Diabetic retinopathy in well-controlled type 2 diabetes: Role of glycaemic memory.

AIMS: As diabetic retinopathy (DR) can occur even in well-controlled patients with type 2 diabetes (T2D), our study sought to determine whether it might be related to 'glucose memory' by evaluating patients' HbA1c over previous years and their skin autofluorescence (SAF). METHODS: In 334 patients with T2D and HbA1c levels≤8%, their available values of HbA1c from previous years were collected, and their SAF measured by an advanced glycation end-product (AGE) reader. Binary logistic regression analysis was then used to correlate DR with previously recorded HbA1c levels and to SAF, with adjustment for DR risk factors [age, gender, BMI, duration of diabetes, arterial hypertension, diabetic kidney disease (DKD), blood lipid levels and statin treatment]. RESULTS: Our patients were mostly men (58.4%) aged 63±10years, with a duration of diabetes of 13±10years and HbA1c=7.1±0.7%. Of these patients, 84 (25.1%) had DR, which was associated with longer duration of diabetes and greater prevalence of DKD. A total of 605 HbA1c values from previous years were collected for time periods -4±3 months (n=255), -16±4months (n=152), -30±4months (n=93) and -62±26 months (n=105). After adjustment, the association between DR and having an HbA1c higher than the median was significant only for the oldest previous HbA1c values: OR=6.75, 95% CI: 1.90-23.90. Moreover, SAF values were higher in those with DR [2.95±0.67 arbitrary units (AU)] vs 2.65±0.65 AU with no DR (P<0.01) and were also associated with the oldest previous HbA1c values (P<0.01). CONCLUSION: Our study found that 25.1% of our well-controlled T2D patients had DR, which was related to both their HbA1c levels from 5years prior to study admission and their SAF values, a marker of glucose memory.

Serum fructosamine predicts macrosomia in well-controlled hyperglycaemic pregnant women: An observational cross-sectional study.

AIM: While serum fructosamine may be a good marker of glucose control in pregnant women with diabetes, its relationship with macrosomia is still uncertain. METHODS: In 130 hyperglycaemic women with singleton pregnancies (117 gestational diabetes mellitus, 13 pregestational diabetes), serum fructosamine and HbA1c levels were measured at 25±7 weeks of gestation. Levels in mothers of infants with and without macrosomic newborns (birth weight>4000g and/or large-for-gestational-age birth weight>90th percentile) were compared using logistic regression analysis adjusted for macrosomia risk factors. RESULTS: These 130 pregnant women were 33±5 years old; their BMI before pregnancy was 27.7±6.9kg/m2, and they gained 7.5±5.1kg during the first 6 months of gestation. Glucose control was good according to HbA1c levels (5.3±0.3%; 34±2mmol/mol), yet 17/130 (13%) newborns had macrosomia: 3900±227g vs 3057±512g (P<0.001) in the others. These mothers were older and had higher parity, whereas their BMI scores before pregnancy and gestational weight gains did not differ. Fructosamine levels were also higher at 221±40µmol/L vs 192±22µmol/l (P<0.001), respectively, and remained significant even after adjusting for maternal age, BMI, parity, type of diabetes, antecedents of macrosomia and excessive gestational weight gain. By contrast, HbA1c did not differ between the two groups. In fact, nearly two-thirds (64.7%) of the mothers of macrosomic newborns had fructosamine levels>200µmol/l vs 31.9% of mothers with non-macrosomic newborns (P<0.05). CONCLUSION: High fructosamine levels are associated with macrosomia in the newborns of well-controlled hyperglycaemic pregnant women.

Skin autofluorescence predicts major adverse cardiovascular events in patients with type 1 diabetes: a 7-year follow-up study.

