Effectiveness and Safety of Oral Anticoagulants Among Nonvalvular Atrial Fibrillation Patients.

Background and Purpose- This ARISTOPHANES study (Anticoagulants for Reduction in Stroke: Observational Pooled Analysis on Health Outcomes and Experience of Patients) used multiple data sources to compare stroke/systemic embolism (SE) and major bleeding (MB) among a large number of nonvalvular atrial fibrillation patients on non-vitamin K antagonist oral anticoagulants (NOACs) or warfarin. Methods- A retrospective observational study of nonvalvular atrial fibrillation patients initiating apixaban, dabigatran, rivaroxaban, or warfarin from January 1, 2013, to September 30, 2015, was conducted pooling Centers for Medicare and Medicaid Services Medicare data and 4 US commercial claims databases. After 1:1 NOAC-warfarin and NOAC-NOAC propensity score matching in each database, the resulting patient records were pooled. Cox models were used to evaluate the risk of stroke/SE and MB across matched cohorts. Results- A total of 285 292 patients were included in the 6 matched cohorts: 57 929 apixaban-warfarin, 26 838 dabigatran-warfarin, 83 007 rivaroxaban-warfarin, 27 096 apixaban-dabigatran, 62 619 apixaban-rivaroxaban, and 27 538 dabigatran-rivaroxaban patient pairs. Apixaban (hazard ratio [HR], 0.61; 95% CI, 0.54-0.69), dabigatran (HR, 0.80; 95% CI, 0.68-0.94), and rivaroxaban (HR, 0.75; 95% CI, 0.69-0.82) were associated with lower rates of stroke/SE compared with warfarin. Apixaban (HR, 0.58; 95% CI, 0.54-0.62) and dabigatran (HR, 0.73; 95% CI, 0.66-0.81) had lower rates of MB, and rivaroxaban (HR, 1.07; 95% CI, 1.02-1.13) had a higher rate of MB compared with warfarin. Differences exist in rates of stroke/SE and MB across NOACs. Conclusions- In this largest observational study to date on NOACs and warfarin, the NOACs had lower rates of stroke/SE and variable comparative rates of MB versus warfarin. The findings from this study may help inform the discussion on benefit and risk in the shared decision-making process for stroke prevention between healthcare providers and nonvalvular atrial fibrillation patients. Clinical Trial Registration- URL: https://www.clinicaltrials.gov/ . Unique identifier: NCT03087487.

Major bleeding risk among non-valvular atrial fibrillation patients initiated on apixaban, dabigatran, rivaroxaban or warfarin: a "real-world" observational study in the United States.

BACKGROUND: Limited data are available about the real-world safety of non-vitamin K antagonist oral anticoagulants (NOACs). OBJECTIVES: To compare the major bleeding risk among newly anticoagulated non-valvular atrial fibrillation (NVAF) patients initiating apixaban, warfarin, dabigatran or rivaroxaban in the United States. METHODS AND RESULTS: A retrospective cohort study was conducted to compare the major bleeding risk among newly anticoagulated NVAF patients initiating warfarin, apixaban, dabigatran or rivaroxaban. The study used the Truven MarketScan(®) Commercial & Medicare supplemental US database from 1 January 2013 through 31 December 2013. Major bleeding was defined as bleeding requiring hospitalisation. Cox model estimated hazard ratios (HRs) of major bleeding were adjusted for age, gender, baseline comorbidities and co-medications. Among 29 338 newly anticoagulated NVAF patients, 2402 (8.19%) were on apixaban; 4173 (14.22%) on dabigatran; 10 050 (34.26%) on rivaroxaban; and 12 713 (43.33%) on warfarin. After adjusting for baseline characteristics, initiation on warfarin [adjusted HR (aHR): 1.93, 95% confidence interval (CI): 1.12-3.33, P=.018] or rivaroxaban (aHR: 2.19, 95% CI: 1.26-3.79, P=.005) had significantly greater risk of major bleeding vs apixaban. Dabigatran initiation (aHR: 1.71, 95% CI: 0.94-3.10, P=.079) had a non-significant major bleeding risk vs apixaban. When compared with warfarin, apixaban (aHR: 0.52, 95% CI: 0.30-0.89, P=.018) had significantly lower major bleeding risk. Patients initiating rivaroxaban (aHR: 1.13, 95% CI: 0.91-1.41, P=.262) or dabigatran (aHR: 0.88, 95% CI: 0.64-1.21, P=.446) had a non-significant major bleeding risk vs warfarin. CONCLUSION: Among newly anticoagulated NVAF patients in the real-world setting, initiation with rivaroxaban or warfarin was associated with a significantly greater risk of major bleeding compared with initiation on apixaban. When compared with warfarin, initiation with apixaban was associated with significantly lower risk of major bleeding. Additional observational studies are required to confirm these findings.

