Corrigendum to: Longitudinal, Nationwide, Cohort Study to Assess Incidence, Outcomes, and Costs Associated With Complicated Urinary Tract Infection.

[This corrects the article DOI: 10.1093/ofid/ofz446.].

Treatment patterns and characteristics of patients with migraine in Japan: A retrospective analysis of health insurance claims data.

OBJECTIVE: To describe treatment patterns of migraine patients in the Japan Medical Data Center (JMDC) database. METHODS: Patients aged ≥18 years with ≥1 inpatient or ≥2 outpatient migraine diagnoses, ≥1 outpatient diagnosis and ≥1 migraine-specific acute treatment (triptan or ergotamine), or ≥2 migraine-specific acute treatments from 1 May 2011 to 30 April 2014 were identified. Patients were required to be enrolled in a health plan for ≥1 year before and after the index date. The first migraine diagnosis or acute treatment defined the index date. Patients were stratified by the migraine treatments observed after the index date (i.e. migraine-specific acute treatment only [AT], prophylactic with or without migraine-specific acute treatment [PT], or no treatment [NT]) and described regarding the first migraine treatment regimen and subsequent treatment patterns during up to 1 year of follow-up. RESULTS: A total of 16,443 patients met the eligibility criteria (9873 AT, 3022 PT, and 3548 NT). AT patients had mean (SD) 10.3 (20.5) acute treatment days during 1-year follow-up, and 81.9% received triptans. When assessing the first migraine treatment regimen during follow-up in PT patients, 29.2% received prophylactic treatment only and 51.7% received both acute and prophylactic treatment. Calcium-channel blockers with or without concomitant triptans (34.4%) were the most common first regimen. Approximately 62.2% discontinued initial prophylactic treatment after an average of 61.2 days (SD = 65.3) of persistent treatment. Among discontinuers, 15.2% reinitiated original treatment and 7.0% switched treatment post-discontinuation within a year, while the remaining patients did not receive prophylactic therapy following discontinuation. CONCLUSIONS: Among Japanese migraine patients, prophylactic use was low and associated with a high rate of discontinuation following a brief treatment period. Many patients reinitiated or switched treatment following discontinuation, while a significant proportion of patients remained discontinued from prophylactic therapy, suggesting a high unmet need.

Costs of herpes zoster complications in older adults: A cohort study of US claims database.

BACKGROUND/OBJECTIVES: Herpes zoster (HZ) incidence increases with age, and the burden of HZ is expected to grow with aging of populations worldwide. We aim to determine the incremental healthcare resource utilization and associated costs of patients with common HZ-related complications other than postherpetic neuralgia (cutaneous, neurologic and ophthalmic) compared to uncomplicated HZ. METHODS: We conducted a retrospective cohort study of commercial health insurance claims covering about 40 million immunocompetent individuals aged ≥50 years at study entry from all over the US, from 2008 to 2013, with follow-up for one year after HZ onset. All-cause healthcare resource utilization and direct healthcare costs were recorded and calculated from six months before until 12 months after HZ onset. The mean costs for HZ patients with complications were compared to the mean costs for patients with uncomplicated HZ. Multivariable regression analyses estimated mean incremental costs adjusted for demographics, comorbidities, type of complication and time period. RESULTS: Over the five-year study period, 22,948 HZ patients (60% women, median age 62 years) who experienced at least one of the selected complications were compared to 213,232 patients (63% women, median age 61 years) with uncomplicated HZ. Overall, the mean annual incremental unadjusted costs for the patients with HZ-related complications were US$4716, ranging from US$2173 for ophthalmic to US$18,323 for neurologic complications. Most of the incremental costs associated with HZ complications were accrued during the first quarter after HZ onset. For each complication type the incremental costs increased with age up to, but not including the oldest group, aged ≥80 years. CONCLUSIONS: Approximately 10% of immunocompetent older patients with HZ develop complications which considerably increase the economic burden of HZ. Vaccination of older adults will offset some of the burden of HZ, including costs associated with HZ-related complications.

Cost of herpes zoster and herpes zoster-related complications among immunocompromised individuals.

