Impaired glucose metabolism among those with and without diagnosed diabetes and mortality: a cohort study using Health Survey for England data

HbA1c and fasting plasma glucose levels are equally related to incident cardiovascular risk in a high CVD risk population without known diabetes

OBJECTIVES

Type 2 diabetes (T2DM) is associated with increased risk for cardiovascular disease (CVD). Whether screen-detected T2DM, based on fasting plasma glucose (FPG) or on HbA1c, are associated with different risks of incident CVD in high-risk populations and which one is preferable for diabetes screening in these populations, remains unclear.

METHODS

A total of 8,274 high-risk CVD participants were included from the UCC-SMART cohort. Participants were divided into groups based on prior T2DM diagnosis, and combinations of elevated/non-elevated FPG and HbA1c (cut-offs at 7 mmol/L and 48 mmol/mol, respectively): Group 0: known T2DM; group 1: elevated FPG/HbA1c; group 2: elevated FPG, non-elevated HbA1c; group 3: non-elevated FPG, elevated HbA1c; group 1 + 2: elevated FPG, regardless of HbA1c; group 1 + 3: elevated HbA1c, regardless of FPG; and group 4 (reference), non-elevated FPG/HbA1c.

RESULTS

During a median follow-up of 6.3 years (IQR 3.3-9.8), 712 cardiovascular events occurred. Compared to the reference (group 4), group 0 was at increased risk (HR 1.40; 95 % CI 1.16-1.68), but group 1 (HR 1.16; 95 % CI 0.62-2.18), 2 (HR 1.18; 95 % CI 0.84-1.67), 3 (HR 0.61; 95 % CI 0.15-2.44), 1 + 2 (HR 1.17; 95 % CI 0.86-1.59) and 1 + 3 (HR 1.01; 95 % CI 0.57-1.79) were not. However, spline interpolation showed a linearly increasing risk with increasing HbA1c/FPG, but did not allow for identification of other cut-off points.

CONCLUSIONS

Based on current cut-offs, FPG and HbA1c at screening were equally related to incident CVD in high-risk populations without known T2DM. Hence, neither FPG, nor HbA1c, is preferential for diabetes screening in this population with respect to risk of incident CVD.

NT-proBNP and cardiovascular event risk in individuals with prediabetes undergoing cardiovascular evaluation

AIMS

Cardiovascular risk assessment beyond traditional risk factors in subjects with prediabetes is not well-established. Here, we evaluated the utility of N-terminal pro-B-type natriuretic peptide (NT-proBNP) in predicting incident adverse cardiovascular outcomes in prediabetic subjects.

METHODS

NT-proBNP was analyzed in 3,235 stable subjects with prediabetes undergoing cardiovascular risk evaluation and followed for both 3-year major adverse cardiac events (MACE; death, myocardial infarction, stroke), and 5-year all-cause mortality.

RESULTS

Using Cox proportional hazard models, we found that plasma NT-proBNP was associated with incident (3-year) MACE risk (Q4 vs Q1, HR 6.04 [95%CI 4.17-8.76], P < 0.001) and 5-year mortality risk (HR 8.64 [95%CI 5.78-12.9], P < 0.001). These associations remained significant after adjustments for traditional cardiovascular risk factors, multiple indices of glycemic control, cardiovascular disease (CVD), left ventricular ejection fraction (LVEF), and medication (e.g. diuretic) use (adjusted HR for 3-year MACE 2.65 [95% CI 1.16-6.05], P < 0.05; and adjusted HR for 5-year mortality 3.45 [95% CI 1.42-8.39], P < 0.01). NT-proBNP significantly improved the clinical prognostic value (C-statistic, NRI, IDI) for both 3-year MACE and 5-year death when added to models.

CONCLUSIONS

NT-proBNP independently predicts increased long-term MACE and mortality risks in prediabetic subjects, and may help identify those for whom more aggressive global preventive efforts are indicated.

Prognostic value of subclinical myocardial necrosis using high-sensitivity cardiac troponin T in patients with prediabetes

BACKGROUND

Risk stratification of patients with prediabetes is an unmet clinical need. Here, we examine the utility of subclinical myocardial necrosis assessed by high-sensitivity cardiac troponin T (hs-cTnT) in predicting health outcomes in stable subjects with prediabetes.

