Recruitment to a clinical trial improves glycemic control in patients with diabetes

Gait-Adaptability Training in People With Hereditary Spastic Paraplegia: A Randomized Clinical Trial

BACKGROUND AND OBJECTIVES

In people with hereditary spastic paraplegia (HSP), reduced gait adaptability is common and disabling. Gait impairments result from lower extremity spasticity, muscle weakness, and impaired proprioception. The aim of this study was to assess the efficacy of a 5-week gait-adaptability training in people with pure HSP.

METHOD

We conducted a randomized clinical trial with a cross-over design for the control group, and a 15-week follow-up period after training. Thirty-six people with pure HSP were randomized to 5 weeks of (i) gait-adaptability training (10 hours of C-Mill training-a treadmill equipped with augmented reality) or (ii) a waiting-list control period followed by 5 weeks gait-adaptability training. Both groups continued to receive usual care. The primary outcome was the obstacle subtask of the Emory Functional Ambulation Profile. Secondary outcome measures consisted of clinical balance and gait assessments, fall rates, and spatiotemporal gait parameters assessed via 3D motion analysis.

RESULTS

The gait-adaptability training group (n = 18) did not significantly decrease the time required to perform the obstacle subtask compared to the waiting-list control group (n = 18) after adjusting for baseline differences (mean: -0.33 seconds, 95% CI: -1.3, 0.6). Similar, non-significant results were found for most secondary outcomes. After merging both groups (n = 36), the required time to perform the obstacle subtask significantly decreased by 1.3 seconds (95% CI: -2.1, -0.4) directly following 5 weeks of gait-adaptability training, and this effect was retained at the 15-week follow-up.

CONCLUSIONS

We found insufficient evidence to conclude that 5 weeks of gait-adaptability training leads to greater improvement of gait adaptability in people with pure HSP.

Diabetes management intervention studies: lessons learned from two studies

Introduction

Several clinical studies investigated improvements of patient outcomes due to diabetes management interventions. However, chronic disease management is intricate with complex multifactorial behavior patterns. Such studies thus have to be well designed in order to allocate all observed effects to the defined intervention and to exclude effects of other confounders as well as possible.

This article aims to provide challenges in interpreting diabetes management intervention studies and suggests approaches for optimizing study implementation and for avoiding pitfalls based on current experiences.

Main body

Lessons from the STeP and ProValue studies demonstrated the difficulty in medical device studies that rely on behavioral changes in intervention group patients. To successfully engage patients, priority should be given to health care professionals being engaged, operational support in technical issues being available, and adherence being assessed in detail.

Another difficulty is to avoid contamination of the control group with the intervention; therefore, strict allocation concealment should be maintained. However, randomization and blinding are not always possible. A limited effect size due to improvements regarding clinical endpoints in the control group is often caused by the Hawthorne effect. Improvements in the control group can also be caused with increased attention paid to the subjects. In order to reduce improvements in the control group, it is essential to identify the specific reasons and adjust study procedures accordingly. A pilot phase is indispensable for this. Another option is to include a third study arm to control for enhanced standard of care and study effects. Furthermore, retrospective data collection could be a feasible option. Adaptive study designs might reduce the necessity of a separate pilot study and combine the exploratory and confirmatory stages of an investigation in one single study.

Conclusion

There are several aspects to consider in medical device studies when using interventions that rely on changes in behavior to achieve an effective implementation and significant study results. Improvements in the control group may reduce effect sizes and limit statistical significance; therefore, alternatives to the traditional randomized controlled trials may be considered.

The Clinical Application of Mealtime Whey Protein for the Treatment of Postprandial Hyperglycaemia for People With Type 2 Diabetes: A Long Whey to Go

Mitigating postprandial hyperglycaemic excursions may be effective in not only enhancing glycaemic control for people with type 2 diabetes but also reducing the onset of diabetes-related complications. However, there are growing concerns over the long-term efficacy of anti-hyperglycaemic pharmacotherapies, which coupled with their rising financial costs, underlines the need for further non-pharmaceutical treatments to regulate postprandial glycaemic excursions. One promising strategy that acutely improves postprandial glycaemia for people with type 2 diabetes is through the provision of mealtime whey protein, owing to the slowing of gastric emptying and increased secretion of insulin and the incretin peptides. The magnitude of this effect appears greater when whey protein is consumed before, rather than with, a meal. Herein, this dietary tool may offer a simple and inexpensive strategy in the management of postprandial hyperglycaemia for people with type 2 diabetes. However, there are insufficient long-term studies that have investigated the use of mealtime whey protein as a treatment option for individuals with type 2 diabetes. The methodological approaches applied in acute studies and outcomes reported may also not portray what is achievable long-term in practice. Therefore, studies are needed to refine the application of this mealtime strategy to maximize its clinical potential to treat hyperglycaemia and to apply these long-term to address key components of successful diabetes care. This review discusses evidence surrounding the provision of mealtime whey protein to treat postprandial hyperglycaemia in individuals with type 2 diabetes and highlights areas to help facilitate its clinical application.

Optimization of Metformin in the GRADE Cohort: Effect on Glycemia and Body Weight

OBJECTIVE

We evaluated the effect of optimizing metformin dosing on glycemia and body weight in type 2 diabetes.

