A Randomized Controlled Trial of Vildagliptin Versus Alogliptin: Effective Switch From Sitagliptin in Patients With Type 2 Diabetes

Background

We investigated the effects of vildagliptin or alogliptin on blood glucose and hemoglobin A1c (HbA1c) in patients with type 2 diabetes inadequately controlled by sitagliptin.

Methods

In a single-center open-label trial, 35 patients with inadequate glycemic control on sitagliptin therapy (50 mg once daily) were randomly switched to treatment with vildagliptin (50 mg twice daily) or alogliptin (25 mg once daily). After 12 weeks, patients who failed to achieve the target HbA1c level of < 7.0% with vildagliptin or alogliptin treatment were switched to high-dose sitagliptin (100 mg once daily) and the effect on glycemic control was assessed.

Results

Vildagliptin did not significantly alter the mean plasma glucose level (175.5 ± 54.4 mg/dL vs. 179.1 ± 73.4 mg/dL) or HbA1c (8.01% vs. 8.02%) after 12 weeks. With alogliptin, mean plasma glucose increased from 175.4 ± 50.9 mg/dL to 195.3 ± 55.0 mg/dL after 12 weeks and HbA1c increased significantly from 8.0% to 8.3% (P < 0.05). At 12 weeks after switching from vildagliptin to high-dose sitagliptin (100 mg daily), HbA1c was increased to 8.3%, but it was significantly (P < 0.05) reduced to the baseline level of 8.0% after switching from alogliptin. The reduction of HbA1c was significantly greater in the vildagliptin group than the alogliptin group (P = 0.008), but the response rate (achieving the target HbA1c < 7.0%) did not differ significantly between the two groups.

Conclusion

The glucose-lowering effects of these three dipeptidyl peptidase-4 (DPP-4) inhibitors (vildagliptin, alogliptin, and sitagliptin) were different, and the effects of vildagliptin and sitagliptin were stronger than that of alogliptin.

Clinicopathologic Impact of Early Medullary Ray Injury in Patients Following Kidney Transplantation

BACKGROUND

Previously, we explored the histopathologic characteristics of medullary ray injury (MRI) inducing interstitial fibrosis and tubular atrophy (IF/TA) to determine its etiologies, which include calcineurin inhibitor (CNI) toxicity and urologic complications. However, we did not examine the effects of these etiologies on long-term kidney allograft prognosis, because biopsy timing differed among cases.

AIM

We examined the influence of early MRI on kidney allograft prognosis using protocol biopsies taken within a 3-month time frame.

METHODS

We defined early MRI as tubular degeneration with interstitial edema or mild fibrosis localized to the medullary ray. We divided 53 protocol biopsies into 2 groups, with and without early MRI. Early MRI+ cases with isometric vacuolization were classified as CNI toxicity; those with Tamm-Horsfall protein in the interstitium and a thyroidlike appearance were classified as urinary tract system abnormalities; remaining cases were classified as "others." We compared changes in serum levels of creatinine (sCr) over 3 years and fibrosis extent at 1 year.

RESULTS

The sCr levels were significantly higher in the MRI+ group than the MRI- group at 3 years (P = .024). Examining the 3 MRI+ subgroups, only the MRI+ urinary tract system abnormalities group had significantly high sCr levels compared to the MRI- group (P = .019). The MRI+ group showed significant signs of IF/TA at 1 year.

CONCLUSIONS

Early MRI after kidney transplantation was significantly more likely to develop IF/TA at 1 year and had higher sCr levels at 3 years. In such cases, intervention might preserve graft function over the long term.