METHODS

hs-cTnT was analyzed by a high-sensitivity assay (Roche 5th generation) in 2631 stable subjects with prediabetes (HbA1c 5.7-6.4% or fasting glucose 100-125 mg/dL without previous diagnosis of diabetes or glucose-lowering therapy) who underwent elective coronary angiography for cardiac evaluation, and followed for major adverse cardiac events (MACE; death, myocardial infarction, stroke) over 3 years and all-cause mortality over 5 years.

RESULTS

In our study cohort, hs-cTnT was highly prevalent with a median level of 13 ng/L (interquartile range 8.2-21.6 ng/L). Hs-cTnT was independently associated with incident MACE at 3 years (Q4 vs. Q1 adjusted hazard ratio (HR) 2.42 [95% CI 1.69-3.46], P < 0.001) and 5-year mortality (adjusted HR 3.8 [95% CI 2.55-5.67], P < 0.001). This association remained significant in all subsets after adjustment for traditional risk factors and multiple factors known to increase hs-cTnT levels. Moreover, hs-cTnT independently predicted event risk in primary prevention subjects (n = 557, HR 5.46 [95% CI 1.50-19.89), p < 0.01) for MACE; HR 9.53 [95% CI 2.08-43.73] for all-cause mortality) and secondary prevention subjects (n = 2074, HR 1.86 [95% CI 1.31-2.66], P < 0.001 for MACE; and 2.7 [95% CI 1.79-4.08), P < 0.001 for all-cause mortality).

CONCLUSIONS

In stable prediabetic subjects, the presence of subclinical myocardial necrosis as detected by hs-cTnT portends heightened long-term adverse cardiovascular event risk. Hs-cTnT levels may help to stratify risk and improve clinical decision making in patients with prediabetes. Trial registration ClinicalTrials.gov Identifier: NCT00590200.

Associations between haemoglobin A1c and mortality rate in the KORA S4 and the Heinz Nixdorf Recall population-based cohort studies

BACKGROUND

There is limited knowledge about mortality risk in persons with increased haemoglobin A_1c (HbA_1c ) levels below the diabetes threshold. Moreover, little is known about how associations between increased HbA_1c and mortality depend on the length of follow-up. Therefore, we studied associations between HbA_1c and mortality over long-term follow-up in persons with and without known diabetes.

METHODS

We used data from two German population-based cohort studies: KORA S4 Study (Southern Germany, n = 1458, baseline visits in 1999 to 2001, baseline age 55 to 74 years, mortality follow-up 16.8 years) and Heinz Nixdorf Recall (HNR) Study (Ruhr area, n = 4613, baseline visits in 2000 to 2003, baseline age 45 to 75 years, mortality follow-up 17.8 years). Adjusted log-linear models were fitted to estimate relative risks (RRs) with 95% confidence intervals (CI).

RESULTS

In both cohorts, participants with HbA_1c 39 to 41 mmol/mol (5.7%-5.9%) and HbA_1c 42 to 46 mmol/mol (6.0% to 6.4%) did not have a larger overall mortality risk than participants with HbA_1c  < 39 mmol/mol (5.7%): the corresponding adjusted RRs were 1.00 (95% CI: 0.83-1.21) and 1.01 (0.80-1.27) in KORA and 0.99 (0.82-1.21) and 0.83 (0.65-1.07) in the HNR Study. For the pooled cohorts, the RR for HbA_1c 39 to 46 mmol/mol (5.7%-6.4%) was 0.96 (0.85-1.07). Associations between newly detected diabetes (HbA_1c  ≥ 6.5%) and mortality were weak after 4 and 8 years of follow-up, but were stronger after 12 years of follow-up, whereas associations between previously known diabetes (baseline) and mortality decreased.

CONCLUSIONS

HbA_1c -defined pre-diabetes is not associated with overall mortality. For newly detected and previously known diabetes, mortality risks vary with length of follow-up.

