Practical Review of Oral Antihyperglycemic Agents for Type 2 Diabetes Mellitus

Pharmacological evaluation of medicinal plants with antidiabetic activities in Ethiopia: A review

Diabetes mellitus is a serious, chronic disease that occurs either when the pancreas does not produce enough insulin, or when the body can't effectively use insulin. Herbal medicines have been commonly used by diabetic patients for the treatment of diabetes mellitus. To include findings from different studies, publications related to in vivo and invitro antidiabetic activities of medicinal plants in Ethiopia were searched from different databases, such as Web of Science, Google Scholar, Medline, Scopus, and PubMed, using English key terms. Different medicinal plant parts were used experimentally for antidiabetic effects in Ethiopia. Among these, leaves (69%) were the most commonly investigated medicinal plant parts followed by roots (14%) and seeds (7%). Most of the investigations were completed with hydro-methanolic extracts to obtain a higher percentage of yield. Medicinal plants such as Thymus schemperi R, Thymus vulgaris L, Hagenia abyssinica, Aloe megalacantha baker, Aloe moticola Reyonolds, Aloe pulecherrima Gilbert & sebseb, Bersama abyssinica fresen, and Rubus Erlangeri Engl have shown in vitro α-amylase inhibitory activity. However, only Hagenia abyssinica, Thymus schemperi R, and Thymus vulgaris L have exhibited α-glucosidase inhibitory activity. Likewise, only the extract of Aloe pulecherrima Gilbert & sebseb posses’ maltase and sucrose inhibitory activity. In vivo antidiabetic activity were conducted for the extract of medicinal plants such as A. remota, S. rebaudiani, T. schemperi, T. vulgaris, H. abyssinica, C. aurea, D. stramonium, A. megalacantha, A. moticola, A.integrifolia, A. pulecherrima, B. grandiflorum, B. abyssinica, P. schimperiana, M. stenopetala, C. aure, J. schimperiana, T. brownie, C. macrostachys, I. spicata, O. integrifolia, C. abyssinica, R. Erlangeri, L. culinaris, A. camperi, A. polystachyus, A. ilicifalius, C. tomentosa, and C. Edulis. This review gives collective evidence on the potential antidiabetic activities of medicinal plants in Ethiopia. Moreover, further studies are recommended to substantiate the use of these medicinal plants as an antidiabetic agent.

Prevalence and associated factors of herbal medicine use among adult diabetes mellitus patients at government hospital, Ethiopia: An institutional-based cross-sectional study

BACKGROUND

Diabetes mellitus (DM) is a group of metabolic diseases characterized by hyperglycemia resulting from defects in insulin secretion, insulin action, or both. Thus, this study aimed to assess the prevalence and factors associated with HM use among DM patients.

METHODS

A hospital-based cross-sectional study was conducted on 395 diabetic patients visiting the diabetes care service of Debre Tabor General Hospitalfrom August 1 to September 28, 2020. Interview guided self-administered questionnaire was used for data collection.

RESULTS

Out of 395 diabetic patients, 231(58.5%) participants were used herbal medicine. The most dominant herbal products used were M.stenoptela (53.2%), N. sativa (42.0%), Z. officinale (32.5%), A. sativum (20.8%), A. vera (13.4%), P.gracilis(10.4%), T.schimperi(7.5%), V. amygdalina (5.2%), T. foenumgraecum(3.5%),and D.penninervum(2.2%).The odds of HM use in female participants were 1.98 times (AOR=1.98, 95% CI=1.72, 3.25) higher compared to male participants. The odds of HM use among participants who develop DM complications were 1.77 times (AOR=1.77, 95% CI=1.03, 2.83) higher than in participants without DM complications. The odds of HM use among participants with a family history of DM were 2.89 times (AOR=2.89, 95% CI=1.42, 3.19) higher than in participants without a family history of DM.

CONCLUSION

The prevalence of herbal medicine use among diabetic patients was high. Educational level, gender, residence, educational level, duration of DM, presence of DM complication, and family history of DMwere the independent predictors' of HM use.

Evaluation of In Vivo Antidiabetic, In Vitro α-Amylase Inhibitory, and In Vitro Antioxidant Activity of Leaves Crude Extract and Solvent Fractions of Bersama abyssinica Fresen (Melianthaceae)

Background.

The leaves of Bersama abyssinica are used for the treatment of diabetes mellitus in folk medicine system of Ethiopia. The present study was done based on the traditional claim of B abyssinica for the treatment of diabetes mellitus.