Potential utility of cinacalcet as a treatment for CDC73-related primary hyperparathyroidism: a case report

We report a Japanese pedigree with familial primary hyperparathyroidism due to a CDC73 mutation. To our knowledge, this is the first report of cinacalcet as a treatment for CDC73-related primary hyperparathyroidism. The proband had severe psychomotor retardation and received laryngotracheal separation surgery. At 19 yr of age, he developed acute pancreatitis. Hypercalcemia (12.2-13.8 mg/dL), elevated levels of intact PTH (86-160 pg/mL), and a tumor detected upon neck ultrasonography led to the diagnosis of primary hyperparathyroidism. Family history and biochemical examinations revealed that three family members (the proband's mother, elder brother, and maternal grandfather) had primary hyperparathyroidism. We identified a novel heterozygous mutation, c.240delT, p.Glu81Lysfs*28, in the CDC73 gene in three affected family members, excluding the proband's elder brother who refused genetic testing. Parathyroidectomy for the proband was considered as high-risk, because the tumor was located close to the tracheostomy orifice. After receiving approval from the institutional review board and obtaining the consent, we initiated cinacalcet treatment. At 22 yr of age, treatment with 100 mg of cinacalcet maintained serum calcium levels below 11.0 mg/dL with no apparent side effects. Our report presents the potential efficacy of cinacalcet as a treatment for CDC73-related primary hyperparathyroidism, in particularly inoperative cases.

Efficacy of switching from insulin glargine to insulin degludec in patients with type 1 diabetes: a 16-week retrospective study

We retrospectively investigated the effect of switching from insulin glargine (IGlar) to insulin degludec (IDeg) on glycemic control in Japanese patients with type 1 diabetes mellitus. We also evaluated the dose of IDeg, and assessed weight gain and the risk of hypoglycemia after switching. Forty-five patients with type 1 diabetes were switched from IGlar (once daily or twice daily) to IDeg (once daily) during routine medical care. Data were collected for 16 weeks after switching from IGlar to IDeg. The mean HbA1c (%) in weeks 4, 8, 12, and 16 was lower than it was in week 0 (8.0 ± 1.0, 8.0 ± 1.4, 7.9 ± 1.1, 7.6 ± 1.0 vs. 8.3 ± 1.3 %, p < 0.01). The total basal insulin dose (TBD) was significantly lower after 16 weeks of IDeg as compared to IGlar treatment (0.30 ± 0.12 vs. 0.24 ± 0.11 U/kg/day, p = 0.001). In the twice-daily IGlar group, TBD showed a significant decrease from 0.33 ± 0.12 to 0.26 ± 0.11 U/kg/day (p < 0.001) after switching to IDeg. In the once-daily IGlar group, TBD showed a slight but not significant decrease from 0.23 ± 0.08 to 0.20 ± 0.09 U/kg/day (p = 0.97). Hypoglycemic episodes were transiently increased, but the change was not significant. The blood glucose fluctuation was evaluated from self-monitoring data and the coefficient of variation (CV) was calculated. The CV showed only a minimal change from 48.3 ± 17.1 to 48.6 ± 14.2 % at 12 weeks after switching to IDeg (p = 0.73). In conclusion, once-daily IDeg improved glycemic control in patients with type 1 diabetes compared to the control achieved with IGlar, without increasing the risk of hypoglycemia. When switching from IGlar (especially twice daily), it is recommended that the initial dose of IDeg should be reduced in order to decrease the risk of hypoglycemia.

Effects of exenatide and liraglutide on 24-hour glucose fluctuations in type 2 diabetes

We evaluated the influence of short-term treatment with exenatide twice daily or liraglutide once daily on daily blood glucose fluctuations in 40 patients with type 2 diabetes inadequately controlled by sulfonylureas. The patients in a multicenter, open-label trial were randomly assigned to receive add-on exenatide (10 μg/day, n = 21) or add-on liraglutide (0.3-0.9 mg/day, n = 19), and underwent 24-hour continuous subcutaneous glucose monitoring. There was no significant between-group difference in glucose fluctuations during the day, as assessed by calculating mean amplitude of glycemic excursion (MAGE) and standard deviation (SD). However, the mean blood glucose levels at 3 hours after breakfast and dinner were significantly lower in the exenatide group than the liraglutide group (breakfast: 127.3 ± 24.1 vs. 153.4 ± 28.7 mg/dL; p = 0.006, dinner: 108.7 ± 17.3 vs. 141.9 ± 24.2 mg/dL; p < 0.001). In contrast, mean blood glucose levels and their SD were significantly lower between 0000 h and 0600 h in the liraglutide group than the exenatide group (average glucose: 126.9 ± 27.1 vs. 107.1 ± 24.0 mg/dL; p = 0.029, SD: 15.2 ± 10.5 vs. 8.7 ± 3.8; p = 0.020). Both groups had similar glucose fluctuations despite differences in 24-hour blood glucose profiles. Therefore, each of these agents may have advantages or disadvantages and should be selected according to the blood glucose profile of the patient.