RESEARCH DESIGN AND METHODS

This was a prespecified analysis of 6,823 participants in the Glycemia Reduction Approaches in Diabetes: A Comparative Effectiveness Study (GRADE) taking metformin as the sole glucose-lowering drug who completed a 4- to 14-week (mean ± SD 7.9 ± 2.4) run-in in which metformin was adjusted to 2,000 mg/day or a maximally tolerated lower dose. Participants had type 2 diabetes for <10 years and an HbA1c ≥6.8% (51 mmol/mol) while taking ≥500 mg of metformin/day. Participants also received diet and exercise counseling. The primary outcome was the change in HbA1c during run-in.

RESULTS

Adjusted for duration of run-in, the mean ± SD change in HbA1c was -0.65 ± 0.02% (-7.1 ± 0.2 mmol/mol) when the dose was increased by ≥1,000 mg/day, -0.48 ± 0.02% (-5.2 ± 0.2 mmol/mol) when the dose was unchanged, and -0.23 ± 0.07% (-2.5 ± 0.8 mmol/mol) when the dose was decreased (n = 2,169, 3,548, and 192, respectively). Higher HbA1c at entry predicted greater reduction in HbA1c (P < 0.001) in univariate and multivariate analyses. Weight loss adjusted for duration of run-in averaged 0.91 ± 0.05 kg in participants who increased metformin by ≥1,000 mg/day (n = 1,894).

CONCLUSIONS

Optimizing metformin to 2,000 mg/day or a maximally tolerated lower dose combined with emphasis on medication adherence and lifestyle can improve glycemia in type 2 diabetes and HbA1c values ≥6.8% (51 mmol/mol). These findings may help guide efforts to optimize metformin therapy among persons with type 2 diabetes and suboptimal glycemic control.

Effectiveness of text message based, diabetes self management support programme (SMS4BG): two arm, parallel randomised controlled trial

OBJECTIVE

To determine the effectiveness of a theoretically based and individually tailored, text message based, diabetes self management support intervention (SMS4BG) in adults with poorly controlled diabetes.

DESIGN

Nine month, two arm, parallel randomised controlled trial.

SETTING

Primary and secondary healthcare services in New Zealand.

PARTICIPANTS

366 participants aged 16 years and over with poorly controlled type 1 or type 2 diabetes (HbA1c ≥65 mmol/mol or 8%) randomised between June 2015 and November 2016 (n=183 intervention, n=183 control).

INTERVENTIONS

The intervention group received a tailored package of text messages for up to nine months in addition to usual care. Text messages provided information, support, motivation, and reminders related to diabetes self management and lifestyle behaviours. The control group received usual care. Messages were delivered by a specifically designed automated content management system.

MAIN OUTCOME MEASURES

Primary outcome measure was change in glycaemic control (HbA1c) from baseline to nine months. Secondary outcomes included change in HbA1c at three and six months, and self efficacy, diabetes self care behaviours, diabetes distress, perceptions and beliefs about diabetes, health related quality of life, perceived support for diabetes management, and intervention engagement and satisfaction at nine months. Regression models adjusted for baseline outcome, health district category, diabetes type, and ethnicity.

RESULTS

The reduction in HbA1c at nine months was significantly greater in the intervention group (mean -8.85 mmol/mol (standard deviation 14.84)) than in the control group (-3.96 mmol/mol (17.02); adjusted mean difference -4.23 (95% confidence interval -7.30 to -1.15), P=0.007). Of 21 secondary outcomes, only four showed statistically significant improvements in favour of the intervention group at nine months. Significant improvements were seen for foot care behaviour (adjusted mean difference 0.85 (95% confidence interval 0.40 to 1.29), P<0.001), overall diabetes support (0.26 (0.03 to 0.50), P=0.03), health status on the EQ-5D visual analogue scale (4.38 (0.44 to 8.33), P=0.03), and perceptions of illness identity (-0.54 (-1.04 to -0.03), P=0.04). High levels of satisfaction with SMS4BG were found, with 161 (95%) of 169 participants reporting it to be useful, and 164 (97%) willing to recommend the programme to other people with diabetes.

CONCLUSION

A tailored, text message based, self management support programme resulted in modest improvements in glycaemic control in adults with poorly controlled diabetes. Although the clinical significance of these results is unclear, the findings support further investigation into the use of SMS4BG and other text message based support for this patient population.

TRIAL REGISTRATION

Australian New Zealand Clinical Trials Registry ACTRN12614001232628.

Melatonin Treatment Improves Insulin Resistance and Pigmentation in Obese Patients with Acanthosis Nigricans

OBJECTIVE

This study aimed to determine the effects of melatonin on insulin resistance in obese patients with acanthosis nigricans (AN).

METHODS

A total of 17 obese patients with acanthosis nigricans were recruited in a 12-week pilot open trial. Insulin sensitivity, glucose metabolism, inflammatory factors, and other biochemical parameters before and after the administration of melatonin were measured.

RESULTS

After 12 weeks of treatment with melatonin (3 mg/day), homeostasis model assessment insulin resistance index (HOMA-IR) (8.99 ± 5.10 versus 7.77 ± 5.21, p < 0.05) and fasting insulin (37.09 5 ± 20.26 μU/ml versus 32.10 ± 20.29 μU/ml, p < 0.05) were significantly decreased. Matsuda index (2.82 ± 1.54 versus 3.74 ± 2.02, p < 0.05) was significantly increased. There were also statistically significant declines in the AN scores of the neck and axilla, body weight, body mass index, body fat, visceral index, neck circumference, waist circumference, and inflammatory markers.

