Machine Learning Decision Support for Detecting Lipohypertrophy With Bedside Ultrasound: Proof-of-Concept Study.

BACKGROUND: The most common dermatological complication of insulin therapy is lipohypertrophy. OBJECTIVE: As a proof of concept, we built and tested an automated model using a convolutional neural network (CNN) to detect the presence of lipohypertrophy in ultrasound images. METHODS: Ultrasound images were obtained in a blinded fashion using a portable GE LOGIQ e machine with an L8-18I-D probe (5-18 MHz; GE Healthcare). The data were split into train, validation, and test splits of 70%, 15%, and 15%, respectively. Given the small size of the data set, image augmentation techniques were used to expand the size of the training set and improve the model's generalizability. To compare the performance of the different architectures, the team considered the accuracy and recall of the models when tested on our test set. RESULTS: The DenseNet CNN architecture was found to have the highest accuracy (76%) and recall (76%) in detecting lipohypertrophy in ultrasound images compared to other CNN architectures. Additional work showed that the YOLOv5m object detection model could be used to help detect the approximate location of lipohypertrophy in ultrasound images identified as containing lipohypertrophy by the DenseNet CNN. CONCLUSIONS: We were able to demonstrate the ability of machine learning approaches to automate the process of detecting and locating lipohypertrophy.

Combining GLP-1 Receptor Agonists and Basal Insulin in Older Adults with Type 2 Diabetes: Focus on Lixisenatide and Insulin Glargine.

Estimates suggest that there are currently 122.8 million adults 65-99 years of age living with diabetes, of whom 90-95% are diagnosed with type 2 diabetes (T2D). Over the past two decades, a greater understanding of the complex and multifactorial pathogenesis of T2D has resulted in the development and introduction of new-generation classes of glucose-lowering therapies, which are now extensively endorsed by prevailing guidelines and are increasingly being used worldwide. These newer agents may further assist in the effective pharmacological management of T2D through the provision of patient-centered care that acknowledges multimorbidity and is respectful of and responsive to individual patient preferences and barriers. Given these considerations, the therapeutic approach in older patients with T2D is complex, particularly in those who have functional dependence, frailty, dementia, or who are at end-of-life. It is currently too early to draw conclusions on the long-term use of newer glucose-lowering agents in this population, as their efficacy and safety in older adults remains largely unknown. In this review, we will discuss considerations for the use of glucose-lowering treatments in older adults, with particular focus on the use of basal insulin and glucagon-like peptide-1 receptor agonists, and the rationale for the use of combination therapy comprising these agents. Finally, we will review clinical data from studies of the fixed-ratio combination of insulin glargine and lixisenatide in older patients with T2D. FUNDING: Sanofi US, Inc.

Efficacy and safety of lixisenatide as add-on therapy to basal insulin in older adults with type 2 diabetes in the GetGoal-O Study.

BACKGROUND: This study compared the efficacy and safety of lixisenatide with placebo as add-on therapy to basal insulin (BI) in adults aged ≥70 years with type 2 diabetes (T2D), with or without moderate renal insufficiency. METHODS: This post hoc analysis evaluated data from non-frail patients with T2D inadequately controlled on BI with or without oral antidiabetic drugs (n = 108), randomized to once-daily lixisenatide 20 µg or placebo for 24 weeks (GetGoal-O Study). The primary endpoint was the change in HbA1c from baseline to Week 24. Secondary endpoints included changes from baseline in fasting plasma glucose, 2-hour postprandial plasma glucose (PPG), average seven-point self-monitored plasma glucose (SMPG), area under the curve for SMPG, daily BI dose, body weight, proportion of patients achieving HbA1c > 0.5%, and composite endpoints. Safety outcomes included the incidence of documented symptomatic hypoglycemia (plasma glucose <60 mg/dL) and gastrointestinal treatment-emergent adverse events (TEAEs). Outcomes were also analyzed by the occurrence of moderate renal insufficiency. RESULTS: Compared with placebo, lixisenatide-treated patients had significantly greater reductions in HbA1c, 2-hour PPG, average seven-point SMPG, and body weight. Documented symptomatic hypoglycemia was approximately two-fold higher in patients treated with placebo than lixisenatide (12.7% vs 5.7%). GI TEAEs occurred more frequently in the lixisenatide- than placebo-treated group (34% vs 9.1%). Moderate renal insufficiency (estimated glomerular filtration rate between ≥30 and <60 mL/min/1.73 m2 ) did not negatively affect lixisenatide efficacy or safety. A greater proportion of patients treated with lixisenatide than placebo achieved composite endpoints. CONCLUSIONS: Add-on therapy with lixisenatide in non-frail patients aged ≥70 years with T2D uncontrolled with BI is effective, safe, and well tolerated and should be considered in this population.

