Effects of exenatide versus sitagliptin on postprandial glucose,insulin and glucagon secretion,gastric emptying,and caloric intake: a randomized,cross-over study

ABSTRACT

Background: This study evaluated the effects of exenatide, a GLP-1 receptor agonist, and sitagliptin, a DPP-4 inhibitor, on 2-h postprandial glucose (PPG), insulin and glucagon secretion, gastric emptying, and caloric intake in T2D patients.

Methods: This double-blind, randomized cross-over, multi-center study was conducted in metformin-treated T2D patients: 54% female; BMI: 33?±?5?kg/m²; HbA_1c: 8.5?±?1.2%; 2-h PPG: 245?±?65?mg/dL. Patients received exenatide (5?µg BID for 1 week, then 10?µg BID for 1 week) or sitagliptin (100?mg QAM) for 2 weeks. After 2 weeks, patients crossed-over to the alternate therapy. Postprandial glycemic measures were assessed via standard meal test; caloric intake assessed by ad libitum dinner (subset of patients). Gastric emptying was assessed by acetaminophen absorption (Clinicaltrials.gov Registry Number: NCT00477581).

Results: After 2 weeks of therapy, 2-h PPG was lower with exenatide versus sitagliptin: 133?±?6?mg/dL versus 208?±?6?mg/dL, p?<?0.0001 (evaluable, N?=?61). Switching from exenatide to sitagliptin increased 2-h PPG by +73?±?11?mg/dL, while switching from sitagliptin to exenatide further reduced 2-h PPG by ?76?±?10?mg/dL. Postprandial glucose parameters (AUC, C_ave, C_max) were lower with exenatide than sitagliptin (p?<?0.0001). Reduction in fasting glucose was similar with exenatide and sitagliptin (?15?±?4?mg/dL vs. ?19?±?4?mg/dL, p?=?0.3234). Compared to sitagliptin, exenatide improved the insulinogenic index of insulin secretion (ratio exenatide to sitagliptin: 1.50?±?0.26, p?=?0.0239), reduced postprandial glucagon (AUC ratio exenatide to sitagliptin: 0.88?±?0.03, p?=?0.0011), reduced postprandial triglycerides (AUC ratio exenatide to sitagliptin: 0.90?±?0.04, p?=?0.0118), and slowed gastric emptying (acetaminophen AUC ratio exenatide to sitagliptin: 0.56?±?0.05, p?<?0.0001). Exenatide reduced total caloric intake compared to sitagliptin (?134?±?97?kcal vs. +130?±?97?kcal, p?=?0.0227, N?=?25). Common adverse events with both treatments were mild to moderate in intensity and gastrointestinal in nature.

Conclusions: Although this study was limited by a 2-week duration of exposure, these data demonstrate that, exenatide had: (i) a greater effect than sitagliptin to lower postprandial glucose and (ii) a more potent effect to increase insulin secretion and reduce postprandial glucagon secretion in T2D patients. In contrast to sitagliptin, exenatide slowed gastric emptying and reduced caloric intake. These key findings differentiate the therapeutic actions of the two incretin-based approaches, and may have meaningful clinical implications.     

Effect of pramlintide as an adjunct to basal insulin on markers of cardiovascular risk in patients with type 2 diabetes

ABSTRACT

Objective: Intensification of insulin therapy in patients with type 2 diabetes, while improving glycemic control, often leads to an increase in body weight and other markers of cardiovascular risk. The effects of pramlintide as an adjunct to basal insulin titration (without mealtime insulin) on glycemia and cardiovascular risk markers were examined.

Research design and methods: This was a post hoc analysis of a 16-week, double-blind, placebo-controlled study in patients with type 2 diabetes (N?=?211) using insulin glargine (without mealtime insulin)?±?oral agents. Patients were randomized to treatment with placebo or pramlintide (60 or 120?µg with major meals), and insulin glargine was titrated to target a fasting plasma glucose concentration of ≥70 to <100?mg/dL.

Main outcome measures: Endpoints included the change from baseline to Week 16 in body weight, high sensitivity C-reactive protein (hsCRP), triglycerides, HDL, LDL, and blood pressure.

Results: Pramlintide-treated patients lost weight and placebo-treated patients gained weight during 16 weeks of treatment (?1.6?±?0.3?kg vs. +0.7?±?0.3?kg, p?<?0.001; mean?±?SE). hsCRP was reduced in pramlintide-treated versus placebo-treated patients (?0.8?±?0.2?mg/L vs. 0.1?±?0.2?mg/L, p?<?0.01; mean?±?SE). Patients with baseline hsCRP?>?3?mg/L (high cardiovascular risk) demonstrated greater hsCRP reductions with pramlintide versus placebo treatment at Week 16 (p?<?0.05). Patients with baseline triglycerides ≥150?mg/dL or ≥200?mg/dL (high cardiovascular risk) showed significant reductions from baseline in triglyceride concentrations with pramlintide (?43?±?14?mg/dL or ?59?±?19?mg/dL; p?<?0.05; mean?±?SE) but not with placebo (1?±?29?mg/dLor ?3?±?54?mg/dL; mean?±?SE). No significant differences between pramlintide and placebo were observed for changes in HDL, LDL, or blood pressure. Pramlintide treatment was generally well tolerated. The most frequent adverse event related to pramlintide was mild-to-moderate nausea (31% pramlintide vs. 10% placebo). Pramlintide added to basal insulin did not increase the incidence of hypoglycemia. A limitation of the study was its relatively short duration.

