Screening for type 2 diabetes in a multiethnic setting using known risk factors to identify those at high risk: a cross-sectional study

Risk of Developing Type 2 Diabetes Mellitus in South Asian Women with History of Gestational Diabetes Mellitus: A Systematic Review and Meta-Analysis

BACKGROUND

Gestational diabetes mellitus (GDM) and type 2 diabetes mellitus (T2DM) represent two different components of the spectrum of diabetes mellitus (DM). Women with GDM have a high chance of developing T2DM in later life and this relative risk depends on a number of factors including ethnicity.

AIM

To compare and estimate the risk of developing T2DM in South Asian women with a history of GDM compared to those without a history of GDM.

METHODS

This is a systematic review of PubMed and MEDLINE articles reporting the progression of GDM to T2DM that were published in English from 2000 to 2020. We performed meta-analysis to calculate risk ratios (RR).

RESULTS

We selected 6 studies considering the inclusion and exclusion criteria after sorting 25 full-text articles. Of the 44165 South Asian women assessed, 3095 had GDM and 41070 were without GDM. 995 women in GDM group and 1525 women in non-GDM group had developed T2DM. The RR of women with GDM over non-GDM in developing T2DM was 10.81 (95% confidence interval (CI): 7.61-15.35) suggesting that women with GDM are at 10.81 times more risk of developing T2DM than non-GDM. The cumulative incidence of T2DM in GDM group was 17.34% at 5 years of follow-up and 33% at more than 10 years of follow-up.

CONCLUSION

The risk of developing T2DM in later life is higher in South Asian women with GDM than without GDM. Therefore, lifestyle and pharmacological interventions, patient communication, timely screening, and long-term follow-up of GDM patients are important to reduce the risk.

A community-based primary prevention programme for type 2 diabetes mellitus integrating identification and lifestyle intervention for prevention: a cluster randomised controlled trial

Background

Prevention of type 2 diabetes mellitus (T2DM) is a global priority; however, there is a lack of evidence investigating how to effectively translate prevention research into a primary care setting.

Objectives

(1) To develop and validate a risk score to identify individuals at high risk of T2DM in the UK; and (2) to establish whether or not a structured education programme targeting lifestyle and behaviour change was clinically effective and cost-effective at preventing progression to T2DM in people with prediabetes mellitus (PDM), identified through a risk score screening programme in primary care.

Design

A targeted screening study followed by a cluster randomised controlled trial (RCT), with randomisation at practice level. Participants were followed up for 3 years.

Setting

A total of 44 general practices across Leicestershire, UK. The intervention took place in the community.

Participants

A total of 17,972 individuals from 44 practices identified through the risk score as being at high risk of T2DM were invited for screening; of these, 3449 (19.2%) individuals attended. All received an oral glucose tolerance test. PDM was detected in 880 (25.5%) of those screened. Those with PDM were included in the trial; of these, 36% were female, the average age was 64 years and 16% were from an ethnic minority group.

Intervention

Practices were randomised to receive either standard care or the intervention. The intervention consisted of a 6-hour group structured education programme, with an annual refresher and regular telephone contact.

Main outcome measures

The primary outcome was progression to T2DM. The main secondary outcomes were changes in glycated haemoglobin concentrations, blood glucose levels, cardiovascular risk, the presence of metabolic syndrome, step count and the cost-effectiveness of the intervention.

Results

A total of 22.6% of the intervention group did not attend the education and 29.1% attended all sessions. A total of 131 participants developed T2DM (standard care,n = 67; intervention,n = 64). There was a 26% reduced risk of T2DM in the intervention arm compared with standard care, but this did not reach statistical significance (hazard ratio 0.74, 95% confidence interval 0.48 to 1.14;p = 0.18). There were statistically significant improvements in glycated haemoglobin concentrations, low-density lipoprotein cholesterol levels, psychosocial well-being, sedentary time and step count in the intervention group. The intervention was found to result in a net gain of 0.046 quality-adjusted life-years over 3 years at a cost of £168 per patient, with an incremental cost-effectiveness ratio of £3643 and a probability of 0.86 of being cost-effective at a willingness-to-pay threshold of £20,000.

Conclusions

We developed and validated a risk score for detecting those at high risk of undiagnosed PDM/T2DM. We screened > 3400 people using a two-stage screening programme. The RCT showed that a relatively low-resource pragmatic programme may lead to a reduction in T2DM and improved biomedical and psychosocial outcomes, and is cost-effective.

Limitations

Only 19% of those invited to screening attended, which may limit generalisability. The variation in cluster size in the RCT may have limited the power of the study.

Future work

Future work should focus on increasing attendance to both screening and prevention programmes and offering the programme in different modalities, such as web-based modalities. A longer-term follow-up of the RCT participants would be valuable.