The estimated incidence of pertussis in people aged 50 years old in the United States, 2006-2010.

BACKGROUND: Pertussis is believed to be widely underreported and under-recognized, particularly among adults. The aim of this study was to estimate the incidence of private practitioner-attended cough illness that could be attributed to Bordetella pertussis in adults aged ≥50 years in the US. METHODS: Multiple linear regressions were employed to estimate the overall incidence of pertussis. Data were extracted from IMS' private practice database of longitudinal, patient-level claims and IMS' commercial laboratory database during 4/1/2006-12/31/2010. Patients were ≥50 years old and had ≥1 ICD-9-CM claim for cough illness relating to pertussis, cough, or acute bronchitis. Pertussis positive laboratory tests, seasonal and secular variables were used for estimating the B. pertussis attributable fraction of cough illness. RESULTS: During the study period, there were 20.7 million cases of cough illness among people aged 50-64 and 27.5 million cases among those ≥65; of which the model attributed 2.5 and 1.7 %, respectively, to B. pertussis. The estimated incidences of cough illness attributed to B. pertussis during the study period were on average 202 and 257/100,000 among people aged 50-64 and ≥65 years, respectively, and increased over the years in both age groups. Depending on the year, estimated pertussis incidences were 42 to 105 times higher than medically attended ones in the same database. CONCLUSIONS: These findings indicate that the B. pertussis disease incidence in adults aged ≥50 years is significantly higher than generally estimated. Additional research regarding pertussis reporting and diagnosis in the adult populations is needed to validate these findings.

Understanding differences between what alternate propensity score methods estimate.

BACKGROUND: Many approaches to propensity score methods are used in the applied health economics and outcomes research literature. Often this creates confusion when different approaches produce different results for the same data. OBJECTIVE: To present a conceptual overview based on a potential outcomes framework to demonstrate how more than 1 mean treatment effect parameter can be estimated using the propensity score methods and how the selection of appropriate methods should align with the scientific questions. METHODS: We highlight that more than 1 mean treatment effect parameter can be estimated using the propensity score methods. Using the potential outcomes framework and alternate data-generating processes, we discuss under what assumptions different mean treatment effect parameter estimates are supposed to vary. We tie these discussions with propensity score methods to show that different approaches may estimate different parameters. We illustrate these methods using a case study of the comparative effectiveness of apixaban vs warfarin on the likelihood of stroke among patients with a prior diagnosis of atrial fibrillation. RESULTS: Different mean treatment effect parameters take on different values when treatment effects are heterogeneous. We show that traditional propensity score approaches, such as blocking, weighting, matching, or doubly robust, can estimate different mean treatment effect parameters. Therefore, they may not produce the same results even when applied to the same data using the same covariates. We found significant differences in our case study estimates of mean treatment effect parameters. Still, once a mean treatment effect parameter is targeted, estimates across different methods are not different. This highlights the importance of first selecting the target parameter for analysis by aligning the interpretation of the target parameter with the scientific questions and then selecting the specific method to estimate this target parameter. CONCLUSIONS: We present a conceptual overview of propensity score methods in health economics and outcomes research from a potential outcomes framework. We hope these discussions will help applied researchers choose appropriate propensity score approaches for their analysis. DISCLOSURES: Dr Unuigbe's time was supported through an unrestricted postdoctoral fellowship from Pfizer to the University of Washington, Seattle.