Conclusions: Pramlintide, as an adjunct to basal insulin, was associated with improvements in several cardiovascular risk markers, warranting long-term clinical studies to determine its potential effects on cardiovascular risk.     

Patient characteristics,drug adherence patterns,and hypoglycemia costs for patients with type 2 diabetes mellitus newly initiated on exenatide or insulin glargine

ABSTRACT

Objective: Examine real-world effectiveness and hypoglycemia cost burden in patients with type?2 diabetes newly initiated on exenatide or insulin glargine.

Design and methods: Retrospective cohort study describing patient characteristics, drug adherence patterns, and 1-year hypoglycemia rates with associated costs using an administrative claims database. Adult subjects with type?2 diabetes had an initial claim for exenatide or insulin glargine between May?1, 2005 and June?30, 2007, and had continuous eligibility for ≥?6 months pre- and ≥?12 months post-initiation.

Results: The exenatide cohort (n?=?3262) was 53?±?10?years (±SD); 54% female. The insulin glargine cohort (n?=?3038) was 56?±?12?years; 41% female. The mean Deyo-Charlson comorbidity index score was 1.45 for exenatide versus 1.82 for insulin glargine (p?<?0.001). Baseline OAD use rates for exenatide and insulin glargine, respectively, were 77% versus 69% metformin; 47% versus 65% sulfonylurea; 50% versus 49% thiazolidinedione; 56% versus 60% multiple OAD. For patients with two or more pharmacy claims for exenatide or insulin glargine, the 12-month medication possession ratio (MPR) was 68?±?29% for exenatide and 58?±?28% for insulin glargine (p?<?0.001). MPR ≥?80% was higher for exenatide (p?<?0.001) and fewer patients discontinued therapy (p?<?0.001). The probability of a hypoglycemic event was significantly lower for exenatide (p?<?0.005), resulting in lower associated annual costs.

Conclusions: This study provides the first real-world observational comparison of type?2 diabetes patients newly initiated on exenatide or insulin glargine. Exenatide patients had a lower comorbidity burden, better drug adherence, and a lower rate of hypoglycemic events with associated costs. Retrospective database analyses examine medical care utilization in large populations using a relatively inexpensive and expedient approach. However, data are only representative of a commercial health-care plan with limited information on multiple variables usually collected during clinical trials.     

Once-daily insulin detemir in a cohort of insulin-naïve patients with type 2 diabetes: a sub-analysis from the PREDICTIVE study

ABSTRACT

Objective: PREDICTIVE^* is a large, observational study of the empirical use of insulin detemir in patients with type 1 or type 2 diabetes (T1DM/T2DM). This post hoc analysis evaluates insulin-naïve patients with T2DM uncontrolled on oral antidiabetic drugs (OADs) who were initiated and remained on once-daily insulin detemir for 12 weeks.

Research design and methods: This observational, multinational, multi-center, open-label prospective study evaluated the efficacy and safety of insulin detemir in 1653 insulin-naïve patients with T2DM (mean age 60.8?±?10.9 years, BMI 29.8?±?4.8?kg/m², and HbA_1C 8.82?±?1.50%). Statistical comparisons were made between baseline and 12-week follow up data. Our study was subject to the usual limitations of observational studies.

Main outcome measures: Endpoints were: incidence of serious adverse drug reactions, including number of hypoglycemic events (total, major, and nocturnal), glycemic parameters, and weight change.

Results: Following insulin initiation, no significant change occurred in the number of nocturnal hypoglycemic events or total hypoglycemic events (p?=?0.4513), and no serious adverse drug reactions were observed during the 12 weeks of treatment. HbA_1C decreased by a mean 1.25% (SD?±?1.25%; p?<?0.0001), with 30% of patients (n?=?383) achieving HbA_1C <7% at 12 weeks. Mean changes in fasting blood glucose and fasting blood glucose variability were –3.62?mmol/L (SD?±?2.93; p?<?0.0001) and ?0.48?mmol/L (SD?±?1.03; p?<?0.0001), respectively. Body weight decreased by a mean 0.5?kg (SD?±?3.3; p?<?0.0001), with weight loss or no weight change occurring in a substantial percentage of patients in each BMI category (<25, 25–30, 30–35, and >35?kg/m²). Patients with higher baseline BMI lost the most weight, with the greatest weight loss (–1.20?kg) reported in those with BMI >35?kg/m².

Conclusions: Empirical use of insulin detemir as an insulin initiation strategy can improve glycemic control with good tolerability, including a low risk of hypoglycemia and a weight benefit, in a majority of insulin-naïve patients uncontrolled on OADs.     

Effects of vildagliptin versus saxagliptin on daily acute glucose fluctuations in Chinese patients with T2DM inadequately controlled with a combination of metformin and sulfonylurea

Objective The present study aimed to compare the effects of the dipeptidyl peptidase-4 (DPP-4) inhibitors vildagliptin and saxagliptin on 24?hour acute glucose fluctuations in Chinese patients with type 2 diabetes mellitus (T2DM) inadequately controlled with a combination of metformin and sulfonylurea.

Research design and methods This was a 24 week, prospective, randomized, open-label, active-controlled study. Patients (N?=?73) with T2DM who had inadequate glycemic control (HbA1c 7.0%–10.0%) with a stable dosage of metformin plus gliclazide for more than 3 months were randomized to receive either vildagliptin 50?mg twice daily (BID, n?=?37) or saxagliptin 5?mg once daily (QD, n?=?36). Change in mean amplitude of glycemic excursions (MAGE) was assessed at the end of 24 weeks.

