Hideo Machimura

Pleiotropic Effects of Sitagliptin in the Treatment of Type 2 Diabetes Mellitus Patients

Background Sitagliptin is a DPP-4 inhibitor that became available for use in Japan three years ago. This study was conducted to identify the pleiotropic effects of sitagliptin other than blood glucose lowering in Japanese type 2 diabetes mellitus patients. Methods A retrospective, observational study of 940 type 2 diabetes mellitus patients was conducted. The primary outcome measures were HbA1c, blood pressure, and lipid profiles measured at 0, 4, and 12 weeks of sitagliptin therapy. Results After 12 weeks of sitagliptin treatment, compared with baseline, HbA1c decreased 0.64% ± 0.86%; systolic blood pressure (SBP) and diastolic blood pressure (DBP) decreased significantly; and serum creatinine (Cr) and uric acid (UA) levels were mildly but significantly elevated. A correlation analysis of the changes in systolic blood pressure, diastolic blood pressure, creatinine, and uric acid (ΔSBP, ΔDBP, ΔCr, ΔUA) from baseline to 12 weeks showed significant negative correlations between ΔSBP and ΔCr, ΔSBP and ΔUA, and ΔDBP and ΔCr. Total cholesterol and postprandial triglycerides were significantly decreased at both 4 and 12 weeks. Alkaline phosphatase (ALP) decreased significantly, and there was a significant positive correlation between changes in ALP and HbA1c. Conclusions Sitagliptin seems to be effective not only in lowering blood glucose but also in lowering blood pressure, lipid, and ALP levels. Sitagliptin appears to contribute to a Na-diuretic action due to GLP-1.

Efficacy and safety of sitagliptin monotherapy and combination therapy in Japanese type 2 diabetes patients

(J Diabetes Invest, doi: 10.1111/j.2040‐1124.2012.00221.x, 2012)

Fibrinolysis in patients with diabetic nephropathy determined by plasmin-α2 plasmin inhibitor complexes in plasma

Activation of fibrinolysis in patients with diabetic nephropathy was determined by the plasma levels of plasmin-alpha 2 plasmin inhibitor complexes (alpha 2PIC) using a one-step sandwich enzyme immunoassay (EIA). Plasma levels of alpha 2PIC in diabetic patients with persistent proteinuria were significantly higher than those in diabetic patients without proteinuria, patients with chronic glomerulonephritis, and healthy adults. Plasma levels of alpha 2PIC in diabetic patients with intermittent proteinuria were also significantly higher than those of diabetic patients without proteinuria, patients with chronic glomerulonephritis, and healthy adults. Diabetic patients have been suggested to have a hypercoagulable state. The findings obtained from this study indicated that activation of fibrinolysis might counteract the hypercoagulable state in patients with diabetic nephropathy.

Safety and efficacy of adding sitagliptin to insulin in patients with type 2 diabetes: The ASSIST-K study

We retrospectively studied more than 1000 patients with type 2 diabetes attending 36 Japanese clinics to investigate the efficacy and safety of adding sitagliptin to various insulin regimens. We found that the treatment with add-on sitagliptin for 6-months was effective, irrespective of the type or dose of concomitant insulin.

Factors Influencing Changes in Hemoglobin A1c and Body Weight During Treatment of Type 2 Diabetes With Ipragliflozin: Interim Analysis of the ASSIGN-K Study