Herpes zoster (HZ) is a painful dermatomal rash caused by reactivation of latent varicella-zoster virus. The incidence of HZ is increased for immunocompromised (IC) individuals. The objective of this study is to assess the healthcare costs incurred by IC individuals who develop HZ with or without associated complications. We conducted a retrospective case-control study across the US over a 5-year period, based on health insurance claims data for individuals aged ≥50 years identified as IC by disease or immunosuppressive treatment. A cohort of 30,107 IC individuals who experienced HZ was matched to a cohort of 113,875 IC individuals without HZ. Average all-cause healthcare costs over 18 months were calculated and compared between IC individuals with and without HZ. In addition, the costs of HZ in IC individuals with HZ-related complications were compared to the costs of those with uncomplicated HZ. During the year following HZ onset, IC individuals with HZ had on average total unadjusted costs that were US$3879 higher than the controls. After adjusting costs, controlling for comorbidities and healthcare costs before the onset of HZ, the average annual costs for HZ cases and controls without HZ were similar. HZ-related complications led to increases in average adjusted annual costs compared to uncomplicated HZ ranging from US$612 for eye complications to US$4535 for neurologic complications. In conclusion, in IC individuals, episodes of HZ lead to substantially increased unadjusted annual healthcare costs. HZ-related complications add considerably to adjusted annual healthcare costs compared to uncomplicated HZ.

Analysis of real-world health care costs among immunocompetent patients aged 50 years or older with herpes zoster in the United States.

Few peer-reviewed publications present real-world United States (US) data describing resource utilization and costs associated with herpes zoster (HZ) and postherpetic neuralgia (PHN). The primary objective of this analysis (GSK study identifier: HO-14-14270) was to assess direct costs associated with HZ and PHN in the US using a retrospective managed care insurance claims database. Patients ≥ 50 y at HZ diagnosis were selected. Patients were excluded if they were immunocompromised before diagnosis or received an HZ vaccine at any time. A subsample of patients with PHN was identified. Each patient with HZ was matched to ≤ 4 controls without HZ based on age, sex, and health plan enrollment. Incremental differences in mean HZ-related costs ("incremental costs") were assessed overall and stratified by age. Multivariable regression models controlled for the effect of demographic characteristics, prediagnosis costs, and comorbidity burden on costs using a recycled predictions approach. Overall, 142,519 patients with HZ (9,470 patients [6.6%] had PHN) and 357,907 matched controls without HZ were identified. Resource utilization was greater among patients with HZ than controls. After adjusting for demographic and clinical characteristics, annual incremental health care costs for HZ patients vs. controls were $1,210 for patients aged 50-59 years, $1,629 for those 60-64 years, $1,876 for those 65-69 years, $2,643 for those 70-79 years, and $3,804 for those 80+ years; adjusted annual incremental costs among PHN patients vs. controls were $4,670 for patients 50-59 years, $6,133 for those 60-64 years, $6,451 for those 65-69 years, $8,548 for those 70-79 years, and $11,147 for those 80+ years. HZ is associated with a significant cost burden, which increases with advancing patient age. Vaccination may reduce costs associated with HZ through case avoidance.

Factors associated with inpatient readmission among managed care enrollees with COPD.

OBJECTIVE: To assess factors associated with inpatient readmission among a US managed care population with chronic obstructive pulmonary disease (COPD). BACKGROUND: COPD is often accompanied by intermittent acute exacerbations, which may result in hospitalizations. These exacerbations are often associated with an increased frequency of subsequent exacerbations, which may lead to inpatient readmissions. METHODS: We assessed US managed care claims data for enrollees≥40 years old with an inpatient admission with a primary diagnosis of COPD (ICD-9-CM codes 491.xx, 492.xx or 496.xx) between 1 January 2010 and 31 December 2013 (discharge date of first observed inpatient admission defined the "index date"). Patients were required to be continuously enrolled for ≥12 months before the index date. Two non-mutually exclusive cohorts were analyzed: (1) patients with ≥30 days of post-index date continuous enrollment (to evaluate 30-day readmission) and (2) patients with ≥90 days of post-index date continuous enrollment (to evaluate 90-day readmission). Logistic regression evaluated the association between patient characteristics and risk of 30- and 90-day COPD-related and all-cause readmission. RESULTS: After applying selection criteria, 140,981 patients had ≥30 days of enrollment post-index date, and 123,545 patients had ≥90 days of enrollment post-index date. Within 30 days, nearly 20% of patients had an all-cause readmission and 7% had a COPD-related readmission. Within 90 days, 28% had an all-cause readmission and 12% had a COPD-related readmission. Logistic regression indicated that longer length of stay, older age, greater comorbidity burden, specific comorbidities and COPD complexity were associated with significantly greater odds of COPD-related 30- and 90-day readmission. Results for all-cause readmission were generally similar. CONCLUSIONS: Many of the factors associated with inpatient readmission documented here can be ascertained at discharge and may be used to inform discharge plans, with the end goal of improving patient outcomes, including reducing the risk of readmission.

