Trajectory of glycated haemoglobin over time, using real-world data, in type 2 diabetes patients with obesity on a U-100 basal-bolus insulin regimen

AIMS

To identify patient clusters with poor glucose control among type 2 diabetes mellitus (T2DM) patients with obesity who are receiving basal-bolus insulin and to identify the potential therapeutic inertia factors associated with poor control.

METHODS

Glycated haemoglobin (HbA1c) trajectories across a 3-year period were structured at 6-month intervals for a retrospective cohort of T2DM patients with obesity on basal-bolus insulin from the Veterans' Health Administration database. Based on each patient's longitudinal HbA1c features, an unsupervised clustering procedure was used to determine the numbers of clusters and associated trajectory patterns. Multinomial logistic regression was used to examine the association between HbA1c trajectory clusters and patient characteristics/treatment patterns.

RESULTS

A total of 51 273 patients were included, of whom 11.2% were in a subgroup with persistent missingness of HbA1c values. For those with sufficient HbA1c observations, cluster analysis indicated six distinct HbA1c trajectories: stable low (35.8%); stable high (20.8%); descending low (10.5%); ascending low (10.2%); descending high (5.7%); and ascending high (5.7%). Being of Black ethnicity, not initiating noninsulin antihyperglycaemic agents (sodium-glucose cotransporter-2 inhibitors, glucagon-like peptide-1 receptor agonists or thiazolidinediones) or concentrated insulin, low adherence (measured by proportion of days covered), and reduced insulin prescription refills were factors associated with poorer HbA1c clusters; similar factors were associated with persistent HbA1c missingness.

CONCLUSION

The present study found the potential for therapeutic inertia among a significant proportion of T2DM patients with obesity on basal-bolus insulin. Subgrouping T2DM patients based on HbA1c missingness and HbA1c trajectories can inform disease management strategies.

Treatment Patterns and Outcomes Before and After Humulin R U-500 Initiation Among US Patients with Type 2 Diabetes Previously Prescribed ≤ 200 Units/day of U-100 Insulin

INTRODUCTION

Humulin R U-500 (U-500R) utilization has increased in the past few years, raising concerns as U-500R is indicated only for patients requiring > 200 units of insulin. Thus, evidence of dispensed total daily dose (dTDD) > 200 units of prior U-100 insulin based on pharmacy claims is increasingly used as a criterion to determine appropriate switching to U-500R by payers. The study compared the treatment patterns and outcomes before and after U-500R initiation among patients who were identified with ≤ 200 units/day U-100 insulin fill in order to understand the appropriateness of switching.

METHODS

Patients with type 2 diabetes who initiated U-500R (index date = first fill) with ≤ 200 units/day pre-index dTDD and > 200 units/day post-index dTDD were identified in a Veterans Health Administration dataset between 1 January 2014 and 30 June 2017. Descriptive analysis was conducted on treatment patterns (dTDD, insulin dosage [units/kg], adherence, number of prescription fills) and clinical outcomes (HbA1c, symptomatic hypoglycemic events). Associations between U-500R exposure and outcomes were evaluated using mixed-effects models. Subgroups of U-500R syringe and KwikPen users were analyzed separately.

RESULTS

Among 1191 U-500R initiators identified in the study the mean dTDD increased from the pre- to post-index periods (147.2 vs 346.3; p < 0.0001). The mean HbA1c decreased from pre- to post-initiation (9.6% vs 8.6%; p < 0.0001), and symptomatic hypoglycemia events per patient per year increased (2.0 vs 3.3, p < 0.0001). Mixed-effects models confirmed the significance of the changes (p < 0.0001). Device subgroups followed similar trends.

CONCLUSIONS

U-500R initiation was associated with large dTDD increases, improved glycemic control, and modest increases in hypoglycemia events, suggesting U-500R initiation may have corrected previous treatment compliance issues. Imposing dTDDs > 200 units before switching to U-500R criterion could hurt the opportunities for patients who need a simplified regimen for better outcomes.

Treatment Patterns and Outcomes, Before and After Humulin R U-500 Initiation, Among High-Dose Type 2 Diabetes Mellitus Patients in the United States

OBJECTIVE

Severely insulin-resistant type 2 diabetes (T2D) patients face unique treatment challenges. Humulin R U-500 (U-500R) as insulin monotherapy with both basal/bolus properties addresses these challenges, although it remains understudied. This retrospective study compared real-world patient characteristics, treatment patterns, and outcomes before and after U-500R initiation.

