. In addition, results of the 10 year DPP follow up have recently been published, demonstrating the long term safety and sustainability of metformin treatment benefits in this population. In contrast to metformin, the evidence from the use of other anti-diabetic agents (thiazolidinediones, a-glucosidase inhibitors, incretin mimetics) in pre-diabetic individuals is rather inadequate and prospective data is further needed. Furthermore, large scale studies with hard clinical endpoints are needed to delineate the effect of pre-diabetes treatment on macro- and microvascular complications. In conclusion, several strategies of patient management, mainly lifestyle modification and pharmacological interventions can prevent diabetes development in subjects diagnosed with pre-diabetes or even revert pre-diabetic state. However, whether this biochemical improvement can be translated into actual clinical benefit remains to be established.

Value of primordial and primary prevention for cardiovascular disease: a policy statement from the American Heart Association

The process of atherosclerosis may begin in youth and continue for decades, leading to both nonfatal and fatal cardiovascular events, including myocardial infarction, stroke, and sudden death. With primordial and primary prevention, cardiovascular disease is largely preventable. Clinical trial evidence has shown convincingly that pharmacological treatment of risk factors can prevent events. The data are less definitive but also highly suggestive that appropriate public policy and lifestyle interventions aimed at eliminating tobacco use, limiting salt consumption, encouraging physical exercise, and improving diet can prevent events. There has been concern about whether efforts aimed at primordial and primary prevention provide value (ie, whether such interventions are worth what we pay for them). Although questions about the value of therapeutics for acute disease may be addressed by cost-effectiveness analysis, the long time frames involved in evaluating preventive interventions make cost-effectiveness analysis difficult and necessarily flawed. Nonetheless, cost-effectiveness analyses reviewed in this policy statement largely suggest that public policy, community efforts, and pharmacological intervention are all likely to be cost-effective and often cost saving compared with common benchmarks. The high direct medical care and indirect costs of cardiovascular disease-approaching $450 billion a year in 2010 and projected to rise to over $1 trillion a year by 2030-make this a critical medical and societal issue. Prevention of cardiovascular disease will also provide great value in developing a healthier, more productive society.

Effect of early intensive multifactorial therapy on 5-year cardiovascular outcomes in individuals with type 2 diabetes detected by screening (ADDITION-Europe): a cluster-randomised trial

BACKGROUND

Intensive treatment of multiple cardiovascular risk factors can halve mortality among people with established type 2 diabetes. We investigated the effect of early multifactorial treatment after diagnosis by screening.

METHODS

In a pragmatic, cluster-randomised, parallel-group trial done in Denmark, the Netherlands, and the UK, 343 general practices were randomly assigned screening of registered patients aged 40-69 years without known diabetes followed by routine care of diabetes or screening followed by intensive treatment of multiple risk factors. The primary endpoint was first cardiovascular event, including cardiovascular mortality and morbidity, revascularisation, and non-traumatic amputation within 5 years. Patients and staff assessing outcomes were unaware of the practice's study group assignment. Analysis was done by intention to treat. This study is registered with ClinicalTrials.gov, number NCT00237549.

FINDINGS

Primary endpoint data were available for 3055 (99·9%) of 3057 screen-detected patients. The mean age was 60·3 (SD 6·9) years and the mean duration of follow-up was 5·3 (SD 1·6) years. Improvements in cardiovascular risk factors (HbA(1c) and cholesterol concentrations and blood pressure) were slightly but significantly better in the intensive treatment group. The incidence of first cardiovascular event was 7·2% (13·5 per 1000 person-years) in the intensive treatment group and 8·5% (15·9 per 1000 person-years) in the routine care group (hazard ratio 0·83, 95% CI 0·65-1·05), and of all-cause mortality 6·2% (11·6 per 1000 person-years) and 6·7% (12·5 per 1000 person-years; 0·91, 0·69-1·21), respectively.

INTERPRETATION

An intervention to promote early intensive management of patients with type 2 diabetes was associated with a small, non-significant reduction in the incidence of cardiovascular events and death.