The high-cost, type 2 diabetes mellitus patient: an analysis of managed care administrative data.

BACKGROUND: Type 2 diabetes mellitus (T2DM) affects 25.8 million individuals in the United States and exerts a substantial economic burden on patients, health care systems, and society. Few studies have categorized costs and resource use at the patient level. The goals of this study were to assess predictors of being a high-cost (HC) patient and compare HC T2DM patients with not high-cost (NHC) T2DM patients. METHODS: Using managed care administrative claims data, patients with two or more T2DM diagnoses between 2005 and 2010 were selected. Patients were followed for 1 year after their first observed T2DM diagnosis; patients not continuously enrolled during this period were excluded from the study. Study measures included annual health care expenditures by component (i.e., inpatient, outpatient, pharmacy, total). Patients accruing total costs in the top 10% of the overall cost distribution (i.e., patients with costs > $20,528) were classified as HC a priori; all other patients were considered NHC. To assess predictors of being HC, a logistic regression model was estimated, accounting for demographics; underlying comorbidity burden (using the Charlson Comorbidity Index [CCI] score); diagnoses of renal impairment, obesity, or hypertension; and receipt of insulin, oral antidiabetics only, or no antidiabetics. RESULTS: A total of 1,720,041 patients met the inclusion criteria; 172,004 were HC. The mean (SD) CCI score for HC patients was 4.3 (3.0) versus 2.1 (1.7) for NHC patients. Mean (SD; upper 95% confidence interval-lower 95% confidence interval) annual per-patient costs were $56,468 ($65,604; $56,778-$56,157) among HC patients and $4,674 ($4,504; $4,695-$4,652) among NHC patients. Inpatient care and pharmacy costs were higher for HC patients than for NHC patients. The strongest predictor of being an HC patient was having a CCI score of 2 or greater (odds ratio [OR] = 4.896), followed by a diagnosis of obesity (OR = 2.106), renal impairment (OR = 2.368), and insulin use (OR = 2.098). CONCLUSIONS: High-cost T2DM patients accrue approximately $52,000 more in total annual health care costs than not high-cost T2DM patients. Patients were significantly more likely to be high-cost if they had comorbid conditions, a diagnosis of obesity, or used insulin.

Association between daily antiretroviral pill burden and treatment adherence, hospitalisation risk, and other healthcare utilisation and costs in a US medicaid population with HIV.

OBJECTIVES: Lower pill burden leads to improved antiretroviral therapy (ART) adherence among HIV patients. Simpler dosing regimens have not been widely explored in real-world populations. We retrospectively assessed ART adherence, all-cause hospitalisation risk and costs, and other healthcare utilisation and costs in Medicaid enrollees with HIV treated with ART as a once-daily single-tablet regimen (STR) or two or more pills per day (2+PPD). DESIGN: Patients with an HIV diagnosis from 2005 to 2009 receiving complete ART (ie, two nucleoside/nucleotide reverse transcriptase inhibitors plus a third agent) for ≥60 days as STR or 2+PPD were selected and followed until the first of (1) discontinuation of the complete ART, (2) loss of enrolment or (3) end of database. Adherence was measured using the medication possession ratio. Monthly all-cause healthcare utilisation and costs were observed from regimen initiation until follow-up end. RESULTS: Of the 7381 patients who met inclusion criteria, 1797 were treated with STR and 5584 with 2+PPD. STR patients were significantly more likely to reach 95% adherence and had fewer hospitalisations than 2+PPD patients (both p<0.01). STR patients had mean (SD) total monthly costs of $2959 ($4962); 2+PPD patients had $3544 ($5811; p<0.001). Hospital costs accounted for 53.8% and pharmacy costs accounted for 32.5% of this difference. Multivariate analyses found that STR led to a 23% reduction in hospitalisations and a 17% reduction in overall healthcare costs. ART adherence appears to be a key mechanism mediating hospitalisation risk, as patients with ≥95% adherence (regardless of regimen type) had a lower hospitalisation rate compared with <95% adherence. CONCLUSIONS: While it was expected that STR patients would have lower pharmacy costs, we also found that STR patients had fewer hospitalisations and lower hospital costs than 2+PPD patients, resulting in significantly lower total healthcare costs for STR patients.