Trial registration

Current Controlled Trials ISRCTN80605705.

Funding

The National Institute for Health Research Programme Grants for Applied Research programme.

The cost-effectiveness of testing strategies for type 2 diabetes: a modelling study

BACKGROUND

An estimated 850,000 people have diabetes without knowing it and as many as 7 million more are at high risk of developing it. Within the NHS Health Checks programme, blood glucose testing can be undertaken using a fasting plasma glucose (FPG) or a glycated haemoglobin (HbA1c) test but the relative cost-effectiveness of these is unknown.

OBJECTIVES

To estimate and compare the cost-effectiveness of screening for type 2 diabetes using a HbA1c test versus a FPG test. In addition, to compare the use of a random capillary glucose (RCG) test versus a non-invasive risk score to prioritise individuals who should undertake a HbA1c or FPG test.

DESIGN

Cost-effectiveness analysis using the Sheffield Type 2 Diabetes Model to model lifetime incidence of complications, costs and health benefits of screening.

SETTING

England; population in the 40-74-years age range eligible for a NHS health check.

DATA SOURCES

The Leicester Ethnic Atherosclerosis and Diabetes Risk (LEADER) data set was used to analyse prevalence and screening outcomes for a multiethnic population. Alternative prevalence rates were obtained from the literature or through personal communication.

METHODS

(1) Modelling of screening pathways to determine the cost per case detected followed by long-term modelling of glucose progression and complications associated with hyperglycaemia; and (2) calculation of the costs and health-related quality of life arising from complications and calculation of overall cost per quality-adjusted life-year (QALY), net monetary benefit and the likelihood of cost-effectiveness.

RESULTS

Based on the LEADER data set from a multiethnic population, the results indicate that screening using a HbA1c test is more cost-effective than using a FPG. For National Institute for Health and Care Excellence (NICE)-recommended screening strategies, HbA1c leads to a cost saving of £12 and a QALY gain of 0.0220 per person when a risk score is used as a prescreen. With no prescreen, the cost saving is £30 with a QALY gain of 0.0224. Probabilistic sensitivity analysis indicates that the likelihood of HbA1c being more cost-effective than FPG is 98% and 95% with and without a risk score, respectively. One-way sensitivity analyses indicate that the results based on prevalence in the LEADER data set are insensitive to a variety of alternative assumptions. However, where a region of the country has a very different joint HbA1c and FPG distribution from the LEADER data set such that a FPG test yields a much higher prevalence of high-risk cases relative to HbA1c, FPG may be more cost-effective. The degree to which the FPG-based prevalence would have to be higher depends very much on the uncertain relative uptake rates of the two tests. Using a risk score such as the Leicester Practice Database Score (LPDS) appears to be more cost-effective than using a RCG test to identify individuals with the highest risk of diabetes who should undergo blood testing.

LIMITATIONS

We did not include rescreening because there was an absence of required relevant evidence.

CONCLUSIONS

Based on the multiethnic LEADER population, among individuals currently attending NHS Health Checks, it is more cost-effective to screen for diabetes using a HbA1c test than using a FPG test. However, in some localities, the prevalence of diabetes and high risk of diabetes may be higher for FPG relative to HbA1c than in the LEADER cohort. In such cases, whether or not it still holds that HbA1c is likely to be more cost-effective than FPG depends on the relative uptake rates for HbA1c and FPG. Use of the LPDS appears to be more cost-effective than a RCG test for prescreening.

FUNDING

The National Institute for Health Research Health Technology Assessment programme.

Diabetic kidney disease: world wide difference of prevalence and risk factors

Diabetic kidney disease - which is defined by elevated urine albumin excretion or reduced glomerular filtration rate (GFR) or both - is a serious complication that occurs in 20% to 40% of all diabetics. In this review we try to highlight the prevalence of diabetic nephropathy which is not uncommon complication of diabetes all over the world. The prevalence of diabetes worldwide has extended epidemic magnitudes and is expected to affect more than 350 million people by the year 2035. There is marked racial/ethnic besides international difference in the epidemiology of diabetic kidney disease which could be explained by the differences in economic viability and governmental infrastructures. Approximately one-third of diabetic patients showed microalbuminuria after 15 years of disease duration and less than half develop real nephropathy. Diabetic kidney disease (DKD) is more frequent in African-Americans, Asian-Americans, and Native Americans. Progressive kidney disease is more frequent in Caucasians patients with type 1 than type 2 diabetes mellitus (DM), although its overall prevalence in the diabetic population is higher in patients with type 2 DM while this type of DM is more prevalent. Hyperglycemia is well known risk factor for in addition to other risk factors like male sex, obesity, hypertension, chronic inflammation, resistance to insulin, hypovitaminosis D, and dyslipidemia and some genetic loci and polymorphisms in specific genes. Management of its modifiable risk factors might help in reducing its incidence in the nearby future.

