Prevalence of prediabetes and associated risk factors in a rural Nigerian community

There is very scanty population-based data on the prevalence of prediabetes, a forerunner to type 2 diabetes, in both rural and urban Nigeria. The purpose of the study was to determine the prevalence and risk factors for prediabetes in a rural Nigerian population. A cross-sectional, village by village, clan-based stratified convenient sampling was done in Ihuokpara, a rural community in Nkanu East Local Government Area of Enugu State, Nigeria. A total of 824 adult men and women participated. Questionnaires were used to obtain sociodemographic data, awareness of diabetes, and common symptoms including family history of diabetes. Fasting plasma glucose and 2-hour post 75g-glucose-load plasma glucose levels were measured after the subjects’ blood pressure and anthropometric indices were obtained. Fasting lipid profile was also assessed in a subset of the study population. Males constituted 34.7 % of the 824 participants. The mean age of the subjects was 51.1?±?16.2 years. Prevalence of impaired fasting glucose (IFG) was 9.2 %, while that of impaired glucose tolerance (IGT) was 15.8 %. The overall prevalence of prediabetes (both IGT and IFG) was 21.5 %. Hypertension was prevalent at 45.3 % and was the strongest predictor of prediabetes. Obesity was prevalent at 5.8 % and overweight at 16.7 %, while 15.7 % had central obesity. Prevalence of prediabetes was high in the community with hypertension emerging as the possible driving force.     

Dental Clinics as Potent Sources for Screening Undiagnosed Diabetes and Prediabetes

IntroductionThis pilot study investigated the efficacy of dental clinics as potent sources for screening diabetes and prediabetes in undiagnosed individuals.MethodsData were randomly collected from 385 patients (aged 40 years and older) visiting dental clinics. Patients already having a diagnosis of diabetes and/or prediabetes were excluded. Demographic data, body mass index and family and dental histories were recorded. Signs and symptoms of diabetes were investigated. Random blood glucose levels (RBGLs) were recorded. Individuals with RBGL ≥110 mg/dL underwent the oral glucose tolerance test and the glycosylated hemoglobin test (HbA1c).ResultsOf the 385 patients, 60% (232) had RBGL <110 mg/dL, whereas 40% (153) had RBGL ≥110 mg/dL. Prevalence of confirmed diabetes and prediabetes among the study participants was 16.4% and 15.8%, respectively. Body mass index was significantly higher among patients with diabetes and prediabetes as compared with healthy controls. HbA1c level was statistically significantly higher among patients with diabetes than among patients with prediabetes. Symptoms of polyuria and polydipsia were significantly higher among patients with diabetes than in those without diabetes.ConclusionsA high percentage of undiagnosed type 2 diabetes and prediabetes among patients visiting dental clinics was found compared with that reported in the medical literature. Further studies with a lager sample size are needed to confirm these results.     

Elevated depressive symptoms and risk of all-cause and cardiovascular mortality among adults with and without diabetes: The REasons for Geographic And Racial Differences in Stroke (REGARDS) study

AimsTo examine the association of elevated depressive symptoms with all-cause and cardiovascular disease (CVD) mortality and determine whether these associations differ for those with and without diabetes.MethodsWe included 22,807 black and white men and women aged 45–98 years at baseline (2003–2007) from the REasons for Geographic And Racial Differences in Stroke (REGARDS) Study. Elevated depressive symptoms were defined as a score ≥ 4 on the 4-item Centers for Epidemiologic Studies of Depression Scale. Participants were classified as having diabetes, prediabetes, or no prediabetes/diabetes based on glucose levels and diabetes medication use. All-cause mortality events were available through 2018 and adjudicated CVD mortality events were available through 2015.ResultsDuring follow-up, there were 5383 all-cause deaths, of which 1585 were adjudicated CVD deaths. The mean survival time was lower for participants with elevated depressive symptoms than those without elevated depressive symptoms for those with diabetes, prediabetes, and no prediabetes/diabetes. In multivariable adjusted models, elevated depressive symptoms increased the risk of all-cause mortality for those with diabetes (HR = 1.15; 95% CI = 1.00–1.32), prediabetes (HR = 1.56; 95% CI = 1.28–1.91), and neither prediabetes/diabetes (HR = 1.34; 95% CI = 1.19–1.50) (p for interaction = 0.0342). Findings were similar for CVD mortality.ConclusionElevated depressive symptoms increased the risk of all-cause and CVD mortality among individuals with and without diabetes, with a stronger magnitude of association observed among those with prediabetes. This underscores the need for assessing depressive symptoms across the glycemic spectrum, including those with prediabetes.     