Methods.

The α-amylase inhibition and antioxidant activities of B abyssinica extracts were evaluated by using 3,5-dinitrosalicylic acid method and diphenyl-2-picrylhydrazyl assay model, respectively. Blood glucose lowering activity of the extracts was studied in 4 animal models; normoglycemic, oral glucose loaded, and streptozotocin-induced diabetic mice models.

Results.

Among the extracts, the crude extract showed the highest α-amylase enzyme inhibition activity with an IC₅₀ of 6.57 μg/mL. The water fraction showed the strongest antioxidant activity with an IC₅₀ of 3.43 μg/mL. The crude extract at doses of 200, and 400 mg/kg showed significant (P < .05) hypoglycemic activity in normoglycemic mice. All doses of the crude extract significantly (P < .05) reduced blood glucose levels of oral glucose-loaded mice. In streptozotocin-induced diabetic mice models, both the crude and solvent fractions showed a significant (P < .05) blood glucose lowering effect as compared with the negative control group post 8 hour treatment.

Conclusion.

The results demonstrated the beneficial biochemical effects of B abyssinica extract by inhibiting α-amylase and scavenging the free radicals. The crude extract and solvent fractions of B abyssinica had significant blood glucose lowering effect in all animal models.

Alotaibi A, Al-zharani M, Ziyyat A, Mekhfi H, Legssyer A, Aziz M, Bnouham M. Opuntia dillenii (Ker Gawl.) Haw., Seeds Oil Antidiabetic Potential Using In Vivo, In Vitro, In Situ, and Ex Vivo Approaches to Reveal Its Underlying Mechanism of Action

Opuntia dillenii Ker Gawl. is one of the medicinal plants used for the prevention and treatment of diabetes mellitus (DM) in Morocco. This study aims to investigate the antihyperglycemic effect of Opuntia dillenii seed oil (ODSO), its mechanism of action, and any hypoglycemic risk and toxic effects. The antihyperglycemic effect was assessed using the OGTT test in normal and streptozotocin (STZ)-diabetic rats. The mechanisms of action were explored by studying the effect of ODSO on the intestinal absorption of d-glucose using the intestinal in situ single-pass perfusion technique. An Ussing chamber was used to explore the effects of ODSO on intestinal sodium-glucose cotransporter 1 (SGLT1). Additionally, ODSO’s effect on carbohydrate degrading enzymes, pancreatic α-amylase, and intestinal α-glucosidase was evaluated in vitro and in vivo using STZ-diabetic rats. The acute toxicity test on mice was performed, along with a single-dose hypoglycemic effect test. The results showed that ODSO significantly attenuated the postprandial hyperglycemia in normal and STZ-diabetic rats. Indeed, ODSO significantly decreased the intestinal d-glucose absorption in situ. The ex vivo test (Ussing chamber) showed that the ODSO significantly blocks the SGLT1 (IC₅₀ = 60.24 µg/mL). Moreover, ODSO indu\ced a significant inhibition of intestinal α-glucosidase (IC₅₀ = 278 ± 0.01 µg/mL) and pancreatic α-amylase (IC₅₀ = 0.81 ± 0.09 mg/mL) in vitro. A significant decrease of postprandial hyperglycemia was observed in sucrose/starch-loaded normal and STZ-diabetic ODSO-treated rats. On the other hand, ODSO had no risk of hypoglycemia on the basal glucose levels in normal rats. Therefore, no toxic effect was observed in ODSO-treated mice up to 7 mL/kg. The results of this study suggest that ODSO could be suitable as an antidiabetic functional food.

Randomized double-blinded pilot clinical study of the antidiabetic activity of Balanites aegyptiaca and UPLC-ESI-MS/MS identification of its metabolites

CONTEXT

Balanites aegyptiaca Del. (Zygophyllaceae) fruits are traditionally known for the treatment of hyperglycaemia. Several in vitro and in vivo studies proposed some mechanisms of action. However, clinical trials in human beings were never reported to date.

OBJECTIVES

To investigate the antidiabetic efficacy of the 70% ethanol extract of the pericarps of B. aegyptiaca (BE) within a nutritional intervention in elderly people.

MATERIALS AND METHODS

Ultra-performance electrospray ionization-mass spectroscopy (UPLC-ESI-MS/MS) analysis was used for metabolic profiling of BE which was incorporated in hard gelatine capsules (400 mg/day) and tested on 30 type 2 diabetes (T2D) Egyptian patients for 8 weeks. According to sex, age and body mass index participants were divided into two equivalent groups, placebo and treatment.