CONCLUSIONS

It was concluded that melatonin could improve cutaneous symptoms in obese patients with acanthosis nigricans by improving insulin sensitivity and inflammatory status. This trial is registered with ClinicalTrials.gov NCT02604095.

Adding Prandial Insulin to Basal Insulin Plus Oral Antidiabetic Drugs in Chinese Patients with Poorly Controlled Type 2 Diabetes Mellitus: An Open-Label, Single-Arm Study

INTRODUCTION

There is relatively little data from China on the efficacy and safety of adding prandial insulin to basal insulin plus oral antidiabetic drugs (OADs) in people with poorly controlled type 2 diabetes mellitus (T2DM). This study assessed the efficacy and safety of basal insulin dose optimization followed by the addition of prandial insulin in Chinese people with T2DM achieving suboptimal glycemic control with basal insulin and OADs.

METHODS

In this open-label, single-arm study, adults with T2DM receiving basal insulin plus OADs underwent insulin dose optimization for 12 weeks. At week 12, subjects who achieved fasting blood glucose (FBG) ≤6.5 mmol/L but not HbA1c ≤7% added one injection of prandial insulin at the main meal for an additional 24 weeks. Endpoints included mean HbA1c, the achievement rate of HbA1c ≤7%, hypoglycemia, and other adverse events (AEs).

RESULTS

A total of 120 subjects underwent basal insulin optimization; At week 12, 110 study subjects achieved FBG ≤6.5 mmol/L, of whom 66 did not achieve HbA1c ≤7% and therefore initiated prandial insulin. Three patients discontinued prandial insulin due to dissatisfaction with treatment outcome (n = 1), accidental injury (n = 1), or personal reasons (n = 1). After 24 weeks of basal-plus treatment, mean HbA1c significantly decreased (8.06% to 7.17%; p < 0.001), 65.1% of subjects achieved HbA1c ≤7%, there was no change in FBG (6.23-6.20 mmol/L; p = 0.118), and mean post-prandial blood glucose decreased (13.17-10.14 mmol/L; p < 0.001). During basal-plus treatment, three individuals experienced hypoglycemia, and no significant change in the mean subject weight was observed (73.2 vs. 73.3 kg; p = 0.379).

CONCLUSIONS

In people with T2DM who are achieving suboptimal glycemic control with basal insulin plus OADs, basal insulin dose optimization followed by the addition of prandial insulin improves glycemic control, is well tolerated, and is associated with a low incidence of hypoglycemia.

Should Studies of Diabetes Treatment Stratification Correct for Baseline HbA1c?

Aims

Baseline HbA1c is a major predictor of response to glucose lowering therapy and therefore a potential confounder in studies aiming to identify other predictors. However, baseline adjustment may introduce error if the association between baseline HbA1c and response is substantially due to measurement error and regression to the mean. We aimed to determine whether studies of predictors of response should adjust for baseline HbA1c.

Methods

We assessed the relationship between baseline HbA1c and glycaemic response in 257 participants treated with GLP-1R agonists and assessed whether it reflected measurement error and regression to the mean using duplicate ‘pre-baseline’ HbA1c measurements not included in the response variable. In this cohort and an additional 2659 participants treated with sulfonylureas we assessed the relationship between covariates associated with baseline HbA1c and treatment response with and without baseline adjustment, and with a bias correction using pre-baseline HbA1c to adjust for the effects of error in baseline HbA1c.

Results

Baseline HbA1c was a major predictor of response (R² = 0.19,β = -0.44,p<0.001).The association between pre-baseline and response was similar suggesting the greater response at higher baseline HbA1cs is not mainly due to measurement error and subsequent regression to the mean. In unadjusted analysis in both cohorts, factors associated with baseline HbA1c were associated with response, however these associations were weak or absent after adjustment for baseline HbA1c. Bias correction did not substantially alter associations.

Conclusions

Adjustment for the baseline HbA1c measurement is a simple and effective way to reduce bias in studies of predictors of response to glucose lowering therapy.

Improving the Quality of Outpatient Diabetes Care Using an Information Management System: Results From the Observational VISION Study

BACKGROUND

This study aimed to evaluate the effects of information management system (IMS) use with individuals with type 1 and type 2 diabetes who were treated in outpatient settings.

METHODS

In this 7-month, prospective, observational study, 965 adults with diabetes, mean (SD) baseline HbA1c 8.61(1.2)% (70.6[13.1] mmol/mol), were recruited from 132 outpatient care centers in Germany and Denmark. HbA1c was measured at baseline, month 4, and month 7. IMS reports were generated from uploaded self-monitored blood glucose data and therapy adjustments were documented at months 1 and 4. Hypoglycemic events were documented.

RESULTS

Mean (SD) HbA1c decreased from baseline in type 1 and type 2 diabetes patients at month 4 (-0.61[1.03]% (-6.7[11.3] mmol/mol), n = 213; -0.88[1.22]% (-9.6[13.3] mmol/mol), n = 589, respectively) and month 7 (-0.64[1.02]% (-7.0[11.1] mmol/mol), n = 219; -0.93[1.27]% (-10.2[13.9] mmol/mol), n = 594, respectively), all P < .0001, with no increase in hypoglycemic events. Therapy was adjusted in 106(42.7)% type 1 and 349(52.4)% type 2 diabetes patients at months 1 and 105(42.3)% type 1 and 282(42.3)% type 2 diabetes patients at month 4. Physicians used IMS reports to make therapy adjustments in 90% of patients at month 1 and 86% of patients at month 4.