Early vascular lesions in subjects with metabolic syndrome and prediabetes.

AIM: The metabolic syndrome (MetS) is a cluster of cardiovascular risk factors, while prediabetes, identified by impaired fasting glucose (IFG) and/or impaired glucose tolerance (IGT), predicts future development of diabetes mellitus. Although MetS and prediabetes have a strong interrelation, it is unclear whether they denote the same risk for cardiovascular complications. The aim of the study was to compare overweight and obese individuals with MetS and prediabetes in terms of early carotid artery atheromatosis and renal dysfunction. METHODS: A total of 524 overweight and obese (body mass index, BMI = or >27 kg/m2) adults, mean age 56.7+/-11.8 years, 264 men and 260 women, were studied. All participants underwent a thorough clinical and laboratory evaluation, including an oral glucose tolerance test. Carotid artery ultrasonography was performed and 24 h urine albumin excretion was measured. NCEP-ATP III and ADA criteria were used for the diagnosis of MetS and prediabetes. RESULTS: Overall, 129 individuals (24.6%) had MetS without prediabetes and another 59 (11.3%) prediabetes without MetS. Individuals with prediabetes had lower albumin excretion (P=0.033) and more thickened common carotid intima-media in comparison to those with MetS (P=0.032). Furthermore, MetS was associated with higher C-reactive protein levels in comparison to prediabetes (P=0.05). CONCLUSIONS: The MetS seems to have a more pronounced impact on early renal dysfunction than prediabetes, while the latter to early carotid artery structural changes.     

What is the best treatment for prediabetes?

Worldwide, along with the increasing prevalence of obesity, the number of people with prediabetes is increasing. The diagnostic criteria for prediabetes include impaired fasting glucose, impaired glucose tolerance, and metabolic syndrome. The presence of two or more of these three criteria renders a person at high risk for future diabetes. The treatment goal of prediabetes is to prevent future development of type 2 diabetes and diabetes-related cardiovascular complications. The treatment approach is twofold: glycemic control and control of cardiovascular risk factors, mainly hypertension and hyperlipidemia. Intensive lifestyle modification is the mainstay of treatment in low-risk patients. When lifestyle modification fails and in high-risk patients, medications such as metformin and/or acarbose are recommended. For high-risk patients and those who progress despite intensive lifestyle modification, thiazolidinediones are also recommended. The goals for cardiovascular risk factor control are similar to those for patients with diabetes.     

Role of various indices derived from an oral glucose tolerance test in the prediction of conversion from prediabetes to type 2 diabetes

AimsThe clinical implications of prediabetes for development of type 2 diabetes may differ for Asian ethnicity. We investigated various indices derived from a 2-h oral glucose tolerance test (OGTT) in people with prediabetes to predict their future risk of diabetes.MethodsWe recruited 406 consecutive subjects with prediabetes from 2005 to 2006 and followed them up every 3–6 months for up to 9 years. Prediabetes was defined as isolated impaired fasting glucose (IFG), isolated impaired glucose tolerance (IGT), combined glucose intolerance (CGI), or isolated elevated HbA1c (5.7–6.4%, 39–46 mmol/mol) without IFG or IGT. The rate of diabetes conversion was compared between prediabetes categories. The association of glycemic indices with development of diabetes was also investigated.ResultsEighty-one patients were diagnosed with diabetes during the 9-year follow-up (median 46.0 months). The rate of diabetes conversion was higher in subjects with CGI (31.9%), or isolated IGT (18.5%) than in those with isolated IFG (15.2%) or isolated elevated HbA1c (10.9%). Surrogate markers reflecting β-cell dysfunction were more closely associated with diabetes conversion than insulin resistance indices. Subjects with a 30-min postload glucose ≥165 mg/dL and a 30-min C-peptide <5 ng/mL had 8.83 times greater risk (95% confidence interval 2.98–26.16) of developing diabetes than other prediabetic subjects.ConclusionsIn Asians, at least Koreans, β-cell dysfunction seems to be the major determinant for diabetes conversion. A combination of high glucose and low C-peptide levels at 30 min after OGTT may be a good predictor for diabetes conversion in this population.     

