Determining initial and follow-up costs of cardiovascular events in a US managed care population.

BACKGROUND: Cardiovascular (CV) events are prevalent and expensive worldwide both in terms of direct medical costs at the time of the event and follow-up healthcare after the event. This study aims to determine initial and follow-up costs for cardiovascular (CV) events in US managed care enrollees and to compare to healthcare costs for matched patients without CV events. METHODS: A 5.5-year retrospective matched cohort analysis of claims records for adult enrollees in ~90 US health plans. Patients hospitalized for first CV event were identified from a database containing a representative sample of the commercially-insured US population. The CV-event group (n = 29,688) was matched to a control group with similar demographics but no claims for CV-related events. Endpoints were total direct medical costs for inpatient and outpatient services and pharmacy (paid insurance amount). RESULTS: Overall, mean initial inpatient costs were US dollars ($) 16,981 per case (standard deviation [SD] = $20,474), ranging from $6,699 for a transient ischemic attack (mean length of stay [LOS] = 3.7 days) to $56,024 for a coronary artery bypass graft (CABG) (mean LOS = 9.2 days). Overall mean health-care cost during 1-year follow-up was $16,582 (SD = $34,425), an excess of $13,792 over the mean cost of matched controls. This difference in average costs between CV-event and matched-control subjects was $20,862 and $26,014 after two and three years of follow-up. Mean overall inpatient costs for second events were similar to those for first events ($17,705/case; SD = $22,703). The multivariable regression model adjusting for demographic and clinical characteristics indicated that the presence of a CV event was positively associated with total follow-up costs (P < 0.0001). CONCLUSIONS: Initial hospitalization and follow-up costs vary widely by type of CV event. The 1-year follow-up costs for CV events were almost as high as the initial hospitalization costs, but much higher for 2- and 3-year follow-up.

Incremental cardiovascular costs and resource use associated with diabetes: an assessment of 29,863 patients in the US managed-care setting.

BACKGROUND: Patients with type 2 diabetes are at increased risk of cardiovascular events, and there is an associated economic burden attached to this risk. We conducted a retrospective claims database analysis to evaluate incremental cardiovascular costs in diabetic versus non-diabetic patients hospitalized for a cardiovascular event. METHODS: Patients hospitalized for a cardiovascular event between January 1, 2001 and June 30, 2005 were identified from a large US managed-care population. Diabetic patients were identified by evidence of type 2 diabetes in the 12 months prior to the index hospitalization. Direct medical costs and resource use - including inpatient expenditures (for the index and first recurrent hospitalizations), as well as outpatient, laboratory, and pharmacy expenditures (during the 3-year follow-up period) - were determined for patients with or without diabetes. RESULTS: Of the 29,863 patients identified with a cardiovascular hospitalization, 5,501 patients (18.4%) had a history of diabetes in the pre-index period (mean age, 57.8 years; 42.1% female). The overall mean follow-up period was 22.8 months. The incidence of subsequent cardiovascular events in the first year of follow-up was significantly higher for patients with diabetes compared with non-diabetic patients for all types of cardiovascular events except angina. Compared with non-diabetic patients, patients with diabetes had similar mean direct medical costs per patient for the index cardiovascular hospitalization ($17,435 versus $16,917; P = 0.09), and the first recurrent cardiovascular hospitalization ($18,488 versus $17,481; P = 0.2), yet higher mean total direct medical costs per patient for cardiovascular events during follow-up years (Year 1: $8,805 versus $6,982; Year 2: $13,860 versus $10,056; Year 3: $16,149 versus $12,163; all P < or = 0.0002). The cost difference between diabetic and non-diabetic patients remained significant after adjusting for age, gender and other potential confounders in multivariate regression analysis. The mean (SD) total period of inpatient cardiovascular hospitalization after 3 years of follow-up was 3.3 (12.4) days for patients with diabetes compared with 1.8 (5.8) days for non-diabetic patients (P < 0.0001). CONCLUSION: Diabetic patients hospitalized for a cardiovascular event incur higher costs for cardiovascular care than their non-diabetic counterparts. This analysis of the incremental cardiovascular cost and resource use provides the basis for greater accuracy and precision when modeling the economic value of initiatives aimed at reducing cardiovascular morbidity in patients with diabetes mellitus.