Adipocytokine associations with insulin resistance in british South asians

Aims. Adipocytokines are implicated in the pathogenesis of type 2 diabetes and may represent identifiable precursors of metabolic disease within high-risk groups. We investigated adiponectin, leptin, and TNF- α and assessed the contribution of these molecules to insulin resistance in south Asians. Hypothesis. South Asians have adverse adipocytokine profiles which associate with an HOMA-derived insulin resistance phenotype. Methods. We measured adipocytokine concentrations in south Asians with newly diagnosed impaired glucose tolerance or Type 2 Diabetes Mellitus in a case-control study. 158 (48.5% males) volunteers aged 25-75 years with risk factors for diabetes but no known vascular or metabolic disease provided serum samples for ELISA and bioplex assays. Results. Total adiponectin concentration progressively decreased across the glucose spectrum in both sexes. A reciprocal trend in leptin concentration was observed only in south Asian men. Adiponectin but not leptin independently associated with HOMA-derived insulin resistance after logistic multivariate regression. Conclusion. Diasporic south Asian populations have an adverse adipocytokine profile which deteriorates further with glucose dysregulation. Insulin resistance is inversely associated with adiponectin independent of BMI and waist circumference in south Asians, implying that adipocytokine interplay contributes to the pathogenesis of metabolic disease in this group.

Primary prevention of Type 2 diabetes in South Asians--challenges and the way forward

Preventing diabetes is of enormous value, particularly for the South Asian countries, which have a huge healthcare burden from the onslaught of the disease. Type 2 diabetes has been proved to be preventable using lifestyle changes, even in South Asians despite their heightened risk profile. Strategies to improve awareness about diabetes and translation of preventive measures by innovative, culturally specific programmes have to be implemented at national levels. Integrated involvement of the government, community, media, healthcare and education services, and financial support from national and international organizations, are required. South Asian countries have initiated national programmes for diabetes prevention and management. It is also encouraging to note that joint ventures between developed countries such as the USA, UK and other European countries and centres of excellence in South Asia have been initiated to develop large-scale, community-oriented, pragmatic intervention strategies.

Diagnostic performance of using one- or two-HbA1c cut-point strategies to detect undiagnosed type 2 diabetes and impaired glucose regulation within a multi-ethnic population

INTRODUCTION

We compared test performance and cost per case for strategies detecting diabetes on the oral glucose tolerance test (OGTT) using either (a) glycated haemoglobin (HbA1c) ≥ 6.5% (48 mmol/mol) or (b) two HbA1c thresholds where the first cut-point 'rules out' and the second 'rules in' diabetes. HbA1c values in between the thresholds require confirmatory glucose testing for diagnosis.

MATERIALS AND METHODS

We conducted an analysis of adults aged 40-75 years from the Leicester Ethnic Atherosclerosis and Diabetes Risk (LEADER) cohort (Leicester, UK), from 2002 to 2008, who underwent oral glucose tolerance testing (OGTT) and HbA1c testing.

RESULTS

From 8696 individuals (mean age 57.3 years, 73% white Europeans (WE) and 27% South Asians (SA)), HbA1c ≥ 6.5% produced sensitivity of 62.1% for detecting diabetes in WE and 78.9% in SA. Using two selected thresholds, HbA1c ≤ 5.8% (rule-in, 40 mmol/mol) and HbA1c ≥ 6.8% (rule-out, 51 mmol/mol) produced high sensitivity/specificity (> 91.0%) for detecting diabetes, however, 28.8% of the cohort with HbA1c 5.9%-6.7% required a subsequent glucose test. The two cut-point threshold produced a lower cost per case of diabetes detected in WE, compared to HbA1c ≥ 6.5% of £38.53 (1.89 to 86.81) per case, but was more expensive in SA by £84.50 (69.72 to 100.92) per case. Using a risk score to determine HbA1c testing, the same costs per case became £63.33 (23.33 to 113.26) in WE and £69.21 (55.60 to 82.41) in SA.

CONCLUSION

Using a two-threshold strategy may have some benefits over a single cut-point; however, 28.8% of individuals required two blood tests.

Implementation of the automated Leicester Practice Risk Score in two diabetes prevention trials provides a high yield of people with abnormal glucose tolerance

AIMS/HYPOTHESIS

The Leicester Practice Risk Score (LPRS) is a tool for identifying those at high risk of either impaired glucose regulation (IGR), defined as impaired glucose tolerance and/or impaired fasting glucose, or type 2 diabetes from routine primary care data. The aim of this study was to determine the yield from the LPRS when applied in two diabetes prevention trials.