FUNDING

National Health Service Denmark, Danish Council for Strategic Research, Danish Research Foundation for General Practice, Danish Centre for Evaluation and Health Technology Assessment, Danish National Board of Health, Danish Medical Research Council, Aarhus University Research Foundation, Wellcome Trust, UK Medical Research Council, UK NIHR Health Technology Assessment Programme, UK National Health Service R&D, UK National Institute for Health Research, Julius Center for Health Sciences and Primary Care, University Medical Center, Utrecht, Novo Nordisk, Astra, Pfizer, GlaxoSmithKline, Servier, HemoCue, Merck.

Overview of screening: where we are and where we may be headed

This volume of Epidemiologic Reviews continues a discussion about screening within the evidence community that has been going on for many years. From various perspectives, the authors of these reviews consider the benefits and harms of screening for multiple conditions; the balance between benefits and harms (and costs) is often not clear. With few exceptions, the contribution of screening to improving the health of the public is small, yet it has become a popular and growing form of prevention. It may be that we are learning that the magnitude of benefit from screening is less than we hoped, and the harms may be greater than we thought. Perhaps we should not think of screening as our primary prevention strategy but rather use screening to make a real, but limited contribution to population health for a few conditions. We might target screening to smaller subpopulations with the highest potential benefit and the lowest potential harm. The payoff for population health could be greater if we shifted some resources we now devote to screening to developing, testing, and implementing alternative approaches to preventing the important threats to population health. There needs to be a wider discussion about these issues with the public.

HbA1c and cardiovascular risk score identify people who may benefit from preventive interventions: a 7 year follow-up of a high-risk screening programme for diabetes in primary care (ADDITION), Denmark

AIMS/HYPOTHESIS

The measurement of HbA(1c) is suggested as a diagnostic test for diabetes. Screening for diabetes also identifies individuals with elevated cardiovascular risk but who are free of diabetes. This study aims to assess whether screening by HbA(1c) or glucose measures alone, or in combination with a cardiovascular risk assessment, identifies people who may benefit from preventive interventions, i.e. people with screen detected diabetes and people belonging to groups with excess mortality, during a median follow-up of 7 years.

METHODS

A population-based, stepwise high-risk screening programme was performed in 193 family practices from 2001 to 2006. Individuals aged between 40 and 69 years (N = 163,185) were sent a diabetes risk questionnaire. Of these, 20,916 people at risk of diabetes were stratified by glucose measures (normal glucose tolerance [NGT], impaired fasting glucose [IFG], impaired glucose tolerance [IGT] and diabetes), HbA(1c) (<6%; 6.0-6.4%; or ≥ 6.5%) and cardiovascular risk (heart SCORE <5 or ≥ 5). People were followed for a median of 7 years or until death. Excess mortality was calculated using the Cox hazard ratio (HR).

RESULTS

SCORE ≥ 5 identified 91.7% (95% CI 91.1-92.3%) of those who might benefit from preventive interventions. SCORE ≥ 5 in combination with HbA(1c) ≥ 6.0% identified 96.7% (95% CI 96.3-97.0%), compared with 97.6% (95%CI 97.2-97.9%) in combination with glucose measures. Glucose measures or HbA(1c) alone identified 26.1% (95% CI 25.2-27.0%) and 19.8% (95% CI 19.0-20.6%), respectively.

CONCLUSION/INTERPRETATION

In a population-based high risk screening programme in primary care, HbA(1c) ≥ 6.0% combined with an elevated cardiovascular risk assessment (SCORE ≥ 5) can feasibly be used to identify those who may benefit from preventive lifestyle intervention and/or polypharmacy.

TRIAL REGISTRATION

ClinicalTrials.gov NCT 00237549.

FUNDING

The study received unrestricted grants from Novo Nordisk, Novo Nordisk Scandinavia, Astra Denmark, Pfizer Denmark, GlaxoSmithKline Pharma Denmark, Servier Denmark and HemoCue Denmark.

Guidelines and recommendations for laboratory analysis in the diagnosis and management of diabetes mellitus

BACKGROUND

Multiple laboratory tests are used to diagnose and manage patients with diabetes mellitus. The quality of the scientific evidence supporting the use of these tests varies substantially.