CONCLUSIONS

Integration of the IMS into outpatient care facilitates significant improvements in glycemic control.

Care of diabetes in children and adolescents: controversies, changes, and consensus

Diabetes is one of the most common chronic medical disorders in children. The management of diabetes remains a substantial burden on children with diabetes and their families, despite improvements in treatment and rates of morbidity and mortality. Although most children with diabetes have type 1 diabetes, the increasing recognition of type 2 diabetes and genetic forms of diabetes in the paediatric population has important treatment implications. Diabetes therapy focuses strongly on targets for good metabolic control to reduce the risk of long-term complications. A parallel goal is to minimise short-term complications of hypoglycaemia and diabetic ketoacidosis. Technology offers opportunity for improvement in care, but has not yet fully lived up to its potential. New insights into the pathogenesis of diabetes and the development of new therapies have led to clinical trials aimed at the prevention of diabetes.

Identifying good responders to glucose lowering therapy in type 2 diabetes: implications for stratified medicine

Aims

Defining responders to glucose lowering therapy can be important for both clinical care and for the development of a stratified approach to diabetes management. Response is commonly defined by either HbA1c change after treatment or whether a target HbA1c is achieved. We aimed to determine the extent to which the individuals identified as responders and non-responders to glucose lowering therapy, and their characteristics, depend on the response definition chosen.

Methods

We prospectively studied 230 participants commencing GLP-1 agonist therapy. We assessed participant characteristics at baseline and repeated HbA1c after 3 months treatment. We defined responders (best quartile of response) based on HbA1c change or HbA1c achieved. We assessed the extent to which these methods identified the same individuals and how this affected the baseline characteristics associated with treatment response.

Results

Different definitions of response identified different participants. Only 39% of responders by one definition were also good responders by the other. Characteristics associated with good response depend on the response definition chosen: good response by HbA1c achieved was associated with low baseline HbA1c (p<0.001), high C-peptide (p<0.001) and shorter diabetes duration (p = 0.01) whereas response defined by HbA1c change was associated with high HbA1c (p<0.001) only. We describe a simple novel method of defining treatment response based on a combination of HbA1c change and HbA1c achieved that defines response groups with similar baseline glycaemia.

Conclusions

The outcome of studies aiming to identify predictors of treatment response to glucose lowering therapy may depend on how response is defined. Alternative definitions of response should be considered which minimise influence of baseline glycaemia.

Can integrated technology improve self-care behavior in youth with type 1 diabetes? A randomized crossover trial of automated pump function

Automated blood glucose (BG) and insulin pump systems allow wireless transmission of all BG readings to a user's pump. This study aimed to assess whether use of such a system, as compared with a manual BG entry insulin pump, resulted in higher mean daily frequency of BGs recorded after 6 months. A 12-month randomized crossover trial, comprising 2 phases, was conducted. All participants used insulin pump devices with automated vs manual BG entry for 6 months each; order of system use was randomly assigned. Device interactions were assessed from pump and glucometer downloads. Thirty-five participants were enrolled; 9 withdrew during the study. Use of the automated insulin pump system resulted in higher mean daily BG recorded over 6 months of use when compared to a manual BG entry system (5.8 ± 1.7 vs 5.0 ± 1.9; P = .02 [95% confidence interval, 0.14 to 1.58]). Bolus frequency was similar between groups. No HbA1c difference was observed between groups at 6 months (8.0% [64 mmol/l] ± 1.3 automated vs 7.7% [61 mmol/l] ± 0.9 manual; P = .38). Post hoc analysis demonstrated improved ΔHbA1c with automated system use in an adolescent subgroup with suboptimal baseline BG frequency (-0.9% vs + 0.5%; P = .003). Use of an automated glucometer/insulin pump resulted in higher number of BGs recorded over 6 months when compared to an insulin pump with manual BG entry. This may be especially beneficial for adolescent manual system users who enter <5 BGs per day into their pump.

Impact of renal denervation on 24-hour ambulatory blood pressure: results from SYMPLICITY HTN-3

BACKGROUND

Prior studies of catheter-based renal artery denervation have not systematically performed ambulatory blood pressure monitoring (ABPM) to assess the efficacy of the procedure.

OBJECTIVES

SYMPLICITY HTN-3 (Renal Denervation in Patients With Uncontrolled Hypertension) was a prospective, blinded, randomized, sham-controlled trial. The current analysis details the effect of renal denervation or a sham procedure on ABPM measurements 6 months post-randomization.

METHODS

Patients with resistant hypertension were randomized 2:1 to renal denervation or sham control. Patients were on a stable antihypertensive regimen including maximally tolerated doses of at least 3 drugs including a diuretic before randomization. The powered secondary efficacy endpoint was a change in mean 24-h ambulatory systolic blood pressure (SBP). Nondipper to dipper (nighttime blood pressure [BP] 10% to 20% lower than daytime BP) conversion was calculated at 6 months.

RESULTS

The 24-h ambulatory SBP changed -6.8 ± 15.1 mm Hg in the denervation group and -4.8 ± 17.3 mm Hg in the sham group: difference of -2.0 mm Hg (95% confidence interval [CI]: -5.0 to 1.1; p = 0.98 with a 2 mm Hg superiority margin). The daytime ambulatory SBP change difference between groups was -1.1 (95% CI: -4.3 to 2.2; p = 0.52). The nocturnal ambulatory SBP change difference between groups was -3.3 (95 CI: -6.7 to 0.1; p = 0.06). The percent of nondippers converted to dippers was 21.2% in the denervation group and 15.0% in the sham group (95% CI: -3.8% to 16.2%; p = 0.30). Change in 24-h heart rate was -1.4 ± 7.4 in the denervation group and -1.3 ± 7.3 in the sham group; (95% CI: -1.5 to 1.4; p = 0.94).

