RESUMO
The kidney plays an important role in glucose homeostasis via gluconeogenesis, glucose utilization, and glucose reabsorption from the renal glomerular filtrate. After an overnight fast, 20-25% of glucose released into the circulation originates from the kidneys through gluconeogenesis. In this post-absorptive state, the kidneys utilize about 10% of all glucose utilized by the body. After glucose ingestion, renal gluconeogenesis increases and accounts for approximately 60% of endogenous glucose release in the postprandial period. Each day, the kidneys filter approximately 180g of glucose and virtually all of this is reabsorbed into the circulation. Hormones (most importantly insulin and catecholamines), substrates, enzymes, and glucose transporters are some of the various factors influencing the kidney's role. Patients with type 2 diabetes have an increased renal glucose uptake and release in the fasting and the post-prandial states. Additionally, glucosuria in these patients does not occur at plasma glucose levels that would normally produce glucosuria in healthy individuals. The major abnormality of renal glucose metabolism in type 1 diabetes appears to be impaired renal glucose release during hypoglycemia.
Assuntos
Diabetes Mellitus Tipo 2/metabolismo , Gluconeogênese/fisiologia , Glucose/metabolismo , Glicólise/fisiologia , Rim/metabolismo , Transportador 2 de Glucose-Sódio/metabolismo , Homeostase , HumanosRESUMO
This article summarizes our current knowledge of the epidemiology, pathogenesis, and morbidity of hypoglycemia in patients with diabetic kidney disease and reviews therapeutic limitations in this situation.
RESUMO
Hypoglycemia is a major problem associated with substantial morbidity and mortality in patients with diabetes and is often a major barrier to achieving optimal glycemic control. Chronic kidney disease not only is an independent risk factor for hypoglycemia but also augments the risk of hypoglycemia that is already present in people with diabetes. This article summarizes our current knowledge of the epidemiology, pathogenesis, and morbidity of hypoglycemia in patients with diabetes and chronic kidney disease and reviews therapeutic considerations in this situation. PubMed and MEDLINE were searched for literature published in English from January 1989 to May 2014 for diabetes mellitus, hypoglycemia, chronic kidney disease, and chronic renal insufficiency.
Assuntos
Diabetes Mellitus Tipo 1/complicações , Diabetes Mellitus Tipo 2/complicações , Hipoglicemia/induzido quimicamente , Hipoglicemiantes/efeitos adversos , Insuficiência Renal Crônica/complicações , Albuminúria/etiologia , Biomarcadores/urina , Bases de Dados Bibliográficas , Diabetes Mellitus Tipo 1/tratamento farmacológico , Diabetes Mellitus Tipo 1/epidemiologia , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/epidemiologia , Taxa de Filtração Glomerular/fisiologia , Humanos , Hipoglicemia/epidemiologia , Hipoglicemia/etiologia , Hipoglicemia/terapia , Hipoglicemiantes/uso terapêutico , Insulina/efeitos adversos , Insulina/uso terapêutico , Insuficiência Renal Crônica/tratamento farmacológico , Insuficiência Renal Crônica/epidemiologia , Fatores de RiscoRESUMO
The kidney plays an important role in glucose homeostasis via its production, utilization, and, most importantly, reabsorption of glucose from glomerular filtrate which is largely mediated via the sodium glucose co-transporter 2 (SGLT2). Pharmacological inhibition of SGLT2 increases urinary glucose excretion and decreases plasma glucose levels in an insulin-independent manner. Agents that inhibit SGLT2 represent a novel class of drugs, which has recently become available for treatment of type 2 diabetes. This article summarizes the rationale for use of these agents and reviews available clinical data on their efficacy, safety, and risks/benefits.
Assuntos
Diabetes Mellitus Tipo 2/tratamento farmacológico , Hipoglicemiantes/uso terapêutico , Inibidores do Transportador 2 de Sódio-Glicose , Humanos , Transportador 2 de Glucose-SódioRESUMO
Hypoglycemia remains a common problem for patients with diabetes and is associated with substantial morbidity and mortality. This article summarizes our current knowledge of the epidemiology, pathogenesis, risk factors, and complications of hypoglycemia in patients with diabetes and discusses prevention and treatment strategies.