APPROACH

An expert committee compiled evidence-based recommendations for the use of laboratory testing for patients with diabetes. A new system was developed to grade the overall quality of the evidence and the strength of the recommendations. Draft guidelines were posted on the Internet and presented at the 2007 Arnold O. Beckman Conference. The document was modified in response to oral and written comments, and a revised draft was posted in 2010 and again modified in response to written comments. The National Academy of Clinical Biochemistry and the Evidence-Based Laboratory Medicine Committee of the American Association for Clinical Chemistry jointly reviewed the guidelines, which were accepted after revisions by the Professional Practice Committee and subsequently approved by the Executive Committee of the American Diabetes Association.

CONTENT

In addition to long-standing criteria based on measurement of plasma glucose, diabetes can be diagnosed by demonstrating increased blood hemoglobin A(1c) (HbA(1c)) concentrations. Monitoring of glycemic control is performed by self-monitoring of plasma or blood glucose with meters and by laboratory analysis of HbA(1c). The potential roles of noninvasive glucose monitoring, genetic testing, and measurement of autoantibodies, urine albumin, insulin, proinsulin, C-peptide, and other analytes are addressed.

SUMMARY

The guidelines provide specific recommendations that are based on published data or derived from expert consensus. Several analytes have minimal clinical value at present, and their measurement is not recommended.

Screening for type 2 diabetes and dysglycemia

Type 2 diabetes mellitus (T2DM) and dysglycemia (impaired glucose tolerance and/or impaired fasting glucose) are increasingly contributing to the global burden of diseases. The authors reviewed the published literature to critically evaluate the evidence on screening for both conditions and to identify the gaps in current understanding. Acceptable, relatively simple, and accurate tools can be used to screen for both T2DM and dysglycemia. Lifestyle modification and/or medication (e.g., metformin) are cost-effective in reducing the incidence of T2DM. However, their application is not yet routine practice. It is unclear whether diabetes-prevention strategies, which influence cardiovascular risk favorably, will also prevent diabetic vascular complications. Cardioprotective therapies, which are cost-effective in preventing complications in conventionally diagnosed T2DM, can be used in screen-detected diabetes, but the magnitude of their effects is unknown. Economic modeling suggests that screening for both T2DM and dysglycemia may be cost-effective, although empirical data on tangible benefits in preventing complications or death are lacking. Screening for T2DM is psychologically unharmful, but the specific impact of attributing the label of dysglycemia remains uncertain. Addressing these gaps will inform the development of a screening policy for T2DM and dysglycemia within a holistic diabetes prevention and control framework combining secondary and high-risk primary prevention strategies.

Guidelines and recommendations for laboratory analysis in the diagnosis and management of diabetes mellitus

BACKGROUND

Multiple laboratory tests are used to diagnose and manage patients with diabetes mellitus. The quality of the scientific evidence supporting the use of these tests varies substantially.

APPROACH

An expert committee compiled evidence-based recommendations for the use of laboratory testing for patients with diabetes. A new system was developed to grade the overall quality of the evidence and the strength of the recommendations. Draft guidelines were posted on the Internet and presented at the 2007 Arnold O. Beckman Conference. The document was modified in response to oral and written comments, and a revised draft was posted in 2010 and again modified in response to written comments. The National Academy of Clinical Biochemistry and the Evidence Based Laboratory Medicine Committee of the AACC jointly reviewed the guidelines, which were accepted after revisions by the Professional Practice Committee and subsequently approved by the Executive Committee of the American Diabetes Association.

CONTENT

In addition to long-standing criteria based on measurement of plasma glucose, diabetes can be diagnosed by demonstrating increased blood hemoglobin A(1c) (Hb A(1c)) concentrations. Monitoring of glycemic control is performed by self-monitoring of plasma or blood glucose with meters and by laboratory analysis of Hb A(1c). The potential roles of noninvasive glucose monitoring, genetic testing, and measurement of autoantibodies, urine albumin, insulin, proinsulin, C-peptide, and other analytes are addressed.

SUMMARY

The guidelines provide specific recommendations that are based on published data or derived from expert consensus. Several analytes have minimal clinical value at present, and their measurement is not recommended.

Are we really active in the prevention of obesity and type 2 diabetes at the community level?

