Magaly Perez-Nieves

A systematic literature review of methodologies used to assess medication adherence in patients with diabetes

Abstract Objective: Adhering to prescribed medication is often a problem for patients with diabetes yet there is no consensus on how best to measure adherence in this patient population. This systematic literature review critically reviewed and summarized the methods used to measure medication adherence in patients with diabetes (on oral hypoglycemic agents [OHAs] and/or insulin) in original research published between 2007–2013. Study design: Literature review. Methods: A systematic search for methods to assess medication adherence in patients with type I or type II diabetes was conducted using PubMed, EMBASE, PsychInfo, and Cochrane databases. Two researchers independently screened abstracts for initial eligibility and then applied the inclusion/exclusion criteria to the relevant full-text articles. Results: Fifty-nine articles met the criteria for inclusion. Subjective assessment (observer-reported and patient-reported), pill counts, Medication Event Monitoring System (MEMS), cell-phone real-time assessment, and logbooks were used in prospective studies. In pharmacy claims databases, medication possession ratios (MPRs), or some derivation thereof, were utilized. Each method has strengths and weaknesses, but few approaches specifically addressed issues unique to assessing insulin adherence. Three novel approaches (using cell-phone real-time assessment, computerized logbooks, and a questionnaire about different dosing irregularities) provided insight on timing and dosing issues that could be useful for highlighting interventions to improve insulin adherence. Conclusion: No gold standard exists for measuring medication adherence in patients with diabetes. The plethora of adherence methods precludes the comparison of adherence rates across studies. Greater consistency is therefore needed in adherence measurement, including question content, recall period, and response options for self-report measures. Novel methods for understanding adherence to variable-dosed insulin require further research. Researchers should select a methodology that best fits their research question, study design, patient population and resources.

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

Abstract Objective To assess basal insulin persistence, associated factors, and economic outcomes for insulin-naïve people with type 2 diabetes mellitus (T2DM) in the US. Research design and methods People aged ≥18 years diagnosed with T2DM initiating basal insulin between April 2006 and March 2012 (index date), no prior insulin use, and continuous insurance coverage for 6 months before (baseline) and 24 months after index date (follow-up period) were selected using de-identified administrative claims data in the US. Based on whether there were ≥30 day gaps in basal insulin use in the first year post-index, patients were classified as continuers (no gap), interrupters (≥1 prescription after gap), and discontinuers (no prescription after gap). Main outcome measures Factors associated with persistence – assessed using multinomial logistic regression model; annual healthcare resource use and costs during follow-up period – compared separately between continuers and interrupters, and continuers and discontinuers. Results Of the 19,110 people included in the sample (mean age: 59 years, ∼60% male), 20% continued to use basal insulin, 62% had ≥1 interruption, and 18% discontinued therapy in the year after initiation. Older age, multiple antihyperglycemic drug use, and injectable antihyperglycemic use during baseline were associated with significantly higher likelihoods of continuing basal insulin. Relative to interrupters and discontinuers, continuers had fewer emergency department visits, shorter hospital stays, and lower medical costs (continuers:

Incidence, prevalence, and trend analysis of the use of insulin delivery systems in the United States (2005 to 2011)

10,890, interrupters:

Correlates of basal insulin persistence among insulin-naïve people with type 2 diabetes: results from a multinational survey

13,674, discontinuers:

Basal Insulin Persistence, Associated Factors, and Outcomes After Treatment Initiation Among People With Type 2 Diabetes Mellitus In Japan

13,021), but higher pharmacy costs (continuers:

Basal insulin initiation use and experience among people with type 2 diabetes mellitus with different patterns of persistence: results from a multi-national survey

7449, interrupters:

Insulin non-persistence among people with type 2 diabetes: how to get your patients to stay on insulin therapy

5239, discontinuers:

Economic outcomes with the conversion of insulin delivery methods in hospitals

4857) in the first year post-index (p < 0.05 for all comparisons). Total healthcare costs were similar across the three cohorts. Findings for the second year post-index were similar. Conclusions The majority of people in this study interrupted or discontinued basal insulin treatment in the year after initiation; and incurred higher medical resource use and costs than continuers. The findings are limited to the commercially insured population in the US. In addition, persistence patterns were assessed using administrative claims as opposed to actual medication-taking behavior and did not account for measures of glycemic control. Further research is needed to understand the reasons behind basal insulin persistence and the implications thereof, to help clinicians manage care for T2DM more effectively.