METHODS

Adults with T2D on dispensed doses of >180 units/d U-500R monotherapy (index date=first fill) with ≥9-month continuous enrollment both pre- and post-index date and ≥180 units/d insulin pre-index were identified using Veterans Health Administration data (January 1, 2014-January 30, 2017). Overall group was further stratified into elderly and 201 to 300 units dispensed total daily dose (dTDD) subgroups. Syringe and KwikPen users were separately analyzed as subcohorts. Treatment patterns (dTDD), insulin dosage (units/kg), proportion of days covered (PDC) with insulins, and outcomes (HbA1c and hypoglycemic events) were descriptively evaluated, with regression models used to confirm associations between exposure and outcomes.

RESULTS

Among 951 U-500R initiators (overall group), mean dTDD (248.5 vs 392.1), percentage of patients with insulin dosage >2 units/kg (38.6% vs 88.1%), and mean PDC (73% vs 77%) significantly increased from the pre- to post-index periods (all P<.001). Changes in HbA1c (9.3% vs 8.5%; P<.0001) and hypoglycemia events per patient per year (2.1 vs 3.1, P<.0001) were statistically significant and confirmed by regression models (P<.0001). Subgroups (elderly, 492; 201 to 300 units, 148) and device subcohorts (syringe, 714; KwikPen, 244) showed similar trends.

CONCLUSION

U-500R initiation was associated with significantly improved treatment compliance patterns and glycemic control, with modest increase in hypoglycemia events.

Trajectory of Glycated Hemoglobin Over Time Among Obese Type 2 Diabetes Patients on U-100 Basal-Bolus Insulin Regimen Using Real-World Data

Introduction: There is a consistent increase in prevalence of obese type 2 diabetes (T2D) patients, many of whom require insulin treatment. As endogenous insulin secretion dwindles and progressively increasing body weight worsens insulin resistance, exogenous insulin doses can be quite high. This presents unique disease management challenges to patients, treating physicians, and the health systems. These challenges could lead to therapeutic inertia and result in poor glycemic control (continuous increase or persistently high glycated hemoglobin [A1c]). Therefore, examining the A1c trajectory over a significant period could detect the existence and magnitude of therapeutic inertia. Further segmenting the patients based on their A1c trajectory over time would help formulate management strategies with tailored interventions to targeted patient segments with signs of therapeutic inertia. Objective: To segment obese patients with T2D on U-100 basal-bolus regimen based on A1c trajectory over a 3-year period. Methods: Adults with ≥2 T2D claims who were on U-100 basal-bolus regimen and with body mass index ≥30 kg/m² or diagnosis codes for obesity during the identification period (APR2014-SEP2015) in the Veterans Health Administration database were included. The study period was OCT2013-SEP2018 and patients were required to have continuous enrollment for ≥6 months pre- and ≥3 years post-index periods. We captured the A1c pattern at 6-month intervals over a 3-year period. Only patients with A1c in at least 4 of the 6 time periods were included. A longitudinal unsupervised trajectory clustering method using the traj R package was implemented. Twenty-four features of A1c trajectory were examined followed by feature reduction using factor analysis. Based on the selected features, K-means clustering was used to identify patient segments based on the A1c trajectory. We extended the approach by repeating the same process as above among patient cluster with stable A1c trajectory to detect further A1c patterns. Results: A total of 45,520 patients were included. Four patient clusters were identified based on distinct patterns of A1c trajectory. The first cluster has descending A1c over time (N=8,325; 18.3%) while the second one has ascending A1c over time (N=8,123; 17.8%). Among patients with stable A1c trajectory, two more clusters were identified: stable high (N=10,654; 23.4%) with persistently high A1c around 9.0% and stable low (N=18,378; 40.4%) with persistently low A1c around 7.2%. Conclusions: By applying an unsupervised machine learning algorithm on A1c trajectory over time, this study identified over 40% of obese T2D patients on basal-bolus regimen belong to segments with poor A1c control during a three-year period, suggesting the significant existence of therapeutic inertia. Further research is planned to identify various forms of therapeutic inertia associated with these segments.