The prevalence of type 2 diabetes is increasing rapidly worldwide. Much of this increase in type 2 diabetes epidemic is related to the increase in obesity. There is now firm evidence from randomised trials that type 2 diabetes is preventable by lifestyle modification influencing diet, physical activity and obesity. This prevention effect is sustainable for many years after cessation of active intervention. The slow progression in the development and implementation of population-based strategies in the prevention of obesity and its most common and serious co-morbidity, type 2 diabetes, is of great concern. We summarise published implementation programmes and describe briefly the activities carried out in Finland. In the Finnish implementation programme for the prevention of type 2 diabetes (FIN-D2D), it was found that it is possible to prevent type 2 diabetes "in real life" in the primary health-care settings. We point out that innovative strategic guidelines and their proper implementation are needed to prevent the diabetes epidemic. Among the different tools, also taxation and other regulation to promote healthy food selection and good interaction with the media should be considered.

Treatment recommendations for prediabetes

A variety of definitions and diagnostic cutpoints have been promulgated for prediabetes without universal agreement. Professional organizations agree that current scientific evidence justifies intervention in high-risk populations for the delay or prevention of progression to diabetes. Lifestyle intervention is universally accepted as the primary intervention strategy. Secondary intervention is advocated in high-risk individuals or in the absence of a clinical response to lifestyle modification.

Knowledge-driven approaches for the guidance of first-in-children dosing

Pediatric pharmacokinetic and pediatric safety and efficacy studies are, in most cases, a mandatory activity during the drug development process in North America and Europe. Pharmacokinetic modeling in anticipation of the pediatric clinical trial should take a data or knowledge-driven approach by employing either top-down or bottom-up approaches to assessing differential age-related dosing. These two approaches depend on different starting information and are likely to be used in conjunction with each other for the purposes of defining pediatric dosing guidelines. This review primarily focuses on the available bottom-up, mechanistic models for predicting age-dependent drug absorption, distribution and elimination, and their integration through the whole-body physiologically based pharmacokinetic (PBPK) model. The bottom-up approach incorporating adult and pediatric whole-body PBPK models for optimizing age-related dosing is detailed for a drug currently undergoing pediatric development.

Preventing breast cancer in women with schizophrenia

OBJECTIVE

To record risk factors for breast cancer in women with schizophrenia and recommend preventive actions.

METHOD

A PubMed literature search (from 2005 to 2010) was conducted, using the search terms 'schizophrenia', 'antipsychotics', 'breast cancer' and 'risk factors'.

RESULTS

Several risk factors of relevance to schizophrenia were identified: obesity, elevated prolactin levels, low participation in mammography screening, high prevalence of diabetes, comparatively low parity, low incidence of breastfeeding, social disadvantage, high levels of smoking and alcohol consumption, low activity levels.

CONCLUSION

Awareness of breast cancer risk should lead to more accurate risk ascertainment, stronger linkage with primary care, regular monitoring and screening, judicious choice and low dose of antipsychotic treatment, concomitant use of adjunctive cognitive and psychosocial therapies, referral to diet and exercise programmes as well as smoking and drinking cessation programmes, avoidance of hormonal treatment and discussion with patient and family about the pros and cons of preventive measures in high-risk women. Psychiatrists are in a position to reverse many of the identified risk factors.

Impact and cost of a 2-week community-based screening and awareness program for diabetes and cardiovascular risk factors in a Swiss canton

BACKGROUND

Community-based diabetes screening programs can help sensitize the population and identify new cases. However, the impact of such programs is rarely assessed in high-income countries, where concurrent health information and screening opportunities are common place.

INTERVENTION AND METHODS

A 2-week screening and awareness campaign was organized as part of a new diabetes program in the canton of Vaud (population of 697,000) in Switzerland. Screening was performed without appointment in 190 out of 244 pharmacies in the canton at the subsidized cost of 10 Swiss Francs per participant. Screening included questions on risk behaviors, measurement of body mass index, blood pressure, blood cholesterol, random blood glucose (RBG), and A1c if RBG was ≥7.0 mmol/L. A mass media campaign promoting physical activity and a healthy diet was channeled through several media, eg, 165 spots on radio, billboards in 250 public places, flyers in 360 public transport vehicles, and a dozen articles in several newspapers. A telephone survey in a representative sample of the population of the canton was performed after the campaign to evaluate the program.