BACKGROUND: Advanced glycation end-products play a role in diabetic vascular complications. Their optical properties allow to estimate their accumulation in tissues by measuring the skin autofluorescence (SAF). We searched for an association between SAF and major adverse cardiovascular events (MACE) incidence in subjects with Type 1 Diabetes (T1D) during a 7 year follow-up. METHODS: During year 2009, 232 subjects with T1D were included. SAF measurement, clinical [age, sex, body mass index (BMI), comorbidities] and biological data (HbA1C, blood lipids, renal parameters) were recorded. MACE (myocardial infarction, stroke, lower extremity amputation or a revascularization procedure) were registered at visits in the center or by phone call to general practitioners until 2016. RESULTS: The participants were mainly men (59.5%), 51.5 ± 16.7 years old, with BMI 25.0 ± 4.1 kg/m2, diabetes duration 21.5 ± 13.6 years, HbA1C 7.6 ± 1.1%. LDL cholesterol was 1.04 ± 0.29 g/L, estimated Glomerular Filtration Rates (CKD-EPI): 86.3 ± 26.6 ml/min/1.73 m2. Among these subjects, 25.1% were smokers, 45.3% had arterial hypertension, 15.9% had elevated AER (≥ 30 mg/24 h), and 9.9% subjects had a history of previous MACE. From 2009 to 2016, 22 patients had at least one new MACE: 6 myocardial infarctions, 1 lower limb amputation, 15 revascularization procedures. Their SAF was 2.63 ± 0.73 arbitrary units (AU) vs 2.08 ± 0.54 for other patients (p = 0.002). Using Cox-model, after adjustment for age (as the scale time), sex, diabetes duration, BMI, hypertension, smoking status, albumin excretion rates, statin treatment and a previous history of MACE, higher baseline levels of SAF were significantly associated with an increased risk of MACE during follow-up (HR = 4.13 [1.30-13.07]; p = 0.02 for 1 AU of SAF) and Kaplan-Meier curve follow-up showed significantly more frequent MACE in group with SAF upper the median (p = 0.001). CONCLUSION: A high SAF predicts MACE in patients with T1D.

Skin autofluorescence and peripheral neuropathy four years later in type 1 diabetes.

OBJECTIVE: Advanced glycation end products (AGEs) are involved in diabetes complications. We aimed to investigate whether the accumulation of AGEs measured by skin autofluorescence (sAF) was associated with signs of diabetic peripheral neuropathy and to sensitivity, pain, motor and autonomic function 4 years later in patients with type 1 diabetes. METHODS: At baseline, 188 patients (age 51 years, diabetes duration 22 years) underwent skin autofluorescence measurement using the AGE Reader. Four years later, signs of diabetic peripheral neuropathy were defined as the presence of neuropathic pain and/or feet sensory loss or foot ulceration. Neurological tests were systematically performed: vibration perception threshold by neuroesthesiometry, neuropathic pain by the Douleur Neuropathique en 4 Questions score, muscle strength by dynamometry and electrochemical skin conductance. Multivariate analyses were adjusted by age, sex, height, body mass index, tobacco, HbA1c , diabetes duration, estimated glomerular filtration rate and albumin excretion rate. RESULTS: At the 4-year follow-up, 13.8% of patients had signs of diabetic peripheral neuropathy. The baseline sAF was higher in those with signs of diabetic peripheral neuropathy (2.5 ± 0.7 vs 2.1 ± 0.5 arbitrary units (AU), p < 0.0005). In the multivariate analysis, a 1 SD higher skin autofluorescence at baseline was associated with an increased risk of signs of neuropathy (OR = 2.68, p = 0.01). All of the neurological tests were significantly altered in the highest quartile of the baseline sAF (>2.4 AU) compared with the lowest quartiles after multivariate adjustment. CONCLUSION: This non-invasive measurement of skin autofluorescence may have a value for diabetic peripheral neuropathy in type 1 diabetes and a potential clinical utility for detection of diabetic peripheral neuropathy. Copyright © 2016 John Wiley & Sons, Ltd.

Is skin autofluorescence a marker of metabolic memory in pregnant women with diabetes?