Results At baseline, the mean (±SD) age was 62.9?±?6.55 years, disease duration was 7.0?±?2.33 years, and HbA1c was 8.4?±?0.68%. After 24 weeks of treatment, the MAGE decreased from 5.81?±?1.16?mmol/L to 4.06?±?0.86?mmol/L (p<0.001) in the vildagliptin group and from 5.66?±?1.14?mmol/L to 4.79?±?1.25?mmol/L (p?=?0.003) in the saxagliptin group. The mean change in MAGE in the vildagliptin group was significantly greater than that in the saxagliptin group (1.74?±?0.48?mmol/L vs. 0.87?±?0.40?mmol/L, p<0.001). The mean change in HbA1c, from baseline to the study endpoint, in the vildagliptin and saxagliptin groups, was 1.22?±?0.40% and 1.07?±?0.36%, respectively, with no significant difference between the groups (p?=?0.091). The overall safety and tolerability of vildagliptin and saxagliptin were similar. The limitations of the study were a small number of patients and open-label administration of the study drug.

Conclusion Vildagliptin produced a significantly greater reduction in acute glucose fluctuations compared with saxagliptin when added to a dual combination of metformin and sulfonylurea in Chinese patients with T2DM.

Chinese clinical trial registration number ChiCTR-TRC-13003858.     

Recalculation of cardiovascular risk score as a surrogate marker of change in clinical care of diabetes patients: the Alphabet POEM project (Practice Of Evidence-based Medicine)

SUMMARY

Aims: To assess the impact of evidence-based strategies on the care of subjects with diabetes, in particular on their coronary heart disease (CHD) risk, using the Alphabet Strategy template and coronary heart disease (CHD) risk calculators as novel audit tools.

Methods: Diabetes and cardiovascular parameters were collected on 400 consecutive type 2 diabetes patients attending the outpatient clinic. The subjects were men and women aged 21-75 years with necessary follow-up data from referral or first chronological available letter in the notes (T0) to the most recent follow-up visit (Tfu). The average follow-up period was 5 years. Absolute CHD risk was calculated using the Framingham risk function and the United Kingdom Prospective Diabetes Study (UKPDS) risk engine. The results were analysed using Student's paired t-test and chi-squared test.

Results (T0 vs.Tfu): Advice: smoking status improved 18.3 vs. 15.5%: p?=?0.3. Blood pressure: systolic blood pressure improved 145.8?±?21.1 vs. 140.1?±?20.5mmHg: p?<?0.0001. Diastolic blood pressure improved 82.0?±?12.2 vs. 76.5?±?11.0mmHg: p?<?0.0001. Cholesterol: total cholesterol improved 5.8?±?1.6 vs. 4.9?±?1.0 mmol/L: p?<?0.0001; high density lipoprotein (HDL) cholesterol improved 1.05 vs. 1.26 mmol/L: p?<?0.001. Diabetes control: glycated haemoglobin (HbA1c)% worsened 7.9?±?1.8 vs. 8.1?±?1.5: p?<?0.0001. However, when adjusted for duration of diabetes, this improved non-significantly by 12% overall. Eye examination: improved 86.5 vs. 97.5%: p?<?0.001. Feet examination: improved 69.8 vs. 83.5%: p?<?0.001. Guardian drugs: significantly more patients were on aspirin (29.0 vs. 83.5%: p?<?0.001), angiotensin converting enzyme (ACE) inhibitors (32.0 vs. 64.5%: p?<?0.001), and lipid lowering therapy (16.8 vs. 55.0%: p?<?0.001). Heart disease risk scores: a significant reduction in Framingham 10-year absolute cardiac risk was achieved (20.6?±?10.04% vs. 16.7?±?9.1%: p?=?0.001). Using the UKPDS risk engine, there was a non-significant reduction in absolute CHD risk over the follow-up period (23.8?±?14.8% vs. 23.7?±?15.5: p?=?NS). There were significant improvements between age-adjusted risk score (Tadj) and follow-up values (Tfu) (Framingham: 23.67% (Tadj) vs. 16.7% (Tfu); UKPDS 31.2% (Tadj) vs. 23.7% (Tfu)). For UKPDS stroke risk, a significant improvement was seen from Tadj to Tfu (19.0% (Tadj) vs. 16.4% (Tfu): p?<?0.001), with a significant deterioration noted between T0 and Tfu (11.5% (T0) vs. 16.4% (Tfu): p?<?0.0001).

Conclusions:The Alphabet Strategy is a novel evidence-based approach to clinical diabetes care, which produced a statistically significant improvement in most of the assessed parameters. The Alphabet Practice Of Evidence-based Medicine (POEM) template is a useful clinical tool for diabetes care and audit. It includes most of the components of diabetes audit required by the National Service Framework (NSF) and the United Kingdom GP contract.     

Effect of saxagliptin monotherapy in treatment-naïve patients with type 2 diabetes

ABSTRACT

Objective: To evaluate the efficacy and safety of once-daily saxagliptin monotherapy in treatment-naïve patients with type 2 diabetes (T2D) and inadequate glycemic control.

Research design and methods: This study included a main treatment cohort (MTC) with 401 patients (HbA_1c?≥?7% and ≤10%) randomized and treated with oral saxagliptin 2.5, 5, or 10?mg once daily or placebo for 24 weeks and a separate open-label cohort (OLC) with 66 patients (HbA_1c?>?10% and ≤12%) who received saxagliptin 10?mg once daily for 24 weeks. Primary endpoint was HbA_1c change from baseline to week 24. Secondary endpoints included change from baseline to week 24?in fasting plasma glucose (FPG), proportion of patients achieving HbA_1c?<?7%, and changes in postprandial glucose area-under-the-curve (PPG-AUC). Efficacy analyses for continuous variables were performed using an ANCOVA model with last-observation-carried-forward methodology.