RESULTS

A total of 4222 participants (0.76% of all persons aged ≥18 years) underwent the screening program (median age: 53 years, 63% females). Among participants not treated for diabetes, 3.7% had RBG ≥ 7.8 mmol/L and 1.8% had both RBG ≥ 7.0 mmol/L and A1c ≥ 6.5. Untreated blood pressure ≥140/90 mmHg and/or untreated cholesterol ≥5.2 mmol/L were found in 50.5% of participants. One or several treated or untreated modifiable risk factors were found in 78% of participants. The telephone survey showed that 53% of all adults in the canton were sensitized by the campaign. Excluding fees paid by the participants, the program incurred a cost of CHF 330,600.

CONCLUSION

A community-based screening program had low efficiency for detecting new cases of diabetes, but it identified large numbers of persons with elevated other cardiovascular risk factors. Our findings suggest the convenience of A1c for mass screening of diabetes, the usefulness of extending diabetes screening to other cardiovascular risk factors, and the importance of a robust background communication campaign.

Modeling the effects of omalizumab over 5 years among patients with moderate-to-severe persistent allergic asthma

OBJECTIVE

Omalizumab is a monoclonal antibody indicated for adults and adolescents with moderate-to-severe persistent allergic asthma whose symptoms are inadequately controlled with inhaled corticosteroids. Omalizumab has been demonstrated to improve health outcomes of asthmatic patients as compared to placebo. However, to date, the trials conducted have been relatively short (less than 1 year) and have been restricted to a limited set of patients who met the clinical study criteria. This study examined the expected effects of omalizumab over 5 years on a representative sample of all patients eligible for omalizumab in the US.

METHODS

The Archimedes Asthma Model was used to simulate the following treatment scenarios for US patients age 12 and older with moderate-to-severe persistent allergic asthma: (1) Current asthma treatment (CAT) (treatment according to National Heart, Lung, and Blood Institute (NHLBI) guidelines, without use of omalizumab, and with adherence levels as observed in the National Asthma Survey); (2) Guideline asthma treatment (GAT) without omalizumab (NHLBI guidelines without use of omalizumab, assuming perfect adherence); (3) GAT plus omalizumab; and (4) GAT plus omalizumab with steroid reduction. The simulation was run for 5 years.

MAIN OUTCOME MEASURES

Symptom days, asthma exacerbations, emergency room/urgent care (ER/UC) visits, hospitalizations, and medication use.

RESULTS

For the full simulated population of omalizumab-eligible patients, the simulation forecasted that omalizumab would decrease cumulative exacerbations by 30%, ER/UC visits by 37%, and hospitalizations by 38% over 5 years. Among responders to omalizumab, assuming that 60.5% of patients respond, the results suggest that omalizumab would decrease cumulative exacerbations by 50%, ER/UC visits by 62%, and hospitalizations by 63% over 5 years. In addition, the simulation predicted that omalizumab would allow 45% of patients who are taking more than the minimum steroid dose to reduce their steroid dose, while maintaining similar asthma control as achieved in the GAT plus omalizumab arm (no steroid dose reduction) and better asthma control than following treatment protocols that do not include omalizumab.

CONCLUSION

Based on the results of this simulation, omalizumab is effective for those who respond, reducing serious events by more than 50% among the responder group, while also allowing many patients to reduce their steroid dose.

Health benefits and cost-effectiveness of primary genetic screening for Lynch syndrome in the general population