AIM: To determine whether skin autofluorescence can help to detect those who have previously had abnormal glucose levels among women referred for diabetes during pregnancy. METHODS: Using an advanced glycation end product reader (AGE Reader(tm) (;) DiagnOptics BV, Groningen, the Netherlands), we measured forearm skin autofluorescence at 24-30 weeks of gestation in all women who were referred to our Nutrition Diabetology unit for diabetes during pregnancy. RESULTS: The study included 230 women (200 with gestational diabetes and 30 with pre-gestational diabetes, of whom 21 had Type 1 and nine had Type 2 diabetes) and a reference group of 22 normoglycaemic non-pregnant women. Skin autofluorescence was significantly higher in women with pre-gestational diabetes (1.97 ± 0.44 arbitary units) compared with gestational diabetes (1.77 ± 0.32 arbitary units; P = 0.003) and lower in the reference group (1.60 ± 0.32 arbitary units; P = 0.009 vs all pregnant women). Among women with gestational diabetes, 71 had a history of hyperglycaemia (i.e. gestational diabetes or macrosomia in a previous pregnancy or discovery of diabetes before 24th gestational week in the present pregnancy). These women had higher levels of skin autofluorescence (1.83 ± 0.35 arbitary units) than women with gestational diabetes without previous history of hyperglycaemia (1.73 ± 0.30 arbitary units; P = 0.04, non-significant, adjusted for age). Skin autofluorescence increased with the number of criteria present for previous hyperglycaemia (P for trend = 0.008) and was significantly associated with having two or three criteria for hyperglycaemia after adjusting for age (P = 0.02). CONCLUSIONS: Skin autofluorescence could reflect previous long-term hyperglycaemia in pregnant women, and could therefore be a marker of metabolic memory.

Association of advanced glycation end products and chronic kidney disease with macroangiopathy in type 2 diabetes.

AIMS: Accumulation of advanced glycation end-products (AGEs), may explain the major contribution of chronic kidney disease (CKD) to cardiovascular events in patients with type 2 diabetes (T2D) related to their impaired renal function. The aim of this study was to analyze the factors associated with AGE assessed by skin autofluorescence and their association with macroangiopathy in T2D. METHODS: We measured skin autofluorescence in patients hospitalized for T2D. Glomerular filtration rates were estimated (eGFR) by the EPI-CKD formula. Associations between skin autofluorescence, renal function and macroangiopathy were explored by multivariate analyses adjusting for diabetes duration and control. RESULTS: The 418 patients had T2D since 13.3 (SD 9.8) years on average, high mean HbA1C: 8.9%, (SD 1.8), (74 mmol/mol, (SD 15)) and often renal complications (49.4% with CKD). Their mean skin autofluorescence was 2.53 (SD 0.62) A.U. In multivariate linear regression, skin autofluorescence was significantly associated with age (+0.20 for ten more years, p<0.0001), renal insufficiency (-0.07 for less 10 mL/min/1.73 m² eGFR, p<0.0001) and smoking (+0.21, p=0.0004). Autofluorescence (p=0.01), but not CKD, was associated with macroangiopathy independent of diabetes duration and control. CONCLUSIONS: Accumulation of AGEs is independently associated with renal insufficiency and macroangiopathy in patients with T2D.

The influence of sex on renal function decline in people with Type 2 diabetes.

AIMS: Several reports have suggested a relationship between male sex and albuminuria in Type 2 diabetes, but impact on renal function decline has not been established. Our aim was to describe the influence of sex on renal function decline in Type 2 diabetes. METHODS: SURDIAGENE, an inception cohort, consisted in 1470 people with Type 2 diabetes. Patients without renal replacement therapy and with ≥ 3 serum creatinine determinations during follow-up prior to end-stage renal disease were included in the study. Estimated glomerular filtration rate was calculated using the Chronic Kidney Disease Epidemiology Collaboration equation. Primary outcome was steep estimated glomerular filtration rate (eGFR) decline, defined as a yearly slope value lower than -3.5 ml min(-1) 1.73 m(-2). Secondary outcomes were estimated glomerular filtration rate trajectories according to sex and occurrence of end-stage renal disease. RESULTS: A total of 22 914 serum creatinine determinations were considered in 1146 participants (60% men), aged 65 ± 11 years, with a median follow-up duration of 5.7 years (range 0.1-10.2). Median yearly estimated glomerular filtration rate slope was -1.31 ml min(-1) 1.73 m(-2) in women and -1.77 ml min(-1) 1.73 m(-2) in men (P < 0.001). Men were more likely than women to develop end-stage renal disease (22 men vs. 7 women; P(log-rank) = 0.03). Male sex was an independent risk factor of steep estimated glomerular filtration rate decline [adjusted odds ratio = 1.33 (1.02-1.76), P = 0.04] after adjustment for age, time from diagnosis of Type 2 diabetes, glycated haemoglobin, systolic blood pressure and urinary albumin:creatinine ratio. A multivariable linear mixed-effects model showed a significant difference of estimated glomerular filtration rate trajectories between men and women (P < 0.001). CONCLUSION: Male sex is an important independent factor associated with renal function decline in Type 2 diabetes.