Safety and tolerability of diazoxide in Japanese patients with hyperinsulinemic hypoglycemia

Diazoxide is a non-diuretic benzothiadiazine derivative, one of a group of substances introduced into clinical practice in the 1950s for the treatment of hypertension. Fajans reported the use of diazoxide for the treatment of insulinoma in 1979. Although patients with hyperinsulinemic hypoglycemia worldwide have been treated with diazoxide for more than 30 years, there are no recent reports about the adverse effects of this drug in Asian patients, including Japanese patients. Herein, we report the results of our retrospective clinical record review of 6 Japanese patients (3 females and 3 males, ranging in age from 58 to 91 years) with hyperinsulinemic hypoglycemia and inoperable insulinoma treated with diazoxide. Diazoxide improved control of hypoglycemic symptoms and maintained normoglycemia in 5 of the 6 patients, and was ineffective in one patient. Surprisingly, although all 6 patients received diazoxide according to the treatment strategy recommended in Western patients, 5 of the 6 patients developed edema and two developed congestive heart failure. Thus, when starting treatment with diazoxide in Japanese patients, the symptoms and signs of fluid retention should be evaluated carefully. Also, appropriate protocols for treatment with diazoxide should be evaluated by means of clinical trials in Japanese patients with hyperinsulinemic hypoglycemia.

Effect of sitagliptin on lipid profile in patients with type 2 diabetes mellitus

BACKGROUND

Animal studies have demonstrated that an inhibition of DPP-4 has an impact on the secretion of cholesterol and apoB by the small intestine. However, there is no consensus about the changes of the lipid profile following administration of sitagliptin.

METHODS

Accordingly, we treated patients who had type 2 diabetes complicated by dyslipidemia with sitagliptin and evaluated its effects on the profile of lipid parameters. A total of 248 outpatients with type 2 diabetes complicated by dyslipidemia were treated with sitagliptin at a daily dose of 50 mg. The levels and percent changes of lipid and glucose metabolism markers were measured at baseline and at 12 weeks after the initiation of treatment.

RESULTS

Both plasma glucose and HbA1c were significantly decreased. Among the lipid parameters, total cholesterol (TC) and non-high-density lipoprotein cholesterol (non-HDL-C) showed a significant decrease (TC 3.6±15.6%, non-HDL-C 2.9±19.7%; P < 0.05). Stratified analysis revealed a significant decrease of TC, low-density lipoprotein cholesterol (LDL-C) and non-HDL-C in the high triglyceride (TG) group (≥ 150 mg/dL) (P < 0.05). Analysis stratified by demographic factors demonstrated significant differences in the changes of TC, LDL-C and non-HDL-C. Multivariate analysis showed a significant decrease of the TC, LDL-C and non-HDL-C levels in the high TG group (≥ 150 mg/dL), as well as a significant decrease of TC and LDL-C in patients using strong statins.

CONCLUSIONS

The results suggested that sitagliptin caused a significant decrease of TC, LDL-C and non-HDL-C, particularly in patients with high baseline TG levels and those using strong statins.

Rapid growth of a thermotolerant yeast on palm oil

A thermotolerant and rapidly-growing yeast for production of single cell protein from palm oil was isolated and identified as Candida tropicalis F129. The optimum temperature and pH for growth were 38°C and 6.0, respectively. The yeast grew with a high specific growth rate, of 0.92/h in 2% (v/v) palm oil medium, compared with other oil-assimilating yeasts or hydrocarbon-utilizing thermophilic yeasts. The overall cell yield was 1.01 g dry cells/g palm oil after 12 h.