RESULTS

Thirteen compounds were identified in BE using UPLC-ESI-MS/MS analysis among which five steroidal saponins, seven phenolic compounds and a sterol glucoside. At the end of the 8-week treatment, the treated group showed 26.88% decrease in 2 h postprandial plasma glucose relative to 2.6% increase in the placebo group, while fasting plasma glucose was reduced to 10.3%. Treatment with BE capsules for 8 weeks produced significant reduction in the plasma triglyceride, total cholesterol and low-density lipoprotein cholesterol by 9.0, 12.76 and 21.35%, respectively, with 29.8% increase in the high-density lipoprotein cholesterol. Plasma alanine transaminase and aspartate transaminase were reduced by 42.6 and 43.3%, respectively.

DISCUSSION AND CONCLUSION

Administration of the BE capsules to T2D resulted in significant improvements in the glycaemic markers and the lipid profile, without adverse effects or hypoglycaemia.

Antidiabetic activity and phytochemical screening of extracts of the leaves of Ajuga remota Benth on alloxan-induced diabetic mice

Background

Ajuga remota Benth is traditionally used in Ethiopia for the management of diabetes mellitus. Since this claim has not been investigated scientifically, the aim of this study was to evaluate the antidiabetic effect and phytochemical screening of the aqueous and 70% ethanol extracts on alloxan-induced diabetic mice.

Methods

After acute toxicity test, the Swiss albino mice were induced with alloxan to get experimental diabetes animals. The fasting mean blood glucose level before and after treatment for two weeks in normal, diabetic untreated and diabetic mice treated with aqueous and 70% ethanol extracts were performed. Data were statistically evaluated by using Statistical Package for the Social Sciences software version 20. P-value <0.05 was considered statistically significant.

Results

The medium lethal doses (LD₅₀) of both extracts were higher than 5000 mg/kg, indicating the extracts are not toxic under the observable condition. Aqueous extracts of A.remota (300 mg/kg and 500 mg/kg body weight) reduced elevated blood glucose levels by 27.83 ± 2.96% and 38.98 ± 0.67% (P < 0.0001), respectively while the 70% ethanol extract caused a reduction of 27.94 ± 1.92% (300 mg/kg) & 28.26 ± 1.82% (500 mg/kg). Treatment with the antidiabetic drug, Glibenclamide (10 mg/kg body weight) lowered blood glucose level by 51.06% (p < 0.05). Phytochemical screening of both extracts indicated the presence of phenolic compounds, flavonoids, saponins, tannins, and steroids, which might contribute to the antidiabetic activity. The extracts, however, did not contain alkaloids and anthraquinones.

Conclusion

The aqueous extract (500 mg/kg) showed the highest percentage reduction in blood glucose levels and the ability of A. remota extracts in reducing blood glucose levels presumably due to the presence of antioxidant constituents such as flavonoids. The effect of the extract supported the traditional claim of the plant.

Nutritional composition of Stevia rebaudiana, a sweet herb, and its hypoglycaemic and hypolipidaemic effect on patients with non-insulin dependent diabetes mellitus

BACKGROUND

The prevalence of diabetes is rapidly rising all over the globe at an alarming rate. India shelters the highest number of diabetics and is thus known as the 'Diabetes Capital of the World'. The chemical management of diabetes has side effects and hence the present study was undertaken to assess the hypoglycaemic and hypolipidaemic effect of Stevia rebaudiana in patients with type 2 diabetes, non-insulin dependent diabetes mellitus (NIDDM). Its nutritional composition and use as a sweetener substitute were also assessed.

RESULTS

Chemical analysis of dried Stevia leaf powder revealed it to be a nutritious herb with a good iron and fibre content. Intervention trials in diabetics revealed that it significantly lowered fasting and post-prandial blood glucose levels. The serum triglycerides and VLDL-C levels were also significantly reduced.

CONCLUSION

Hence it can be said that Stevia can safely be used as an anti-diabetic herb, as a sweetener substitute and may help to prevent cardiovascular diseases in patients with long-standing diabetes. © 2016 Society of Chemical Industry.

