Corrigendum: Real-World Treatment Patterns of Antiviral Prophylaxis for Cytomegalovirus Among Adult Kidney Transplant Recipients: A Linked USRDS-Medicare Database Study.

[This corrects the article DOI: 10.3389/ti.2022.10528.][This corrects the article DOI: 10.3389/ti.2023.12367.].

Burden of neutropenia and leukopenia among adult kidney transplant recipients: A systematic literature review of observational studies.

BACKGROUND: Leukopenia and neutropenia (L/N) may affect treatment decisions, potentially resulting in poor clinical and economic outcomes among kidney transplant recipients (KTRs). The burden of L/N is poorly quantified systematically. This systematic literature review aimed to summarize the incidence of, risk factors for, and clinical and economic outcomes associated with L/N post-KT. METHODS: We systematically searched MEDLINE, Embase, and the Cochrane Library (from database inception-June 14, 2021) and conferences (past 3 years) to identify observational studies examining epidemiology, risk factors, or outcomes associated with L/N among adult KTRs. RESULTS: Of 2081 records, 82 studies met inclusion criteria. Seventy-three studies reported the epidemiology of L/N post-KT. Pooled incidence of neutropenia, defined as absolute neutrophil counts (ANC) <1000/µl, ranged from 13% to 48% within 1-year post-transplant; ANC <500/µl ranged from 15% to 20%. Leukopenia, defined as white blood cell counts <3500/µl, was 19% to 83%. Eleven studies reported independent risk factors associated with L/N post-KT. D+/R- cytomegalovirus status, mycophenolic acid (MPA), and tacrolimus use were the most consistent risk factors across studies. Fourteen studies reported L/N-associated clinical outcomes. We noted a trend toward a positive association between neutropenia and acute rejection/opportunistic infections. Mixed findings were noted on the association between L/N and graft failure or mortality. Dosage modifications of valganciclovir, MPA, cotrimoxazole, and anti-thymoglobulin and the need for granulocyte colony-stimulating factor (G-CSF) use were common with L/N. CONCLUSION: Findings suggest post-transplant L/N were common and associated with frequent modifications of immunosuppressive agents, requiring G-CSF use, and rejection or opportunistic infections. Findings highlight the need for interventions to reduce risk of L/N post-KT.

Outcomes among CMV-mismatched and highly sensitized kidney transplants recipients who develop neutropenia.

Limited data exist on the incidence and clinical outcomes of neutropenia among kidney transplant recipients. Our study included 572 adults who received a kidney transplant at the University of California, San Francisco Medical Center between 2012 and 2018, and were CMV-mismatched or had a PRA ≥ 80%. Recipients with HIV, Hepatitis B and C, and primary non-function were excluded. Participants were followed for at least 1 year after transplantation. Neutropenia was defined as absolute neutrophil count < 1000 cells/µl. Cox proportional hazards regression models using neutropenia as a time-varying predictor were used to determine the risk of mycophenolic acid and valganciclovir changes, rejection, hospitalizations and use of granulocyte colony stimulating factor. Models were adjusted for demographics and transplant characteristics. Mean follow-up was 3.7 (SD, 1.8) years. The mean age of the cohort was 50.4 (13.1) years, and 57.5% were female. A total of 208 (36.3%) participants had neutropenia. Neutropenia was associated with an increased risk of valganciclovir or MPA dose reductions or discontinuations [adjusted hazard ratio, aHR: 7.78, 95% CI: 4.73-12.81], rejection [aHR 2.00, 95% CI: 1.10-3.64] and hospitalizations [aHR 3.32, 95% CI: 2.12-5.19]. Neutropenia occurs frequently after kidney transplantation and leads to more medication changes and adverse clinical outcomes.

Real-World Treatment Patterns of Antiviral Prophylaxis for Cytomegalovirus Among Adult Kidney Transplant Recipients: A Linked USRDS-Medicare Database Study.