METHODS

Let's Prevent Diabetes (LPD) and Walking Away from Diabetes (WAD) studies used the LPRS to identify people at risk of IGR or type 2 diabetes from 54 general practices. The top 10% at risk within each practice were invited for screening using a 75 g OGTT. The response rate to the invitation and the prevalence of IGR and/or type 2 diabetes in each study were calculated.

RESULTS

Of those invited 19.2% (n = 3,449) in LPD and 22.1% (n = 833) in WAD attended. Of those screened for LPD 25.5% (95% CI 24.1, 27.0) had IGR and 4.5% (95% CI 3.8, 5.2) had type 2 diabetes, giving a prevalence of any abnormal glucose tolerance of 30.1% (95% CI 28.5, 31.6). Comparable rates were seen for the WAD study: IGR 26.5% (95% CI 23.5, 29.5), type 2 diabetes 3.0% (95% CI 1.8, 4.2) and IGR/type 2 diabetes 29.5% (95% CI 26.4, 32.6).

CONCLUSIONS/INTERPRETATION

Using the LPRS identifies a high yield of people with abnormal glucose tolerance, significantly higher than those seen in a population screening programme in the same locality. The LPRS is an inexpensive and simple way of targeting screening programmes at those with the highest risk.

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.

Screening for diabetes using an oral glucose tolerance test within a western multi-ethnic population identifies modifiable cardiovascular risk: the ADDITION-Leicester study

AIMS/HYPOTHESIS

The aim of this study was to determine the frequency of undiagnosed glucose abnormalities and the burden of cardiovascular disease (CVD) risk among south Asians and white Europeans attending a systematic screening programme for type 2 diabetes (ADDITION-Leicester) and to estimate the achievable risk reduction in individuals identified with glucose disorders.

METHODS

Random samples of individuals (n = 66,320) from 20 general practices were invited for a 75 g OGTT and CVD risk assessment. Ten-year CVD risk among screen-detected people with diabetes or impaired glucose regulation (IGR) (impaired fasting glycaemia and/or impaired glucose tolerance [IGT]) was computed using the Framingham-based ETHRISK engine and achievable risk reduction was predicted using relative reductions for treatments extracted from published trials.

RESULTS

A total of 6,041 participants (48% male, 22% south Asian) aged 40-75 years inclusive were included. Undiagnosed glucose disorders occurred more frequently in south Asians than white Europeans; age and sex adjusted odds ratios were 1.74 (95% CI 1.42-2.13) and 2.30 (95% CI 1.68-3.16) for IGT and diabetes respectively. Prevalence of any undetected glucose disorder was 17.5% in the whole cohort. Adjusted 10-year risk was similar in screen-detected people with IGR and diabetes (18.3% vs 21.6%), and was higher in south Asians across the glucose spectrum. Absolute CVD risk reductions of up to 13% in those with screen-detected type 2 diabetes and 6% in IGR are achievable using existing cardioprotective therapies.

CONCLUSIONS/INTERPRETATION

Population screening with an OGTT identifies a significant burden of modifiable CVD risk, especially within south Asian groups. Strategies enticing this population to consider screening programmes are urgently needed as significant risk reduction is possible once a glucose abnormality is identified.

TRIAL REGISTRATION

ClinicalTrials.gov NCT00318032.

FUNDING

The project is funded for support and treatment costs by NHS Department of Health Support for Science and project grants.

Contrasting cardiovascular risk profiles and prescribed cardio-protective therapies in newly-diagnosed type 2 diabetes identified through screening and standard practice

AIMS

Screening for Type 2 diabetes mellitus (T2DM) may improve long-term outcomes by managing cardiovascular risk at an earlier stage of the disease. The cardiovascular risk profile of screen-detected (SD) T2DM is ill defined and has not been compared to conventional newly diagnosed (CD) cases.

METHODS

Baseline data from SD (n=337) and CD (n=824) cohorts were compared. SD adopted mixed approaches to screening, population based (n=214) and cardiovascular-risk factor targeted (n=123). CD reflected UK primary care practice with cases referred within four weeks of diagnosis.

RESULTS

People with SD T2DM were leaner, had a lower HbA1c(%) and lower triglyceride but were more hypertensive compared to people with CD T2DM. Fewer SD were on blood pressure lowering (46% vs. 60%, p<0.0001), statin (30% vs. 41%, p<0.0001) or anti-platelet (15% vs. 27%, p<0.0001) therapies. Modelled 10 year cardiovascular disease (CVD) risk was actually greater in the SD group compared to CD (CVD: 20.8 vs. 17.2, p=0.0001).

CONCLUSION

Individuals with SD T2DM are at high risk of CVD as a result of untreated hyperglycaemia, hypertension and dyslipidaemia. Those prescribed antihypertensive or lipid-lowering therapies frequently still had inadequate control. Identifying vascular risk by screening for latent glucose disease provides therapeutic opportunities for earlier intervention.