Assuntos
Hipoglicemia/etiologia , Hipoglicemia/cirurgia , Hipoglicemia/terapia , Glicemia/metabolismo , Complicações do Diabetes/epidemiologia , Complicações do Diabetes/etiologia , Complicações do Diabetes/terapia , Diabetes Mellitus Tipo 1/complicações , Diabetes Mellitus Tipo 2/complicações , Humanos , Hipoglicemia/complicações , Hipoglicemia/epidemiologia , Transplante de Pâncreas , Fatores de RiscoRESUMO
OBJECTIVE: To compare efficacy and safety of lixisenatide once daily versus exenatide twice daily in type 2 diabetes inadequately controlled with metformin. RESEARCH DESIGN AND METHODS: Adults with diabetes inadequately controlled (HbA1c 7-10%) with metformin were randomized to lixisenatide 20 µg once daily (n=318) or exenatide 10 µg twice daily (n=316) in a 24-week (main period), open-label, parallel-group, multicenter study. The primary objective was a noninferiority assessment of lixisenatide versus exenatide in HbA1c change from baseline to week 24. RESULTS: Lixisenatide once daily demonstrated noninferiority in HbA1c reduction versus exenatide twice daily. The least squares mean change was -0.79% (mean decrease 7.97 to 7.17%) for lixisenatide versus -0.96% (mean decrease 7.96 to 7.01%) for exenatide, and treatment difference was 0.17% (95% CI, 0.033-0.297), meeting a predefined noninferiority upper CI margin of 0.4%. Responder rate (HbA1c<7.0%) and improvements in fasting plasma glucose were comparable. Both agents induced weight loss (from 94.5 to 91.7 kg and from 96.7 to 92.9 kg with lixisenatide and exenatide, respectively). Incidence of adverse events (AEs) was similar for lixisenatide and exenatide, as was incidence of serious AEs (2.8 and 2.2%, respectively). Discontinuations attributable to AEs occurred in 33 lixisenatide (10.4%) and 41 exenatide (13.0%) patients. In the lixisenatide group, fewer participants experienced symptomatic hypoglycemia (2.5 vs. 7.9%; P<0.05), with fewer gastrointestinal events (especially nausea; 24.5 vs. 35.1%; P<0.05). CONCLUSIONS: Add-on lixisenatide once daily in type 2 diabetes inadequately controlled with metformin demonstrated noninferior improvements in HbA1c, with slightly lower mean weight loss, lower incidence of hypoglycemia, and better gastrointestinal tolerability compared with exenatide twice daily.
Assuntos
Diabetes Mellitus Tipo 2/tratamento farmacológico , Hipoglicemiantes/administração & dosagem , Hipoglicemiantes/uso terapêutico , Metformina/administração & dosagem , Metformina/uso terapêutico , Peptídeos/administração & dosagem , Peptídeos/uso terapêutico , Adulto , Idoso , Idoso de 80 Anos ou mais , Esquema de Medicação , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento , Adulto JovemRESUMO
OBJECTIVE: To assess efficacy and safety of lixisenatide monotherapy in type 2 diabetes. RESEARCH DESIGN AND METHODS: Randomized, double-blind, 12-week study of 361 patients not on glucose-lowering therapy (HbA(1c) 7-10%) allocated to one of four once-daily subcutaneous dose increase regimens: lixisenatide 2-step (10 µg for 1 week, 15 µg for 1 week, and then 20 µg; n = 120), lixisenatide 1-step (10 µg for 2 weeks and then 20 µg; n = 119), placebo 2-step (n = 61), or placebo 1-step (n = 61) (placebo groups were combined for analyses). Primary end point was HbA(1c) change from baseline to week 12. RESULTS: Once-daily lixisenatide significantly improved HbA(1c) (mean baseline 8.0%) in both groups (least squares mean change vs. placebo: -0.54% for 2-step, -0.66% for 1-step; P < 0.0001). Significantly more lixisenatide patients achieved HbA(1c) <7.0% (52.2% 2-step, 46.5% 1-step) and ≤ 6.5% (31.9% 2-step, 25.4% 1-step) versus placebo (26.8% and 12.5%, respectively; P < 0.01). Lixisenatide led to marked significant improvements of 2-h postprandial glucose levels and blood glucose excursions measured during a standardized breakfast test. A significant decrease in fasting plasma glucose was observed in both lixisenatide groups versus placebo. Mean decreases in body weight (â¼2 kg) were observed in all groups. The most common adverse events were gastrointestinal-nausea was the most frequent (lixisenatide 23% overall, placebo 4.1%). Symptomatic hypoglycemia occurred in 1.7% of lixisenatide and 1.6% of placebo patients, with no severe episodes. Safety/tolerability was similar for the two dose regimens. CONCLUSIONS: Once-daily lixisenatide monotherapy significantly improved glycemic control with a pronounced postprandial effect (75% reduction in glucose excursion) and was safe and well tolerated in type 2 diabetes.