Greater adverse effects of cholesterol and diabetes on carotid intima-media thickness in South Asian Indians: comparison of risk factor-IMT associations in two population-based surveys

Asian Indians appear particularly susceptible to coronary heart disease compared with other ethnic groups. We compared the effects of vascular risk factors on carotid intima–media thickness (IMT) in a population of South Asians from Andhra Pradesh, India with a population of Caucasians from Perth, Australia.Cardiovascular risk factors and ultrasound-assessed carotid IMT were measured in randomly selected adults from two villages in rural India (n = 303) and compared to those for randomly sampled adults from Australia (n = 1111). Regression models with interaction terms were used to compare the strengths of associations between risk factors and carotid IMT, in these two populations. There were stronger associations of cholesterol (p for interaction = 0.009) and diabetes (p = 0.04) with carotid IMT in the Indian compared to the Australian population. Also, while increasing HDL-cholesterol was associated with decreasing carotid IMT in the Australian population the reverse was true for the Indian population (p < 0.001). The associations with IMT of blood pressure, triglycerides, age, HDL to total cholesterol ratio, glucose, BMI, waist, waist to hip ratio and smoking were not different between the populations.Greater adverse effects of total cholesterol and diabetes on atherosclerosis and no protective effect of HDL-cholesterol amongst Asian Indians provide a novel possible explanation for observed excess rates of cardiovascular disease amongst these populations.     

Prevalence of Diabetes in Asian Indians Based on Glycated Hemoglobin and Fasting and 2-H Post-Load (75-g) Plasma Glucose (CURES-120)

Abstract Objective: With the introduction of glycated hemoglobin (A1c) as a method of screening for diabetes, it is essential to study how use of A1c would affect the prevalence of diabetes in different ethnic groups. We compared the prevalence of diabetes by fasting (FPG) and 2-h post-load (75-g) plasma glucose (2-h PG) and A1c criteria in an Asian Indian population. Research Design and Methods: Subjects (n=2,188) without known diabetes were drawn from the Chennai Urban Rural Epidemiological Study, a population-based study in Chennai, South India. FPG, 2-h PG, and A1c estimations were carried out. Prevalence rates of diabetes were compared using as cut points FPG ≥7?mmol/L (126?mg/dL), 2-hr PG ≥11.1?mmol/L (200?mg/dL), or A1c ≥6.5% criteria. Results: Prevalence of diabetes was 6.1% (n=134) using the FPG criterion, 10.1% (n=221) by the 2-h PG criterion, and 12.8% (n=281) by the A1c criterion. Thus the prevalence of diabetes by the A1c criterion was 110% and 27% higher than the FPG and 2-hr PG criteria, respectively. Only 121 of these subjects were identified by all three criteria. Subjects diagnosed by the A1c criteria had the lowest FPG, 2-h PG, A1c, and serum triglyceride levels. Conclusions: In Asian Indians, use of A1c criteria would result in markedly higher prevalence rates of diabetes. It also identifies a different set of individuals with milder glucose intolerance and lower serum triglyceride levels.     