Adherence to antiretroviral treatment and correlation with risk of hospitalization among commercially insured HIV patients in the United States.

PURPOSE: A lower daily pill burden may improve adherence to antiretroviral treatment (ART) and clinical outcomes in patients with human immunodeficiency virus (HIV). This study assessed differences in adherence using the number of pills taken per day, and evaluated how adherence correlated with hospitalization. METHODOLOGY: Commercially insured patients in the LifeLink database with an HIV diagnosis (International Classification of Diseases, 9th Revision, Clinical Modification code 042.xx) between 6/1/2006 and 12/31/2008 and receipt of a complete ART regimen were selected for inclusion. Patients were grouped according to their daily pill count and remained on ART for at least 60 days. Outcomes included adherence and rates of hospitalization. Adherence was measured as the proportion of days between the start and end of the regimen in which the patient maintained supply of all initiated ART components. Logistic regressions assessed the relationship between pills per day, adherence, and hospitalization, controlling for demographics, comorbidities, and ART-naïve (vs. experienced) status. RESULTS: 7,073 patients met the study inclusion criteria, and 33.4%, 5.8%, and 60.8% received an ART regimen comprising one, two, or three or more pills per day, respectively. Regression analysis showed patients receiving a single pill per day were significantly more likely to reach a 95% adherence threshold versus patients receiving three or more pills per day (odds ratio [OR] = 1.59; P<0.001). Regardless of the number of pills received per day, patients were over 40% less likely to have a hospitalization if they were adherent to therapy (OR = 0.57; P<0.001). Patients receiving a single pill per day were 24% less likely to have a hospitalization versus patients receiving three or more pills per day (OR = 0.76; P = 0.003). CONCLUSIONS: ART consisting of a single pill per day was associated with significantly better adherence and lower risk of hospitalization in patients with HIV compared to patients receiving three or more pills per day.

The economic costs to United States hospitals of invasive fungal infections in transplant patients.

BACKGROUND: Patients with a solid organ transplant (SOTs) and hematopoietic stem cell or bone marrow transplants (HSC/BMTs) are at risk of contracting invasive fungal infections (IFIs). Data on the economic burden of IFIs in the United States are sparse. METHODS: We conducted a retrospective matched cohort study using the 2004-2005 Healthcare Cost and Utilization Project Nationwide Inpatient Sample. The IFI cohort included patients with ICD-9-CM codes indicating a transplant procedure and an IFI. Matched controls (transplant recipients without an IFI) were chosen based on age (10 year categories), sex, region, hospital type, year, and transplant type. Mortality, length of stay, and costs were reported overall, by transplant type, and by type of mycosis. RESULTS: Nine thousand eight hundred ninety-six patients underwent SOT, and 4661 underwent HSC/BMT. Of these, 80 (0.8%) SOT and 111 (2.4%) HSC/BMT patients had an IFI. Mean age was 41.8 years (SOT) and 37.8 years (HSC/BMT). Aspergillosis was the most common infection. Patients with an IFI had a 5-fold increase in mortality, an additional 19.2 hospital days, and $55,400 in excess costs compared with patients without an IFI. Excess mortality, length of stay, and costs varied by type of transplant and mycosis. CONCLUSION: The clinical and economic burden of IFIs in transplant recipients may be high.

Medication adherence and hospitalization among patients with schizophrenia treated with antipsychotics.