Assuntos
Diabetes Mellitus Tipo 2/sangue , Hipoglicemia/sangue , Hipoglicemiantes/administração & dosagem , Peptídeos/administração & dosagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Glicemia/metabolismo , Automonitorização da Glicemia , Pressão Sanguínea , Índice de Massa Corporal , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/epidemiologia , Relação Dose-Resposta a Droga , Método Duplo-Cego , Feminino , Hemoglobinas Glicadas/metabolismo , Humanos , Hipoglicemia/tratamento farmacológico , Hipoglicemia/epidemiologia , Hipoglicemiantes/efeitos adversos , Masculino , Pessoa de Meia-Idade , Náusea/induzido quimicamente , Peptídeos/efeitos adversos , Período Pós-Prandial , Resultado do Tratamento , Estados Unidos/epidemiologia , Adulto JovemRESUMO
Dapagliflozin is a highly selective sodium-glucose co-transporter 2 inhibitor developed for the treatment of Type 2 diabetes mellitus. Its inhibition of sodium-glucose co-transporter 2 blocks glucose reabsorption in the proximal tubule of the kidney, increasing renal glucose excretion via the urine, resulting in reduction of glycated hemoglobin, fasting plasma glucose and postprandial plasma glucose in patients with Type 2 diabetes mellitus. The pharmacokinetics and pharmacodynamics of dapagliflozin are suitable for once-daily dosing. Dapagliflozin improves glycemic control when used as monotherapy and when used in combination with other antidiabetic treatments. Throughout all phases of clinical studies, dapagliflozin was generally well tolerated. Increased events suggestive of urinary tract and genital infections have been reported; most resolved with conventional treatment. Unexpected numerical imbalances between dapagliflozin and comparator were noted for breast and bladder cancers. The potential for increased cancer risk with dapagliflozin needs to be further assessed.
Assuntos
Diabetes Mellitus Tipo 2/tratamento farmacológico , Descoberta de Drogas , Glucosídeos/uso terapêutico , Inibidores do Transportador 2 de Sódio-Glicose , Animais , Compostos Benzidrílicos , Diabetes Mellitus Tipo 2/metabolismo , Descoberta de Drogas/métodos , Humanos , Transportador 2 de Glucose-Sódio/metabolismo , Resultado do TratamentoRESUMO
Hyperglycemia is a major risk factor for both the microvascular and macrovascular complications in patients with type 2 diabetes. This review summarizes the cardiovascular results of large outcomes trials in diabetes and presents new evidence on the role of hyperglycemia, with particular emphasis on postprandial hyperglycemia, in adverse cardiovascular outcomes in patients with type 2 diabetes. Treatment options, including the new dipeptidyl peptidase-4 inhibitors and glucagon-like peptide-1 mimetics that primarily target postprandial hyperglycemia, are also discussed. Hyperglycemia increases cardiovascular mortality, and reducing hyperglycemia lowers cardiovascular risk parameters. Control of both fasting and postprandial hyperglycemia is necessary to achieve optimal glycated hemoglobin control. Therefore, anti-hyperglycemic agents that preferentially target postprandial hyperglycemia, along with those that preferentially target fasting hyperglycemia, are strongly suggested to optimize individual diabetes treatment strategies and reduce complications.