Atherosclerotic Cardiovascular Disease or Heart Failure: First Cardiovascular Event in Adults With Prediabetes and Diabetes

BackgroundIndividuals with prediabetes and diabetes are at increased risk of atherosclerotic cardiovascular disease (ASCVD) and heart failure (HF). Whether ASCVD or HF is more likely to occur first in these populations within different race-sex groups is unknown.ObjectiveTo determine the competing risk for the first cardiovascular event by subtype in Black and white men and women with prediabetes and diabetes.MethodsIndividual-level data from adults without ASCVD or HF were pooled from 6 population-based cohorts. We estimated the competing cumulative incidences of ASCVD, HF and noncardiovascular death as the first event in middle-aged (40–59 years) and older (60–79 years) adults, stratified by race and sex, with normal fasting plasma glucose (FPG < 100 mg/dL), prediabetes (FPG 100–125 mg/dL) and diabetes (FPG ≥ 126 mg/dL or on antihyperglycemic agents) at baseline. Within each race-sex group, we estimated risk the adjusted hazard ratio of ASCVD, HF and noncardiovascular death in adults with prediabetes and diabetes relative to adults with normoglycemia after adjusting for cardiovascular risk factors.ResultsIn 40,117 participants with 638,910 person-years of follow-up, 5781 cases of incident ASCVD and 3179 cases of incident HF occurred. In middle-aged adults with diabetes, competing cumulative incidence of ASCVD as a first event was higher than HF in white men (35.4% vs 11.6%), Black men (31.6% vs 15.1%) and white women (24.3% vs 17.2%) but not in Black women (26.4% vs 28.4%). Within each group, the adjusted hazard ratio of ASCVD and HF was significantly higher in adults with diabetes than in adults with normal FPG levels. Findings were largely similar in middle-aged adults with prediabetes and older adults with prediabetes or diabetes.ConclusionsBlack women with diabetes are more likely to develop HF as their first CVD event, whereas individuals with diabetes from other race-sex groups are more likely to present first with ASCVD. These results can inform the tailoring of primary prevention therapies for either HF- or ASCVD-specific pathways based on individual-level risk.     

Relationship between urine pH and abnormal glucose tolerance in a community‐based study

Aims/Introduction

The association between urine pH and abnormal glucose tolerance in men and women is unclear; therefore, we carried out a community‐based, cross‐sectional study to investigate sex‐specific associations between these values, possible indicators of prediabetes and type 2 diabetes.

Materials and Methods

We enrolled 4,945 Japanese individuals (2,490 men and 2,455 women), who had undergone annual health checkups. To investigate the relationship between low urine pH and abnormal glucose tolerance, participants were divided into three groups based on their fasting plasma glucose levels (<6.11 mmol/L, 6.11–6.99 mmol/L and ≥6.99 mmol/L), and three groups based on their glycated hemoglobin levels (≤44.3 mmol/mol, 44.3–47.5 mmol/mol and ≥47.5 mmol/mol). To examine the effects of urine pH on abnormal glucose tolerance, participants were categorized into five groups based on their urine pH (5.0, 5.5, 6.0, 6.5 and ≥7.0).

Results

Multivariate analysis adjusted for age, body mass index, systolic blood pressure, triglycerides, high‐density lipoprotein cholesterol, uric acid, creatinine and antidiabetic agent use showed significant associations between low urine pH and both high fasting plasma glucose and high glycated hemoglobin levels (P for trend = 0.0260, 0.0075) in men. Furthermore, after the same adjustments, prevalence rates of abnormal glucose tolerance (≥6.11 mmol/L and ≥6.99 mmol/L), increased significantly as urine pH levels decreased (P for trend = 0.0483, 0.0181) in men. In women, a similar trend was observed without a significant difference.

Conclusions

Low urine pH is significantly associated with abnormal glucose tolerance; therefore, measuring urine pH might prove useful for identifying patients at high risk for diabetes.     

老年高血压糖尿病前期患者心血管危险因素分析

目的调查老年高血压合并糖尿病前期患者心血管危险因素分布。方法收集年龄≥60岁、既往无糖尿病病史、且入院空腹血糖(FPG)<7.0mmol/L的高血压患者388例,以空腹血糖受损(IFG)诊断标准为FPG≥5.6mmol/L,分为A组260例(FPG<5.6mmol/L)、B组65例(5.6mmol/L≤FPG<6.1mmol/L)及C组63例(6.1mmol/L≤FPG<7mmol/L),比较3组各种心血管危险因素分布的差异。结果 338例患者中,IFG患病率33.0%。与A组比较,B组和C组高血压≥2级或高血压高危、左心室舒张功能障碍、颈动脉增厚比例等无明显变化(P>0.05)。结论尽管未发现IFG与其他心血管危险因素有关,但糖代谢异常在此类患者中的影响应予重视。     