CONCLUSIONS

This trial did not demonstrate a benefit of renal artery denervation on reduction in ambulatory BP in either the 24-h or day and night periods compared with sham (Renal Denervation in Patients With Uncontrolled Hypertension [SYMPLICITY HTN-3]; NCT01418261).

A controlled trial of renal denervation for resistant hypertension

BACKGROUND

Prior unblinded studies have suggested that catheter-based renal-artery denervation reduces blood pressure in patients with resistant hypertension.

METHODS

We designed a prospective, single-blind, randomized, sham-controlled trial. Patients with severe resistant hypertension were randomly assigned in a 2:1 ratio to undergo renal denervation or a sham procedure. Before randomization, patients were receiving a stable antihypertensive regimen involving maximally tolerated doses of at least three drugs, including a diuretic. The primary efficacy end point was the change in office systolic blood pressure at 6 months; a secondary efficacy end point was the change in mean 24-hour ambulatory systolic blood pressure. The primary safety end point was a composite of death, end-stage renal disease, embolic events resulting in end-organ damage, renovascular complications, or hypertensive crisis at 1 month or new renal-artery stenosis of more than 70% at 6 months.

RESULTS

A total of 535 patients underwent randomization. The mean (±SD) change in systolic blood pressure at 6 months was -14.13±23.93 mm Hg in the denervation group as compared with -11.74±25.94 mm Hg in the sham-procedure group (P<0.001 for both comparisons of the change from baseline), for a difference of -2.39 mm Hg (95% confidence interval [CI], -6.89 to 2.12; P=0.26 for superiority with a margin of 5 mm Hg). The change in 24-hour ambulatory systolic blood pressure was -6.75±15.11 mm Hg in the denervation group and -4.79±17.25 mm Hg in the sham-procedure group, for a difference of -1.96 mm Hg (95% CI, -4.97 to 1.06; P=0.98 for superiority with a margin of 2 mm Hg). There were no significant differences in safety between the two groups.

CONCLUSIONS

This blinded trial did not show a significant reduction of systolic blood pressure in patients with resistant hypertension 6 months after renal-artery denervation as compared with a sham control. (Funded by Medtronic; SYMPLICITY HTN-3 ClinicalTrials.gov number, NCT01418261.).

A drug and disease model for lixisenatide, a GLP-1 receptor agonist in type 2 diabetes

Incretin hormone analogs such as glucagon-like peptide-1 (GLP-1) receptor agonists have emerged as promising new options for the treatment of type 2 diabetes mellitus (T2DM), targeting several of its pathophysiological traits, including reduced insulin sensitivity, inadequate insulin secretion, and loss of β-cell mass (BCM). This article describes the semi-mechanistic modeling of lixisenatide dose-response over time using fasting plasma glucose (FPG), fasting serum insulin (FSI) and glycated hemoglobin (HbA1c) data from two Phase II and four Phase III clinical trials, for a total of 2470 T2DM patients. Previously published models for FPG, FSI, and BCM as well as HbA1c were adapted and expanded to describe the available data. The model incorporated aspects describing disease progression, standard-of-care, FPG-dependent and -independent HbA1c synthesis, and covariate effects of body size, race, and sex. The final model described lixisenatide effects on β-cell responsiveness, insulin sensitivity and FPG-independent HbA1c synthesis, was able to describe the observed FPG, FSI, and HbA1c data accurately, and was successful in predicting data from an unseen Phase III clinical study.

Prevalence of diabetes treatment effect modifiers: the external validity of trials to older adults

BACKGROUND AND AIMS

Potential treatment effect modifiers (TEMs) are specific diseases or conditions with a well-described mechanism for treatment effect modification. The prevalence of TEMs in older adults with type 2 diabetes mellitus (DM) is unknown. Objectives were to 1) determine the prevalence of pre-specified potential TEMs; 2) demonstrate the potential impact of TEMs in the older adult population using a simulated trial; 3) identify TEM combinations associated with number of hospitalizations to test construct validity.

METHODS

Data are from the nationally-representative United States National Health and Examination Survey, 1999-2004: 8646 Civilian, non-institutionalized adults aged 45-64 or 65+ years, including 1443 with DM. TEMs were anemia, congestive heart failure, liver inflammation, polypharmacy, renal insufficiency, cognitive impairment, dizziness, frequent mental distress, mobility difficulty, and visual impairment. A trial was simulated to examine prevalence of potential TEM impact. The cross-sectional association between TEM patterns and number of hospitalizations was estimated to assess construct validity.

RESULTS

The prevalence of TEMs was substantial such that 19.0% (95% CI 14.8-23.2) of middle-aged adults and 38.0% (95% CI 33.4-42.5) of older adults had any two. A simulated trial with modest levels of interaction suggested the prevalence of TEMs could nullify treatment benefit in 3.9-27.2% of older adults with DM. Compared to having DM alone, hospitalization rate was increased by several combinations of TEMs with substantial prevalence.

CONCLUSIONS

We provide national benchmarks that can be used to evaluate TEM prevalence reported by clinical trials of DM, and correspondingly their external validity to older adults.