The Effect of Prestudy Insulin Therapy on Safety and Efficacy of Human Regular U-500 Insulin by Pump or Injection: A Posthoc Analysis

OBJECTIVE

We conducted a posthoc analysis of the VIVID study (Safety and Efficacy of Human Regular U-500 Insulin Administered by Continuous Subcutaneous Insulin Infusion Versus Multiple Daily Injections in Subjects With Type 2 Diabetes Mellitus: A Randomized, Open-Label, Parallel Clinical Trial), comparing 2 delivery methods of human regular U-500 insulin (U-500R), continuous subcutaneous insulin infusion (CSII) versus multiple daily injection (MDI), in type 2 diabetes requiring high insulin, to determine influence of prestudy insulin on glycemic outcomes.

METHODS

We compared A1C, total daily insulin dose (TDD), weight, and hypoglycemia by subgroups of prestudy insulin (prestudy U-500R vs non-U-500R) and treatment (CSII vs MDI).

RESULTS

At baseline, prestudy U-500R had higher TDD, higher body mass index, lower A1C and fasting plasma glucose, and higher rate of hypoglycemia compared to non-U-500R. Active titration of U-500R reduced A1C in both subgroups, with maximum benefit at 8 weeks. At 26 weeks, CSII provided the greatest reduction in A1C in both subgroups, with a greater reduction in non-U-500R. MDI provided an A1C reduction in both subgroups, with the greater reduction in non-U-500R. At 8 weeks, prestudy U-500R reached its lowest A1C; thereafter, A1C rebounded with MDI and remained stable with CSII. In non-U-500R, A1C continued to decrease to study end. In non-U-500R, hypoglycemia increased during active titration, but then decreased in the posttitration maintenance period. In both subgroups, TDD increased from baseline with MDI but not with CSII. Body weight increased in both subgroups but was greater in prestudy U-500R with CSII compared to MDI.

CONCLUSION

Regardless of previous insulin, people on high-dose insulin could lower A1C with U-500R, with additional benefit from CSII. These results may provide guidance for use of U-500R in clinical practice.

Concentrated insulins in current clinical practice

New concentrated insulins (exceeding 100 units/mL) and dedicated devices have recently become available, offering new treatment options for people with diabetes, for basal and prandial insulin supplementation. The concentrated insulin formulations range from 2-fold concentration (insulin lispro 200 units/mL) with rapid-acting prandial action to 5-fold concentration (human regular insulin, 500 units/mL) with basal and short-acting prandial actions. Long-acting basal insulins include degludec 200 units/mL and glargine 300 units/mL. Concentrated insulins have been developed with the goal of easing insulin therapy by reducing the volume and number of injections and in some cases making use of altered pharmacokinetic and pharmacodynamic properties. This review summarizes the unique characteristics of each concentrated insulin to help healthcare providers and people with diabetes understand how to best use them.

Patient-reported outcomes in transition from high-dose U-100 insulin to human regular U-500 insulin in severely insulin-resistant patients with type 2 diabetes: analysis of a randomized clinical trial

Background

Initiation and titration of human regular U-500 insulin (U-500R) with a dosing algorithm of either thrice daily (TID) or twice daily (BID) improved glycemic control with fewer injections in patients with type 2 diabetes treated with high-dose, high-volume U-100 insulin. The objective of this analysis was to compare patient-reported outcomes between U-500R TID and BID treatment groups in this titration-to-target randomized, clinical trial.

Methods

In this 24-week, open-label, parallel trial, 325 patients were randomized to TID (n = 162) or BID (n = 163) U-500R after a 4-week lead-in period (screening). The Treatment Related Impact Measure-Diabetes (TRIM-D) and EQ-5D-5L questionnaires were administered at screening, baseline/randomization, and endpoint (24 weeks). The Visual Analog Scale-Injection Site Pain (VAS-ISP) was assessed at baseline/randomization, 12 weeks, and endpoint.

Results

The TRIM-D showed statistically significant improvements in overall scores from baseline to endpoint for both BID and TID groups, most domains in the TID group, and all domains in the BID group. The BID group achieved better scores than the TID patients in overall and in treatment burden, daily life, and compliance domains (p < .05). EQ-5D-5L index scores showed no statistically significant differences for TID and BID groups (and no differences between TID and BID groups) from baseline to endpoint. VAS-ISP scores improved for both treatment groups (−5.60 TID; −6.47 BID; p < .05 for both) from baseline to endpoint.