Diabetes, Glycated Hemoglobin, and the Risk of Myocardial Infarction in Women and Men: A Prospective Cohort Study of the UK Biobank

OBJECTIVE

Diabetes has shown to be a stronger risk factor for myocardial infarction (MI) in women than men. Whether sex differences exist across the glycemic spectrum is unknown. We investigated sex differences in the associations of diabetes status and glycated hemoglobin (HbA1c) with the risk of MI.

RESEARCH DESIGN AND METHODS

Data were used from 471,399 (56% women) individuals without cardiovascular disease (CVD) included in the UK Biobank. Sex-specific incidence rates were calculated by diabetes status and across levels of HbA1c using Poisson regression. Cox proportional hazards analyses estimated sex-specific hazard ratios (HRs) and women-to-men ratios by diabetes status and HbA1c for MI during a mean follow-up of 9 years.

RESULTS

Women had lower incidence rates of MI than men, regardless of diabetes status or HbA1c level. Compared with individuals without diabetes, prediabetes, undiagnosed diabetes, and previously diagnosed diabetes were associated with an increased risk of MI in both sexes. Previously diagnosed diabetes was more strongly associated with MI in women (HR 2.33 [95% CI 1.96; 2.78]) than men (1.81 [1.63; 2.02]), with a women-to-men ratio of HRs of 1.29 (1.05; 1.58). Each 1% higher HbA1c, independent of diabetes status, was associated with an 18% greater risk of MI in both women and men.

CONCLUSIONS

Although the incidence of MI was higher in men than women, the presence of diabetes is associated with a greater excess relative risk of MI in women. However, each 1% higher HbA1c was associated with an 18% greater risk of MI in both women and men.

Impaired Fasting Glucose and Chronic Kidney Disease, Albuminuria, or Worsening Kidney Function: a Secondary Analysis of the SPRINT

PURPOSE

Diabetes mellitus is a risk factor for the development and progression of chronic kidney disease (CKD). However, the association of prediabetes with adverse kidney outcomes is uncertain.

METHODS

We performed a secondary analysis of the Systolic Blood Pressure Intervention Trial (SPRINT), including 9,361 participants without diabetes at baseline. We categorized participants according to fasting glucose as having impaired fasting glucose (≥100 mg/dL [(≥5.6 mmol/L]) or normoglycemia (<100 mg/dL [(<5.6 mmol/L]). Unadjusted and adjusted proportional hazards models were fit to estimate the association of impaired fasting glucose (versus normoglycemia) with a composite outcome of worsening kidney function (≥30% decrease in eGFR to <60 ml/min/1.73 m2 in participants without baseline CKD; ≥50% decrease in eGFR or need of long-term dialysis/kidney transplantation in participants with CKD) or incident albuminuria (doubling of urinary albumin to creatinine ratio from <10 mg/g to >10 mg/g). These outcomes were also evaluated separately, and according to CKD status at baseline.

RESULTS

The mean age was 67.9 ± 9.4 years, 35.5% were female, and 31.4% were black. The median follow-up was 3.3 years and 41.8% had impaired fasting glucose. Impaired fasting glucose was not associated with higher rates of the composite outcome (HR 0.97; 95%CI 0.81-1.16), worsening kidney function (HR 1.02; 95%CI 0.75-1.37), or albuminuria (HR 0.98; 95%CI 0.78-1.23). Similarly, there was no association of impaired fasting glucose with outcomes according to baseline CKD status.

CONCLUSIONS

Impaired fasting glucose at baseline was not associated with the development of worsening kidney function or albuminuria in participants of SPRINT.