Resource utilisation and clinical data before and after switching between short-acting human insulin and rapid-acting insulin analogues in patients with type 2 diabetes: the SWING study

AIM

SWING was a prospective, observational study conducted in nine European countries primarily to assess direct treatment costs when switching from short-acting human insulins to rapid-acting insulin analogues (H-A) or vice versa (A-H) in patients with type 2 diabetes.

METHODS

Data were collected at a baseline visit (time of switch) and at approximately 3, 6 and 12 months post-switch.

RESULTS

In total, 2389 patients switched from H-A (n=2203) or A-H (n=186); another 603 were enrolled but ineligible. Mean (SD) direct diabetes-related costs (pro-rated to account for variable visit schedules) were €548.7 (865.8) 6 months prior to switch, €625.6 (1474.9) at 0-6 months and €568.6 (590.7) 6-12 months following switch for H-A, and €544.5 (421.0), €481.0 (301.5) and €461.6 (335.0) for A-H, respectively. Mean (SD) HbA(1c) decreased over 12 months by 1.08 (1.53)% units H-A and 1.17 (1.45)% units A-H. A small decline in hypoglycaemia occurred over time, but there were no clinically meaningful changes in mean PROs.

CONCLUSIONS

There were small changes in mean direct diabetes-related costs (following adjustment for time interval) in patients switching in either direction. Improvements in mean HbA(1c) and incidence of hypoglycaemia cannot necessarily be attributed to therapeutic switch.

The metabolic syndrome influences the response to incretin-based therapies

We hypothesize that type 2 diabetic patients with different phenotypes may show different response to incretin-based therapies. Therefore, we tested whether the presence of metabolic syndrome (MS) influences glycemic response to these drugs. We prospectively followed 211 patients, treated with the GLP-1 analog exenatide (n = 102) or a DPP-4 inhibitor (n = 109) for at least 4 months. Treatment was decided on clinical grounds. We collected baseline data (age, sex, BMI, waist, systolic and diastolic blood pressure, lipid profile, data on diabetic complications and concomitant treatment) and HbA1c at subsequent visits. Patients were divided into groups according to the presence/absence of MS. Compared to patients on exenatide, patients on DPP-4 inhibitors were older and had lower BMI, waist, diastolic blood pressure, fasting plasma glucose, and HbA1c. At means of baseline values, HbA1c reduction was similar in patients treated with exenatide or DPP-4 inhibitors. Patients on exenatide showed significantly higher HbA1c reduction if they had MS (-1.55 ± 0.22%; n = 88) than if they had not (-0.34 ± 0.18%; P = 0.002). Conversely, patients on DPP-4 inhibitors showed significantly lower HbA1c reduction if they had MS (-0.60 ± 0.12%; n = 73) than if they had not (-1.50 ± 0.24%; P < 0.001). Type of MS definition (ATP-III, IDF or WHO) poorly influenced these trends. The interaction between type of therapy (exenatide vs. DPP-4 inhibitors) and MS remained significant after adjusting for age, baseline HbA1c, BMI, and concomitant medications. In conclusion, the presence of MS appears to modify the response to incretin-based therapies. Given the non-randomized nature of this study, these data need to be replicated.

Relationship of baseline HbA1c, HbA1c change and HbA1c target of < 7% with insulin analogues in type 2 diabetes: a meta-analysis of randomised controlled trials

AIM

We performed a meta-analysis of randomised controlled trials (RCTs) with insulin analogues in type 2 diabetes utilising a least-squared regression model in order to assess the relationship between baseline HbA1c, the magnitude of HbA1c decrease and attainment of HbA1c target of < 7%.

METHODS

Randomised controlled trials involving insulin regimens (basal, prandial, biphasic and basal-bolus) were identified through electronic searches (MEDLINE, EMBASE, CINAHL and The Cochrane Library) through September 2010. We included any study arm of RCTs if they were at least 12 weeks in duration; the number of patients in any arm was more than 30 and reported the baseline HbA1c and change from baseline HbA1c.

RESULTS

We found 87 studies, with a total of 135 arms, and 38,803 patients. The weighted R(2) values for the overall analysis assessing the association between baseline HbA1c and absolute change in HbA1c or the proportion of patients at target were 0.485 (p < 0.001) and 0.146 (p < 0.001), respectively. Subanalyses of insulin regimens for the association between basal HbA1c and absolute decrease of HbA1c produced weighted R(2), which were significant for all insulin regimens with the highest association for basal-bolus (R(2) = 0.719, p < 0.001).

CONCLUSIONS

The strong positive relationship between baseline HbA1c and the magnitude of HbA1c change we found in RCTs using insulin analogues in type 2 diabetes should be considered when assessing the clinical efficacy of insulin therapies.

Treatment regimens with insulin analogues and haemoglobin A1c target of <7% in type 2 diabetes: a systematic review

We conducted a systematic review of randomized controlled trials that evaluated the effectiveness of insulin regimens (basal, biphasic, prandial, and basal-bolus) with insulin analogues to reach the haemoglobin A1c target of <7% in patients with type 2 diabetes. We identified 48 trials, with 85 arms and 30,588 patients. There were 38 arms using basal insulin, with 17,588 patients, and a primary outcome of 41.4% (95% CI=35.6-47.4%); 26 arms using biphasic insulin, with 9237 patients, and a primary outcome of 46.5% (40.8-52.3%); 9 arms using prandial insulin, with 1605 patients, and a primary outcome of 39.6% (95% CI, 28.6-51.3%); and 12 arms using basal-bolus insulin, with 2114 patients, and a primary outcome of 53.9% (43.5-64). The high heterogeneity was related, in part, to first time insulin use, final insulin dose, and use of oral drug. The overall incidence of hypoglycaemia ranged from 0 to 4.71 events/patient/30 days; weight gain ranged from 1.75 kg for basal to 3 kg for biphasic insulin. The HbA1c target of <7% can be achieved in a percentage of type 2 diabetic patients ranging from 40% to 54% depending on the particular insulin regimen.