Results: In the MTC, saxagliptin demonstrated statistically significant decreases in adjusted mean HbA_1c changes from baseline (mean, 7.9%) to week 24 (?0.43%, ?0.46%, ?0.54%) for saxagliptin 2.5, 5, and 10?mg, respectively, vs. +0.19% for placebo (all p?<?0.0001). Adjusted mean FPG was significantly reduced from baseline (?15, ?9, ?17?mg/dL) for saxagliptin 2.5, 5, and 10?mg, respectively, vs. +6?mg/dL for placebo (p?=?0.0002, p?=?0.0074, p?<?0.0001, respectively). More saxagliptin-treated patients achieved HbA_1c?<?7% at week 24 (35% [p?=?NS], 38% [p?=?0.0443], 41% [p?=?0.0133]) for saxagliptin 2.5, 5, and 10?mg, respectively, than placebo (24%). PPG-AUC was reduced for saxagliptin 2.5, 5, and 10?mg (?6868, ?6896, ?8084?mg·min/dL, respectively) vs. placebo (?647?mg·min/dL) with statistical significance demonstrated for saxagliptin 5?mg (p?=?0.0002) and 10?mg (p?<?0.0001). HbA_1c, FPG, and PPG-AUC reductions were also observed in the OLC at 24 weeks. In the MTC, adverse event frequency was similar across all study arms. No cases of confirmed hypoglycemia (symptoms, with fingerstick glucose ≤50?mg/dL) were observed in either cohort. Saxagliptin was not associated with weight gain. Study limitations included the lack of a control group for the OLC and the use of prespecified rescue criteria, which limited the exposure time during which patients could remain on their originally randomized medication without the introduction of additional antihyperglycemic rescue treatment.

Conclusions: Once-daily saxagliptin monotherapy for 24 weeks was generally well tolerated and demonstrated clinically meaningful reductions in key parameters of glycemic control vs. placebo.

Trial Registration: Clinical Trials NCT00121641     

Efficacy and safety of exenatide administered before the two largest daily meals of Latin American patients with type 2 diabetes

ABSTRACT

Objective: To evaluate whether exenatide administered before breakfast and dinner (BD) or before lunch and dinner (LD) provided similar glycemic control in Latin American patients with type 2 diabetes mellitus (T2DM) who consume a small breakfast.

Methods: In this open-label, 2-arm study, patients taking metformin, sulfonylureas, and/or thiazolidinediones were randomized to exenatide before BD or before LD (5-μg exenatide for 4 weeks, then 10-μg exenatide for 8 weeks). Treatment assignment was determined by a computer-generated random sequence using an interactive response system. Patients were eligible for study inclusion if they consumed <15% of their total caloric intake at breakfast. The primary endpoint was HbA_1c change from baseline to endpoint. Secondary endpoints included fasting serum glucose (FSG) level, 7-point SMBG profile, and safety. Clinicaltrials.gov Identifier: NCT00359879.

Results: 377 participants (55% female, age 54 ± 10 years, weight 82 ± 15 kg, BMI 31 ± 4 kg/m2, HbA_1c 8.4 ± 0.9% mean ± SD) from Brazil and Mexico were randomized to study treatment. HbA_1c reduction with exenatide administration before BD was non-inferior to administration before LD (mean difference between (LD–BD) treatments: 0.14% 95% CI –0.04 to 0.32%,p = 0.120). Both treatments resulted in statistically significant HbA_1c reductions at endpoint (BD –1.2% and LD –1.1%, respectively, p < 0.001). In Brazil, the non-inferiority criteria were met for HbA_1c reduction between treatment arms (?0.12% CI ?0.37 to 0.13%, p = 0.344), whereas in Mexico, there was a difference favoring exenatide administration before BD (0.41% CI 0.16 to 0.66%, p = 0.002). At endpoint, there were no statistical significant differences between the BD and LD arms in mean change in FSG (0.50 mmol/L; CI ?0.02 to 1.02 mmol/L, p = 0.058) and daily mean change in SMBG (0.19 mmol/L; CI ?0.17 to 0.54 mmol/L, p = 0.295). The rates of symptomatic hypoglycemia (5.2 events/patient-year vs. 6.1 events/patient-year) and nausea (23% vs. 25%), were similar between the BD and LD arms, respectively. A limitation of the study design was that caloric intake of patients and meal times were not monitored.

Conclusions: In T2DM patients who consume a small breakfast, exenatide administration before breakfast or lunch resulted in significant improvement in glycemic control.     

Pioglitazone as monotherapy or in combination with sulfonylurea or metformin enhances insulin sensitivity (HOMA-S or QUICKI) in patients with type 2 diabetes

Background: Miyazaki etal, demonstrated using the hyperinsulinemic, euglycemic clamp that pioglitazone (PIO) enhanced insulin sensitivity in patients (n?=?23) with type 2 diabetes (T2D). Although considered the reference method for measuring insulin sensitivity, the clamp is seldom used in large clinical trials because of its complexity. The Homeostasis Model Assessment-Insulin Sensitivity (HOMA-S) and Quantitative Insulin Sensitivity Check Index (QUICKI) are two alternative insulin sensitivity surrogates that correlate with the clamp method and are suitable for use with large study populations.