Mortality risk in adults according to categories of impaired glucose metabolism after 18 years of follow-up in the North of Spain: The Asturias Study

People who develop type 2 diabetes (T2D) are known to have a higher mortality risk. We estimated all-cause, cardiovascular, and cancer mortality-risks in our patient cohort according to categories of impaired glucose metabolism. This 18-year retrospective analysis included a region-wide, representative sample of a population aged 30-75 years. Age- and sex-stratified hazard ratios (HRs) were calculated for 48 participants with diagnosed T2D, 83 with undiagnosed T2D (HbA1c ≥6.5%, fasting glycemia ≥126 mg/dL, or glycemia after 75 g glucose load ≥200 mg/dL); 296 with prediabetes (HbA1c 5.7%-6.4%, fasting glycemia 100-125 mg/dL, or glycemia after 75 g glucose load 140-199 mg/dL), and 607 with normoglycemia. Over 18,612 person-years, 32 individuals with undiagnosed T2D, 30 with diagnosed T2D, 62 with prediabetes, and 80 with normoglycemia died. Total sample crude mortality rate (MR) was 10.96 deaths per 1,000 person-years of follow-up. MR of the diagnosed T2D group was more than 3-times higher and that of newly diagnosed T2D was 2-times higher (34.72 and 21.42, respectively) than total sample MR. Adjusted HR for all-cause mortality was 2.02 (95% confidence interval 1.29-3.16) and 1.57 (95% CI 1.00-2.28) in the diagnosed T2D group and the newly diagnosed T2D group, respectively. Adjusted HR for cardiovascular mortality in the T2D group was 2.79 (95% CI 1.35-5.75); this risk was greatly increased in women with T2D: 6.72 (95% CI 2.50-18.07). In Asturias, age- and sex-standardized all-cause mortality is more than 2-times higher for adults with T2D than for adults without T2D. The HR for cardiovascular mortality is considerably higher in T2D women than in normoglycemic women.

Cancer incidence among Finnish people with type 2 diabetes during 1989-2014

Diabetes and cancer are common diseases both with enormous impact on health burden globally. The increased risk of several types of cancer among people with type 2 diabetes mellitus has been indicated repeatedly. This study aimed at exploring and describing the association between type 2 diabetes and cancer incidence. A cohort of 428,326 people with type 2 diabetes was identified from the Finnish National Diabetes Register and followed up through a register linkage with the Finnish Cancer Registry for cancer incidence during 1988-2014. A total of 74,063 cases of cancer occurred in this cohort in 4.48 million person-years. This accounted for 16% more than the expected cancer incidence in the Finnish general population; the standardized incidence ratio (SIR) was 1.16 (95% confidence interval [CI] 1.15-1.16). There was a statistically significant excess of cancers of lip (SIR = 1.40, CI = 1.28-1.53), liver (SIR = 2.44, CI = 2.35-2.53), pancreas (SIR = 1.75, CI = 1.70-1.79), stomach (SIR = 1.22, CI = 1.18-1.26), colon (SIR = 1.22, CI = 1.19-1.25), gallbladder and bile ducts (SIR = 1.29, CI = 1.21-1.36), non-melanoma skin (SIR = 1.18, CI = 1.15-1.22), kidney (SIR = 1.42, CI = 1.37-1.47), bladder (SIR = 1.17, CI = 1.13-1.21), and thyroid (SIR = 1.22, CI = 1.12-1.31). There was a small statistically significant decrease in prostate cancer incidence (SIR = 0.95, CI = 0.93-0.96). This study showed an association between type 2 diabetes mellitus and the incidence of cancer at numerous sites in the Finnish population.

Comparison of surveillance-based metrics for the assessment and monitoring of disease detection: simulation study about type 2 diabetes

Background

Screening and detection of cases are a common public health priority for treatable chronic conditions with long subclinical periods. However, the validity of commonly-used metrics from surveillance systems for rates of detection (or case-finding) have not been evaluated.

Methods

Using data from a Danish diabetes register and a recently developed illness-death model of chronic diseases with subclinical conditions, we simulate two scenarios of different performance of case-finding. We report different epidemiological indices to assess case-finding in both scenarios and compare the validity of the results.

Results

The commonly used ratio of detected cases over total cases may lead to misleading conclusions. Instead, the ratio of undetected cases over persons without a diagnosis is a more valid index to distinguish the quality of case-finding. However, incidence-based measures are preferable to prevalence based indicators.

Conclusion

Prevalence-based indices for assessing case-finding should be interpreted with caution. If possible, incidence-based indices should be preferred.

Electronic supplementary material

The online version of this article (doi:10.1186/s12874-017-0328-2) contains supplementary material, which is available to authorized users.