Colestimide improves glycemic control via hepatic glucose production in db/db mice

The objective of this study was to assess the chronic effects of a bile acid sequestrant, colestimide, on glucose metabolism. After db/db mice were fed a diet containing colestimide or cholic acid (CA) for 12 weeks, we investigated the impact of these agents on glucose and lipid metabolism. Colestimide significantly reduced the elevated fasting blood glucose level (p<0.01), and CA even more markedly reduced fasting blood glucose. The blood glucose level after an oral glucose load was significantly lower in the CA group than in the control group, but the colestimide group showed no significant difference. The insulin response to a glucose load was abolished in the control and colestimide groups. A hyperinsulinemic-euglycemic clamp study revealed that colestimide significantly improved the GIR (p=0.013). Hepatic EGP and Rd were also improved by colestimide, suggesting that it alleviated insulin resistance by suppressing hepatic glucose production and increasing peripheral glucose usage. CA significantly increased both the weight and cholesterol content of the liver, while colestimide reduced these parameters. Colestimide suppressed hepatic gene expression of SHP, but enhanced SREBP2 expression. On the other hand, CA increased the expression of SHP and lipogenic enzymes such as ACC and SCD-1, but had no effect on SREBP2. The present study demonstrated that colestimide improves hyperglycemia and hyperlipidemia, as well as reducing the hepatic lipid content. In contrast, CA exacerbates hyperlipidemia and increases the hepatic lipid content, although it improves glycemic control. Thus, colestimide is a well-balanced drug for the treatment of diabetes mellitus.

Second-line treatments for dyslipidemia in patients at risk of cardiovascular disease

Previous studies have shown that approximately 50% patients at risk of cardiovascular disease do not achieve lipid management goals. Thus, improvements dyslipidemia management are needed. We investigated the clinical choice and efficacy of second-line treatments for dyslipidemia in the Japanese clinical setting. Using a retrospective cohort design, we collected lipid profile data from patients who had been treated with hypolipidemic agents at a stable dosage for at least 12 weeks. These patients had then been administered a second-line treatment for dyslipidemia because they had not achieved the low-density lipoprotein cholesterol (LDL-C) management goals. We included data from 641 patients in our analysis. The top three choices for second-line treatment were adding ezetimibe, switching to strong statins (statin switching), and doubling the original statin dosage (statin doubling). Adding ezetimibe, statin switching, and statin doubling decreased LDL-C levels by 28.2 ± 14.5%, 23.2 ± 24.4%, and 23.5 ± 17.2%, respectively. Among these three strategies, adding ezetimibe decreased LDL-C levels to the maximum extent. In patients with dysglycemia, baseline-adjusted change in hemoglobin A1c (HbA1c) levels decreased slightly in the adding-ezetimibe, statin-switching, and statin-doubling groups, but the differences were not statistically significant among the groups (-0.10 ± 0.62%, -0.22 ± 0.54%, and -0.12 ± 0.52%, p = 0.19). In conclusion, the most common second-line treatment options for dyslipidemia were adding ezetimibe, statin switching, or statin doubling. Adding ezetimibe resulted in the highest reduction in LDL-C levels. These strategies did not increase HbA1c levels when administered with conventional diabetes treatment.

Increased active PTH(1-84) fraction as a predictor of poor mortality in male hemodialysis patients

We reported previously that serum parathyroid hormone [PTH(1-84)]/intact PTH[PTH(1-84) + PTH(7-84)] ratio provides the better marker for parathyroid function and bone turnover state than serum PTH level itself. The present study demonstrated that higher PTH(1-84)/intact PTH ratio, but not serum PTH(1-84) and intact PTH, predicted higher all-cause mortality in 177 male hemodialysis patients.