Sensitive colorimetric assays for α-glucosidase activity and inhibitor screening based on unmodified gold nanoparticles

A colorimetric sensor has been developed in this work to sensitively detect α-glucosidase activity and screen α-glucosidase inhibitors (AGIs) utilizing unmodified gold nanoparticles (AuNPs). The sensing strategy is based on triple-catalytic reaction triggered by α-glucosidase. In the presence of α-glucosidase, aggregation of AuNPs is prohibited due to the oxidation of cysteine to cystine in the system. However, with addition of AGIs, cysteine induced aggregation of AuNPs occurs. Thus, a new method for α-glucosidase activity detection and AGIs screening is developed by measuring the UV-vis absorption or visually distinguishing. A well linear relation is presented in a range of 0.0025-0.05 U mL(-1). The detection limit is found to be 0.001 U mL(-1) for α-glucosidase assay, which is one order of magnitude lower than other reports. The IC50 values of four kinds of inhibitors observed with this method are in accordance with other reports. The using of unmodified AuNPs in this work avoids the complicated and time-consuming modification procedure. This simple and efficient colorimetric method can also be extended to other enzymes assays.

Gynostemma pentaphyllum Tea Improves Insulin Sensitivity in Type 2 Diabetic Patients

Aims. To evaluate the effect of the traditional Vietnamese herb Gynostemma pentaphyllum tea on insulin sensitivity in drug-naïve type 2 diabetic patients. Methods. Patients received GP or placebo tea 6 g daily for four weeks and vice versa with a 2-week wash-out period. At the end of each period, a somatostatin-insulin-glucose infusion test (SIGIT) was performed to evaluate the insulin sensitivity. Fasting plasma glucose (FPG), HbA(1C), and oral glucose tolerance tests and insulin levels were measured before, during, and after the treatment. Results. FPG and steady-state plasma glucose (SIGIT mean) were lower after GP treatment compared to placebo treatment (P < 0.001). The levels of FPG in the control group were slightly reduced to 0.2 ± 1.5 versus 1.9 ± 1.0 mmol/L in GP group (P < 0.001), and the effect on FPG was reversed after exchanging treatments. The glycometabolic improvements were achieved without any major change of circulating insulin levels. There were no changes in lipids, body measurements, blood pressure, and no reported hypoglycemias or acute adverse effects regarding kidney and liver parameters. Conclusion. The results of this study suggested that the GP tea exerted antidiabetic effect by improving insulin sensitivity.

Novel fluorescent biosensor for α-glucosidase inhibitor screening based on cationic conjugated polymers

A new fluorescent biosensor has been designed to screen α-glucosidase inhibitors (AGIs) sensitively by utilizing signal amplification effect of conjugated polymers. The fluorescence of cationic poly(fluorenylene phenylene) (PFP) was quenched in the presence of para-nitrophenyl-α-d-glucopyranoside and α-glucosidase, and turned on upon addition of AGIs. Thus, a new method was developed for AGIs screening based on the fluorescence turn-off/turn-on. The IC(50) values obtained for inhibitors were compared with that reported using absorption spectroscopy. All results present the new method is more sensitive and promising in screening AGIs and inhibitors of other enzymes whose hydrolysis product is 4-nitrophenol.

Randomized and double-blinded pilot clinical study of the safety and anti-diabetic efficacy of the Rauvolfia-Citrus tea, as used in Nigerian traditional medicine

AIM OF THE STUDY

The aim of this randomized and double blinded pilot clinical trial was to investigate the anti-diabetic efficacy of the Rauvolfia-Citrus (RC) tea in humans. We have earlier shown that a combination of calorie-restriction and chronic administration of the RC tea to the genetic diabetic (BKS-db) mice resulted in the normalization of blood sugar, reduction in lipid accumulated in the mice eyes and prevention of the degeneration of the otherwise brittle BKS-db pancreas. The tea is made by boiling foliage of Rauvolfia vomitoria and fruits of Citrus aurantium and is used to treat diabetes in Nigerian folk medicine.

MATERIALS AND METHODS

The RC tea was produced using the Nigerian traditional recipe and tested in the traditional dosage on 23 Danish type 2 diabetes (T2D) patients. The participants were divided into two equivalent groups after stratification by sex, age and BMI, in a 4-month double-blinded, placebo-controlled and randomized clinical trial. Most of the study subjects (19/23) were using oral anti-diabetic agents (OADs). Mean disease duration was 6±4.6 years, mean age was 64±7 years and mean BMI was 28.7±3.8 kg/m(2). Prior to starting the treatment, the participants received individual dietician consultations.

