Real-world outcomes of initiating insulin glargine-based treatment versus premixed analog insulins among US patients with type 2 diabetes failing oral antidiabetic drugs

Abstract

BackgroundIn patients with type 2 diabetes mellitus, basal-bolus strategies can improve treatment by offering dosing flexibility, and improved satisfaction, adherence, and clinical outcomes. The purpose of this study was to compare real-world outcomes between US patients initiating analog insulin therapy with insulin glargine and those initiating with a premixed analog insulin (PMX).MethodsThis was a retrospective study of data from patients (≥18 years) with type 2 diabetes mellitus in the IMPACT® database who initiated insulin treatment with insulin glargine (GLA) or a PMX. Clinical and economic outcomes were measured over one year, including persistence and adherence, consumption of insulin, glycemic outcomes, incident hypoglycemia, and health care resource utilization and cost.ResultsData from 2,502 patients were included in the analyses (n = 834 for PMX, n = 1,668 for GLA). Compared with PMX, persistence was higher and consumption of insulin was lower for GLA (both P < 0.0001). Adherence, glycemic outcomes, and hypoglycemia-related events were similar between groups, as were health care utilization and total health care costs. Diabetes-related drug and supply costs were lower for GLA than for PMX (P < 0.0001 and P = 0.046, respectively).ConclusionIn US patients with type 2 diabetes mellitus, initiating insulin with once-daily GLA, rather than a PMX, is associated with increased treatment persistence and similar clinical and hypoglycemic outcomes, but lower diabetes pharmacy and supply costs. GLA may be a more flexible option than PMX. However, these results also show suboptimal glycemic control in the real-world setting despite change in treatment regimens and call for optimization in management of patients with type 2 diabetes mellitus.

Basal insulin persistence, associated factors, and outcomes after treatment initiation among people with type 2 diabetes mellitus in the US

“…et al 10 , Cooke et al 15 , and Bonafede et al 16 , but lower than some other estimates in the literature 11,12,17 percentile of the time between the first and second refills among those with at least two refills, stratified by quantity supplied. Findings from the sensitivity analyses in the current analysis also demonstrate the effects of using different criteria used to characterize persistence: allowing for gaps in basal insulin use of up to 60 days, 90 days, 120 days, or shorter than 90th percentile of the days between two consecutive fills would respectively characterize 40%, 55%, 65%, and 44% of the sample as being persistent within the year after treatment initiation.…”

“…As a sensitivity analysis, the study estimated the proportions of patients characterized as continuers versus interrupters or discontinuers in the first year after treatment initiation, allowing for gaps of up to 60, 90, and 120 days between available days' supply. In addition, the study estimated persistence patterns in the first year after treatment initiation using an alternative definition of persistence that has been used in the literature 11,12,13,14,17 , allowing for time between refills that is less than the 90th percentile of the duration between consecutive basal insulin prescription fills for the sample, stratified by quantity supplied (<1500 units, 1500-<3000 units, and 3000 units).…”

“…For example, in a study of a large commercially insured insulin-na€ ıve population in the US, Ascher-Svanum et al found that only 18% of the people with T2DM who initiated insulin continued treatment in the year after initiation without any interruption or discontinuation 10 . With regards to basal insulin in particular, studies have found that approximately 55-80% of people with T2DM (identified from large commercial insurance databases) who were prescribed insulin glargine remained treatment persistent within the year after initiation [11][12][13][14] . In a separate study evaluating persistence with injectable antihyperglycemic medications among a managed care population, Cooke et al reported that 29% of patients initiating basal insulin or exenatide were persistent at 12 months after initiation 15 .…”

“…In yet another study, Bonafede et al found that 27% of basal insulin initiators had uninterrupted use in the year after initiation 16 . More recently, using pooled data from three different retrospective analyses of commercially insured populations, Wei et al reported that 65% of the people using insulin glargine or insulin detemir were treatment persistent within the year after initiation 17 Baser et al defined persistence as refilling the prescription within the 90th percentile of the time between the first and second refills among those with at least two refills, stratified by quantity supplied 11 . In all instances, however, people with an extended gap in insulin treatment were considered non-persistent even if they restarted therapy after initial discontinuation; a pattern commonly observed among people using insulin in the real world 10 .…”

Cost of medication adherence and persistence in type 2 diabetes mellitus: a literature review

“…A systematic review of observational studies reporting persistence with oral antidiabetes drugs (OADs) in patients with T2DM revealed a mean rate of 56.2%, with discontinuation estimates of 31.4% 7. Similarly, using claims data, rates of insulin glargine persistence in the first year after initiation of ~55.0% were reported 8,9. The reasons for T2DM medication nonadherence and nonpersistence are multifactorial and include suboptimal communication between patients and providers, inadequate patient knowledge about medications, complex regimens and follow-up, and unique issues surrounding insulin use 10.…”