Limited data exist on cytomegalovirus (CMV) antiviral treatment patterns among kidney transplant recipients (KTRs). Using United States Renal Database System registry data and Medicare claims (1 January 2011-31 December 2017), we examined CMV antiviral use in 22,878 KTRs who received their first KT from 2011 to 2016. Three-quarters of KTRs started CMV prophylaxis (85.8% of high-, 82.4% of intermediate-, and 32.1% of low-risk KTRs). Median time to prophylaxis discontinuation was 98, 65, and 61 days for high-, intermediate-, and low-risk KTRs, respectively. Factors associated with receiving CMV prophylaxis were high-risk status, diabetes, receipt of a well-functioning kidney graft, greater time on dialysis before KT, panel reactive antibodies ≥80%, and use of antithymocyte globulin, alemtuzumab, and tacrolimus. KTRs were more likely to discontinue CMV prophylaxis if they developed leukopenia/neutropenia, had cardiovascular disease, or received their kidney from a deceased donor. These findings suggest that adherence to the recommended duration of CMV-prophylaxis for high and intermediate-risk patients is suboptimal, and CMV prophylaxis is overused in low-risk patients.

The changing impact of cytomegalovirus among hematopoietic cell transplant recipients during the past decade: A single institutional cohort study.

BACKGROUND: With advancements in allogeneic hematopoietic cell transplantation (alloHCT), the need for cytomegalovirus (CMV) surveillance persists. METHODS: We present a retrospective analysis on the impact of CMV with preemptive therapy in 1065 alloHCT patients with donor and/or recipient CMV seropositivity from 2009 to 2019. RESULTS: Fifty-one percent developed clinically significant CMV infection (CMV-CSI); 6.5% had CMV disease. In multivariate analysis stratified by serostatus and preparative regimen, the use of anti-thymocyte globulin (hazard ratios 2.97, 95% confidence interval 2.00-4.42, p < .001) was associated with development of CMV-CSI. Median length of stay for index hospitalization was longer in patients with CMV-CSI (27 vs. 25 days, respectively; p = .002), as were rates (32.9% vs. 17.7%; p < .001) and duration (9 d vs. 6 d; p < .001) of rehospitalization, and median total inpatient days (28 d vs. 26 d; p < .001). Patients with CMV-CSI had higher rates of neutropenia (47% vs. 20%; p < .001) and transfusion support (packed red blood cell, median 5 vs. 3; p < .001; platelets, median 3 vs. 3; p < .001). CONCLUSION: Preemptive therapy does not negate the impact of CMV-CSI on peri-engraftment toxicity and healthcare utilization. This cohort represents a large single center study on the impact of CMV in the preletermovir era and serves as a real-world comparator for assessing the impact of future prophylaxis.

Cost-effectiveness analysis of cytomegalovirus prophylaxis in allogeneic hematopoietic cell transplant recipients from a US payer perspective.

To evaluate the cost-effectiveness of letermovir versus no prophylaxis for the prevention of cytomegalovirus infection and disease in adult cytomegalovirus-seropositive allogeneic hematopoietic cell transplantation (allo-HCT) recipients. A decision model for 100 patients was developed to estimate the probabilities of cytomegalovirus infection, cytomegalovirus disease, various other complications, and death in patients receiving letermovir versus no prophylaxis. The probabilities of clinical outcomes were based on the pivotal phase 3 trial of letermovir use for cytomegalovirus prophylaxis versus placebo in adult cytomegalovirus-seropositive recipients of an allo-HCT. Costs of prophylaxis with letermovir and of each clinical outcome were derived from published sources or the trial clinical study reports. Incremental cost-effectiveness ratios (ICERs) in terms of cost per quality-adjusted life year (QALY) gained were used in the model. One-way and probabilistic sensitivity analyses were conducted to explore uncertainty around the base-case analysis. In this model, the use of letermovir prophylaxis would lead to an increase of QALYs (619) and direct medical cost ($1 733 794) compared with no prophylaxis (578 QALYs; $710 300) in cytomegalovirus-seropositive recipients of an allo-HCT. Letermovir use for cytomegalovirus prophylaxis was a cost-effective option versus no prophylaxis with base-case analysis ICER $25 046/QALY gained. One-way sensitivity analysis showed the most influential parameter was mortality rate. The probabilistic sensitivity analysis showed a 92% probability of letermovir producing an ICER below the commonly accepted willingness-to-pay threshold of $100 000/QALY gained. Based on this model, letermovir use for cytomegalovirus prophylaxis was a cost-effective option in adult cytomegalovirus-seropositive recipients of an allo-HCT.

Epidemiology, risk factors, and outcomes associated with cytomegalovirus in adult kidney transplant recipients: A systematic literature review of real-world evidence.