Assuntos
Diabetes Mellitus Tipo 2/complicações , Angiopatias Diabéticas/etiologia , Hiperglicemia/complicações , Hipoglicemiantes/uso terapêutico , Angiopatias Diabéticas/prevenção & controle , Inibidores da Dipeptidil Peptidase IV/uso terapêutico , Jejum/sangue , Hemoglobinas Glicadas/metabolismo , Humanos , Hiperglicemia/sangue , Hiperglicemia/tratamento farmacológico , RiscoRESUMO
It is long known that both type 1 and type 2 diabetes can be associated with changes in gastric emptying; a number of publications have linked diabetes to delayed gastric emptying of variable severity and often with poor relationship to gastrointestinal symptomatology. In contrast, more recent studies have reported accelerated gastric emptying when adjusted for glucose concentration in patients with diabetes, indicating a reciprocal relationship between gastric emptying and ambient glucose concentrations. This review proposes that gastroparesis or gastroparesis diabeticorum, a severe condition characterized by a significant impairment of gastric emptying accompanied by severe nausea, vomiting, and malnutrition, is often overdiagnosed and not well contrasted with delays in gastric emptying. The article offers a clinically relevant definition of gastroparesis that should help differentiate this rare condition from (often asymptomatic) delays in gastric emptying. The fact that delayed gastric emptying can also be observed in non-diabetic individuals under experimental conditions in which hyperglycaemia is artificially induced suggests that a delay in gastric emptying rate when blood glucose concentrations are high is actually an appropriate physiological response to hyperglycaemia, slowing further increases in blood glucose. The article discusses the strengths and weaknesses of various methodologies for assessing gastric emptying, especially with respect to the diabetes population, and reviews newer diabetes therapies that decelerate the rate of gastric emptying. These therapies may be a beneficial tool in managing postprandial hyperglycaemia because they attenuate rapid surges in glucose concentrations by slowing the delivery of meal-derived glucose.
Assuntos
Complicações do Diabetes/fisiopatologia , Diabetes Mellitus/fisiopatologia , Esvaziamento Gástrico/fisiologia , Gastroparesia/diagnóstico , Gastroparesia/terapia , Glicemia/metabolismo , Diabetes Mellitus/tratamento farmacológico , Diabetes Mellitus/metabolismo , Diagnóstico Diferencial , Esvaziamento Gástrico/efeitos dos fármacos , Gastroparesia/etiologia , Gastroparesia/fisiopatologia , HumanosRESUMO
Coronary heart disease (CHD) risk in 20 non-diabetic women with and 20 without a distant history of gestational diabetes (hGDM), matched on age, body mass index, and time since GDM-affected pregnancy, was compared in a case control study. Women with an hGDM had lower high-density lipoprotein cholesterol (HDL-c), p = .02, and higher triglycerides, p < or = .001, versus controls. The combination of high triglycerides and low HDL-c occurred in 25% of hGDM cases versus 0% of controls, p = .01. Two-hour post-load glucose indicated that 45% of hGDM cases were pre-diabetic versus 20% of controls, p < or = .05. Non-diabetic women with a distant hGDM are at increased risk for DM and may be at increased risk for CHD.
Assuntos
Doença das Coronárias/etiologia , Complicações do Diabetes/complicações , Diabetes Gestacional/etiologia , Adulto , Estudos de Casos e Controles , Distribuição de Qui-Quadrado , Colesterol/sangue , HDL-Colesterol/sangue , Doença das Coronárias/sangue , Doença das Coronárias/epidemiologia , Complicações do Diabetes/sangue , Complicações do Diabetes/epidemiologia , Diabetes Mellitus Tipo 2/etiologia , Diabetes Gestacional/sangue , Diabetes Gestacional/epidemiologia , Feminino , Humanos , Modelos Logísticos , Pessoa de Meia-Idade , Análise Multivariada , Obesidade/complicações , Estado Pré-Diabético/etiologia , Gravidez , Medição de Risco , Fatores de Risco , Fatores de Tempo , Triglicerídeos/sangueRESUMO
