Early Discontinuation and Restart of Insulin in the Treatment of Type 2 Diabetes Mellitus

Abstract

IntroductionAlthough the largest improvement in glycemic control occurs within the first 90 days of insulin therapy, little is known about early persistence on insulin therapy. This research aimed to identify predictors of early discontinuation and of subsequent restart of basal or mixture insulin among patients with type 2 diabetes mellitus (T2DM) and to assess the economic cost associated with such behaviors over a 1-year period.MethodsTruven’s Health Analytics Commercial Claims and Encounters database was utilized for the study. Logistic regressions were used to examine factors associated with early discontinuation of insulin (basal or mixture) and, among patients who discontinued early, the factors associated with restarting. Cost regressions were estimated using generalized linear models with a gamma distribution and logistic link. Kaplan–Meier survival curves were used to examine time to discontinuation and time to restart among those who discontinued.ResultsMultivariate analyses revealed that patient characteristics, prior healthcare resource utilization, comorbid diagnoses, and type of initiated insulin were associated with early discontinuation of insulin and of restarting among patients who discontinued early. Acute care (hospitalization and emergency room) costs were 9.6% higher among patients who discontinued early (P < 0.001), although outpatient, drug, and total costs were significantly lower among individuals who discontinued early. Among the early discontinuation subgroup, restarting insulin was associated with higher costs. Specifically: 11.3% higher acute care costs (P < 0.001), 24.0% higher outpatient costs (P < 0.001), 80.2% higher drug costs (P < 0.001), and 30.3% higher total costs (P < 0.001), compared to patients who discontinued early but did not restart insulin therapy in the 1-year post-period.ConclusionAmong patients with T2DM who were initiated on insulin therapy, early discontinuation of insulin and its subsequent restart were associated with significantly higher acute care costs, which may signal a more complex and challenging subgroup of patients who tend to be less engaged in outpatient care and may have poorer long-term outcomes.Electronic supplementary materialThe online version of this article (doi:10.1007/s13300-014-0065-z) contains supplementary material, which is available to authorized users.

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

“…This may in part be due to suboptimal persistence with insulin treatment in the real world care setting. 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] .…”

“…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 . Therefore, it is important to gain a better understanding of the rates of basal insulin interruption and discontinuation separately.…”

“…Furthermore, there remains an inconsistency in the findings of previous studies that evaluated factors associated with insulin persistence. For example, older age has been consistently shown to be associated with increased likelihoods of insulin persistence 10,15,17 . Two studies found a significant association between other factors such as male gender, use of multiple classes of antihyperglycemic medications, and use of multiple classes of all-cause medications during baseline with increased likelihoods of persistence 10,16 , while another study did not.…”

“…With regards to the outcomes of insulin non-persistence, the literature has consistently documented that discontinuation of insulin therapy was associated with increased use of medical services, especially acute care, and lower pharmacy use in the year after insulin initiation compared with continuation of treatment as prescribed 10,12,17 . However, because the majority of patients use insulin intermittently (as opposed to discontinuing altogether) and therefore possibly continue to attain some benefits associated with insulin treatment, there is a need to understand the implications associated with treatment interruption and discontinuation separately, relative to continuous use.…”

Early Discontinuation and Related Treatment Costs After Initiation of Basal Insulin in Type 2 Diabetes Patients

“…A database study from the US indicated that early discontinuation of insulin (basal or premixed insulin) in type 2 diabetes was related to approximately 10% higher acute health care costs compared to patients who did continue their insulin therapy. 9 However, the costs related to early discontinuation from BOT (insulin glargine vs NPH ) have not yet been assessed. Therefore, the objective of this study is to describe the cost consequences of early discontinuation from initial basal insulin treatment (glargine, NPH insulin) in type 2 diabetes patients under real-world conditions in Germany.…”