Study aim: To evaluate the effect of PIO monotherapy and in combination therapy with sulfonylurea (SU) or metformin (MET) on insulin sensitivity as assessed by HOMA-S and QUICKI in a large group of patients (～1000).

Research design and methods: Patient data from three randomized, double blind, multicenter, parallel group, placebo-controlled registration trials (Studies-001 PIO monotherapy and 010 and 027 combination therapy with SU or MET, respectively) were analyzed for this study. We

evaluated insulin sensitivity for all three studies using HOMA-S and QUICKI.

Results: PIO 15, 30 and 45?mg enhanced HOMA-S compared with baseline (56.9-63.6%, p?=?0.0298); (53.7-64.7%, p?=?0.0008); (59.0-75.9%, p?<?0.0001), respectively. Only the 45?mg dose showed a difference from placebo (p?=?0.0025). Similarly, PIO enhanced QUICKI versus baseline (0.290-0.296, p?=?0.0026); (0.287-0.299, p?=?0.0001); (0.290-0.306, p?=?0.0001), respectively. Both the 30 and 45mg doses were different from placebo for QUICKI (p?=?0.0005, p?<?0.0001). PIO 15 and 30mg plus SU enhanced HOMA-S compared with baseline (58.4–.7%, p?=?0.0007; 53.2–68.4%, p?<?0.0001) and placebo plus SU (p?=?0.0129, p?<?0.0001, respectively). Likewise, PIO 15 and 30?mg plus SU enhanced QUICKI versus baseline (0.289-0.300, p?=?0.0001; 0.287-0.305, p?=?0.0001, respectively). Both doses had different effects from placebo plus SU (p?=?0.0001) for QUICKI. PIO 30mg combined with MET enhanced HOMA-S versus baseline (66.2–82.2%, p?<?0.0001) and placebo plus MET (p?=?0.0002).     

Effect of oral photochemotherapy (8-methoxypsoralen + UVA) on the electrophysiologic function of retina

Context: Since we had observed electroretinographic (ERG) abnormalities in some patients undergoing photochemotherapy with normal eye examination, we decided to investigate the effects of this therapy on retinal function.

Objective: To investigate the effects of oral photochemotherapy (8-methoxypsoralen?+?Ultraviolet-A) on electrophysiologic function of retina.

Materials and methods: Patients with vitiligo, psoriasis or eczema were enrolled. Patients with any abnormal eye exam or a positive drug or family history for retinal disease were excluded. Baseline standard ERG was provided with the RETIport32 device. The second ERG was performed 6 months after the first and at least 1 week after the last photochemotherapy session (mean number of sessions: 45?±?11). The outcome measures were changes in rod response, standard combined response, single-flash cone response, 30-Hz flicker (N1-P1) and oscillatory potentials amplitudes.

Results: Forty patients were enrolled; 20 of them (mean age: 31.1?±?12 years) completed the study. The mean rod response b-wave amplitude decreased from 88.9?±?47.5 to 86.4?±?36.6 and standard combined response b-wave amplitude decreased from 266.52 to 261.85?µV (p?=?0.422 and p?=?0.968, respectively) and the standard combined response a-wave amplitude increased from 155.4?±?40.0 at baseline to 165.1?±?48.4 in the follow-up ERG (p?=?0.092). The mean single-flash cone response a-wave amplitude decreased insignificantly in the follow-up ERG trace (34.5?±?13.7 and 29?±?15.4, respectively, p?=?0.242). The mean single-flash cone response b-wave amplitude showed an insignificant increase (p?=?0.087). The amplitudes of 30-Hz flicker wave and oscillatory potentials did not change significantly in the follow-up ERG (p?=?0.551 and p?=?0.739, respectively).

Conclusion: Since no significant change in ERG traces was observed, oral photochemotherapy seems safe for retinal electrophysiologic function.     

Comparative Haemodynamic Responses to the First Dose of Short- and Long-acting ACE Inhibitors in Patients with Congestive Heart Failure

Summary

Background: Angiotensin Converting Enzyme inhibitors (ACEi's) confer significant mortality and morbidity benefits in all functional grades of chronic heart failure (CHF). However, physicians' concerns regarding the possible occurrence of first-dose hypotension appear to be a contributing factor to their under-utilisation in both hospital and primary care settings. We investigated whether long-acting and short-acting ACEi's differ in their haemodynamic responses to the first-dose in patients with CHF.

Method: This was a multicentre, randomised, open, two-parallel-group study of captopril 6.25?mg and perindopril 2mg. 240 patients with CHF, age 68.9?±?8.9 years, of whom 66% were male, NYHAII—IV, with average blood pressure baseline values of 132.2?±?16.2/78.5?±?10.5mmHg for systolic and diastolic blood pressure, and left ventricular ejection fraction (LVEF) of 31.3?±?7.4% received either captopril (n?=?124) or perindopril (n?=?116). Blood pressure was continuously monitored during the 8?h following drug intake. Minimum levels and maximum decreases in systolic, diastolic and mean arterial pressures were measured, along with the incidence of hypotensive episodes defined as mean blood pressure (MBP) fall?>?20mmHg, whether symptomatic or not. Subgroups of patients distributed according to age, baseline blood pressure (BP) and LVEF were subsequently analysed.