OBJECTIVE: Slowing of gastric emptying by hyperglycemia, a physiological response to minimize postprandial hyperglycemia, may be impaired in patients with type 1 diabetes. The causes and consequences on glucose homeostasis are unknown. RESEARCH DESIGN AND METHODS: Consequences of euglycemia- and hyperglycemia-induced changes in gastric emptying on postprandial glucose fluxes and excursions were studied in 10 healthy subjects and 15 type 1 diabetic subjects after ingestion of a mixed meal using the double isotope approach ([6,6-(2)H(2)] and [1-(13)C]glucose) and scintigraphic measurements of gastric emptying. RESULTS: Gastric emptying was greater in type 1 diabetic subjects (90-120 min, P < 0.03), and 50% retention times were comparable in healthy subjects and type 1 diabetic subjects (167 +/- 8 vs. 152 +/- 10, P = 0.32). Hyperglycemia markedly delayed gastric emptying in healthy subjects but did not alter it in type 1 diabetic subjects (50% retention time 222 +/- 18 vs. 167 +/- 8 min, P = 0.003 and 148 +/- 9 vs. 152 +/- 10 min, P = 0.51). Plasma islet amyloid polypeptide (IAPP) increased approximately fourfold in healthy subjects (P < 0.001), whereas it was undetectable in type 1 diabetic subjects. IAPP replacement, using the analog pramlintide, in type 1 diabetic subjects slowed gastric emptying to a comparable extent, as did hyperglycemia in healthy subjects (P < 0.14), and greatly reduced postprandial hyperglycemia (P < 00.1). Meal-derived glucose appearance in plasma (10.7 +/- 0.5 vs. 6.8 +/- 0.7 mumol . kg(-1) . min(-1), P < 0.001) was reduced, and splanchnic glucose sequestration increased (14.0 +/- 3.0 vs. 25.0 +/- 6.0%, P = 0.04). CONCLUSIONS: In patients with type 1 diabetes the ability to delay gastric emptying in response to hyperglycemia is impaired. This impairment contributes to exaggerated rates of meal-derived glucose appearance and, ultimately, postprandial glucose excursions.
Assuntos
Amiloide/sangue , Diabetes Mellitus Tipo 1/sangue , Esvaziamento Gástrico/fisiologia , Hiperglicemia/fisiopatologia , Adulto , Diabetes Mellitus Tipo 1/fisiopatologia , Feminino , Humanos , Polipeptídeo Amiloide das Ilhotas Pancreáticas , MasculinoRESUMO
OBJECTIVE: To examine the effect of aging on insulin secretion (first- and second-phase insulin release) and insulin sensitivity in people with normal glucose tolerance (NGT) or impaired glucose tolerance (IGT). RESEARCH DESIGN AND METHODS: First- and second-phase insulin secretion and insulin sensitivity were assessed in hyperglycemic clamp experiments in 266 individuals with NGT and 130 individuals with IGT, ranging in age from approximately 20 to approximately 70 years. Changes in beta-cell function were compared using the disposition index to adjust for differences in insulin sensitivity. RESULTS: As expected, both phases of insulin release and insulin sensitivity were reduced in individuals with IGT (all P < 0.01). Insulin sensitivity was not independently correlated with age in either group. In people with NGT, the disposition index for first- and second-phase insulin release decreased similarly at a rate of approximately 0.7% per year. In people with IGT, the disposition indexes for first- and second-phase insulin release decreased at greater rates ( approximately 2.2 and 1.4% per year, P = 0.002 and 0.009, respectively, vs. NGT), with the decrease in first phase being greater than that of second phase (P = 0.025). CONCLUSIONS: Insulin secretion (both first and second phase) normally decreases at a rate of approximately 0.7% per year with aging; this decrease in beta-cell function is accelerated about two-fold in people with impaired glucose tolerance-first phase to a greater extent than second phase. Finally, aging per se has no effect on insulin sensitivity independent of changes in body composition.