Generic and therapeutic statin switches and disruptions in therapy.

BACKGROUND: The study objective was to compare dose-equivalence, adherence and subsequent switch rates among patients recently switched from a branded to generic version of the same statin (generic substitution, GS) vs. those switched from branded statin to generic version of a different statin (therapeutic substitution, TS). METHODS: In a retrospective cohort analysis among adult enrollees in over 90 US health plans, the authors identified adult patients who switched from a branded to generic statin from July-December 2006 (simvastatin became generic in June 2006). Patients were classified by type of statin switch: GS (e.g., branded simvastatin --> generic simvastatin), and TS (e.g., branded atorvastatin --> generic simvastatin). Demographic and clinical data were collected from claims before switch through 6 months follow-up. Separate outcomes of interest included proportion of patients that switched to a less potent daily dose, that switched back to previous branded statin after switch, and that were at least 80% adherent during the 6 months after initial switch. Significant predictors of each clinical outcome were identified using multivariable logistic regression models, adjusting for differences between groups in covariates and potential confounders. RESULTS: The 6-month TS (n = 3807) and GS (n = 40,165) groups were generally similar demographically. Compared to GS, TS patients were significantly more likely to be switched to a less potent dose (26.2% vs. 0.5%, adjusted odds ratio [AOR] in patients with high-potency index medication = 83.4, p < 0.0001); 33% less likely to be adherent in the 6 months after switch (67.7% vs. 75.9%, AOR in patients with no switch in first 6 months follow-up = 0.67, p < 0.0001); and four times more likely to switch back to previous branded statin (11.3% vs. 2.9%, AOR = 4.1, p < 0.0001). LIMITATIONS: This study did not account for co-payment changes, lipid measurements, or changes in pill burden. CONCLUSIONS: While this study did not have data on why patients had TS (e.g., for cost or clinical reasons), TS was more likely to involve a subsequent disruption to statin therapy than GS. TS could potentially lead to adverse impacts on patients' outcomes, and should be studied further.

The economic effect of oral linezolid versus intravenous vancomycin in the outpatient setting: the payer perspective.

Oral antibiotic therapy can reduce complications and costs compared with intravenous (IV) therapy. The object of this study was to determine the health economic and resource utilization effects of outpatient treatment with oral linezolid relative to IV vancomycin. Longitudinal claims data from 80 health care plans were used. Patients 18 years and older, who did not have osteomyelitis, with a pharmacy claim for linezolid or vancomycin between January 1, 2002 and March 31, 2004 were eligible. Clinical and resource utilization data were collected for 12 months before and 35 days after treatment. Patients treated with linezolid were matched with controls treated with vancomycin, based on propensity scoring. Direct medical costs paid by health plans were compared. A total of 1,048 matched pairs were identified. Demographic and clinical characteristics were comparable between groups. Patients with linezolid claims had lower resource utilization versus those with vancomycin claims during follow-up, including fewer mean physician office visits (4.1+/-5.7 vs. 8.4+/-13.8 visits; P< .001); lab/diagnostic claims (6.3+/-18.0 vs. 10.4 +/-15.2 claims; P< .001); pharmacy claims (7.3+/-8.1 vs. 13.6+/-17.4 claims; P< .001); emergency room visits (9.7% vs. 13.9%; P= .003) and hospitalization (15.3% vs. 19.1%; P= .024). Patients receiving vancomycin were more likely to be hospitalized or have an emergency room visit than patients receiving linezolid. Mean total adjusted cost was 4,707 dollars less for linezolid compared with vancomycin (8,401dollars vs. 13,108 dollars; P< .001). Similar trends were observed for patients matched based on complicated skin and soft tissue infection diagnosis. Outpatient treatment with oral linezolid was associated with significantly lower resource utilization and total medical costs compared with IV vancomycin.