A randomized trial of improved weight loss with a prepared meal plan in overweight and obese patients: impact on cardiovascular risk reduction

OBJECTIVE: To assess the long-term effects of a prepackaged, nutritionally complete, prepared meal plan compared with a usual-care diet (UCD) on weight loss and cardiovascular risk factors in overweight and obese persons. DESIGN: In this randomized multicenter study, 302 persons with hypertension and dyslipidemia (n = 183) or with type 2 diabetes mellitus (n = 119) were randomized to the nutrient-fortified prepared meal plan (approximately 22% energy from fat, 58% from carbohydrate, and 20% from protein) or to a macronutrient-equivalent UCD. MAIN OUTCOME MEASURES: The primary outcome measure was weight change. Secondary measures were changes in blood pressure or plasma lipid, lipoprotein, glucose, or glycosylated hemoglobin levels; quality of life; nutrient intake; and dietary compliance. RESULTS: After 1 year, weight change in the hypertension/dyslipidemia group was -5.8+/-6.8 kg with the prepared meal plan vs -1.7+/-6.5 kg with the UCD plan (P<.001); for the type 2 diabetes mellitus group, the change was -3.0+/-5.4 kg with the prepared meal plan vs -1.0+/-3.8 kg with the UCD plan (P<.001) (data given as mean +/- SD). In both groups, both interventions improved blood pressure, total and low-density lipoprotein cholesterol levels, glycosylated hemoglobin level, and quality of life (P<.02); in the diabetic group, the glucose level was reduced (P<.001). Compared with those in the UCD group, participants with hypertension/dyslipidemia in the prepared meal plan group showed greater improvements in total (P<.01) and high-density lipoprotein (P<.03) cholesterol levels, systolic blood pressure (P<.03), and glucose level (P<.03); in participants with type 2 diabetes mellitus, there were greater improvements in glucose (P =.046) and glycosylated hemoglobin (P<.02) levels. The prepared meal plan group also showed greater improvements in quality of life (P<.05) and compliance (P<.001) than the UCD group. CONCLUSIONS: Long-term dietary interventions induced significant weight loss and improved cardiovascular risk in high-risk patients. The prepared meal plan simultaneously provided the simplicity and nutrient composition necessary to maintain long-term compliance and to reduce cardiovascular risk.     

The study of diabetes prevalence and related risk factors in Fuyang,a Chinese county under rapid urbanization

The fast urbanization of China potentially affects development of diabetes. Fuyang is one of the typical cities being involved but its epidemiological characteristics of diabetes is not clear. In this study, 4131 adults in randomly selected families from all the townships and streets of Fuyang were investigated. This study showed that the standardized prevalence of diabetes was 8.10 % in Fuyang. The prevalence of prediabetes was 11.3 %. The prevalence of isolated impaired glucose tolerance (IGT) was 10.51 %. The prevalence of diabetes in urban areas was slightly higher than that of rural areas (14.3 % vs. 13.0 %). The prevalence of prediabetes in urban areas was also higher than that of rural areas (19.1 % vs. 15.6 %). Among all the patients diagnosed with diabetes, 46.02 % of them received treatment. Age, family history of diabetes, obesity, high level of triglyceride, and low-density lipoprotein were risk factors of diabetes.     

Targeted screening for prediabetes and undiagnosed diabetes in a community setting in India