Assuntos
Envelhecimento , Glicemia/metabolismo , Intolerância à Glucose/sangue , Células Secretoras de Insulina/metabolismo , Adulto , Idoso , Índice de Massa Corporal , Feminino , Intolerância à Glucose/metabolismo , Intolerância à Glucose/fisiopatologia , Homeostase/fisiologia , Humanos , Insulina/sangue , Células Secretoras de Insulina/patologia , Masculino , Pessoa de Meia-IdadeRESUMO
BACKGROUND: Decisions regarding diabetes management traditionally have been driven by the results of fasting plasma glucose measurement or measurement of glycosylated hemoglobin (A1C), yet glycemic control remains far from optimal in many individuals with diabetes. Mounting evidence implicates glycemic variability, manifested predominantly as postprandial glycemic spikes, as a key factor in the development of macrovascular complications. Recent studies suggest that newer therapies specifically targeting postprandial hyperglycemia can significantly reduce postprandial glucose levels and improve overall glycemic control. METHODS: A Medline search was performed using the term 'postchallenge' or 'postprandial', together with glucose or diabetes. After excluding review articles and case studies, we reviewed primary articles, meta-analyses, and references therein and selected those that best addressed this topic. Selection bias may be considered a potential limitation of this approach. FINDINGS: Although not conclusively demonstrated by prospective studies, a wealth of evidence suggests that postprandial hyperglycemia should not be ignored as an important target for preventing complications of diabetes. CONCLUSIONS: Improved detection and management of postprandial hyperglycemia and glycemic variability is necessary to optimize glycemic control. Meal-based self-monitoring of blood glucose (SMBG) has been shown to improve glycemic control as part of a comprehensive management strategy by helping patients understand the effects of food choices, physical activity, and medications on blood glucose concentrations. SMBG can also help healthcare professionals recognize postprandial hyperglycemia, guide therapeutic adjustments and receive more timely feedback regarding medication changes. The arrival of new therapies that specifically target postprandial hyperglycemia offer healthcare professionals the opportunity to optimally manage diabetes.
Assuntos
Automonitorização da Glicemia/métodos , Glicemia/análise , Diabetes Mellitus/sangue , Período Pós-Prandial , Vasos Sanguíneos/fisiopatologia , Humanos , Fatores de RiscoRESUMO
The hyperglycemic activity of pancreatic extracts was encountered some 80 yr ago during efforts to optimize methods for the purification of insulin. The hyperglycemic substance was named "glucagon," and it was subsequently determined that glucagon is a 29-amino acid peptide synthesized and released from pancreatic alpha-cells. This article begins with a brief overview of the discovery of glucagon and the contributions that somatostatin and a sensitive and selective assay for pancreatic (vs. gut) glucagon made to understanding the physiological and pathophysiological roles of glucagon. Studies utilizing these tools to establish the function of glucagon in normal nutrient homeostasis and to document a relative glucagon excess in type 2 diabetes mellitus (T2DM) and precursors thereof are then discussed. The evidence that glucagon excess contributes to the development and maintenance of fasting hyperglycemia and that failure to suppress glucagon secretion contributes to postprandial hyperglycemia is then reviewed. Although key human studies are emphasized, salient animal studies highlighting the importance of glucagon in normal and defective glucoregulation are also described. The past eight decades of research in this area have led to development of new therapeutic approaches to treating T2DM that have been shown to, or are expected to, improve glycemic control in patients with T2DM in part by improving alpha-cell function or by blocking glucagon action. Accordingly, this review ends with a discussion of the status and therapeutic potential of glucagon receptor antagonists, alpha-cell selective somatostatin agonists, glucagon-like peptide-1 agonists, and dipeptidyl peptidase-IV inhibitors. Our overall conclusions are that there is considerable evidence that relative hyperglucagonemia contributes to fasting and postprandial hyperglycemia in patients with T2DM, and there are several new and emerging pharmacotherapies that may improve glycemic control in part by ameliorating the hyperglycemic effects of this relative glucagon excess.
Assuntos
Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/fisiopatologia , Células Secretoras de Glucagon/fisiologia , Receptores de Glucagon/antagonistas & inibidores , Animais , Jejum/fisiologia , Glucagon/fisiologia , Humanos , Hiperglicemia/tratamento farmacológico , Hiperglicemia/fisiopatologia , Período Pós-Prandial/fisiologiaRESUMO
OBJECTIVE: HbA1c values reflect overall glycemic exposure over the past 2-3 months and are determined by both fasting (FPG) and postprandial plasma glucose (PPG) levels. Cross-sectional studies suggest that attainment of HbA1c goals requires specific targeting of postprandial hyperglycemia. RESEARCH DESIGN AND METHODS: We undertook a prospective intervention trial to assess the relative contribution of controlling FPG and PPG for achieving recommended HbA1c goals. One hundred and sixty-four patients (90 male and 74 female) with unsatisfactory glycemic control (HbA1c >/=7.5%) were enrolled in an individualized forced titration intensified treatment program. RESULTS: After 3 months HbA1c levels decreased from 8.7+/-0.1 to 6.5+/-0.1% (p<0.001); FPG decreased from 174+/-4 to 117+/-2mg/dl (p<0.001); PPG decreased from 224+/-4 to 159+/-3mg/dl (p<0.001) and daylong hyperglycemia (average of premeal, postprandial and bedtime plasma glucose excluding FPG) decreased from 199+/-4 to 141+/-2mg/dl (p<0.0001). Patients' weight remained unchanged (84.0+/-1.4kg versus 82.9+/-1.5kg, p=0.36). No severe hypoglycemia occurred. Only 64% of patients achieving FPG targets of <100mg/dl achieved an HbA1c target of <7% whereas 94% of patients achieving the postprandial target of <140mg/dl did. Decreases in PPG accounted for nearly twice as much for the decreases in HbA1c as did decreases in FPG. PPG accounted approximately 80% of HbA1c when HbA1c was <6.2% and only about 40% when HbA1c was above 9.0%. CONCLUSIONS: Control of fasting hyperglycemia is necessary but usually insufficient for achieving HbA1c goals <7%. Control of postprandial hyperglycemia is essential for achieving recommended HbA1c goals.