Kidney transplant recipients (KTRs) have increased risk for cytomegalovirus (CMV) infection/disease given the necessity of drug-induced immunosuppression. A comprehensive review of published literature reporting real-world data on prevention strategies utilized and associated CMV burden outcomes is limited. Such data could help inform future clinical practice and identify unmet needs in CMV management. We conducted a systematic review of observational studies published in Medline or EMBASE from January 2008 to November 2018 to identify current real-world CMV management approaches, CMV infection/disease risk factors, and outcomes associated with CMV infection. Descriptive statistics and pooled quantitative analyses were conducted. From 1608 records screened, 86 citations, including 69 803 adult KTR, were included. Prophylaxis and preemptive therapy (PET) were predominant approaches among D+/R- and R + CMV serostatus transplants, respectively. Valganciclovir and ganciclovir were frequently utilized across CMV risk strata. Despite prevention approaches, approximately one-fourth of KTR developed CMV infection. Age and D+/R- CMV serostatus were consistent risk factors for CMV infection/disease. CMV infection/disease was associated with increased mortality and graft loss. CMV was similarly associated with acute rejection (AR) risk, but with high heterogeneity among studies. Limited data were available on CMV and opportunistic infections (OIs) risk. CMV remains a significant issue. New strategies may be needed to optimize CMV management.

Impact of Preemptive Therapy for Cytomegalovirus on Hospitalizations and Cost after Hematopoietic Stem Cell Transplantation.

Cytomegalovirus (CMV) viremia occurs in 40% to 80% of CMV-seropositive (R+) recipients of allogeneic hematopoietic cell transplantation (HCT). The preemptive therapy (PET) strategy has reduced the risk of CMV end-organ disease (EOD) and associated mortality but may lead to substantial healthcare resource utilization (HCRU) and costs. Real-world data on the economic impact of PET is relevant for the evaluation of alternative strategies for CMV management. We examined the impact of clinically significant CMV treated with PET on inpatient length of stay (LOS), number of readmissions, and associated costs from day 0 through day 180 post-HCT. This was a retrospective study of R+ adults who underwent peripheral blood or marrow allogeneic HCT at Memorial Sloan Kettering Cancer Center between March 2013 and December 2017. Patients were routinely screened for CMV by qPCR and received PET according to institutional standards of care. Data were extracted from electronic medical records and hospital databases. Itemized cost data per patient were obtained from the Vizient database, adjusted to 2017 dollars using inflation indices. Study outcomes included HCRU evaluated by inpatient LOS and inpatient cost in patients who received PET for clinically significant CMV (PET group) compared with those who did not receive PET (no PET group) and the frequency and cost of CMV-related readmissions compared with non CMV-related readmissions. We used generalized linear models to examine the incremental HCRU and costs associated with PET controlling for other potential factors. Of 357 patients, PET was initiated in 208 (58.3%), at a median of 35 days after HCT. By day 180, 23 patients (6.4%) had developed CMV EOD and 3 (.8%) had died of CMV. Compared with the no PET group, the PET group had a longer LOS for HCT admission (P = .0276), longer total LOS by day 180 (P = .0001), a higher number of readmissions (P = .0001), a higher mean inpatient cost for HCT admission ($189,389 versus $151,646; P = .0133), and a higher total inpatient cost ($297,563 versus $205,815; P < .0001). Among PET recipients, CMV-related readmissions were associated with higher mean cost per episode compared with non CMV-related readmissions ($165,455 versus $89,419; P = .005). CMV-related readmissions comprised 40.6% of total all-cause readmissions and incurred 55.9% of total all-cause readmission costs in PET recipients. Our data show that patients treated with currently available PET had greater inpatient HCRU and cost, by day 180 compared with patients who did not receive PET. The cost of CMV-related readmissions accounted for 56% of total readmission cost among PET recipients. Future studies are needed to examine the cost-effectiveness of alternative strategies for CMV management.

Impact of Preemptive Therapy for Cytomegalovirus on Toxicities after Allogeneic Hematopoietic Cell Transplantation in Clinical Practice: A Retrospective Single-Center Cohort Study.