Conclusions

U500 can be successfully titrated for improved glycemic control using BID and TID regimens with diabetes-specific Patient-Reported Outcomes showing improvements in both arms; however, BID had better scores than TID in overall, treatment burden, daily life, and compliance domains.

Trial registration

These secondary analyses are based on the study first received January 22, 2013 and reported in Clinical Trial Registry No.: NCT01774968.

Healthcare costs and adherence associated with human regular U-500 versus high-dose U-100 insulin in patients with diabetes

OBJECTIVE

Describe the characteristics, costs, and adherence of patients receiving human regular U-500 insulin (U-500R) compared with those of patients receiving high-dose (≥150 units/day) U-100 insulin.

METHODS

Data from Truven Health MarketScan Research Databases, July 1, 2008, through December 31, 2010, were used. The U-100 cohort received ≥150 units/day of U-100 insulin for ≥31 days during the first 60 days after the index date. The U-500R cohort received ≥2 prescriptions of U-500R after the index date. Analyses were performed on propensity-matched cohorts. The changes in annualized costs were compared between the 2 cohorts using paired t tests. Adherence was assessed by the proportion of days covered (PDC) and compared using a 2-sample t test. Glycemic efficacy data were not available in this database.

RESULTS

There were 1,044 U-500R-treated patients (19.1% with type 1 diabetes [T1D]) and 11,520 U-100-treated patients (23.8% with T1D) identified, from which 1,039 matched pairs were obtained. The mean decrease of $1,290 in annual pharmacy costs for the U-500R cohort was significantly different from the mean increase of $2,586 for the U-100 cohort (P<.001; 95% confidence interval, -$4,345 to -$3,422). More U-500R patients experienced hypoglycemia (17.3% vs. 11.8%; P<.001), but the hypoglycemia rate per person and related costs were not significantly different between cohorts. Finally, the mean 12-month PDC was 65.0% for U-500R versus 47.6% for U-100 patients (P<.0001).

CONCLUSION

Compared with treatment with ≥150 units/day of U-100 insulin, treatment with U-500R was associated with decreases in pharmacy costs, a higher percentage of patients experiencing hypoglycemia, and greater treatment adherence.

Initiation of human regular U-500 insulin use is associated with improved glycemic control: a real-world US cohort study

AIM

Describe the characteristics of patients initiating human regular U-500 insulin (U-500R) and their subsequent glycemic control in a real-world setting.

METHODS

US Humedica electronic health record system data (July 2007-September 2011) were used to identify patients with diabetes aged ≥18 years with ≥1 records for U-500R prescriptions, 6 months of preindex data, 12 months following first use of U-500R, and at least one glycated hemoglobin (HbA1c) value in both preindex and postindex periods. Paired t tests were used to measure the change in HbA1c from preindex to postindex periods (last or most recent values) and hypoglycemia.

RESULTS

Among patients initiating U-500R (N=445), 96.9% had type 2 diabetes with mean age 57 years and mean body mass index 40.4 kg/m(2). Postindex prescriptions were written for U-500R alone (47.0%, group A) and concomitant U-500R/U-100 insulins (53.0%, group B). Concomitant oral antihyperglycemic agents (AHAs) and non-insulin injectable AHAs were used by 43.4% and 14.6% of patients, respectively. Following initiation of U-500R, mean HbA1c improved 0.68% in all patients (p<0.0001 compared with baseline), but the decrease in HbA1c did not differ significantly between groups (A: 0.78%; B: 0.60%). Overall, hypoglycemic events, largely captured in the outpatient setting, increased in incidence from 6.7% to 11.9% (p≤0.0001) and from 0.23 to 0.39 events/patient/year, an increase of 0.16 (p=0.003), from preindex to postindex.

CONCLUSIONS

This real-world outcomes analysis demonstrates that U-500R initiation is associated with a clinically meaningful improvement in glycemic control over the subsequent 12-month period with modest increase in incidence and rate of hypoglycemia.

Cost, healthcare resource utilization, and adherence of individuals with diabetes using U-500 or U-100 insulin: a retrospective database analysis

OBJECTIVE

To describe costs, healthcare resource utilization, and adherence of US patients receiving human regular U-500 insulin (U-500R), compared to patients receiving high-dose (>200 units/day) U-100 insulins (U-100) by subcutaneous injection for the treatment of diabetes.