Costs of Type 1 Diabetes Mellitus in Pediatric Patients in Spain: Chrystal Observational Study

Abstract Objective: Estimate the incidence and prevalence rates and assess overall trends among patients with diabetes using insulin vial/syringe and pens over time. Methods: A retrospective study was conducted using the Truven MarketScan database from 1 July 2004 to 31 December 2011. The database contained medical and pharmacy claims of >20 million US residents insured by commercial health plans. Patients with diabetes who utilized vial/syringe and pens were included. Incidence rate was defined as the proportion of patients initiating a new insulin type for the first time with vial/syringe and pens within each year from 2005 to 2011 among the total number of patients initiating that particular insulin type for the first time. Prevalence rate was defined as the proportion of patients using vial/syringe or pens among patients with diabetes using that insulin type within each year from 2005 to 2011. A linear trend over time was assessed by Cochran–Armitage Trend tests and Generalized Estimating Equations. Results: Incidence of patients initiating vial/syringe decreased from 2005 to 2011 (basal analog [90.5% to 31.3%]; mealtime analog [67.6% to 37.1%]), while patients initiating pens increased (basal analog [9.5% to 68.7%]; mealtime analog [32.4% to 62.9%]). There was a significant trend over time indicating increased usage of pens relative to vial/syringe; the number of pen users increased (all p < 0.0001 except mealtime human). Prevalence of patients using vial/syringe decreased from 2005 to 2011 (basal analog [93.8% to 41.2%]; mealtime analog [71.0% to 50.6%]), while patients using pens increased (basal analog [6.2% to 58.8%]; mealtime analog [29.0% to 49.4%]). From 2005 to 2011, patients were more likely to use pens than vial/syringe (all p < 0.0001 except for human mixtures and mealtime human). Conclusions: The incidence and prevalence of patients using the traditional vial/syringe decreased over time, while the use of pens increased. Some patient populations may be under-represented, limiting generalizability of results.

Cardiovascular risk profiles in Type 2 diabetes and the impact of geographical setting

Abstract Background and objective: People with T2DM who initiate basal insulin therapy often stop therapy temporarily or permanently soon after initiation. This study analyzes the reasons for and correlates of stopping and restarting basal insulin therapy among people with T2DM. Methods: An online survey was completed by 942 insulin-naïve adults with self-reported T2DM from Brazil, France, Germany, Japan, Spain, UK, and US. Respondents had initiated basal insulin therapy within the 3–24 months before survey participation and met criteria for one of three persistence groups: continuers had no gaps of ≥7 days in basal insulin treatment; interrupters had at least one gap in insulin therapy of ≥7 days within the first 6 months after initiation and had since restarted basal insulin; and discontinuers stopped using basal insulin within the first 6 months after initiation and had not restarted. Results: Physician recommendations and cost were strongly implicated in patients stopping and not resuming insulin therapy. Continuous persistence was lower for patients with more worries about insulin initiation, greater difficulties and weight gain while using insulin, and higher for those using pens and perceiving their diabetes as severe. Repeated interruption of insulin therapy was associated with hyperglycemia and treatment burden while using insulin. Resumption and perceived likelihood of resumption were associated with hyperglycemia upon insulin cessation. Perceived likelihood of resumption among discontinuers was associated with perceived benefits of insulin. Conclusion: Better understanding of the risk factors for patient cessation and resumption of basal insulin therapy may help healthcare providers improve persistence with therapy.