Retrospective evaluation of outcomes in patients with overactive bladder receiving tolterodine versus oxybutynin.

PURPOSE: The frequency, relative risk, resource utilization, and costs related to comorbidities associated with overactive bladder (OAB) were studied. METHODS: A retrospective analysis of patients with OAB who initiated treatment with tolterodine extended release (ER), oxybutynin ER, or oxybutynin immediate release (IR) between January 2001 and December 2002 was conducted to evaluate the frequency, relative risk, resource utilization, and costs related to three specific comorbidities associated with OAB: urinary tract infections (UTIs), depression, and fracture. Two patient cohorts (tolterodine ER versus oxybutynin ER and tolterodine ER versus oxybutynin IR) were matched on a 1:1 basis according to their propensity to receive a prescription for tolterodine ER. RESULTS: The frequency and relative risk of UTIs were significantly lower in the tolterodine ER group than in the oxybutynin ER and oxybutynin IR groups. The relative risk of depression was also lower in the tolterodine ER group than the oxybutynin ER and oxybutynin IR groups; however, the differences were only significant in the tolterodine ER versus oxybutynin IR comparison. The utilization of UTI- and depression-related services and the number of antiinfective and antidepressant prescriptions were significantly lower in the tolterodine ER group than in the oxybutynin ER group. UTI- and depression-related costs were generally lower in the tolterodine ER group than in the oxybutynin ER or oxybutynin IR group. CONCLUSION: Treatment of OAB patients with tolterodine ER was associated with reduced frequency, relative risk, medical and pharmacy resource utilization, and incurred costs related to selected OAB-associated comorbidities compared with treatment with oxybutynin ER or oxybutynin IR.

Economic impact of extended-release tolterodine versus immediate- and extended-release oxybutynin among commercially insured persons with overactive bladder.

OBJECTIVE: To examine levels of persistence and compliance as well as the economic impact of extended-release tolterodine (tolterodine ER) versus immediate- and extended-release oxybutynin (oxybutynin IR or oxybutynin ER) among commercially-insured patients with overactive bladder (OAB). METHODS: Patients with OAB who initiated tolterodine ER, oxybutynin IR, or oxybutynin ER between January 2001 and December 2002 were identified from the PharMetrics Patient-Centric database; the first medication used in this timeframe was used for treatment group assignment (ie, patients were only in 1 group). Exploratory assessment of persistency and compliance was conducted among all treated patients: subjects were matched 1:1 based on the estimated propensity score for tolterodine ER in remaining analyses. Measures included patient characteristics as well as levels of medication, outpatient and inpatient resource utilization, and costs. Primary comparisons were made descriptively; costs were evaluated using generalized linear models with a gamma distribution and log-link function. RESULTS: Compliance did not differ between tolterodine ER (77.4%) and oxybutynin ER (74.3%), but was lower for oxybutynin IR (60.9%). Mean (+/- standard deviation) duration of therapy was higher for tolterodine ER (139 +/- 132 days) versus oxybutynin ER (115 +/- 122) and oxybutynin IR (60 +/- 85). Totals of 7257 and 5936 matched pairs were available for tolterodine ER versus oxybutynin ER and oxybutynin IR comparisons, respectively. The mean age was 54 years in all groups; the majority was women. Utilization of outpatient and inpatient medical services was consistently lower among tolterodine ER patients in both comparisons. Total costs were slightly lower for tolterodine ER versus oxybutynin ER (dollar 8303 +/- dollar 18 802 vs dollar 8862 +/- dollar 18 684) and oxybutynin IR (dollar 9975 +/- dollar 24860 vs dollar 10521 +/- dollar 22 602); differences were significant after multivariate adjustment. CONCLUSIONS: Use of tolterodine ER results in comparable compliance to oxybutynin ER and longer duration of use relative to either form of oxybutynin. In addition, tolterodine ER may be cost-effective relative to oxybutynin IR or oxybutynin ER among commercially-insured persons with OAB.