The Super-Seniors Study: Phenotypic characterization of a healthy 85+ population.

BACKGROUND: To understand why some people live to advanced age in good health and others do not, it is important to study not only disease, but also long-term good health. The Super-Seniors Study aims to identify factors associated with healthy aging. METHODS: 480 healthy oldest-old 'Super-Seniors' aged 85 to 105 years and never diagnosed with cancer, cardiovascular disease, diabetes, dementia, or major pulmonary disease, were compared to 545 mid-life controls aged 41-54, who represent a group that is unselected for survival from late-life diseases. Health and lifestyle information, personal and family medical history, and blood samples were collected from all participants. Super-Seniors also underwent four geriatric tests. RESULTS: Super-Seniors showed high cognitive (Mini-Mental State Exam mean = 28.3) and functional capacity (Instrumental Activities of Daily Living Scale mean = 21.4), as well as high physical function (Timed Up and Go mean = 12.3 seconds) and low levels of depression (Geriatric Depression Scale mean = 1.5). Super-Seniors were less likely to be current smokers than controls, but the frequency of drinking alcohol was the same in both groups. Super-Seniors were more likely to have 4 or more offspring; controls were more likely to have no children. Female Super-Seniors had a mean age of last fertility 1.9 years older than controls, and were 2.3 times more likely to have had a child at ≥ 40 years. The parents of Super-Seniors had mean ages of deaths of 79.3 years for mothers, and 74.5 years for fathers, each exceeding the life expectancy for their era by a decade. CONCLUSIONS: Super-Seniors are cognitively and physically high functioning individuals who have evaded major age-related chronic diseases into old age, representing the approximately top 1% for healthspan. The familiality of long lifespan of the parents of Super-Seniors supports the hypothesis that heritable factors contribute to this desirable phenotype.

Measurement of Pro-Islet Amyloid Polypeptide (1-48) in Diabetes and Islet Transplants.

Context: Islet amyloid is a feature of ß-cell failure in type 2 diabetes (T2D) and type 1 diabetes (T1D) recipients of islet transplants. Islet amyloid contains islet amyloid polypeptide (IAPP; amylin), a circulating peptide that is produced in ß cells by processing of its precursor, proIAPP1-67, via an intermediate form, proIAPP1-48. Elevated proinsulin to C-peptide ratios in the plasma of persons with diabetes suggest defects in ß-cell prohormone processing. Objective: Determine whether plasma levels of precursor forms of IAPP are elevated in diabetes. Design, Setting, and Patients: We developed an immunoassay to detect proIAPP1-48 in human plasma, and we determined the ratio of proIAPP1-48 to mature IAPP in subjects with T1D, T2D, recipients of islet transplants, and healthy controls. Results: The proIAPP1-48 immunoassay had a limit of detection of 0.18 ± 0.06 pM and cross-reactivity with intact proIAPP1-67 <15%. Healthy individuals had plasma concentrations of proIAPP1-48 immunoreactivity of 1.5 ± 0.2 pM and a proIAPP1-48 to total IAPP ratio of 0.28 ± 0.03. Plasma concentrations of proIAPP1-48 immunoreactivity were not significantly different in subjects with T2D but were markedly increased in T1D recipients of islet transplants. Children and adults with T1D had reduced mature IAPP levels relative to age-matched controls but an elevated ratio of proIAPP1-48 to total IAPP. Conclusion: The ß cells in T1D and islet transplants have impaired processing of the proIAPP1-48 intermediate. The ratio of proIAPP1-48-to-IAPP immunoreactivity may have value as a biomarker of ß-cell stress and dysfunction.

Lixisenatide Therapy in Older Patients With Type 2 Diabetes Inadequately Controlled on Their Current Antidiabetic Treatment: The GetGoal-O Randomized Trial.