RESULTS

At the end of the 4-month treatment period, the treated group showed an 11% decrease in 2-h postprandial plasma glucose relative to the 3% increase in the placebo group (p=0.004). The improvement in blood glucose clearance with RC tea treatment was reflected in a 6% reduction in HbA(1c) (p=0.02) and in a 10% reduction in fasting plasma glucose (p=0.02), when comparing the post 4-month treatment to pre-treatment baseline values. Though the basal levels of phosphorylated acetyl CoA carboxylase enzyme in skeletal muscle were significantly reduced in the treated group (p=0.04), as compared to the placebo, only the pattern of reductions in the tissue fatty acids (FAs) differed in the two groups. While all types of FAs were reduced in placebo, only saturated (SFA) and monounsaturated (MUFA) FAs were reduced with treatment. Interestingly, a modest increase in the polyunsaturated FAs fraction was observed in the RC treated group. In addition, the reduction in SFA and MUFA with RC tea treatment came solely from the triglyceride fractions, as there was an increase in the skeletal muscle phospholipids.

CONCLUSIONS

Chronic administration of the RC tea to overweight T2D on OADs caused significant improvements in markers of glycaemic control and modifications to the fatty acid profile of skeletal muscle, without adverse effects or hypoglycaemia. Further exploration of the anti-diabetic effects of the RC tea is warranted.

Liquid chromatographic-tandem mass spectrometry assay for quantitation of a novel antidiabetic S002-853 in rat plasma and its application to pharmacokinetic study

A sensitive and selective LC-MS/MS method has been developed and validated for the estimation of novel antidiabetic synthetic flavonoid S002-853 in rat plasma using centchroman as an internal standard. The method involves a simple two-step liquid-liquid extraction with diethyl ether. The analyte was chromatographed on a Pierce Spheri-5, guard cyano column (30 x 4.6 mm i.d., 5 microm) with isocratic mobile phase consisting of methanol-ammonium acetate buffer (pH 4.6, 10 mm; 90 : 10, v/v) at a flow rate of 0.75 mL/min. The API 4000 triple-quadrupole LC-MS/MS system was operated under multiple reaction-monitoring mode. The ionization was performed by electrospray ionization technique in positive ion mode. The chromatographic run time was 6 min and the weighted (1/x(2)) calibration curves were linear over the range 0.78-400 ng/mL. The limit of detection and lower limit of quantification were 0.195 and 0.78 ng/mL, respectively. The intra- and inter-batch accuracy (%bias) and precision (%RSD) were found to be less than 8.47 and 11.6% respectively. The average absolute recoveries of S002-853 and internal standard from spiked plasma samples were >90%. S002-853 was stable for 8 h at ambient temperature, 4 weeks at -60 degrees C and after three freeze-thaw cycles. The assay was successfully applied to determine the pharmacokinetic parameters in male Sprague-Dawley rats after an oral dose administration at 25 mg/kg.

Integrating glycaemic variability in the glycaemic disorders of type 2 diabetes: a move towards a unified glucose tetrad concept

The high incidence of atherosclerosis and cardiovascular disease (CVD) is the leading cause of morbidity and mortality among patients with diabetes. Evidence is accumulating that postprandial hyperglycaemia is an independent risk factor for diabetes-associated complications and mortality, and that worsening diabetes control is characterized by postprandial glucose (PPG) deterioration preceding an impairment in fasting glucose levels. Postprandial and general glucose fluctuations play a major role in activating oxidative stress, leading to the endothelial dysfunction, one of the mechanisms responsible for vascular complications. Therefore, the management of PPG is key for any strategy used in the monitoring and treatment of diabetes. We recommend that any strategy aimed at controlling the glycaemic disorders associated with type 2 diabetes, and limiting the risk of complications, should target the 'glucose tetrad', which comprises the following components: HbA(1c), fasting and postprandial plasma glucose, and markers of glycaemic variability, such as the mean amplitude of glycaemic excursions (MAGE) index. This brings together, in a simple, unified concept, the conventional markers (HbA(1c) and fasting glucose) and the more recently recognized markers of glycaemic control (PPG excursions and acute glycaemic variability).

Dosing of insulin glargine in the treatment of type 2 diabetes

BACKGROUND

Type 2 diabetes is a progressive disease characterized by insulin resistance and declining beta-cell function, often leading to a requirement for insulin therapy to maintain good glycemic control and prevent diabetes-associated complications. Adequate insulin dosing is crucial to the achievement of good glycemic control with minimal hypoglycemia, and dose titration immediately following insulin initiation is needed to ensure its success. Insulin may be initiated as an add-on therapy to oral treatment using a single evening basal insulin dose and titrating according to fasting blood glucose (FBG) levels (with an ideal target of <5.5 mmol/L [<100 mg/dL] to achieve glycosylated hemoglobin [HbA1c] <7%).