INTRODUCTION

We reported that PTH(1-84)/intact PTH ratio provides a clinically relevant marker for parathyroid function and the resultant bone turnover state. The purpose of our study was to investigate the association of PTH(1-84)/intact PTH ratio with all-cause mortality (ACM) in male hemodialysis patients.

METHODS

The study was performed for 70 months. Serum PTH in 177 male hemodialysis patients was measured with PTH(1-84)-specific whole PTH assay and intact PTH assay which cross-reacts with N-truncated PTH including PTH(7-84).

RESULTS

The patients (n = 177) were divided into higher and lower halves based on serum levels of PTH(1-84)/intact PTH ratio (cutoff value, 0.484), intact PTH (143.8 pg/mL), and PTH(1-84) (64.1 pg/mL). In Kaplan-Meier analysis, the higher group in whole PTH/intact PTH ratio had significantly higher ACM than the lower group (P = 0.020 by log-rank test), in contrast with the insignificant difference between the higher and lower groups in intact PTH and PTH(1-84). Multivariate Cox regression hazard analysis identified higher log [PTH(1-84)/intact PTH ratio], but not log intact PTH or log PTH(1-84) as a significant independent predictor [hazard ratio 14.428 (95% CI 2.486-83.728)] for ACM after adjustment for various factors including age, hemodialysis duration, presence/absence of diabetes mellitus, BMI, log C-reactive protein, serum albumin, calcium, and phosphate. The association existed between log [PTH(1-84)/intact PTH ratio] and ACM in those without vitamin D administration (n = 95).

CONCLUSION

Higher PTH(1-84)/intact PTH ratio, which provides a relevant marker for parathyroid function, may be a significant predictor of ACM in male hemodialysis patients.

Effect of Caloric Intake 25 or 30 kcal/kg/day on the Glycemic Control in Obese Patients With Type 2 Diabetes

Background

The recommended total dietary energy intake prescribed medical nutrition therapy for obese or overweight patients with type 2 diabetes in Japan is often set at 25 kcal/kg ideal body weight (IBW)/day. This study was conducted to determine the impact of the total dietary energy intake (25 or 30 kcal/kg IBW/day) on the glycemic control, lipid profile, and satisfaction level in overweight patients with type 2 diabetes.

Methods

We performed interview and a designed prospective, randomized, controlled, multicenter study trial. Recruitment for interview for doctors and hospitalization of the obese or overweight patients with type 2 diabetes began from September 2008 and continued until June 2010. The subjects were randomly assigned to 25 kcal/kg IBW/day group (25 kcal group) or 30 kcal/kg IBW/day group (30 kcal group). The primary endpoint was the body weight of the subjects at the time of hospitalization, at the time of discharge from the hospital, and at 3, 6 and 12 months after discharge from the hospital.

Results

The glycemic control, lipid control and body weight were similar between the 25 and 30 kcal groups during the 12-month follow-up, and the degree of satisfaction in respect of the medical treatment was significantly higher in the 30 kcal group than in the 25 kcal group at 1 year after discharge.

Conclusions

It is considered to be preferable for the caloric intake to be set at 30kcal/kg IBW/day rather than at 25 kcal/kg IBW/day for obese or overweight patients with type 2 diabetes.

Endovascular cannulation with a microneedle for central retinal vein occlusion

We developed a new surgical treatment in which a microneedle is used for retinal endovascular cannulation to treat eyes with central retinal vein occlusion by flushing thrombus out of the central retinal vein as it passes through the lamina cribrosa. The eyes of 12 consecutive patients (12 eyes) with central retinal vein occlusion were successfully treated using this novel treatment. At 24 weeks after surgery, 9 of 12 eyes had gained more than 15 letters in best-corrected visual acuity, and the mean decrease in central foveal thickness was 271.1 μm. Few complications were observed. The microneedle is stiff and sharp enough to facilitate retinal endovascular cannulation in eyes with central retinal vein occlusion. This new technique is a promising treatment of macular edema due to central retinal vein occlusion.