OBJECTIVE: To evaluate the efficacy and safety of lixisenatide versus placebo on glycemic control in older patients with type 2 diabetes uncontrolled on their current antidiabetic treatment. RESEARCH DESIGN AND METHODS: In this phase III, double-blind, randomized, placebo-controlled, two-arm, parallel-group, multicenter trial, patients aged ≥70 years were randomized to receive once-daily lixisenatide 20 µg or placebo before breakfast concomitantly with their existing antidiabetic therapy (including insulin) for 24 weeks. Patients at risk for malnutrition or with moderate to severe cognitive impairment were excluded. The primary end point was absolute change in HbA1c from baseline to week 24. Secondary end points included change from baseline to week 24 in 2-h postprandial plasma glucose (PPG) and body weight. RESULTS: A total of 350 patients were randomized. HbA1c decreased substantially with lixisenatide (-0.57% [6.2 mmol/mol]) compared with placebo (+0.06% [0.7 mmol/mol]) from baseline to week 24 (P < 0.0001). Mean reduction in 2-h PPG was significantly greater with lixisenatide (-5.12 mmol/L) than with placebo (-0.07 mmol/L; P < 0.0001). A greater decrease in body weight was observed with lixisenatide (-1.47 kg) versus placebo (-0.16 kg; P < 0.0001). The safety profile of lixisenatide in this older population, including rates of nausea and vomiting, was consistent with that observed in other lixisenatide studies. Hypoglycemia was reported in 17.6% of patients with lixisenatide versus 10.3% with placebo. CONCLUSIONS: In nonfrail older patients uncontrolled on their current antidiabetic treatment, lixisenatide was superior to placebo in HbA1c reduction and in targeting postprandial hyperglycemia, with no unexpected safety findings.

Does GLP-1 suppress its own basal secretion?

PURPOSE/AIM: Negative feedback controls in endocrine regulatory systems are well recognized. The incretins and their role in glucose regulation have been of major interest recently. Whether the same negative control system applies to the regulation of incretin secretion is not clear. We sought to examine the hypothesis that exogenous administration of glucagon like peptide-1, GLP-1(7-36) amide or its metabolite GLP-1(9-36) amide, reduces the endogenous basal release of this incretin. MATERIALS AND METHODS: We evaluated the endogenous basal release of GLP-1 using two separate study designs. In protocol A we examined the GLP-1(7-36) amide levels during the infusion of GLP-1(9-36) amide. In protocol B, we used PYY and GLP-2 as biomarkers for the endogenous basal release of GLP-1(7-36) amide and assessed the endogenous basal release of these two hormones during the GLP-1(7-36) infusion. Twelve lean and 12 obese subjects were enrolled in protocol A and 10 obese volunteers in protocol B. RESULTS: The plasma levels of GLP-1(7-36) amide in protocol A and PYY and GLP-2 in protocol B remained unchanged during the exogenous infusion of GLP-1(9-36) and GLP-1(7-36) amide, respectively. CONCLUSIONS: The negative feedback control system as described by inhibition of the release of endogenous hormone while infusing it exogenously was not observed for the basal secretion of GLP-1(7-36) amide.

Aerobic training in older adults with type 2 diabetes and vasodepressive carotid sinus hypersensitivity.

BACKGROUND AND AIMS: Vasodepressive carotid sinus hypersensitivity (V-CSH) is a common but incurable etiology for fainting in older adults with diabetes (OADM), and is diagnosed by carotid sinus massage (CSM). Aerobic exercise has been shown to be an effective therapy for other neuroautonomic etiologies of syncope (such as orthostatic hypotension), but the effectiveness of aerobic training in V-CSH remains unknown. We examined whether aerobic training could attenuate the vasodepressive response to CSM in OADM (older adults with type 2 diabetes) subjects complicated by V-CSH. METHODS: Forty OADM subjects (mean age 72.2 ± 0.7) complicated by V-CSH were recruited. Subjects were randomized to each of two groups: an aerobic group (AT, n = 20, 3 months vigorous aerobic exercise), and a nonaerobic (NA, n = 20, no aerobic exercise) group. Exercise sessions were supervised by a certified exercise trainer three times per week. The vasodepressive response [defined as the decrease in systolic blood pressure (SBP) during CSM] was measured before and after the training intervention using a Finometer. RESULTS: The intervention had no impact on the number of subjects that met the criteria for V-CSM in either the AT or NA groups, regardless of the criteria used (-10, -20, -30, -40 and -50 mmHg). There was no training effect on the vasodepressive response in either the AT or NA group (P = 0.214, 2-way analysis of variance, -30 mmHg definition for V-CSH). CONCLUSIONS: Aerobic training has no effect on the SBP response to CSM in OADM subjects with V-CSH. Unlike in other neuroautonomic etiologies for fainting, aerobic exercise is not effective as a treatment for V-CSH, at least in the OADM population.