Background and objectivesData to support the use of risk scores in screening programs to detect people with prediabetes and undiagnosed diabetes in low- and middle-income countries are limited. We evaluated a targeted screening program involving a diabetes risk score in a community setting in India in terms of its uptake, yield, and costs.MethodsIn the Kerala Diabetes Prevention Program, 2586 individuals (age 30–60 years) without known diabetes were screened using a two-step procedure. Step 1: screening with the Indian Diabetes Risk Score at participants’ homes by trained non-medical staff. Step 2: oral glucose tolerance test (OGTT) among those with IDRS score ≥60 (“screen-positive”) at community-based clinics. Screening costs were expressed in 2013 US dollars.Results96.3% of those invited for the IDRS screening consented and 79.1% of screen-positives attended clinics for an OGTT. Older age and male gender were associated with higher IDRS uptake. Female gender, higher monthly household expenditure, and higher IDRS score were associated with higher OGTT uptake. The number needed to screen (yield) to detect one person with prediabetes and undiagnosed diabetes was two and six, respectively. The average screening cost of identifying one person with prediabetes and undiagnosed diabetes was $33.8 and $116.5, respectively.ConclusionThis targeted screening program had a high uptake and high yield for prediabetes and undiagnosed diabetes in a community setting in India. Alternative strategies are likely required to enhance the uptake of screening in certain groups.     

Comparison of the prevalence of metabolic syndrome and its association with diabetes and cardiovascular disease in the rural population of Bangladesh using the modified National Cholesterol Education Program Expert Panel Adult Treatment Panel III and International Diabetes Federation definitions

Aims/Introduction

To compare the prevalence of metabolic syndrome (MS) using the modified National Cholesterol Education Program Adult Treatment Plan III (NCEP) and the International Diabetes Federation (IDF) definitions and, using both definitions, determine and compare the association of MS, prediabetes, type 2 diabetes, hypertension (HTN) and cardiovascular disease risk (CVD).

Materials and Methods

A total of 2,293 randomly selected participants (aged ≥20 years) in a rural community in Bangladesh were investigated in a population-based cross-sectional study. Sociodemographic and anthropometric characteristics, blood pressure, blood glucose, and lipid profiles were studied. Age-adjusted data for MS and cardiometabolic risk factors were assessed, and their relationships were examined.

Results

The age-adjusted prevalence of MS was 30.7% (males 30.5%; females 30.5%) using the NCEP definition, and 24.5% (males 19.2%, females 27.5%) using the IDF definition. The prevalence of MS using the NCEP definition was also higher in study participants with prediabetes, type 2 diabetes, HTN and CVD risk. The agreement rate between both definitions was 92% (k = 0.80). The NCEP definition had a stronger association with type 2 diabetes and HTN (odds ratio 12.4 vs 5.2; odds ratio 7.0 vs 4.7, respectively) than the IDF definition. However, the odds ratios for prediabetes and CVD risk were not significantly different.

Conclusions

The prevalence of MS was higher using the NCEP definition, and was more strongly associated with prediabetes, type 2 diabetes, HTN and CVD in this Bangladeshi population.     

Cardiometabolic Risk Profiles in Patients With Impaired Fasting Glucose and/or Hemoglobin A1c 5.7% to 6.4%: Evidence for a Gradient According to Diagnostic Criteria: The PREDAPS Study

It has been suggested that the early detection of individuals with prediabetes can help prevent cardiovascular diseases. The purpose of the current study was to examine the cardiometabolic risk profile in patients with prediabetes according to fasting plasma glucose (FPG) and/or hemoglobin A1c (HbA1c) criteria.Cross-sectional analysis from the 2022 patients in the Cohort study in Primary Health Care on the Evolution of Patients with Prediabetes (PREDAPS Study) was developed. Four glycemic status groups were defined based on American Diabetes Association criteria. Information about cardiovascular risk factors–body mass index, waist circumference, blood pressure, cholesterol, triglycerides, uric acid, gamma-glutamyltransferase, glomerular filtration–and metabolic syndrome components were analyzed. Mean values of clinical and biochemical characteristics and frequencies of metabolic syndrome were estimated adjusting by age, sex, educational level, and family history of diabetes.A linear trend (P < 0.001) was observed in most of the cardiovascular risk factors and in all components of metabolic syndrome. Normoglycemic individuals had the best values, individuals with both criteria of prediabetes had the worst, and individuals with only one–HbA1c or FPG–criterion had an intermediate position. Metabolic syndrome was present in 15.0% (95% confidence interval: 12.6–17.4), 59.5% (54.0–64.9), 62.0% (56.0–68.0), and 76.2% (72.8–79.6) of individuals classified in normoglycemia, isolated HbA1c, isolated FPG, and both criteria groups, respectively.In conclusion, individuals with prediabetes, especially those with both criteria, have worse cardiometabolic risk profile than normoglycemic individuals. These results suggest the need to use both criteria in the clinical practice to identify those individuals with the highest cardiovascular risk, in order to offer them special attention with intensive lifestyle intervention programs.     