Association between prediabetes and risk of cardiovascular disease and all cause mortality: systematic review and meta-analysis

OBJECTIVES

 To evaluate associations between different definitions of prediabetes and the risk of cardiovascular disease and all cause mortality.

DESIGN

 Meta-analysis of prospective cohort studies.

DATA SOURCES

 Electronic databases (PubMed, Embase, and Google Scholar).

SELECTION CRITERIA

 Prospective cohort studies from general populations were included for meta-analysis if they reported adjusted relative risks with 95% confidence intervals for associations between the risk of composite cardiovascular disease, coronary heart disease, stroke, all cause mortality, and prediabetes.

REVIEW METHODS

 Two authors independently reviewed and selected eligible studies, based on predetermined selection criteria. Prediabetes was defined as impaired fasting glucose according to the criteria of the American Diabetes Association (IFG-ADA; fasting glucose 5.6-6.9 mmol/L), the WHO expert group (IFG-WHO; fasting glucose 6.1-6.9 mmol/L), impaired glucose tolerance (2 hour plasma glucose concentration 7.8-11.0 mmol/L during an oral glucose tolerance test), or raised haemoglobin A_1c (HbA_1c) of 39-47 mmol/mol : (5.7-6.4%) according to ADA criteria or 42-47 mmol/mol (6.0-6.4%) according to the National Institute for Health and Care Excellence (NICE) guideline. The relative risks of all cause mortality and cardiovascular events were calculated and reported with 95% confidence intervals.

RESULTS

 53 prospective cohort studies with 1 611 339 individuals were included for analysis. The median follow-up duration was 9.5 years. Compared with normoglycaemia, prediabetes (impaired glucose tolerance or impaired fasting glucose according to IFG-ADA or IFG-WHO criteria) was associated with an increased risk of composite cardiovascular disease (relative risk 1.13, 1.26, and 1.30 for IFG-ADA, IFG-WHO, and impaired glucose tolerance, respectively), coronary heart disease (1.10, 1.18, and 1.20, respectively), stroke (1.06, 1.17, and 1.20, respectively), and all cause mortality (1.13, 1.13 and 1.32, respectively). Increases in HBA_1c to 39-47 mmol/mol or 42-47 mmol/mol were both associated with an increased risk of composite cardiovascular disease (1.21 and 1.25, respectively) and coronary heart disease (1.15 and 1.28, respectively), but not with an increased risk of stroke and all cause mortality.

CONCLUSIONS

 Prediabetes, defined as impaired glucose tolerance, impaired fasting glucose, or raised HbA_1c, was associated with an increased risk of cardiovascular disease. The health risk might be increased in people with a fasting glucose concentration as low as 5.6 mmol/L or HbA_1c of 39 mmol/mol.

Methods, units and quality requirements for the analysis of haemoglobin A1c in diabetes mellitus

The formation of glycohemoglobin, especially the hemoglobin A_1c (HbA_1c) fraction, occurs when glucose becomes coupled with the amino acid valine in the β-chain of Hb; this reaction is dependent on the plasma concentration of glucose. Since the early 1970s it has been known that diabetics display higher values OF HbA_1C because they have elevated blood glucose concentrations. Thus HbA_1c has acquired a very important role in the treatment and diagnosis of diabetes mellitus. After the introduction of the first quantitative measurement OF HbA_1C, numerous methods for glycohemoglobin have been introduced with different assay principles: From a simple mini-column technique to the very accurate automated high-pressure chromatography and lastly to many automated immunochemical or enzymatic assays. In early days, the results of the quality control reports for HbA_1c varied extensively between laboratories, therefore in United States and Canada working groups (WG) of the Diabetes Controls and Complications Trial (DCCT) were set up to standardize the HbA_1c assays against the DCCT/National Glycohemoglobin Standardization Program reference method based on liquid chromatography. In the 1990s, the International Federation of Clinical Chemistry and Laboratory Medicine (IFCC) appointed a new WG to plan a reference preparation and method for the HBA_1c measurement. When the reference procedures were established, in 2004 IFCC recommended that all manufacturers for equipment used in HbA_1c assays should calibrate their methods to their proposals. This led to an improvement in the coefficient of variation (CV%) associated with the assay. In this review, we describe the glycation of Hb, methods, standardization of the HbA_1c assays, analytical problems, problems with the units in which HbA_1c values are expressed, reference values, quality control aspects, target requirements for HbA_1c, and the relationship of the plasma glucose values to HbA_1c concentrations. We also note that the acceptance of the mmol/mol system for HbA_1c as recommended by IFCC, i.e., the new unit and reference ranges, are becoming only slowly accepted outside of Europe where it seems that expressing HbA_1c values either only in per cent units or with parallel reporting of percent and mmol/mol will continue. We believe that these issues should be resolved in the future and that it would avoid confusion if mmol/mol unit for HbA_1c were to gain worldwide acceptance.