Results: Overall, a statistically significant treatment effect in favour of perindopril was observed. First-dose hypotension was observed more frequently following captopril than perindopril administration, with lower MAP minimal levels (78.0?±?8.9 vs. 84.5?±?10.1?mmHg, p?<?0.0001), greater maximum falls (17.6?±?8.3 vs. 12.8?±?7.3mmHg, p?<?0.0001) and more frequent hypotensive episodes (42% vs. 15%, p?<?0.0001). The incidence of at least one symptomatic episode was also significantly higher with captopril (10 patients vs. one patient, p?=?0.029). Subgroup analyses according to age (< 70 years or > 70 years) or LVEF (< 30% or > 30%) reflected the main result.

Conclusion: Initiation of treatment with ACE inhibitors is associated with different haemodynamic and clinical tolerances in CHF patients, regardless of their risk for hypotension, with possible clinical implications.     

24-Week study on the use of collagen hydrolysate as a dietary supplement in athletes with activity-related joint pain

ABSTRACT

Background: Collagen hydrolysate is a nutritional supplement that has been shown to exert an anabolic effect on cartilage tissue. Its administration appears beneficial in patients with osteoarthritis.

Objective: To investigate the effect of collagen hydrolysate on activity-related joint pain in athletes who are physically active and have no evidence of joint disease.

Design and setting: A prospective, randomized, placebo-controlled, double-blind study was conducted at Penn State University in University Park, Pennsylvania. Parameters including joint pain, mobility, and inflammation were evaluated with the use of a visual analogue scale during a 24-week study phase.

Study participants: Between September 2005 and June 2006, 147 subjects who competed on a varsity team or a club sport were recruited. Data from 97 of 147 subjects could be statistically evaluated.

Intervention: One hundred and forty-seven subjects (72 male, 75 female) were randomly assigned to two groups: a group (n?=?73) receiving 25?mL of a liquid formulation that contained 10?g of collagen hydrolysate (CH-Alpha)^* and a group (n?=?74) receiving a placebo, which consisted of 25?mL of liquid that contained xanthan.

Main outcome measures: The primary efficacy parameter was the change in the visual analogue scales from baseline during the study phase in relation to the parameters referring to pain, mobility, and inflammation.

Results: When data from all subjects (n?=?97) were evaluated, six parameters showed statistically significant changes with the dietary supplement collagen hydrolysate (CH) compared with placebo: joint pain at rest, assessed by the physician (CH vs. placebo (–1.37?±?1.78 vs. –0.90?±?1.74 (?p?=?0.025)) and five parameters assessed by study participants: joint pain when walking (–1.11?±?1.98 vs. –0.46?±?1.63, p?=?0.007), joint pain when standing (–0.97?±?1.92 vs. –0.43?±?1.74, p?=?0.011), joint pain at rest (–0.81?±?1.77 vs. –0.39?±?1.56, p?=?0.039), joint pain when carrying objects (–1.45?±?2.11 vs. –0.83?±?1.71, p?=?0.014) and joint pain when lifting (–1.79?±?2.11 vs. –1.26?±?2.09, p?=?0.018). When a subgroup analysis of subjects with knee arthralgia (n?=?63) was performed, the difference between the effect of collagen hydrolysate vs. placebo was more pronounced. The parameter joint pain at rest, assessed by the physician, had a statistical significance level of p?=?0.001 (–1.67?±?1.89 vs. –0.86?±?1.77), while the other five parameters based on the participants’ assessments were also statistically significant: joint pain when walking (?p?=?0.003 (– 1.38?±?2.12 vs. – 0.54?±?1.65)), joint pain when standing (?p?=?0.015 (–1.17?±?2.06 vs. –0.50?±?1.68)), joint pain at rest with (?p?=?0.021 (–1.01 ±1.92 vs. –0.47?±?1.63)), joint pain when running a straight line (?p?=?0.027 (–1.50?±?1.97 vs. –0.80?±?1.66)) and joint pain when changing direction (?p?=?0.026 (–1.87?±?2.18 vs. –1.20?±?2.10)).

Conclusion: This was the first clinical trial of 24-weeks duration to show improvement of joint pain in athletes who were treated with the dietary supplement collagen hydrolysate. The results of this study have implications for the use of collagen hydrolysate to support joint health and possibly reduce the risk of joint deterioration in a high-risk group. Despite the study's size and limitations, the results suggest that athletes consuming collagen hydrolysate can reduce parameters (such as pain) that have a negative impact on athletic performance. Future studies are needed to support these findings.     

In vitro glucuronidation of aprepitant: a moderate inhibitor of UGT2B7

Abstract

1.?Aprepitant, an oral antiemetic, commonly used in the prevention of chemotherapy-induced nausea and vomiting, is primarily metabolized by CYP3A4. Aprepitant glucuronidation has yet to be evaluated in humans. The contribution of human UDP-glucuronosyltransferase (UGT) isoforms to the metabolism of aprepitant was investigated by performing kinetic studies, inhibition studies and correlation analyses. In addition, aprepitant was evaluated as an inhibitor of UGTs.

2.?Glucuronidation of aprepitant was catalyzed by UGT1A4 (82%), UGT1A3 (12%) and UGT1A8 (6%) and K_ms were 161.6?±?15.6, 69.4?±?1.9 and 197.1?±?28.2?µM, respectively. Aprepitant glucuronidation was significantly correlated with both UGT1A4 substrates anastrazole and imipramine (r_s?=?0.77, p?<?0.0001 for both substrates; n?=?44), and with the UGT1A3 substrate thyroxine (r_s?=?0.58, p?<?0.0001; n?=?44).