Randomized trial of a literacy-sensitive, culturally tailored diabetes self-management intervention for low-income latinos: latinos en control

OBJECTIVE

To test whether a theory-based, literacy, and culturally tailored self-management intervention, Latinos en Control, improves glycemic control among low-income Latinos with type 2 diabetes.

RESEARCH DESIGN AND METHODS

A total of 252 patients recruited from community health centers were randomized to the Latinos en Control intervention or to usual care. The primarily group-based intervention consisted of 12 weekly and 8 monthly sessions and targeted knowledge, attitudes, and self-management behaviors. The primary outcome was HbA(1c). Secondary outcomes included diet, physical activity, blood glucose self-monitoring, diabetes knowledge and self-efficacy, and other physiological factors (e.g., lipids, blood pressure, and weight). Measures were collected at baseline and at 4- and 12-month follow-up. Change in outcomes over time between the groups and the association between HbA(1c) and possible mediators were estimated using mixed-effects models and an intention-to-treat approach.

RESULTS

A significant difference in HbA(1c) change between the groups was observed at 4 months (intervention -0.88 [-1.15 to -0.60] versus control -0.35 [-0.62 to 0.07], P < 0.01), although this difference decreased and lost statistical significance at 12 months (intervention -0.46 [-0.77 to -0.13] versus control -0.20 [-0.53 to 0.13], P = 0.293). The intervention resulted in significant change differences in diabetes knowledge at 12 months (P = 0.001), self-efficacy (P = 0.001), blood glucose self-monitoring (P = 0.02), and diet, including dietary quality (P = 0.01), kilocalories consumed (P < 0.001), percentage of fat (P = 0.003), and percentage of saturated fat (P = 0.04). These changes were in turn significantly associated with HbA(1c) change at 12 months.

CONCLUSIONS

Literacy-sensitive, culturally tailored interventions can improve diabetes control among low-income Latinos; however, strategies to sustain improvements are needed.

Improving glycaemic control in children and adolescents: which aspects of therapy really matter?

In paediatric diabetes, the concept of intensive therapy in the post-Diabetes Control and Complications Trial period has become subverted by a pharmaco-technological paradigm at the expense of other aspects of care such as goal-setting and psychosocial support. This review examines which patients benefit most from intensive therapy in terms of glycaemic control (HbA1c). It also reviews published controlled trial and observational data relating to the impact of various insulin types and delivery systems on glycaemic control and canvasses the literature dealing with the impact of patient support, philosophy of care, goal setting and treating team dynamic on HbA1c. Taking into account the characteristics of those patients who benefit most from intensive therapy, the quantum of HbA1c change and the persistence of changes that have been reported in selected and non-selected patient groups, it appears that there is a clear hierarchy in aspects of therapy that improve glycaemic control for children and adolescents with Type 1 diabetes. Prime issues appear to be patient support, team cohesion and goal setting. The reported glycaemic benefits achieved by an isolated emphasis upon a pharmaco-technological paradigm are limited in children and adolescents. It appears that only after the prime issues have been first considered will the potential benefits of the insulin types and regimens then be realized.

Contact frequency determines outcome of basal insulin initiation trials in type 2 diabetes

AIMS/HYPOTHESIS

The aim of the present study was to investigate whether predetermined contact frequency with the study team and endpoint insulin dose are associated with study outcomes in basal insulin initiation trials in type 2 diabetes.

METHODS

A systematic Medline search was performed. Using data from the selected studies, contact frequency was plotted against HbA(1c) reduction and endpoint insulin dose. The importance of face-to-face vs telephone contact was also analysed. Insulin dose was plotted against HbA(1c) reduction, hypoglycaemia rate and weight gain. To investigate non-specific study effects, the relationship between contact frequency and HbA(1c) was also assessed in dipeptidyl peptidase-4 (DPP-4) inhibitor trials.

RESULTS

The reduction in HbA(1c) was highly correlated with contact frequency and endpoint insulin dose (r (2) = 0.751, p < 0.001 and r (2) = 0.433, p = 0.008, respectively). However, after adjusting for contact frequency, the relationship between insulin dose and HbA(1c) reduction was no longer significant (p = 0.270). The frequency of both clinical and telephone contacts were independent predictors of HbA(1c) improvement (p = 0.010 and p < 0.001, respectively). We found no dose-response relationship between end-of-study insulin dose and hypoglycaemia or weight gain. In DPP-4 inhibitor studies, contact frequency was not positively associated with HbA(1c).

CONCLUSIONS/INTERPRETATION

The frequency of contact with the study team is highly correlated with the improvement in HbA(1c) achieved in basal insulin initiation trials in type 2 diabetic patients. This has important implications for trial design and interpretation, as well as for clinical care.