Mortality in Individuals Aged 80 and Older with Type 2 Diabetes Mellitus in Relation to Glycosylated Hemoglobin, Blood Pressure, and Total Cholesterol

Objectives

To evaluate whether low glycosylated hemoglobin (HbA1c), blood pressure (BP), and total cholesterol (TC) are associated with lower risk of all‐cause mortality in very old individuals with type 2 diabetes mellitus.

Design

Population‐based cohort study.

Setting

Primary care database in the United Kingdom.

Participants

Individuals aged 80 and older with type 2 diabetes mellitus (N = 25,966).

Measurements

Associations between baseline HbA1c, BP, and TC and all‐cause mortality were evaluated in Cox proportional hazards models. Analyses were adjusted for sex, age, duration of diabetes mellitus, lifestyle variables, HbA1c, BP, TC, comorbidities, prescribing of antidiabetic and cardiovascular drugs, and participants’ general practice.

Results

There were 4,490 deaths during follow‐up (median 2.0 years; mortality 104.7 per 1,000 person‐years). Mortality in participants with low (<6.0% (<42 mmol/mol)) or high (≥8.5% (≥69 mmol/mol)) HbA1c was similar to that in those with the reference HbA1c (8.0–8.4% (64–68 mmol/mol)). Mortality was lowest in individuals with HbA1c of 7.0–7.4% (53–57 mmol/mol) (80.9 per 1,000 person‐years, adjusted hazard ratio (aHR) = 0.80, 95% confidence interval (CI) = 0.70–0.91, P = .001). Mortality was higher in individuals with lower BP (e.g., <130/70 mmHg, 151.7 per 1,000 person‐years, aHR = 1.52, 95% CI = 1.34–1.72, P < .001 vs reference BP <150/90 mmHg) and in the lowest TC category (<3.0 mmol/L, 138.7 per 1,000 person‐years, aHR = 1.42, 95% CI = 1.24–1.64, P < .001 vs reference TC 4.5–4.9 mmol/L). The relationship between TC and mortality varied according to sex and prescription of lipid‐lowering drugs.

Conclusion

Low HbA1c, BP, and TC may be associated with higher mortality in very old adults with type 2 diabetes mellitus. Further research is required to understand these associations and to identify optimal treatment targets in this population.

Determinants of mortality in patients with type 2 diabetes: a review

We aimed to review and summarize the evidence from accomplished trials analyzing factors influencing mortality in patients with T2DM and to provide some recommendations for targets and treatment in the European region. The following databases were searched for relevant trials: PubMed and the Cochrane Library. Of 3.806 citations, 134 trials met our inclusion criteria.

RESULTS

The reduction in lifetime for 65 + -years-old patients having less than 10 years T2DM amounts to 1.8 years. Having T2DM for more than 10 years lifetime will be reduced by 2.7 years. However, the lifetime shortening factor of T2DM will even be stronger for 40 + -years-old patients at onset. Males will lose 11.6 years of life and 18.6 QUALYs. T2DM among females will reduce life by 14 QUALYs by 22 years. From a statistical point of view, the highest mortality rate will occur in an over 55-years-old European smoking and non-compliant diabetic woman with alcohol abuse living in a rural area with a low level of education and a low socio-economic status. Furthermore, other co-morbidities such as cardiovascular diseases, gout, and depression affect mortality. Additionally, mortality will increase with a BMI over 35 and also with a BMI under 20-25. This refers to the obesity paradox indicating a higher mortality rate among normal weight patients with T2DM compared to overweight patients with T2DM. HbA1c-levels between 6.5 % and 7 % are associated with the lowest impact on mortality.