3.?We found aprepitant to be a moderate inhibitor of UGT2B7 with a K_i of ～10?µM for 4-MU, morphine and zidovudine. Our results suggest that aprepitant can alter clearance of drugs primarily eliminated by UGT2B7. Given the likelihood for first-pass metabolism by intestinal UGT2B7, this is of particular concern for oral aprepitant co-administered with oral substrates of UGT2B7, such as zidovudine and morphine.     

The role of microalbuminuria and insulin resistance as significant risk factors for white matter lesions in Japanese type 2 diabetic patients

ABSTRACT

Objective: The presence of white matter lesions (WML) is an important prognostic factor for the development of stroke. Microalbuminuria, which is associated with diabetes, has been flagged as a novel predictor for cerebrovascular events. This preliminary study was therefore designed to test the hypothesis that the presence of WML correlates with microalbuminuria and insulin resistance in patients with type 2 diabetic mellitus (DM) not receiving insulin treatment.

Patients and methods: Based on brain magnetic resonance imaging (MRI) findings, 90 type 2 diabetic patients were divided into two groups: a WML-positive group (57?±?8 years, mean?±?SD, n?=?34) and a WML-negative group (57?±?6 years, n?=?56). The level of blood glucose was assessed by fasting plasma glucose (FPG), fasting immunoreactive insulin (F-IRI), homeostasis model assessment (HOMA) index, and hemoglobin A _1c (HbA1c).

Results: The body mass index was higher in the WML-positive group than in the WML-negative group (p?<?0.01). Plasma levels of triglycerides were higher while high-density lipoprotein cholesterol (HDL-C) was lower in the WML-positive group than in the WML-negative group (p?<?0.05 and p?<?0.0001, respectively). Fasting plasma glucose (p?<?0.005), insulin concentrations (p?<?0.0001), HOMA index (p?<?0.0001), and urinary albumin excretion (p?<?0.0001) levels were higher in the WML-positive group than in the WML-negative group. Multivariate logistic analysis revealed that WML was independently predicted by the microalbuminuria and insulin resistance (p?<?0.005, p?<?0.0005, respectively).

Conclusion: The results of this preliminary study indicate that the presence of WML was associated with the microalbuminuria and insulin resistance in these Japanese patients with type 2 DM; larger cohort studies are warranted to confirm these findings.     

Effect of topiramate on choroidal thickness and anterior chamber parameters in the treatment of patients with migraine

Objective: To investigate the effects of topiramate on choroidal thickness and anterior chamber parameters using optical coherence tomography in the treatment of patients with migraine.

Methods: A total of 22 eyes of 22 adults (12 females, 10 males) diagnosed with migraine and scheduled to topiramate treatment for pain control were recruited in this prospective study. Choroidal thickness (CT), anterior chamber depth (ACD), anterior chamber angle (ACA), spherical refractive equivalent (SphEq) and intraocular pressure (IOP) measurements were recorded at baseline (prior the topiramate therapy), first and second month visits for the statistical analysis. One-way ANOVA with repeated measures test was used for the statistical evaluation.

Results: Mean age of the patients was 40.2?±?6.5?years. Mean CT at central fovea was 324?±?47?μm initially, 341?±?45?μm in the first month and 344?±?46?μm in the second month, thus first and second month measures were significantly higher than base values (p?p?=?0.001). Baseline ACD (3.66?±?0.22?mm) measures significantly decreased at the first month (3.63?±?0.22?mm) and second month (3.62?±?0.22?mm, p?=?0.009). Also, a significant reduction was detected in the first (36.2?±?4.9°) and second month (35.9?±?5.1°) ACA measures comparing with baseline (39.1?±?5.1°, p?=?0.05). A significant myopic shift was determined in the first and second month SphEq values (?0.08?±?0.6, ?0.10?±?0.6, respectively, p?=?0.05).

Conclusions: The study revealed increased CT and altered anterior chamber parameters and IOP due to topiramate therapy. Therefore, the patients using topiramate should be carefully monitored by an ophthalmologist considering the possible side effects.     

Effects of calcitriol on bone mineral density in patients treated with esomeprazole

Context: Proton pump inhibitor (PPI) increases the risk of decrease in bone mineral density (BMD). However, whether calcitrol improves this situation is unknown.

Objective: The current study investigates the effects of calcitriol on BMD in patients with esomeprazole therapy.

Materials and methods: Three hundred and eighty-six participants with gastrointestinal ulcerations were enrolled and randomly assigned into controlled and supplemented groups. Participants in the controlled group were prescribed esomeprazole (20?mg/qd), while the supplemented group was prescribed esomeprazole (20?mg/qd) and calcitriol (2.5?μg/qd). BMD, serum levels of calcium, carboxy-terminal collagen crosslinks (CTX), and alkaline-phosphatase (ALP) were assessed.

Results: (1) No significant between-group difference of age, gender, smoking, previous glucocorticoid use and hemoglobin level was found; (2) after 10.6?±?0.8?d of PPI therapy, BMD T score in the controlled group was slightly increased compared with initial (?1.25?±?0.08 versus ?1.28?±?0.06, p?=?0.084), while there was no change in the supplemented group (?1.25?±?0.05 versus ?1.26?±?0.03, p?=?0.308); (3) during study termination, calcium level in the supplemented group was slightly higher than the controlled group (2.05?±?0.03?mmol/L versus 2.01?±?0.05?mmol/L, p?=?0.073), while no significant differences of CTX (366.57?±?43.71?pg/mL versus 373.15?±?50.23?pg/mL, p?=?0.036) and ALP were found among these two groups (50.47?±?9.32?U/L versus 52.23?±?10.45?U/L, p?=?0.075).