Genetic variation in healthy oldest-old.

Individuals who live to 85 and beyond without developing major age-related diseases may achieve this, in part, by lacking disease susceptibility factors, or by possessing resistance factors that enhance their ability to avoid disease and prolong lifespan. Healthy aging is a complex phenotype likely to be affected by both genetic and environmental factors. We sequenced 24 candidate healthy aging genes in DNA samples from 47 healthy individuals aged eighty-five years or older (the 'oldest-old'), to characterize genetic variation that is present in this exceptional group. These healthy seniors were never diagnosed with cancer, cardiovascular disease, pulmonary disease, diabetes, or Alzheimer disease. We re-sequenced all exons, intron-exon boundaries and selected conserved non-coding sequences of candidate genes involved in aging-related processes, including dietary restriction (PPARG, PPARGC1A, SIRT1, SIRT3, UCP2, UCP3), metabolism (IGF1R, APOB, SCD), autophagy (BECN1, FRAP1), stem cell activation (NOTCH1, DLL1), tumor suppression (TP53, CDKN2A, ING1), DNA methylation (TRDMT1, DNMT3A, DNMT3B) Progeria syndromes (LMNA, ZMPSTE24, KL) and stress response (CRYAB, HSPB2). We detected 935 variants, including 848 single nucleotide polymorphisms (SNPs) and 87 insertion or deletions; 41% (385) were not recorded in dbSNP. This study is the first to present a comprehensive analysis of genetic variation in aging-related candidate genes in healthy oldest-old. These variants and especially our novel polymorphisms are valuable resources to test for genetic association in models of disease susceptibility or resistance. In addition, we propose an innovative tagSNP selection strategy that combines variants identified through gene re-sequencing- and HapMap-derived SNPs.

Reduced progression of diabetic retinopathy after islet cell transplantation compared with intensive medical therapy.

BACKGROUND: Diabetic retinopathy is a major complication of type 1 diabetes and remains a leading cause of visual loss. There have been no comparisons of the effectiveness of intensive medical therapy and islet cell transplantation on preventing progression of diabetic retinopathy. METHODS: The British Columbia islet transplant program is conducting a prospective, crossover study comparing medical therapy and islet cell transplantation on the progression of diabetic retinopathy. Progression was defined as the need for laser treatment or a one step worsening along the international disease severity scale. An interim data analysis was performed after a mean 36-month follow-up postislet transplantation and these results are presented. RESULTS: The medical and postislet transplant groups were similar at baseline. Subjects after islet transplantation had better glucose control than the medically treated subjects (mean HbA1c 6.7%+/-0.9% vs. 7.5+/-1.2, P<0.01) and were C-peptide positive. Progression occurred significantly more often in all subjects in the medical group (10/82 eyes, 12.2%) than after islet transplantation (0/51 eyes, 0%) (P<0.01). Considering only subjects who have received transplants, progression occurred in 6/51 eyes while on medical treatment and 0/51 posttransplant (P<0.02). CONCLUSIONS: Progression of diabetic retinopathy was more likely to occur during medical therapy than after islet cell transplantation.

GLP-1 (9-36) amide, cleavage product of GLP-1 (7-36) amide, is a glucoregulatory peptide.

OBJECTIVE: Glucagon-like peptide-1 (GLP-1) (7-36) amide is a glucoregulatory hormone with insulinotropic and insulinomimetic actions. We determined whether the insulinomimetic effects of GLP-1 are mediated through its principal metabolite, GLP-1 (9-36) amide (GLP-1m). METHODS AND PROCEDURES: Glucose turnover during two, 2-h, euglycemic clamps was measured in 12 lean and 12 obese (BMI <25 or >30 kg/m(2)) male and female subject volunteers with normal oral glucose tolerance test. Saline or GLP-1m were infused from 0 to 60 min in each study. Additionally, seven lean and six obese subjects underwent a third clamp in which the GLP-1 receptor (GLP-1R) antagonist, exendin (9-39) amide was infused from -60 to 60 min with GLP-1m from 0 to 60 min. RESULTS: No glucose infusion was required in lean subjects to sustain euglycemia (glucose clamp) during saline or GLP-1m infusions. However, in obese subjects glucose infusion was necessary during GLP-1m infusion alone in order to compensate for a marked (>50%) inhibition of hepatic glucose production (HGP). Plasma insulin levels remained constant in lean subjects but rose significantly in obese subjects after termination of the peptide infusions. During GLP-1R blockade, infusion of glucose was immediately required upon starting GLP-1m infusions in all subjects due to a more dramatic reduction in HGP, as well as a delayed and modest insulinotropic response. DISCUSSION: We conclude that GLP-1m potently inhibits HGP and is a weak insulinotropic agent. These properties are particularly apparent and pronounced in obese but only become apparent in lean subjects during GLP-1 (7-36) receptor blockade. These previously unrecognized antidiabetogenic actions of GLP-1m may have therapeutic usefulness.