METHODS

A retrospective analysis of data from Thomson Reuters MarketScan Research Databases (7/1/2008 to 12/31/2010). Difference-in-differences analyses were conducted on cost (medical, pharmacy, and overall costs) and on healthcare resource utilization variables (overall, diabetes-related, and non-diabetes-related medical visits). Adherence rates to the index insulins were assessed by proportion of days covered (PDC).

RESULTS

Seven hundred and eleven (19%) patients in the U-500R cohort and 1508 (6%) patients in the U-100 cohort met selection criteria. Propensity score matching resulted in 684 matched pairs. Mean change in annualized pharmacy costs was in favor of the U-500R vs the U-100 cohort (-$1258 vs $3345, a difference of -$4603, p < 0.0001). Mean overall cost increase in the U-500R vs the U-100 cohort was also lower ($1999 vs $9104, a difference of -$7105, p = 0.005). The proportion of patients with at least one coded hypoglycemic event during the 12-month post-index period was higher in the U-500R vs the U-100 cohort (17.1% vs 11.7%, p < 0.005), but neither hypoglycemia rate (2.73 vs 2.90 events per person) nor hypoglycemia-specific costs (mean $1669 vs $1543) were significantly different. No significant differences were noted between cohorts for change (post-pre) in any resource utilization category. PDC was greater in the U-500R vs the U-100 cohort (65.2% vs 39.5%, p < 0.0001).

LIMITATIONS

Claims data are not as accurate as empirical evaluation by a clinician. Glycemic control data were not available for this analysis.

CONCLUSIONS

In patients requiring high-dose insulin, treatment with U-500R vs high-dose U-100 insulins is associated with significant decreases in pharmacy and overall costs, slightly higher hypoglycemia incidence, no difference in hypoglycemia-specific costs or in resource utilization, and better adherence.

Carbon sequestration and estimated carbon credit values as measured using 13C labelling and analysis by means of an optical breath test analyser

Recent developments in optical systems (isotope-selective non-dispersive infrared spectrometry) for breath testing have provided a robust, low-cost option for undertaking (13)C analysis. Although these systems were initially developed for breath testing for Helicobacter pylori, they have an enormous potential as a soil science research tool. The relatively low cost of the equipment, US$15,000-25,000, is within the research budgets of most institutes or universities. The simplicity of the mechanisms and optical nature mean that the equipment requires relatively low maintenance and minimal training. Thus methods were developed to prepare soil and plant materials for analysis using the breath test analyser. Results that compare conventional mass spectrometric methods with the breath test analyser will be presented. In combination with simple (13)C-plant-labeling techniques it is possible to devise methods for estimating carbon sequestration under different agronomic management practices within a short time frame. This enables assessment of the carbon credit value of a particular agronomic practice, which can in turn be used by policy makers for decision-making purposes. For global understanding of the effect of agricultural practices on the carbon cycle, data are required from a range of cropping systems and agro-ecological zones. The method and the approach described will enable collection of hard data within a reasonable time.

The effect of soil temperature and moisture on organic matter decomposition and plant growth

The effect of soil temperature and moisture on plant growth and mineralisation of organic residues was investigated using 15N-labelled soybean residues and temperature-controlled tanks in the glasshouse. Treatments were arranged in a factorial design with: three soil temperatures (20, 26 and 30 degrees C), two soil moisture regimes (8% (-800 Kpa) or 12% (-100 Kpa)), soybean residues added (enriched at 1.82 atom % 15N excess) or no residues; and either sown with ryegrass or not sown. Pots were sampled six weeks after planting and 15N-enrichment and delta13C of the plant and soil fractions were determined. Soil inorganic N was also periodically measured. Available inorganic N increased significantly with addition of residues and generally decreased with increasing temperature. Plant dry matter decreased significantly with increase in soil temperature and increased with increasing moisture. Root-to-shoot ratio declined with increased temperature and moisture. Percentage nitrogen derived from residues (%Ndfr) increased linearly with increased temperature and moisture. Delta13C decreased linearly with increasing temperature and decreasing moisture status. There was a significant correlation between transpiration and dry matter production, but there was no correlation between water use efficiency and delta13C. The results suggest that C: N ratio of the root material effects the root turnover and in turn the water supply capacity of the root system.