Background Ipragliflozin is a selective sodium glucose co-transporter 2 (SGLT2) inhibitor that blocks glucose reabsorption in the proximal tubules. SGLT2 inhibitors are expected to be effective in patients with insulin resistance and obesity, but it is important to select treatment according to patient background factors that minimizes the risk of adverse events. There have been a limited number of investigations into the relationship between the clinical efficacy (reducing hemoglobin A1c (HbA1c) and body weight (BW)) or safety of SGLT2 inhibitors and patient characteristics. Methods ASSIGN-K is an investigator-initiated, multicenter, prospective observational study examining the efficacy and safety of ipragliflozin (50 - 100 mg/day for 52 weeks) in Japanese patients with type 2 diabetes mellitus (T2DM) who had inadequate glycemic control with HbA1c ≥ 6.0% (National Glycohemoglobin Standardization Program) despite diet and exercise therapy or diet and exercise plus antidiabetic drug therapy. We conducted an interim analysis of the relationship between changes in HbA1c or BW and characteristics in patients who had been on treatment for more than 12 weeks. Results In 257 patients completing 12 weeks of treatment, HbA1c decreased significantly from 8.23% to 7.55% (-0.68%, P < 0.01). The change in HbA1c after 12 weeks was -0.17%, -0.33%, and -1.16% when baseline HbA1c was < 7%, 7% to < 8%, and ≥ 8%, respectively (P < 0.05, P < 0.01, and P < 0.01, respectively), and -1.30%, -0.62%, and -0.62% when baseline body mass index (BMI) was < 25, 25 to < 30, and ≥ 30, respectively (all P < 0.01). Stratified analysis showed that age, gender, or BMI did not have a significant influence on the improvement in HbA1c. Multiple regression analysis showed that reduction in HbA1c was greater as baseline HbA1c increased and the duration of diabetes decreased. A higher baseline HbA1c was associated with less weight loss. Conclusions Ipragliflozin significantly improved HbA1c in patients with T2DM. HbA1c improved more when baseline HbA1c was higher and the duration of diabetes was shorter, suggesting that current treatment policies for diabetes could be re-examined.

Is a Switch From Insulin Therapy to Liraglutide Possible in Japanese Type 2 Diabetes Mellitus Patients

Background To evaluate the efficacy of switching from insulin to the GLP-1 receptor agonist liraglutide in type 2 diabetes mellitus patients. Methods The subjects were 231 outpatients with type 2 diabetes mellitus being treated with liraglutide for the first time. For 161 patients, liraglutide was continued for 24 weeks (continuation group), and for 70 patients, liraglutide was discontinued before 24 weeks (discontinuation group). Fasting and postprandial blood glucose levels, HbA1c, body weight, and insulin dose were evaluated before the switch to liraglutide (baseline) and at 12 and 24 weeks of administration. Trends in HbA1c and weight were compared at 12 and 24 weeks of administration. Multiple regression analyses were conducted to identify clinical factors predicting a successful switch to liraglutide. Results Multiple regression analysis with ΔHbA1c as the dependent variable in the continuation group indicated that HbA1c at 12 weeks of administration decreased with higher baseline HbA1c and increased with higher baseline daily insulin doses. Multiple regression analysis with Δweight as the dependent variable indicated that Δweight at 24 weeks of liraglutide administration was higher with higher baseline daily insulin doses and longer duration of diabetes. Based on the area under the receiver operating characteristic curve, cut-off values of 19 units for daily insulin dose and nine years for duration of diabetes were identified. Conclusions Switching from insulin to liraglutide therapy is possible for carefully selected patients. Daily insulin dosage and duration of insulin therapy appear to be clinically useful indicators for the efficacy of liraglutide therapy.

Efficacy and Safety of Alogliptin in Patients With Type 2 Diabetes: Analysis of the ATTAK-J Study