Effect of exenatide on beta cell function after islet transplantation in type 1 diabetes.

BACKGROUND: Islet transplantation can reduce or eliminate the need for insulin in patients with type 1 diabetes. Exenatide is a long acting analogue of Glucagon-like peptide-1 (GLP-1) that augments glucose induced insulin secretion, and may increase beta cell mass. We evaluated the effect of exenatide on insulin secretion after islet transplantation. METHODS: Eleven C-peptide positive islet cell recipients with elevated glucose levels were treated with exenatide for three months. Response was assessed by insulin requirements, meal tolerance tests, and hyperglycemic glucose clamps. RESULTS: Ten patients responded to exenatide. Two patients who had not restarted insulin achieved good glycemic control and one patient who had received 5500 IE/kg in first islet infusion was able to stop insulin. Seven other patients decreased their insulin dose by 39% on exenatide. Hyperglycemic clamp studies showed a rise in second phase insulin release (before exenatide: 246+/-88 pM; during exenatide: 644+/-294 pM, P<0.01). Meal tolerance studies before and one month after stopping exenatide did not show a difference in glucose or C-peptide values. Nausea and vomiting were the major side effects. CONCLUSIONS: Exenatide stimulates insulin secretion in islet transplant recipients. It reduces insulin dose in some patients and may delay the need to resume insulin in others. We did not find any evidence of a trophic effect on islets.

Regulation of appetite in lean and obese adolescents after exercise: role of acylated and desacyl ghrelin.

CONTEXT: Increased physical activity is an integral part of weight loss programs in adolescents. We hypothesized that exercise could affect appetite-regulating hormones and the subjective desire to eat, which could partly explain the poor success rate of the existing interventions. OBJECTIVE: The objective of this study was to investigate prospectively the effects of exercise on acylated ghrelin (AG) and desacyl ghrelin (DG) concentrations and on appetite. SETTING: The setting for this study was a tertiary care center. PARTICIPANTS: Normal-weight [NW; body mass index (mean +/- se), 20.7 +/- 0.5 kg/m2] and overweight (OW; body mass index, 32.4 +/- 1.7) male adolescents (n = 17/group, age 15.3 +/- 0.2 yr) were studied. INTERVENTION: Those studied participated in 5 consecutive days of aerobic exercise (1 h/d). MAIN OUTCOME: Changes in AG and DG concentrations and in appetite during a test meal were studied. RESULTS: Exercise did not significantly affect insulin sensitivity or body weight. Fasting total (AG and DG) ghrelin concentrations were lower in OW (600 +/- 33 pg/ml) compared with NW (764 +/- 33 pg/ml, P < 0.05) boys and were not affected by exercise. In contrast, there was a differential effect of exercise on both AG and DG (P

Effect of glucagon-like peptide-1 (7-37) on beta-cell function after islet transplantation in type 1 diabetes.

Islet transplantation can improve glycemic control in patients with type 1 diabetes and reduce or eliminate the need for insulin. Glucagon-like peptide-1 (GLP-1) is an intestinal insulinotropic hormone that augments glucose induced insulin secretion, and has a trophic effect on beta-cells. We evaluated the effect of GLP-1 on insulin secretion after islet transplantation. Patients underwent hyperglycemic glucose clamp studies 1 month after their last transplant. GLP-1 was infused during the second hour of the hyperglycemic clamp. Results were compared to normal control subjects and patients with type 2 diabetes who underwent an identical hyperglycemic clamp. First phase insulin release was absent in patients, while second phase insulin was not significantly reduced (control: 118+/-29 pM; type 2 diabetes: 68+/-20 pM; transplant: 99+/-18 pM, p=ns for all). GLP-1 had a significant incretin effect on transplanted islets but the response was less than controls (control: 2108+/-344 pM; type 2 diabetes: 929+/-331 pM; transplant: 329+/-112 pM, p<0.0001 control versus transplant). Islet transplant patients had no evidence of resistance to insulin mediated glucose disposal. We conclude that transplanted islets retain the ability to respond to GLP-1.