Early changes in respiratory quotient and resting energy expenditure predict later weight changes in patients treated for poorly controlled type 2 diabetes.

AIM: This study looked at whether early changes in resting energy expenditure (REE) and respiratory quotient (RQ) are correlated with later weight changes in patients with type 2 diabetes (T2D) being treated with insulin or GLP-1 analogues, or diet. METHODS: A total of 67 patients (age: 57 ± 9 years; BMI: 33.7 ± 5.0 kg/m(2); HbA1c: 9.9 ± 1.5%) began taking an insulin analogue at bedtime (INS, n=28; initial dose: 0.2 IU/kg) or a GLP-1 analogue (GLP-1, n=23), or only a dietary intervention (diet, n=16; restricted carbohydrates and calories). Their respiratory exchanges were monitored on days 0, 1 and 2 before breakfast. RESULTS: Two days after starting the bedtime insulin analogue, fasting glycaemia improved (INS: -65 ± 41 mg/dL; GLP-1: -29 ± 48 mg/dL; diet: -31 ± 46 mg/dL; P<0.05), REE decreased (INS: -162 ± 241 kcal/24h; GLP-1: 0 ± 141 kcal/24h; diet: -41 ± 154 kcal/24h; P<0.05) and RQ increased (from 0.76 ± 0.04 to 0.80 ± 0.04; P<0.01), whereas only RQ decreased with diet (from 0.79 ± 0.05 to 0.76 ± 0.04; P<0.05) and remained unchanged with GLP-1 (P<0.005 for ΔRQ across treatments). Only 33 patients attended the scheduled examination three months later. HbA1c improved (INS, n=16: -1.7 ± 1.4%; GLP-1, n=12: -2.1 ± 1.4%; diet, n=5: -1.7 ± 2.8%; NS), while weight changes differed (INS: +1.5 ± 4.3 kg; GLP-1: -2.8 ± 2.8 kg; diet: -2.2 ± 2.7 kg; P<0.005). After three months, weight changes correlated with early changes in REE (r=-0.37, P<0.05) and RQ (r=+0.43, P<0.01), and remained correlated when both changes were included in a multivariate regression analysis (r=0.58, P<0.005). CONCLUSION: In poorly controlled patients with T2D and two days after the introduction of a bedtime insulin analogue, REE decreased by -9% while RQ increased by +5%, pointing to a reduction of lipid oxidation. These changes were predictive of later weight gain.

Skin autofluorescence is associated with past glycaemic control and complications in type 1 diabetes mellitus.

As skin autofluorescence (AF) can assess subcutaneous accumulation of fluorescent advanced glycation end-products (AGEs), this study aimed to investigate whether it was linked to glycaemic control and complications in patients with type 1 diabetes mellitus (T1DM). Using the AGE Reader™, AF was measured in T1DM patients referred to Haut-Levêque Hospital (Bordeaux, France); data on their HbA1c levels measured every 6months as far back as the last 5years were also collected. The association of AF with the patients' past glucose control, based on their latest HbA1c values, and the means of the last five and 10 HbA1c values, and with diabetic complications was also examined by linear regression analysis. The sample included 300 patients: 58% were male; the mean age was 49 (SD 17) years and the mean diabetes duration was 21 (SD 13) years. The median skin AF measurement was 2.0 [25th-75th percentiles: 1.7-2.4] arbitrary units (AU), and this was associated with age (ß=0.15 per 10years, P<0.001) and diabetes duration (ß=0.17 per 10years, P<0.001). After adjusting for age and estimated glomerular filtration rate (eGFR), the skin AF measurement was also related to the means of the last five and 10 HbA1c values (ß=0.10 per 1% of HbA1c, P=0.005, and ß=0.13 per 1% of HbA1c, P=0.001, respectively). In addition, the skin AF was associated with retinopathy (P<0.001), albuminuria (P<0.001) and decreased eGFR (P<0.001). In conclusion, the skin AF is related to the long-term glucose control and diabetic complications.