Conclusion: Patients with gastrointestinal ulcerations with esomeprazole therapy, calcitriol supplement showed no efficacy on BMD changes.     

Brimonidine purite 0.1% versus brinzolamide 1% as adjunctive therapy to latanoprost in patients with glaucoma or ocular hypertension

ABSTRACT

Objective: To evaluate the efficacy and tolerability of brimonidine purite 0.1% in comparison to brinzolamide 1% when used as adjunctive therapy to latanoprost 0.005% in patients with glaucoma or ocular hypertension.

Methods: Randomized, single-center, investigator-masked, parallel-group clinical study. Patients with IOP?≥?18?mmHg while on once-daily latanoprost were randomized to adjunctive treatment with brimonidine purite TID (n?=?20) or brinzolamide TID (n?=?20) for 3 months. Intraocular pressure (IOP) was measured at 8 a.m., 10 a.m., and 4 p.m. at latanoprost-treated baseline and after 1 and 3 months of latanoprost and adjunctive therapy. A patient questionnaire was administered to evaluate the tolerability of eye drop instillation.

Results: Baseline mean diurnal IOP (± standard deviation, mmHg) on latanoprost was comparable between groups (brimonidine purite: 19.6?±?2.94; brinzolamide: 19.8?±?3.25; p = 0.846). Mean diurnal IOP at Month 3 was 16.3?±?2.63?mmHg with brimonidine purite and 17.8?±?2.19?mmHg with brinzolamide (?p = 0.028). Adjunctive use of brimonidine purite provided greater IOP lowering than brinzolamide at 10 a.m. (?p < 0.001) and 4 p.m. (?p = 0.050) and equivalent IOP lowering to brinzolamide at 8 a.m. (?p = 0.716). Blurred vision at Month 1 and bitter taste at Months 1 and 3 were more common upon instillation of brinzolamide eye drops.

Conclusion: Brimonidine purite 0.1% provided significantly lower IOP compared with brinzolamide 1% when used as adjunctive therapy to latanoprost. Both adjunctive therapies were well tolerated. Limitations of this study include the use of a single site and the sample size. Additional studies are needed to further evaluate these drugs as adjunctive therapy to prostaglandin analogs.     

A comparison of teriparatide and calcitonin therapy in postmenopausal Asian women with osteoporosis: a 6‐month study

ABSTRACT

Objective: The number of hip fractures is expected to double in the next 20 years, with current estimates that Asia will account for 37% of these cases. As bone mineral density (BMD) may be used as a measure of fracture risk, we sought to compare the effects of teriparatide with salmon calcitonin treatment on changes in BMD, biochemical bone markers, and safety in postmenopausal Asian women with osteoporosis.

Methodology: A total of 104 patients (?n = 47 teriparatide [20?µg/day subcutaneously] and n = 57 calcitonin [100?IU/day subcutaneously]) were enrolled in Hong Kong, Singapore, Philippines, Malaysia, and Thailand. Calcium (≥ 500?mg/day) and vitamin D (200–400?IU/day) supplements were taken throughout the 6‐month controlled, randomized study.

Results: Teriparatide was associated with a 5.03 ± 4.77% increase in lumbar spine BMD (?p < 0.0001, mean ± SD change from baseline), whereas changes in lumbar spine BMD for patients on calcitonin were not statistically significant (mean change of 0.36 ± 4.12%, p = 0.16). Comparison of the two groups indicated that teriparatide treatment improved lumbar spine BMD statistically significantly more than calcitonin (?p < 0.0001). No statistically significant changes were observed for total hip or femoral neck BMD. Serum bone-specific alkaline phosphatase (BSAP) increased by 55.9% (median change from baseline, p < 0.0001) in the teriparatide group, and remained stable with calcitonin (5.0% change, p = 0.24); osteocalcin increased by 156.15% (median change from baseline, p < 0.0001) with teriparatide, and decreased with calcitonin (–15.25%, p = 0.03). Similar rates of adverse events were observed, with nausea and dizziness the most commonly reported for both groups (teriparatide versus calcitonin, 13.0% versus 23.2% p = 0.21, 10.9% versus 21.4% p = 0.19, respectively). There were no clinically relevant changes observed in laboratory parameters.

Conclusions: Both treatments were similarly tolerated, however teriparatide was associated with greater increases in lumbar spine BMD and bone formation markers, demonstrating the unique mechanism of action and safety of this treatment for osteoporosis in these Asian women.     

Reduced central corneal thickness in patients with isotretinoin treatment

Context: It is well known that oral isotretinoin treatment causes numerous ocular side-effects.

Objective: To investigate the effect of systemic isotretinoin treatment on central corneal thickness (CCT) values due to meibomian gland disease (MGD).

Participants: In this prospective study, 47 patients (27 men, 20 women) with nodulocystic acne vulgaris treated with oral isotretinoin (0.8?mg/kg daily) were included.

Methods: All patients were analyzed with the Pentacam Scheimpflug topography at baseline, on the 3rd and 6th month of treatment. Main outcome measures were MGD scores and CCT.

Results: The mean age of patients was 25.1?±?4.4 years. The mean MGD scores were significantly higher at 3rd month (1.3?±?0.9) and 6th month (1.5?±?1.0) of treatment compared with baseline (1.1?±?0.9) (p?p?p?=?0.038, r?=??0.221).

Conclusion: Isotretinoin treatment causes higher MGD scores. A statistically significant decrease in CCT due to MGD was detected at 6th month of treatment.