In current clinical practice, genetic testing to detect Lynch syndrome mutations ideally begins with diagnostic testing of an individual affected with cancer before offering predictive testing to at-risk relatives. An alternative strategy that warrants exploration involves screening unaffected individuals via demographic and family histories, and offering genetic testing to those individuals whose risks for carrying a mutation exceed a selected threshold. Whether this approach would improve health outcomes in a manner that is cost-effective relative to current standards of care has yet to be demonstrated. To do so, we developed a simulation framework that integrated models of colorectal and endometrial cancers with a 5-generation family history model to predict health and economic outcomes of 20 primary screening strategies (at a wide range of compliance levels) aimed at detecting individuals with mismatch repair gene mutations and their at-risk relatives. These strategies were characterized by (i) different screening ages for starting risk assessment and (ii) different risk thresholds above which to implement genetic testing. For each strategy, 100,000 simulated individuals, representative of the U.S. population, were followed from the age of 20, and the outcomes were compared with current practice. Findings indicated that risk assessment starting at ages 25, 30, or 35, followed by genetic testing of those with mutation risks exceeding 5%, reduced colorectal and endometrial cancer incidence in mutation carriers by approximately 12.4% and 8.8%, respectively. For a population of 100,000 individuals containing 392 mutation carriers, this strategy increased quality-adjusted life-years (QALY) by approximately 135 with an average cost-effectiveness ratio of $26,000 per QALY. The cost-effectiveness of screening for mismatch repair gene mutations is comparable to that of accepted cancer screening activities in the general population such as colorectal cancer screening, cervical cancer screening, and breast cancer screening. These results suggest that primary screening of individuals for mismatch repair gene mutations, starting with risk assessment between the ages of 25 and 35, followed by genetic testing of those whose risk exceeds 5%, is a strategy that could improve health outcomes in a cost-effective manner relative to current practice.

Identification of undiagnosed type 2 diabetes by systolic blood pressure and waist-to-hip ratio

AIMS/HYPOTHESIS

We estimated the current prevalence of type 2 diabetes in the Vietnamese population and developed simple diagnostic models for identifying individuals at high risk of undiagnosed type 2 diabetes.

METHODS

The study was designed as a cross-sectional investigation with 721 men and 1,421 women, who were aged between 30 and 72 years and were randomly sampled from Ho Chi Minh City (formerly Saigon) in Vietnam. A 75 g oral glucose tolerance test to assess fasting and 2 h plasma glucose concentrations were determined for each individual. The ADA diagnostic criteria were used to determine the prevalence of type 2 diabetes. WHR and blood pressure were also measured in all individuals.

RESULTS

The prevalence of type 2 diabetes was 10.8% in men and 11.7% in women. Higher WHR and blood pressure were independently associated with a greater risk of type 2 diabetes. Compared with participants without central obesity and hypertension, the odds of diabetes was increased by 6.4-fold (95% CI 3.2-13.0) in men and 4.1-fold (2.2-7.6) in women with central obesity and hypertension. Two nomograms were developed that help identify men and women at high risk of type 2 diabetes.

CONCLUSIONS/INTERPRETATION

The current prevalence of type 2 diabetes in the Vietnamese population is high. Simple field measurements such as waist-to-hip ratio and systolic blood pressure can identify individuals at high risk of undiagnosed type 2 diabetes.

Screening for type 2 diabetes: an update of the evidence

A growing body of evidence on diabetes screening has been published during the last 10 years. Type 2 diabetes meets many but not all of the criteria for screening. Concerns about potential harms of screening have largely been resolved. Screening identifies a high-risk population with the potential to gain from widely available interventions. However, in spite of the findings of modelling studies, the size of the benefit of earlier initiation of treatment and the overall cost-effectiveness remains uncertain, in contrast to other screening programmes (such as for abdominal aortic aneurysms) that are yet to be fully implemented. There is also uncertainty about optimal specifications and implementation of a screening programme, and further work to complete concerning development and delivery of individual- and population-level preventive strategies. While there is growing evidence of the net benefit of earlier detection of individuals with prevalent but undiagnosed diabetes, there remains limited justification for a policy of universal population-based screening for type 2 diabetes at the present time. Data from ongoing studies should inform the key assumptions in existing modelling studies and further reduce uncertainty.

A1C to detect diabetes in healthy adults: when should we recheck?

OBJECTIVE

To evaluate the optimal interval for rechecking A1C levels below the diagnostic threshold of 6.5% for healthy adults.

RESEARCH DESIGN AND METHODS

This was a retrospective cohort study. Participants were 16,313 apparently healthy Japanese adults not taking glucose-lowering medications at baseline. Annual A1C measures from 2005 to 2008 at the Center for Preventive Medicine, a community teaching hospital in Japan, estimated cumulative incidence of diabetes.