Assuntos
Glicemia/metabolismo , Diabetes Mellitus Tipo 2/sangue , Jejum/fisiologia , Hemoglobinas Glicadas/metabolismo , Período Pós-Prandial/fisiologia , Glicemia/análise , Índice de Massa Corporal , Diabetes Mellitus Tipo 2/tratamento farmacológico , Dieta para Diabéticos , Quimioterapia Combinada , Feminino , Humanos , Hipoglicemiantes/uso terapêutico , Masculino , Metformina/uso terapêutico , Pessoa de Meia-IdadeRESUMO
The risk for cardiovascular disease (CVD) is multifactorial and includes such risk factors as diabetes, hypertension, smoking, and dyslipidemia. Thus, targeting the hyperglycemia in type 2 diabetes mellitus (DM) alone will not eliminate all of the excess cardiovascular risk; rather aggressive treatment is needed for all of the modifiable cardiometabolic risk factors. Therapeutic lifestyle change is considered primary therapy for hyperglycemia in type 2 DM. Currently, however, the focus in treatment is on preventing CVD rather than controlling glucose, lipid, or blood pressure (BP) levels. The American Diabetes Association guidelines identify low-density lipoprotein cholesterol as the first priority of lipid lowering, with optimal level set at <100 mg/dL (2.6 mmol/L). To reach the target BP level of <130/85 mm Hg, >65% of patients with DM and hypertension will require 2 or more different antihypertensive drugs. Strategies that combine thiazolidinediones and statins may have complementary effects on cardiovascular risk-factor profiles in type 2 DM, in addition to controlling glycemia. Despite the range of treatment options available, therapeutic agents that target new steps in the progression of CVD are needed, as patients with type 2 DM remain at increased risk and many do not achieve therapeutic targets with the drugs available.
Assuntos
Doenças Cardiovasculares/metabolismo , Complicações do Diabetes/fisiopatologia , Diabetes Mellitus Tipo 2/fisiopatologia , Doenças Cardiovasculares/etiologia , Doenças Cardiovasculares/fisiopatologia , Ácido Clofíbrico/uso terapêutico , Doença da Artéria Coronariana/fisiopatologia , Complicações do Diabetes/epidemiologia , Diabetes Mellitus Tipo 2/epidemiologia , Progressão da Doença , Dislipidemias , Humanos , Fatores de Risco , Comportamento de Redução do Risco , Tiazolidinedionas/uso terapêuticoRESUMO
Cardiovascular disease is the leading cause of morbidity and mortality among patients with diabetes. Having diabetes is now recognized as conferring the same risk for cardiovascular disease as hyperlipidemia, hypertension, and smoking. HbA1c levels are the primary indicator of diabetes control and overall glycemic exposure. And recent research has pointed to postprandial hyperglycemia as conferring a greater risk of cardiovascular disease than elevated fasting plasma glucose levels. Unfortunately, clinicians sometimes forget that elevated HbA1c levels can arise from both fasting hyperglycemia and postprandial hyperglycemia. This is particularly important to remember when treating patients whose HbA1c levels may be higher than the desired target while fasting plasma glucose test results are within reference range. This article reviews the evidence supporting the view that postprandial hyperglycemia is a risk factor for cardiovascular disease and therefore should be controlled. Case studies are presented to aid clinicians in helping patients learn how to measure and control their postprandial glucose levels.