(Val)ganciclovir (vGCV) or foscarnet (FCN) as preemptive therapy (PET) for cytomegalovirus (CMV) after allogeneic hematopoietic cell transplantation (HCT) is associated with myelosuppression and nephrotoxicity, respectively. We analyzed a cohort of CMV-seropositive (R+) HCT recipients managed preemptively at a single center. The objectives of our study were to (1) quantify the frequencies of neutropenia and acute kidney injury (AKI) through day +100 (D100) post-HCT and at PET discontinuation and (2) assess the impact of PET on neutropenia and AKI in multivariate models. This was a retrospective cohort study of adult CMV R+ recipients who underwent allo-HCT at Memorial Sloan Kettering Cancer Center from March 18, 2013, through December 31, 2017, and were managed with PET. Patients were grouped by receipt of PET (PET and no PET). Neutropenia and AKI were defined by Common Terminology Criteria for Adverse Events version 4. Frequencies of toxicities by D100 were compared between relevant groups. The impact of PET on toxicities was examined in univariate and multivariate Poisson/negative binomial regression models. Of 368 CMV R+ HCT recipients, 208 (56.5%) received PET. Neutropenia by D100 occurred in 41.8% and 28.6% patients in PET and no PET, respectively (P = .0009). PET increased the risk of neutropenia (adjusted relative risk = 1.81; 95% confidence interval [CI], 1.48 to 2.21; P < .0001) in multivariate analyses. AKI by D100 occurred in 12.0% and 7.8% patients in PET and no PET, respectively (P = .19). PET increased the risk of AKI by 2.75-fold (95% CI, 1.71 to 4.42; P < .0001). When PET recipients were grouped by first antiviral, neutropenia by D100 occurred in 34.8% and 48.9% of vGCV and FCN recipients, respectively, (P = .08), and AKI occurred in 13.0% and 34.0% of vGCV and FCN recipients, respectively (P = .001). At discontinuation of vGCV or FCN, neutropenia was present in 11.2% versus 2.1% patients, respectively (P = .08), and AKI was present in 1.9% of versus 12.8% patients respectively (P = .005). Preemptive therapy for CMV increased the risk of neutropenia and AKI in the first 100 days post-HCT by 1.8-fold and 2.8-fold, respectively. Our results underscore the need for safer antivirals for CMV management in HCT recipients.

Direct medical costs of severe hypoglycaemic events in patients with type 2 diabetes in England: A retrospective database study.

AIMS: Hypoglycaemia in patients with diabetes can be induced by insulins and sulfonylureas. We assessed the real-world impact of specific monotherapy and combination regimens on hypoglycaemic events requiring hospitalisation and related secondary costs to the English healthcare system. METHODS: This retrospective observational study used the Clinical Practice Research Datalink with linked hospital admission data during 2008-2012. Patients with type 2 diabetes mellitus (T2DM) using antihyperglycaemic agents (AHAs) were assigned to mutually exclusive subgroups (insulin- and non-insulin-containing regimens; treatment groups of interest; age group) based on treatment at index date (date of first AHA prescription). Outcomes were number and cost of hospital admissions with hypoglycaemic event-related diagnosis codes. RESULTS: We identified 110 206 patients with T2DM (mean age 64.9 years, time since diagnosis 5.4 years, HbA1c at index 7.4%), with 439 hypoglycaemic events requiring inpatient hospitalisation (mean length of stay 6.3 days, mean cost/stay £1351). Event rates and cost of stay were highest in patients treated with sulfonylurea- or insulin-based regimens. Event rates, duration and cost of stay were higher in older patients. CONCLUSION: Rates of severe hypoglycaemic events varied substantially between T2DM regimens. In this study of patients treated in clinical practice in England, sulfonylurea- and insulin-based regimens were associated with the highest event rates and costs associated with hospitalisation for severe hypoglycaemic events; hospitalisation for severe hypoglycaemic events was not observed with dipeptidyl peptidase-4 inhibitor monotherapy or with metformin.

Increased statin prescribing does not lower pneumonia risk.

BACKGROUND: Investigators have attributed protective effects of statins against pneumonia and other infections. However, these reports are based on observational data where treatments are not assigned randomly. We aimed to determine if the protective effects of statins against pneumonia are due to nonrandom treatment assignment. METHODS: We built a cohort consisting of 124 695 Medicare beneficiaries diagnosed with an acute myocardial infarction (AMI) for which we had complete claims data. We considered patients who survived at least 30 days post-AMI (full sample), or who survived for 1 year post-AMI (survivors). First, we used ordinary least squares (OLS) and logit models to determine if receiving a statin was protective against pneumonia. Second, to control for nonrandom treatment assignment, we performed an instrumental variables analysis using geographic treatment rates as an instrument. All models included patient demographics, medications, diagnoses, length of hospital stay, and out-of-pocket drug costs as covariates. Our outcome measure was a pneumonia diagnosis during the 1 year following AMI. RESULTS: A total of 76 994 patients (61.9%) filled a statin prescription, and 19 078 (15.3%) were diagnosed with pneumonia. Using OLS, the statin coefficient was -0.016 (P < .001), indicating that statins are associated with a reduction in pneumonia. Using instrumental variables, we find that statin prescriptions are not associated with a reduction in pneumonia. For the full sample, statin coefficients ranged from -0.001 to -0.01 (P > .6). CONCLUSIONS: For patients with AMI, the protective effect of statins against pneumonia is most likely the result of nonrandom treatment assignment (ie, a healthy-user bias).