Background Dipeptidyl peptidase-4 (DPP-4) inhibitors have been shown to reduce hemoglobin A1c (HbA1c) in patients with type 2 diabetes, but the reduction varies between patients and adequate glycemic control may not be achieved. We evaluated the efficacy and safety of the DPP-4 inhibitor alogliptin in the real clinical setting, and analyzed factors associated with the improvement of HbA1c by alogliptin treatment. Methods A retrospective observational study was performed in patients with type 2 diabetes attending hospitals or clinics belonging to the Kanagawa Physicians Association who received treatment with alogliptin for 1 year or longer. Patients using insulin were excluded from the study. The efficacy endpoints were HbA1c (National Glycohemoglobin Standardization Program value), blood glucose (fasting/postprandial), body weight, blood pressure (systolic/diastolic), liver function (glutamate oxaloacetate transaminase, glutamate pyruvate transaminase, and γ-glutamyl transpeptidase), kidney function (serum creatinine and estimated glomerular filtration rate), serum lipids (total cholesterol, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, and triglycerides), and serum amylase. Adverse events were compiled to assess safety. Results Of 330 patients whose case records were collected, 27 patients were excluded for protocol violations, leaving 303 patients to form the full analysis set. Compared with baseline, HbA1c showed a decrease by 0.54±1.22% (mean ± standard deviation) after 12 months of alogliptin treatment. Factor analysis demonstrated that the change of HbA1c after 12 months was significantly influenced by the baseline HbA1c level, duration of diabetes, concomitant use of sulfonylureas, and compliance with diet therapy. In addition, there was a significant reduction of total cholesterol, low-density lipoprotein cholesterol, and the estimated glomerular filtration rate after 12 months of alogliptin treatment, as well as a significant increase in serum creatinine. No significant changes of body weight, blood pressure, or liver function were observed. Symptoms of hypoglycemia occurred in two patients (0.6%). Conclusions Alogliptin displayed a significant hypoglycemic effect and excellent safety in routine clinical use. Factors influencing the change of HbA1c with alogliptin therapy may include the HbA1c at the start of treatment, the duration of diabetes, use of sulfonylureas, and compliance with diet therapy.

Factors Predicting Therapeutic Efficacy of Combination Treatment With Sitagliptin and Insulin in Type 2 Diabetic Patients: The ASSIST-K Study.

Background It is unclear whether dipeptidyl peptidase-4 inhibitors decrease hemoglobin A1c (HbA1c) in a glucose-dependent manner in patients on insulin therapy who have impaired insulin secretion. This study investigated factors influencing the efficacy of sitagliptin when used concomitantly with insulin to treat type 2 diabetes mellitus (T2DM) in the real-world setting. Methods A retrospective study was conducted of 1,004 T2DM patients at 36 Japanese clinics associated with the Diabetes Task Force of the Kanagawa Physicians Association. Eligible patients had been on insulin for at least 6 months, with a baseline HbA1c of 7.0% (53 mmol/mol) or higher. Baseline characteristics and laboratory data from 495 patients were subjected to multiple regression analysis to identify factors influencing the change of HbA1c. Results Most patients (n = 809) received sitagliptin at a dose of 50 mg. In the 1,004 patients, HbA1c decreased by 0.74% (6 mmol/mol) and body weight increased by 0.1 kg after 6 months of combination therapy. Multiple regression analysis showed that a higher baseline HbA1c, older age, and lower body mass index influenced the change of HbA1c after 6 months. Hypoglycemic symptoms occurred in 7.4%, but none were severe. Conclusions These results emphasize the importance of a higher HbA1c at the commencement of sitagliptin therapy in patients on insulin. Glucose-dependent suppression of glucagon secretion by sitagliptin may be useful in patients with impaired insulin secretion. Sitagliptin can be used concomitantly with insulin irrespective of the insulin regimen, duration of insulin treatment, and concomitant medications.

Cross-sectional survey of diabetic neuropathy in Kanagawa and clinical significance of a touch test using tissue paper.

Aims/Introduction:  The prevalence of diabetes mellitus is increasing rapidly in Japan, and diabetic neuropathy is a major factor decreasing diabetic patients’ quality of life, as well as a risk factor for sudden death. The present study aimed to determine the prevalence of diabetic neuropathy and raise awareness about it among patients and their physicians.

Effect of urokinase on preservation of renal function in patients with diabetic nephropathy

Long-term effects of urokinase on the preservation of renal function in patients with diabetic nephropathy were evaluated. Twenty-nine adult patients with non-insulin-dependent diabetes mellitus and overt proteinuria were randomly divided into two groups. One group was treated with daily oral administration of dipyridamole or dilazep dihydrochloride and weekly intravenous administration of urokinase; the other group was treated with dipyridamole alone. There was a significant decrease in the amount of proteinuria in the first group after 3 months of the treatment compared with the second group. There was also a significant preservation of renal function in the first group after three years of treatment compared with the second group. It was concluded that continuous administration of urokinase in addition to antiplatelet agents is useful in the treatment of patients with diabetic nephropathy.