Assuntos
Doenças Cardiovasculares/prevenção & controle , Diabetes Mellitus Tipo 2/sangue , Angiopatias Diabéticas/prevenção & controle , Hiperglicemia/prevenção & controle , Período Pós-Prandial , Idoso , Doenças Cardiovasculares/epidemiologia , Diabetes Mellitus Tipo 2/complicações , Angiopatias Diabéticas/sangue , Feminino , Hemoglobinas Glicadas/análise , Humanos , Masculino , Pessoa de Meia-IdadeRESUMO
OBJECTIVE: To review the role of postprandial hyperglycemia in the development of type 2 diabetes mellitus and cardiovascular disease. METHODS: The pathogenic mechanisms involved in the deterioration of glucose tolerance are discussed, and findings from relevant epidemiologic and clinical interventional studies are presented. RESULTS: It is now well established that hyperglycemia is an independent risk factor for cardiovascular disease, with no apparent threshold. In clinical practice, glycemic exposure is measured by hemoglobin A1c levels. These values reflect the contribution of fasting and postprandial plasma glucose levels during the previous 2 to 3 months. Epidemiologic studies have indicated that, at hemoglobin A1c levels (5.5%) already associated with a substantially increased risk for cardiovascular mortality, fasting plasma glucose levels are generally normal. These observations implicate isolated postprandial hyperglycemia as a cardiovascular risk factor. Controlled interventional clinical trials have found that reduction of postprandial hyperglycemia decreases cardiovascular events or surrogates thereof. CONCLUSION: Postprandial hyperglycemia should be considered a cardiovascular risk factor similar to hypertension, hyperlipidemia, and smoking; accordingly, it should be monitored and treated.
Assuntos
Doenças Cardiovasculares/etiologia , Diabetes Mellitus Tipo 2/etiologia , Alimentos , Hiperglicemia/complicações , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/prevenção & controle , Ensaios Clínicos como Assunto , Diabetes Mellitus Tipo 2/epidemiologia , Jejum , Intolerância à Glucose/diagnóstico , Hemoglobinas Glicadas/análise , Humanos , Hiperglicemia/tratamento farmacológico , Hiperglicemia/epidemiologia , Fatores de RiscoRESUMO
In type 2 diabetes mellitus (T2DM), little is known about hormonal responses to hypoglycemia. In particular, beta-cell responses to hypoglycemia have not been carefully investigated and potentially because of confounding factors or insufficient power, conflicting data have been obtained regarding growth hormone responses. We therefore compared hormonal responses including rates of insulin secretion during a 2-hour hyperinsulinemic hypoglycemic clamp in a relatively large number of nondiabetic (n=21) and moderately insulin-deficient subjects with T2DM (homeostasis model assessment of beta-cell function [HOMA-%B], 751+/-160 vs 1144+/-83 [pmol/L]/[mmol/L], P<.04) (n=14) matched for age, sex, and body mass index. Subjects with T2DM were excluded for antecedent hypoglycemia, and baseline glycemia was controlled by a variable infusion of insulin overnight. Although both groups of subjects had indistinguishable plasma glucose levels at baseline and virtually identical levels of plasma insulin and glucose throughout the hypoglycemic clamp, insulin secretion decreased more slowly in the subjects with T2DM. The time required for insulin secretion to decline to half its baseline level was markedly increased (38.9+/-4.9 vs 22.3+/-1.3 minutes [SD], P<.01), and insulin secretion decreased to a lesser extent (-0.79+/-0.17 vs -1.51+/-0.09 [pmol/L]/kg per minute, P<.002). Moreover, responses of glucagon (28.3+/-7.3 vs 52.8+/-7.0 ng/L, P<.05) and growth hormone (2.9+/-0.8 vs 6.3+/-0.9 ng/mL, P<.04) were reduced in the subjects with T2DM, whereas responses of epinephrine, norepinephrine, and cortisol were similar to those in nondiabetic subjects (all P>0.6). We conclude that multiple defects exist in hormonal responses to hypoglycemia in T2DM with moderate beta-cell failure. These include delayed and reduced decreases in insulin secretion, and impaired increases of plasma glucagon and growth hormone.