Real-World Outcomes Associated With Letermovir Use for Cytomegalovirus Primary Prophylaxis in Allogeneic Hematopoietic Cell Transplant Recipients: A Systematic Review and Meta-analysis of Observational Studies.

Background: A systematic review and meta-analysis of real-world observational studies was conducted to summarize the impact of letermovir cytomegalovirus (CMV) primary prophylaxis (PP) among adult allogeneic hematopoietic cell transplant (allo-HCT) recipients. Methods: Systematic searches in Medline/PubMed, Embase, and conferences (from database inception to October 2021) were conducted to identify studies for inclusion. Random-effects models were used to derive pooled estimates on the relative effectiveness of letermovir PP compared to controls. Results: Forty-eight unique studies (N = 7104 patients) were included, most of which were comparative, single-center, and conducted in the United States. Letermovir PP was associated with statistically significant reduction in odds of CMV reactivation (pooled odds ratio [pOR], 0.13 and 0.24; P < .05), clinically significant CMV infection (pOR, 0.09 and 0.19; P < .05), and CMV disease (pOR, 0.31 and 0.35; P < .05) by day +100 and day +200 after allo-HCT, respectively. Letermovir PP was associated with significantly lower odds of all-cause (pOR, 0.73; P < .01) and nonrelapse mortality (pOR, 0.65; P = .01) beyond day 200 after allo-HCT. Conclusions: Letermovir for CMV PP was effective in reducing the risk of CMV-related complications overall and mortality beyond day 200 among adult allo-HCT recipients.

Does bargaining affect Medicare prescription drug plan reimbursements to independent pharmacies?

OBJECTIVE: To examine how pharmacy bargaining activities affect reimbursement rates in Medicare Part D prescription drug plan (PDP) contracts, controlling for pharmacy quality attributes, market structures, and area socioeconomic status. DESIGN: Cross-sectional study. SETTING: Six Medicare regions throughout the United States between October and December 2009. PARTICIPANTS: Random sample of 1,650 independent pharmacies; 321 returned surveys containing sufficient responses for analysis. INTERVENTION: Pharmacies were surveyed regarding PDP reimbursement rates, costs, and cash prices of two popular prescription drugs (atorvastatin calcium [Lipitor-Pfizer] and lisinopril, 1-month supply of a common strength), as well as pharmacy bargaining activities and quality attributes. Data also were used from the National Council for Prescription Drug Programs pharmacy database, the 2000 U. S. Census, and the 2006 Economic Census on local market structures and area socio-economic status. MAIN OUTCOME MEASURE: PDP reimbursement rates. RESULTS: For the brand-name drug atorvastatin calcium, the PDP reimbursement was positively related to a pharmacy's request for a contract change (ß = 0.887, P < 0.05), whereas other bargaining activities were not significantly related to PDP reimbursement. However, for the generic drug lisinopril, no bargaining activities were found to be significantly related to the PDP reimbursement. CONCLUSION: Pharmacy request for a contract change was associated with higher reimbursement rates for the brand-name drug atorvastatin calcium in PDP contracts, after controlling for pharmacy quality attributes, local market structures, and area socioeconomic status; this finding likely applies to other brand-name drugs because of the structure of the contracts. Our results suggest that independent pharmacies are more likely to acquire higher reimbursement rates by engaging in active bargaining with third-party payers.

Antiviral treatment approaches for cytomegalovirus prevention in kidney transplant recipients: A systematic review of randomized controlled trials.