Baseline glycemic status and mortality in 241,499 Korean metropolitan subjects: A Kangbuk Samsung Health Study

OBJECTIVE

Diabetes and prediabetes subjects have increased risk for mortality. We analyzed the mortality risk due to all causes, cardiovascular disease (CVD) and cancer in Korean subjects participating in a health-screening program according to baseline glycemic status and HbA1c levels.

MATERIALS/METHODS

Among 241,499 participants of a health-screening program between 2005 and 2012, the risk of death from all causes, CVD, and cancer was calculated based on the baseline glycemic status (normoglycemia, prediabetes, and diabetes) and HbA1c levels. Uncontrolled diabetes was defined as HbA1c≥7.0%. Vital status and confirmation of the cause of death were based on the analysis of death certificate records from the National Death Index.

RESULTS

During 923,343.1 person-years of follow-up, 877 participants died. The multivariable-adjusted hazard ratios (HR) of subjects with controlled and uncontrolled diabetes to normoglycemic subjects for all-cause mortality were 1.58 (95% CI 1.24-2.03) and 2.26 (95% CI 1.78-2.86), respectively. The HRs of subjects with controlled and uncontrolled diabetes to normoglycemic subjects for mortality due to cancer were 1.75 (95% CI 1.23-2.48) and 1.67 (95% CI 1.13-2.45). However, glycemic status was not significantly associated with the risk of mortality due to CVD. The subjects with HbA1c higher than 6.5% showed more than 2-fold increased risk for all-cause mortality and the subjects with HbA1c lower than 5.2% showed increased HR (1.45, 95% CI 1.06-1.97) compared with those with HbA1c of 5.5% in subjects not taking anti-diabetic medications.

CONCLUSIONS

Mortality risk from all causes and cancer significantly increased in diabetes subjects regardless of the glucose control status. In subjects not taking anti-diabetic medications, both high and low HbA1c resulted in increased risk for all-cause mortality.

Associations between Metabolic Risk Factors and the Hypothalamic Volume in Childhood Leukemia Survivors Treated with Cranial Radiotherapy

Metabolic complications are prevalent in individuals treated with cranial radiotherapy (CRT) for childhood acute lymphoblastic leukemia (ALL). The hypothalamus is a master regulator of endocrine and metabolic control. The aim of this study was to investigate whether the hypothalamic volume would be associated to metabolic parameters in ALL survivors. Thirty-eight (21 women) survivors participated in this study 34 years after diagnosis and with a median age of 38 (27–46) years. All were treated with a median CRT dose of 24 Gy and 11 years (3–13) of complete hormone supplementation. Comparisons were made to 31 matched controls. We performed analyses of fat mass, fat free mass, plasma (p)-glucose, p-insulin, Homa-Index (a measure of insulin resistance), serum (s)-leptin, s-ghrelin and of the hypothalamic volume in scans obtained by magnetic resonance imaging (MRI) at 3 Tesla. Serum leptin/kg fat mass (r = -0.4, P = 0.04) and fat mass (r = -0.4, P = 0.01) were negatively correlated with the HT volume among ALL survivors, but not among controls. We also detected significantly higher BMI, waist, fat mass, p-insulin, Homa-Index, leptin/kg fat mass and s-ghrelin and significantly lower fat free mass specifically among female ALL survivors (all P<0.01). Interestingly, s-ghrelin levels increased with time since diagnosis and with low age at diagnosis for childhood ALL. Our results showed that leptin/kg fat mass and fat mass were associated with a reduced HT volume 34 years after ALL diagnosis and that women treated with CRT after ALL are at high risk of metabolic abnormalities. Taken together our data suggest that the hypothalamus is involved in the metabolic consequences after CRT in ALL survivors.