Effect of glucagon-like peptide 1 (7-36 amide) on insulin-mediated glucose uptake in patients with type 1 diabetes.

OBJECTIVE: To examine the insulinomimetic insulin-independent effects of glucagon-like peptide (GLP)-1 on glucose uptake in type 1 diabetic patients. RESEARCH DESIGN AND METHODS: We used the hyperinsulinemic-euglycemic clamp (480 pmol. m(-2) x min(-1)) in paired randomized studies of six women and five men with type 1 diabetes. In the course of one of the paired studies, the subjects also received GLP-1 at a dose of 1.5 pmol. kg(-1) x min(-1). The patients were 41 +/- 3 years old with a BMI of 25 +/- 1 kg/m(2). The mean duration of diabetes was 23 +/- 3 years. RESULTS: Plasma glucose was allowed to fall from a fasting level of approximately 11 mmol/l to 5.3 mmol/l in each study and thereafter was held stable at that level. Plasma insulin levels during both studies were approximately 900 pmol/l. Plasma C-peptide levels did not change during the studies. In the GLP-1 study, plasma total GLP-1 levels were elevated from the fasting level of 31 +/- 3 to 150 +/- 17 pmol/l. Plasma glucagon levels fell from the fasting levels of approximately 14 pmol/l to 9 pmol/l during both paired studies. Hepatic glucose production was suppressed during the glucose clamps in all studies. Glucose uptake was not different between the two studies ( approximately 40 micromol. kg(-1) x min(-1)). CONCLUSIONS: GLP-1 does not augment insulin-mediated glucose uptake in lean type 1 diabetic patients.

Effects of 1-mo bolus subcutaneous administration of exendin-4 in type 2 diabetes.

A gut insulinotropic peptide, glucagon-like peptide-1 (GLP-1), when given continuously subcutaneously, has been shown to be an effective agent to treat type 2 diabetes. Because of inactivation by dipeptidyl peptidase IV (DPP IV), it has a very short half-life (90-120 s), hence the need for continuous administration. Exendin-4 is an agonist of the GLP-1 receptor. It is not a substrate for DPP IV, and we previously demonstrated that intravenous administration has potent insulinotropic properties in type 2 diabetic volunteers. We evaluated the efficacy of bolus subcutaneous exendin-4 in insulin-naive type 2 diabetic volunteers. Ten patients aged 44-72 yr with mean fasting glucose levels of 11.4 +/- 0.9 mmol/l were enrolled, and daily or twice-daily bolus subcutaneous exendin-4 was self-administered for 1 mo. Glycosylated hemoglobin, multiple daily capillary blood glucose, beta-cell sensitivity to glucose, and peripheral tissue sensitivity to insulin were compared before and after treatment. The greatest decline in capillary blood glucose was seen before bed, with a drop from 15.5 to 9.2 mmol/l (P < 0.0001). Glycosylated hemoglobin improved significantly with treatment, from 9.1 to 8.3% (P = 0.009). beta-Cell sensitivity to glucose was improved, as assessed by C-peptide levels during a hyperglycemic clamp. No significant adverse effects were noted or reported. Our data suggest that, even with this short duration of therapy, exendin-4 treatment had a significant effect on glucose homeostasis.

Glucose tolerance, glucose utilization and insulin secretion in ageing.

Ageing is associated with an increased incidence of hypertension, macrovascular disease and type 2 diabetes (non-insulin-dependent diabetes). It has been suggested that a common mechanism may be responsible for all of these pathological states since all of these conditions often cluster in the same individual. Epidemiological and clinical data have consistently demonstrated an association between insulin resistance and/or hyperinsulinaemia and glucose intolerance, dyslipidaemia and elevated systolic blood pressures. Therefore, insulin resistance and hyperinsulinaemia have been proposed as the causal link among the elements of the clusters. The elderly are more glucose intolerant and insulin resistant, but it remains controversial whether this decrease in function is due to an inevitable consequence of 'biological ageing' or due to environmental or lifestyle variables, noticeably increased adiposity/altered fat distribution and physical inactivity. An increase of these modifiable factors has been shown to result in increases in insulin resistance and hyperinsulinaemia and vice versa. However, insulin secretion appears to decrease with age even after adjustments for differences in adiposity, fat distribution and physical activity. The glucose intolerance of ageing may be due, in part, to decreased insulin sensitivity of pancreatic / cells to insulinotropic gut hormones (GLP1/GIP) and in part to alterations of hepatic glucose production.