Various CMV anti-viral (AV) preventive strategies have been utilized in KTRs. We examined efficacy, safety and costs of CMV-AV prevention strategies in KTRs using a systematic literature review (SLR) of randomized controlled trials (RCTs) publications indexed in MEDLINE and Embase (from inception to November 2018). Thirty RCTs met inclusion criteria with 22 unique AV preventive strategies. Prophylaxis was associated with significantly lower rates of CMV infection/disease (CMVi/d) compared to no prophylaxis (pooled odds ratio, pOR with 95% confidence interval (CI): CMVi: 0.33; 0.19, 0.57; CMVd: 0.27; 0.19; 0.39). Preemptive therapy (PET) had lower rates of CMVd (0.29; 0.11, 0.77), and medical costs compared to no PET. Prophylaxis had significantly lower rates of early CMVi/d, and higher rates of late CMVi and hematological adverse events (leukopenia, 2.93; 1.22, 7.04), and similar overall medical costs compared to PET. Studies involving head-to-head comparison of different prophylaxis approaches showed mixed findings with respect to optimum dose, duration and route of administration on CMV outcomes. Although there was heterogeneity across populations and interventions, both prophylaxis and PET strategies reduced CMVi/d compared to no prophylaxis/PET and had differential safety profile in terms of hematological adverse events. For comprehensiveness we did not limit study inclusion based on date; the wide time-period may have contributed to the heterogeneity in prevention approaches which subsequently made pooling studies a challenge. Despite demonstrated efficacy of prophylaxis/PET, our findings highlight the potential need of a novel intervention with a better safety profile and perhaps improved outcomes.

Impact of Letermovir Use for Cytomegalovirus Prophylaxis on Re-Hospitalization Following Allogeneic Hematopoietic Stem Cell Transplantation: An Analysis of a Phase III Randomized Clinical Trial.

BACKGROUND: Allogeneic hematopoietic stem cell transplantation (HSCT) is associated with substantial healthcare resource use, particularly when recipients develop cytomegalovirus (CMV) infection. Letermovir reduced post-HSCT CMV infection risk compared with placebo in a previous phase III trial. This analysis evaluated letermovir's impact on re-hospitalization post-transplant. METHODS: Using data from a phase III, multicenter, randomized clinical trial (NCT02137772, registered May 14, 2014), this study assessed CMV-associated and all-cause re-hospitalizations at weeks 14, 24, and 48 post-transplant among recipients of letermovir versus placebo. Unstandardized re-hospitalization rates and days were reported; standardized rates and days were estimated accounting for censoring due to death or early study discontinuation. RESULTS: Unstandardized rates (95% confidence interval [CI]) of all-cause re-hospitalization in letermovir versus placebo recipients at weeks 14, 24, and 48 were 36.6% (31.4-42.1) versus 47.6% (39.9-55.4), 49.2% (43.7-54.8) versus 55.9% (48.1-63.5), and 55.7% (50.1-61.2) versus 60.6% (52.8-68.0), respectively. Unstandardized mean total duration (95% CI) of re-hospitalization with letermovir versus placebo at weeks 14, 24, and 48 were 7.6 (5.9-9.8) versus 11.3 (8.6-14.8), 13.9 (11.2-17.2) versus 15.5 (11.9-20.1), and 18.0 (14.8-21.9) versus 20.7 (15.8-27.1) days, respectively. Similar results were found in CMV-associated re-hospitalization outcomes and standardized rates and days of all-cause re-hospitalizations. CONCLUSIONS: In this post-hoc analysis, letermovir was associated with lower rates of CMV-associated and all-cause re-hospitalizations with a shorter length of stay (especially within the first 14 weeks post-transplant).

Metformin adherence and discontinuation among patients with type 2 diabetes: A retrospective cohort study.

AIMS: To describe discontinuation and adherence to metformin in the United Kingdom. METHODS: This was a retrospective analysis of data from the Clinical Practice Research Datalink database of type 2 diabetes patients aged ≥18 years with ≥1 metformin prescription in 2013. Metformin use was assessed in new and ongoing users, defined, respectively, as not having or having a prescription for metformin in the baseline period. Discontinuation was assessed in all patients and adherence in patients who did not discontinue metformin. Factors predictive of discontinuation and adherence were assessed. RESULTS: Discontinuation among new and ongoing users was 35.9% and 23.1%, respectively. Among the continuers of metformin treatment, the adherence rate was 40.5% and 44.3% among new and ongoing users, respectively. Among new users, baseline use of DDP-4 inhibitors (HR 1.276) and diabetes duration (HR 1.013) were associated with an increased risk of discontinuation, whereas increased age (HR 0.997), concomitant lipid-lowering therapy (HR 0.956), macrovascular disease (HR 0.952), and chronic kidney disease (HR 0.952) were associated with a decreased risk of discontinuation among ongoing users. Variables positively associated with adherence in both user groups were (HR values for all patients) age (1.021), smoking status (1.188), and baseline comorbidities: chronic kidney disease, depression, dementia, and chronic obstructive pulmonary disease (1.106, 1.192, 2.27, and 1.211, respectively), while obesity (0.936) and HbA1c 8.0-8.9% (0.862; reference <6.5%) were negatively associated with adherence. CONCLUSIONS: About one-third of patients initiating metformin discontinued within 12 months and fewer than 50% of all patients are adherent to metformin.