RESULTS

Mean age (+/-SD) of participants was 49.7 +/- 12.3 years, and 53% were male. Mean A1C at baseline was 5.4 +/- 0.5%. At 3 years, for those with A1C at baseline of <5.0%, 5.0-5.4%, 5.5-5.9%, and 6.0-6.4%, cumulative incidence (95% CI) was 0.05% (0.001-0.3), 0.05% (0.01-0.11), 1.2% (0.9-1.6), and 20% (18-23), respectively.

CONCLUSIONS

In those with an A1C <6.0%, rescreening at intervals shorter than 3 years identifies few individuals (approximately <or=1%) with an A1C >or=6.5%.

Cost-effectiveness of interventions to prevent and control diabetes mellitus: a systematic review

OBJECTIVE

To synthesize the cost-effectiveness (CE) of interventions to prevent and control diabetes, its complications, and comorbidities.

RESEARCH DESIGN AND METHODS

We conducted a systematic review of literature on the CE of diabetes interventions recommended by the American Diabetes Association (ADA) and published between January 1985 and May 2008. We categorized the strength of evidence about the CE of an intervention as strong, supportive, or uncertain. CEs were classified as cost saving (more health benefit at a lower cost), very cost-effective (<or=$25,000 per life year gained [LYG] or quality-adjusted life year [QALY]), cost-effective ($25,001 to $50,000 per LYG or QALY), marginally cost-effective ($50,001 to $100,000 per LYG or QALY), or not cost-effective (>$100,000 per LYG or QALY). The CE classification of an intervention was reported separately by country setting (U.S. or other developed countries) if CE varied by where the intervention was implemented. Costs were measured in 2007 U.S. dollars.

RESULTS

Fifty-six studies from 20 countries met the inclusion criteria. A large majority of the ADA recommended interventions are cost-effective. We found strong evidence to classify the following interventions as cost saving or very cost-effective: (I) Cost saving- 1) ACE inhibitor (ACEI) therapy for intensive hypertension control compared with standard hypertension control; 2) ACEI or angiotensin receptor blocker (ARB) therapy to prevent end-stage renal disease (ESRD) compared with no ACEI or ARB treatment; 3) early irbesartan therapy (at the microalbuminuria stage) to prevent ESRD compared with later treatment (at the macroalbuminuria stage); 4) comprehensive foot care to prevent ulcers compared with usual care; 5) multi-component interventions for diabetic risk factor control and early detection of complications compared with conventional insulin therapy for persons with type 1 diabetes; and 6) multi-component interventions for diabetic risk factor control and early detection of complications compared with standard glycemic control for persons with type 2 diabetes. (II) Very cost-effective- 1) intensive lifestyle interventions to prevent type 2 diabetes among persons with impaired glucose tolerance compared with standard lifestyle recommendations; 2) universal opportunistic screening for undiagnosed type 2 diabetes in African Americans between 45 and 54 years old; 3) intensive glycemic control as implemented in the UK Prospective Diabetes Study in persons with newly diagnosed type 2 diabetes compared with conventional glycemic control; 4) statin therapy for secondary prevention of cardiovascular disease compared with no statin therapy; 5) counseling and treatment for smoking cessation compared with no counseling and treatment; 6) annual screening for diabetic retinopathy and ensuing treatment in persons with type 1 diabetes compared with no screening; 7) annual screening for diabetic retinopathy and ensuing treatment in persons with type 2 diabetes compared with no screening; and 8) immediate vitrectomy to treat diabetic retinopathy compared with deferred vitrectomy.

CONCLUSIONS

Many interventions intended to prevent/control diabetes are cost saving or very cost-effective and supported by strong evidence. Policy makers should consider giving these interventions a higher priority.

Cardiovascular disease risk factors, type 2 diabetes mellitus, and the Framingham Heart Study

Type 2 diabetes is a common disorder and an important risk factor for cardiovascular disease. The Framingham Heart Study is a population-based epidemiologic study that has contributed to our knowledge of cardiovascular disease and its risk factors. This review will focus on the contemporary contributions of the Framingham Heart Study to the field of diabetes epidemiology, including data on diabetes trends, genetics, and future advances in population-based studies.