OBJECTIVE

This review investigated options for, and clinical efficacy of, titration algorithms of insulin glargine in type 2 diabetes.

METHODS

Articles from peer-reviewed journals were identified through searches of MEDLINE (years: 2000-2006). Search terms included insulin glargine, titration, algorithm, and type 2 diabetes. Studies were assessed and included in this review if they provided information regarding the method of dose titration of insulin glargine used.

RESULTS

A total of 12 studies were identified and included in this review. In the 24-week Treat-to-Target study, in which 756 patients were randomized to receive either insulin glargine or neutral protamine Hagedorn (NPH) insulin, once-daily using a simple titration regimen (titration of daily insulin dose by 0-2, 2, 4, or 6-8 IU if mean fasting plasma glucose over the 3 previous days was >or=5.6-<6.7, >or=6.7-<7.8, >or=7.8-<10.0 or >or=10 mmol/L [>or=100-<120, >or=120-<140, >or=140-<180, or >or=180 mg/dL], respectively, in the absence of plasma glucose <4.0 mmol/L [<72 mg/dL]) more patients reached HbA1c <or=7% without nocturnal hypoglycemia with insulin glargine versus NPH insulin (33.2% vs 26.7%; P < 0.05). In the 24-week AT.LANTUS (A Trial comparing LANTUS Algorithms to achieve Normal blood glucose Targets in subjects with Uncontrolled blood Sugar) study, 4961 patients were randomized to receive insulin glargine with either clinic-managed (as in the Treat-to-Target study) or patient-managed dose titration (increase insulin dose by 2 IU every 3 days in the absence of blood glucose <4.0 mmol/L [<72 mg/dL]). Greater reductions in HbA(1c) were found with patient- versus clinic-managed titration (-1.22% vs -1.08%; P < 0.001), and fewer patients experienced hypoglycemia with clinic-managed titration (29.8% vs 33.3%; P < 0.01).

CONCLUSIONS

The results from the studies discussed in this review suggest that adequate titration of the insulin dose, either by physicians or by patients, can help patients reach treatment goals, including HbA(1c) <7% and FBG <5.5 mmol/L (<100 mg/dL). The choice between algorithms may depend on clinical circumstance and a patient's willingness and ability to become more involved in management of therapy.

Race, ethnicity, and use of thiazolidinediones among US adults with diabetes

OBJECTIVE

Significant race and ethnic disparities exist in diabetes-related health care. Using a nationally representative database, we sought to determine if use of thiazolidinediones (TZDs) differs by race and ethnicity. As a secondary objective, we sought to determine if race and ethnicity is associated with use of older oral antidiabetic agents, such as sulfonylureas and metformin.

RESEARCH DESIGN AND METHODS

Adult respondents to the 2003 Medical Expenditure Panel Survey with diabetes, identified by diagnosis code or self-report, were included. Race/ethnic groups were defined as: White/not-Hispanic; Black/not-Hispanic; Hispanic; or Other/not-Hispanic. Associations between use of oral antidiabetic agents (defined as > or = 1 prescription for a TZD, sulfonylurea, or metformin) and race/ethnicity, sex, age, insurance status, poverty status, and having a usual source of care were evaluated in univariate analyses with chi(2) tests and in adjusted analyses using logistic regression methods for survey data.

RESULTS

A total of 1873 US adults with diabetes were identified, with use of oral antidiabetic agents varying by drug class: 23.1% received TZDs, 45.3% received metformin, and 43.8% received sulfonylureas. Use of oral antidiabetic agents, by drug class, did not differ significantly by race/ethnicity (p = 0.33 for TZDs, p = 0.43 for metformin, p = 0.38 for sulfonylureas). In univariate analyses, only insurance status was significantly associated with use of TZDs (p = 0.03), and no variables were associated with use of sulfonylureas or metformin. In adjusted logistic regression analyses, there were no significant predictors of the use of TZDs or metformin, and only age was significantly associated with the use of sulfonylureas.

CONCLUSIONS

In a nationally representative database, fewer US adults with diabetes received TZDs compared with sulfonylureas or metformin in 2003. Although we were not able to differentiate between type 1 and type 2 diabetes, nor did we assess oral agent monotherapy versus combination therapy, we found that use of TZDs, sulfonylureas, and metformin did not differ based on race/ethnicity or other demographic variables such as sex, insurance status, poverty status, or having a usual source of health care.