Effect of Dipeptidyl Peptidase 4 Inhibitors Used in Combination with Insulin Treatment in Patients with Type 2 Diabetes: A Systematic Review and Meta-analysis.

INTRODUCTION: To evaluate the efficacy and safety of dipeptidyl peptidase 4 inhibitors (DPP4i) used in combination with insulin in patients with type 2 diabetes mellitus (T2DM). METHODS: We searched the MEDLINE, Embase, and Cochrane library databases for randomized controlled trials (RCTs) published through June 2018. Studies with at least a 12-week treatment period were included to compare the addition of DPP4i to insulin with insulin control therapy. Meanwhile, groups on a stable insulin dosage (insulin-stable subgroup) or titrating insulin dosage (insulin-flexible subgroup) were analyzed separately. RESULTS: Twenty-one RCTs with 3697 patients randomized to a DPP4i/insulin treatment arm and 3538 to an insulin control arm were included. DPP4i, when added to insulin therapy, led to a significantly greater reduction in HbA1c (- 0.57%, 95% CI - 0.66, - 0.48) and provided significantly greater odds of achieving the HbA1c target < 7% (OR 3.45; 95% CI 2.58, 4.63). These effects were achieved in the context of a decrease in the daily insulin requirement, without increases in hypoglycemia risk and body weight, compared with the control treatment. Subgroup analysis showed control-adjusted reductions in HbA1c from baseline in the insulin-stable subgroup (-  0.64%; 95% CI - 0.74, - 0.53) and the insulin-flexible subgroup (- 0.43%; 95% CI - 0.56, - 0.30). Other results occurred similarly in both subgroups. CONCLUSIONS: The addition of DPP4i to insulin is associated with a statistically significant reduction in glycemic control as measured by HbA1c, fasting plasma glucose, and 2-h postprandial glucose, without increasing the risk of hypoglycemia and weight gain. These conclusions were also observed in both stable-dose and flexible-dose insulin subgroups.

Association Between Switching to a High-Deductible Health Plan and Discontinuation of Type 2 Diabetes Treatment.

Importance: High-deductible health plans (HDHPs) are a common cost-savings option for employers but may lead to underuse of necessary treatments because beneficiaries bear the full cost of health care, including medications, until a deductible is met. Objectives: To evaluate the association between switching from a non-HDHP to an HDHP and discontinuation of antihyperglycemic medication and to assess whether the association differs in patients using branded vs generic antihyperglycemic medications. Design, Setting, and Participants: This retrospective matched cohort study used administrative claims from MarketScan databases to identify commercially insured adult patients with type 2 diabetes who used at least 1 antihyperglycemic medication in 2013. Patients in the HDHP cohort (n = 1490) were matched by propensity scores to a non-HDPH control cohort (n = 1490). Data were collected and analyzed from January 1, 2013, through December 31, 2014. Exposures: Switching from a non-HDHP in 2013 to a full replacement HDHP in 2014 (no non-HDHP option offered) vs staying on a non-HDHP. Main Outcomes and Measures: Difference-in-differences models estimated discontinuation of branded and generic antihyperglycemic medications. Results: Among the 2980 patients included in the analysis (1932 men [64.8%]; mean [SD] age, HDHP cohort: 52.6 [6.9] years; non-HDHP cohort: 52.7 [7.3] years), no difference between the HDHP and non-HDHP cohorts was found in unadjusted follow-up discontinuation rates for all antihyperglycemic medications (255 [22.7%] vs 255 [23.3%]; P = .72); however, among patients using branded medication, a significantly greater proportion of patients in the HDHP group did not refill branded medications (81 of 396 [20.5%] vs 61 of 437 [14.0%]; P = .009). Difference-in-differences models were not statistically significant. Conclusions and Relevance: These findings suggest switching to an HDHP is associated with discontinuation specifically of branded medications. Unintended health consequences may result and should be considered by employers making health care benefit decisions.