OBJECTIVE: This analysis assessed rates of medication adherence and predictors of nonadherence and hospitalization among patients treated with long-acting injectable and oral antipsychotic therapies. METHODS: Data were from a retrospective analysis of Florida Medicaid recipients with schizophrenic disorder (ICD-9-CM code 295.XX) who received a prescription for an antipsychotic between July 1, 2004, and June 30, 2005. Patients were required to have filled one additional antipsychotic prescription during follow-up. Adherence measures included medication possession ratio (MPR), medication persistence, medication consistency, and maximum gap in treatment. Multivariate logistic regression models identified predictors of nonadherence and hospitalization. RESULTS: Patients were considered adherent if they had an MPR ≥ .8. A total of 12,032 patients met selection criteria. The mean ± SD MPR was .79 ± .23, medication persistence was 94.1% ± 16.4%, medication consistency was 83.3% ± 16.4%, and the maximum gap in treatment was 29.7 ± 41.4 days. Thirty-seven percent of patients were hospitalized for any cause, and 32% had a psychiatric hospitalization. Predictors of nonadherence included newly starting treatment; younger age; a substance abuse diagnosis; use of a mood stabilizer, antidepressant, anxiolytic, or anticholinergic; and receipt of long-acting first-generation antipsychotics. Receipt of long-acting second-generation therapy or receipt of both first- and second-generation medications was associated with lower likelihood of nonadherence. Predictors of hospitalization risk included a diagnosis of other psychoses or substance abuse, anticholinergic use, and nonadherence to therapy. CONCLUSIONS: Results document rates of antipsychotic adherence and predictors of nonadherence and hospitalization. Findings may be useful to health plan administrators, formulary decision makers, and physicians.

Inpatient treatment patterns, outcomes, and costs of skin and skin structure infections because of Staphylococcus aureus.

BACKGROUND: Staphylococcus aureus (SA) is a common bacterial pathogen in skin and skin structure infections (SSSIs). Limited data exist on hospital treatment patterns and costs for SA-SSSIs. METHODS: This retrospective analysis examined the lengths of stay, treatment patterns, and costs of hospitalized patients with an SA-SSSI diagnosis using a nationally representative inpatient database. Patients were selected if they had an ICD-9-CM diagnosis of an SSSI with SA noted between January 2005 and June 2006, received a study antibiotic (ie, intravenous [IV] vancomycin, IV or oral linezolid, and IV daptomycin), and were not in the intensive care unit before receiving a study antibiotic. Generalized linear models assessed predictors of length of stay and costs. Costs are expressed in 2005 US dollars. RESULTS: Thirteen thousand four hundred thirty-three patients met the selection criteria and mean (+/-SD) age was 48.2 (+/-18.3) years. Forty percent of patients received a nonstudy antibiotic before receiving their first study antibiotic. Ninety-five percent were prescribed vancomycin as their first study antibiotic. Study antibiotics were administered for an average of 4.3 days, and 8% of patients switched study antibiotics. Nineteen percent of patients receiving IV linezolid stepped down to oral linezolid. Mean (+/-SD) lengths of hospital stay and costs were 6.1 (+/-6.0) days and $6830 (+/-$7100). In-hospital mortality, switching antibiotics, and diagnoses of selected complications or comorbidities were associated with increased lengths of stay and costs. Younger age, location outside the Northeast, and use of oral linezolid were associated with lower lengths of stay and costs. CONCLUSION: The costs of treating inpatient SA-SSSIs are substantial and vary by patient demographics and treatment characteristics.

Mortality, length of hospitalization, and costs associated with invasive fungal infections in high-risk patients.

PURPOSE: The mortality, length of hospitalization, and costs associated with invasive fungal infections (IFIs) in hospitalized patients were studied. METHODS: This retrospective database study used data from the 2004 Healthcare Cost and Utilization Project Nationwide In-patient Sample. Patients were selected for inclusion based on diagnostic codes corresponding to an IFI. A control group was matched to the IFI group based on high-risk conditions (i.e., cancer, infection with human immunodeficiency virus, chronic obstructive pulmonary disease, diabetes mellitus, and solid-organ, hematopoietic stem cell, or bone marrow transplant), age, sex, and hospital region and teaching status. Excess mortality, length of hospital stay, and costs were estimated as the differences between the IFI and control groups. RESULTS: A total of 11,881 patients were identified with a discharge diagnosis of an IFI who could be matched to a control. Frequent infections included candidiasis (40.2%), other mycoses (36.3%), and aspergillosis (16.4%). Patients with IFIs had a significantly higher mortality rate (15% versus 5%), mean +/- S.E. length of stay (18.7 +/- 0.4 days versus 7.3 +/- 0.1 days), and mean +/- S.E. costs ($44,726 +/- $1,255 versus $15,445 +/- $404) (p < 0.001 for all comparisons) than did patients without IFIs. The burden of IFIs varied by high-risk condition (highest for transplant recipients and patients with cancer) and type of infection (highest for candidiasis, zygomycosis, and aspergillosis). CONCLUSION: Examination of a large database showed that, compared with high-risk patients without IFIs, those with IFIs had higher mortality, a longer hospital stay, and higher costs associated with their hospitalization.