Use of a patient linked data warehouse to facilitate diabetes trial recruitment from primary care

Recruitment into clinical trials from primary care may be difficult. Our aim was to use the Secure Anonymised Information Linkage (SAIL) databank to identify potential participants for two factitious trials. We identified 284 and 711 participants for each study (population=250,086). This method appears promising in identifying trial participants.

Mobile diabetes intervention study: testing a personalized treatment/behavioral communication intervention for blood glucose control

BACKGROUND

National data find glycemic control is within target (A1c<7.0%) for 37% of patients with diabetes, and only 7% meet recommended glycemic, lipid, and blood pressure goals.

OBJECTIVES

To compare active interventions and usual care for glucose control in a randomized clinical trial (RCT) among persons with diabetes cared for by primary care physicians (PCPs) over the course of 1 year.

METHODS

Physician practices (n=36) in 4 geographic areas are randomly assigned to 1 of 4 study groups. The intervention is a diabetes communication system, using mobile phones and patient/physician portals to allow patient-specific treatment and communication. All physicians receive American Diabetes Association (ADA) Guidelines for diabetes care. Patients with poor diabetes control (A1c> or =7.5%) at baseline (n=260) are enrolled in study groups based on PCP randomization. All study patients receive blood glucose (BG) meters and a year's supply of testing materials. Patients in three treatment groups select one of two mobile phone models, receive one-year unlimited mobile phone data and service plan, register on the web-based individual patient portal and receive study treatment phone software based on study assignment. Control group patients receive usual care from their PCP. The primary outcome is mean change in A1c over a 12-month intervention period.

CONCLUSION

Traditional methods of disease management have not achieved adequate control for BG and other conditions important to persons with diabetes. Tools to improve communication between patients and PCPs may improve patient outcomes and be satisfactory to patients and physicians. This RCT is ongoing.

Introducing a simplified approach to insulin therapy in type 2 diabetes: a comparison of two single-dose regimens of insulin glulisine plus insulin glargine and oral antidiabetic drugs

AIM

To investigate whether the addition of a single bolus of insulin glulisine (glulisine), administered at either breakfast or main mealtime, in combination with basal insulin glargine (glargine) and oral antidiabetic drugs (OADs), provides equivalent glycaemic control in patients with type 2 diabetes, irrespective of the time of glulisine injection.

METHODS

A national, multicentre, randomized, open-label, parallel-group study of 393 patients with type 2 diabetes who were suboptimally controlled [haemoglobin A(1c) (HbA(1c)) > 6.5-9.0% and fasting blood glucose (BG) <or=6.7 mmol/l] on their previous glargine and OAD regimen. A single injection of glulisine was added, either at breakfast or at main mealtime, to their existing therapy.

RESULTS

The per-protocol group (n = 316) showed improved HbA(1c) (baseline vs. end-point) in the breakfast (7.4 vs. 7.0%; p < 0.0001) and main mealtime groups (7.3 vs. 6.9%; p < 0.0001). Glulisine given at breakfast was equally effective in controlling HbA(1c) as glulisine given at the main mealtime [adjusted HbA(1c) mean difference (95% confidence interval): 0.0481% (-0.115 to 0.211); p < 0.0001 for equivalence]. Overall, 30.7% of patients achieved HbA(1c)<or=6.5% at end-point but slightly more patients met this target in the main mealtime group vs. the breakfast group (33.8 vs. 27.8%; p = NS). This trend continued and was more marked when considering only those patients with HbA(1c) >7.0% at baseline and who reached HbA(1c)<or=7.0% at end-point (44.1% overall), with 52.2 and 36.5% for main mealtime and breakfast groups, respectively (p = 0.028). Most postprandial BG values improved within each group, while the number of hypoglycaemias was low and comparable between the two treatment groups.

CONCLUSIONS

A single bolus of glulisine, added to glargine and OADs, resulted in significantly improved HbA(1c) levels, irrespective of whether glulisine was administered at breakfast or at main mealtime. These results may represent a simplified and effective approach to treatment intensification in type 2 diabetes patients.

Efficacy and safety of Technosphere inhaled insulin compared with Technosphere powder placebo in insulin-naive type 2 diabetes suboptimally controlled with oral agents

OBJECTIVE

This double-blind, placebo-controlled, randomized, multicenter, parallel-group study compared the efficacy, safety, and tolerability of Technosphere insulin with Technosphere powder as placebo in insulin-naive type 2 diabetic patients whose diabetes was suboptimally controlled with oral antidiabetic agents.

RESEARCH DESIGN AND METHODS

Patients (n = 126) were randomly assigned to 12 weeks of therapy with Technosphere insulin or Technosphere powder after lifestyle education on nutrition, exercise, and instructions on inhaler use. The primary efficacy outcome was change in A1C from baseline to study end, and the secondary efficacy outcome was area under the curve for postprandial glucose levels during a meal test at treatment weeks 4, 8, and 12.

RESULTS

A1C reduction from a mean baseline of 7.9% was greater with Technosphere insulin than with Technosphere powder (-0.72 vs. -0.30%; P = 0.003). Postprandial glucose excursions were reduced by 56% with Technosphere insulin compared with baseline, and maximal postprandial glucose levels were reduced by 43% compared with Technosphere powder. Incidences of hypoglycemia, hyperglycemia, cough, and other adverse events were low in both groups. Body weight was unchanged in both groups.

CONCLUSIONS

Technosphere insulin was well tolerated and demonstrated significant improvement in glycemic control with clinically meaningful reductions in A1C levels and postprandial glucose concentrations after 12 weeks of treatment.