Retrospective Cohort Analysis of the Reduced Burden of Hypoglycemia Associated with Dipeptidyl Peptidase-4 Inhibitor Use in Patients with Type 2 Diabetes Mellitus.

INTRODUCTION: The use of antihyperglycemic agents (AHA), especially insulin and sulfonylureas (SU), is a risk factor for hypoglycemia. Despite the significant clinical and economic burdens associated with hypoglycemia and the decreasing use of SU in favor of other oral AHA, relatively little is known about hypoglycemia trends specific to the use of non-insulin AHA. We sought to estimate annual hypoglycemia event rates and costs among patients with type 2 diabetes mellitus (T2DM) who started either SU or dipeptidyl peptidase-4 inhibitors (DPP-4i) and to predict rates and costs in the absence of DPP-4i. METHODS: Truven's MarketScan Commercial Claims database was used to estimate hypoglycemia event rates and costs from 2007 to 2013. Hypoglycemia, defined using diagnosis codes, was assessed during the 12 months following SU (n = 245,201) or DPP-4i (n = 176,786) initiation by adults with T2DM. Coefficients from a Poisson regression model used to estimate the impact of patient characteristics on hypoglycemia rates for patients who started SU were used to predict rates for patients who started DPP-4i had they started SU instead. RESULTS: Hypoglycemia events per 100 patient-years (costs per event) ranged from 5.4 ($565) in 2007 to 10.4 ($1154) in 2013 for patients starting SU; rates (costs) for patients starting DPP-4i ranged from 3.2 ($308) in 2007 to 6.4 ($482) in 2013. Predicted hypoglycemia rates would have been 5.3-9.9 per 100 person-years for patients who started DPP-4i had they started SU instead. Starting DPP-4i, rather than SU, would have resulted in national savings of $750.3 million in healthcare costs due to avoided hypoglycemia events during this period. CONCLUSIONS: Hypoglycemia rates and costs were consistently higher for patients who started SU rather than DPP-4i. The overall burden of hypoglycemia could be lowered substantially in the USA if, when feasible, patients with T2DM initiate DPP-4i instead of SU. FUNDING: Merck & Co., Inc., Kenilworth, NJ USA.

Effect of Medication Copayment on Adherence and Discontinuation in Medicare Beneficiaries with Type 2 Diabetes: A Retrospective Administrative Claims Database Analysis.

INTRODUCTION: Nonadherence to antihyperglycemic agents (AHAs) increases the incidence of morbidity and mortality, as well as healthcare-related costs, in patients with type 2 diabetes (T2D). This study examined the association between medication copayment and adherence and discontinuation among elderly patients with T2D who use generic versus branded AHAs. METHODS: A retrospective, observational cohort study used Medicare administrative claims data (index period: 1 June 2012 to 31 December 2013). Drug copayments were measured as the copayment of the index medication for a 30-day supply after patients met their plan deductible. Patients were stratified into a branded or generic cohort based on the index medication. Adherence was measured by the proportion of days covered (≥ 80%) and discontinuation by a treatment gap of > 60 days in 10 months during the follow-up period. Poisson regressions were conducted for medication adherence and discontinuation, while controlling for demographic, clinical, and comorbid conditions. RESULTS: Overall, 160,250 patients on AHA monotherapy were included in the analysis; 131,594 (82%) were prescribed a generic and 28,656 (18%) a branded AHA with a mean copay of $6 and $41, respectively. Increases in copayment increased nonadherence and discontinuation for branded medications but not for generic AHA medications. In both cohorts, elderly patients (≥ 75 years of age) had a lower risk of nonadherence and discontinuation. Black patients had a higher risk of nonadherence or discontinuing medication. Patients having more frequent inpatient, emergency room, and/or physician visits were at higher risk of nonadherence or discontinuing therapy in the branded and generic cohorts (P < 0.001). CONCLUSION: The impact of drug copayment on adherence and discontinuation varied considerably between branded and generic AHAs. Medicare patients taking branded AHAs had a higher risk of nonadherence with increasing copayment and were more likely to discontinue medication, whereas this association was not observed in patients taking generic medications. FUNDING: Merck & Co, Inc., Kenilworth, NJ, USA. Plain language summary available for this article.