Serum potassium is associated with prediabetes and newly diagnosed diabetes in hypertensive adults from the general population: The KORA F4-Study

Aims/hypothesis

Evidence suggests that low serum potassium concentrations or hypokalaemia induced by the intake of diuretics are associated with incident diabetes and increased risk for diabetes in persons with hypertension. We examined a possible association between serum potassium and prediabetes (defined as isolated impaired fasting glucose [i-IFG], isolated impaired glucose tolerance [i-IGT] or combined IFG/IGT), as well as known and newly diagnosed diabetes (NDD), in 32- to 81-year-old men and women with and without hypertension.

Methods

This cross-sectional analysis was based on 2,948 participants in the Cooperative Health Research in the Region of Augsburg (KORA) F4 study conducted in 2006–2008 in southern Germany. Serum concentrations of potassium were measured by indirect potentiometry.

Results

In the total sample there was no association between serum potassium concentrations and prediabetes. In hypertensive persons however serum potassium levels in the first and second quartile compared with the highest quartile were independently significantly associated with prediabetes after multivariable adjustment (OR for prediabetes, 2.02 [95% CI 1.27, 3.21] for quartile 2 and 2.00 [95% CI 1.27, 3.15] for quartile 1), while in persons without hypertension no association was found. In multinomial logistic regression analysis these findings could be confirmed. In hypertensive participants after multivariable adjustment the associations were statistically significant for i-IGT and NDD (i-IGT OR 1.23; NDD OR 1.41). However, in non-hypertensive persons, all associations between serum potassium levels and each of the categories of impaired glucose regulation were non-significant.

Conclusions/interpretation

Serum potassium levels were independently associated with prediabetes and NDD in hypertensive adults from the general population.     

Progression rates from HbA1c 6.0–6.4% and other prediabetes definitions to type 2 diabetes: a meta-analysis

Aims/hypothesis

Precise estimates of progression rates from ‘prediabetes’ to type 2 diabetes are needed to optimise prevention strategies for high-risk individuals. There is acceptance of prediabetes defined by impaired fasting glucose (IFG) and impaired glucose tolerance (IGT), but there is some controversy surrounding HbA_1c-defined prediabetes ranges, with some favouring 6.0–6.4% (42–46 mmol/mol). Comparing progression rates between groups might aid this issue, thus we aimed to accurately estimate progression rates to diabetes from different prediabetes categories.

Methods

Meta-analysis of prospective observational studies in which participants had prediabetes at baseline (ADA-defined IFG [5.6–6.9 mmol/l], WHO-defined IFG [6.1–6.9 mmol/l], IGT (7.8–11.0 mmol/l) or raised HbA_1c [6.0–6.4%/42–46 mmol/mol]) and were followed up for incident diabetes. Incidence rates were combined using Bayesian random effects models.

Results

Overall, 70 studies met the inclusion criteria. In the six studies that used raised HbA_1c, the pooled incidence rate (95% credible interval) of diabetes was 35.6 (15.1, 83.0) per 1,000 person-years. This rate was most similar to that for ADA-defined IFG (11 studies; 35.5 [26.6, 48.0]) and was non-significantly lower than WHO-defined IFG (34 studies; 47.4 [37.4, 59.8]), IGT (46 studies, 45.5 [37.8, 54.5]) and IFG plus IGT (15 studies, 70.4 [53.8, 89.7]). Similar results were seen when the data were analysed by the criteria used to diagnose diabetes.

Conclusions/interpretation

This study provides evidence that progression rates differ by prediabetes definition, which has implications for the planning and implementation of diabetes prevention programmes. HbA_1c 6.0–6.4% might identify people at a lower diabetes risk than other prediabetes definitions, but further research is needed.