The budget impact of introducing the OMNI® surgical system to a United States health plan for managing mild-to-moderate primary open-angle glaucoma.

OBJECTIVES: Minimally invasive glaucoma surgery devices fill an unmet need in the treatment paradigm between topical intraocular pressure medicines and more invasive filtration procedures. This study evaluated the adoption of The OMNI® Surgical System with or without cataract surgery in primary open-angle glaucoma patients. METHODS: A budget impact analysis estimated costs before and after adoption of OMNI® to a hypothetical US health plan with 1 million Medicare-covered lives over two years. Model input data were derived from published sources and development of the model included primary research with key opinion leaders and payers. The model compared total annual direct costs for OMNI® versus other treatment options (medications, other minimally invasive surgical procedures, selective laser trabeculoplasty) to calculate budget impact. A one-way sensitivity analysis was conducted to assess parameter uncertainty. RESULTS: Increased adoption of OMNI® resulted in budget neutrality over the two years with a decrease in total costs of $35,362. Per member per month incremental costs were $0.00 when used without cataract surgery and yielded cost savings of -$0.01 when used with cataract surgery. Sensitivity analysis confirmed model robustness and identified surgical center fee variability as a key driver of costs. CONCLUSION: OMNI® is budgetary efficient from a US payer perspective.

Clinical and Economic Outcomes Among Nonvalvular Atrial Fibrillation Patients With Coronary Artery Disease and/or Peripheral Artery Disease.

To address literature gaps on treatment with real-world evidence, this study compared effectiveness, safety, and cost outcomes in NVAF patients with coronary or peripheral artery disease (CAD, PAD) prescribed apixaban versus other oral anticoagulants. NVAF patients aged ≥65 years co-diagnosed with CAD/PAD initiating warfarin, apixaban, dabigatran, or rivaroxaban were selected from the US Medicare population (January 1, 2013 to September 30, 2015). Propensity score matching was used to match apixaban versus warfarin, dabigatran, and rivaroxaban cohorts. Cox models were used to evaluate the risk of stroke/systemic embolism (SE), major bleeding (MB), all-cause mortality, and a composite of stroke/myocardial infarction/all-cause mortality. Generalized linear and two-part models were used to compare stroke/SE, MB, and all-cause costs between cohorts. A total of 33,269 warfarin-apixaban, 9,335 dabigatran-apixaban, and 33,633 rivaroxaban-apixaban pairs were identified after matching. Compared with apixaban, stroke/SE risk was higher in warfarin (hazard ratio [HR]: 1.93; 95% confidence interval [CI]: 1.61 to 2.31), dabigatran (HR: 1.69; 95% CI: 1.18 to 2.43), and rivaroxaban (HR: 1.24; 95% CI: 1.01 to 1.51) patients. MB risk was higher in warfarin (HR: 1.67; 95% CI: 1.52 to 1.83), dabigatran (HR: 1.37; 95% CI: 1.13 to 1.68), and rivaroxaban (HR: 1.87; 95% CI: 1.71 to 2.05) patients vs apixaban. Stroke/SE- and MB-related medical costs per-patient per-month were higher in warfarin, dabigatran, and rivaroxaban patients versus apixaban. Total all-cause health care costs were higher in warfarin and rivaroxaban patients compared with apixaban patients. In conclusion, compared with apixaban, patients on dabigatran, rivaroxaban, or warfarin had a higher risk of stroke/SE, MB, and event-related costs.

Equity in access to health care in Italy: a disease-based approach.

BACKGROUND: Equitable access to health care is a core objective of the Italian health care system. Despite having achieved universal coverage for a fairly comprehensive set of health services for decades, there is still evidence of inequities systematically associated with income. METHOD: Income-related inequity indices were estimated for the probability of general practitioner (GP), specialist, inpatient care and also emergency care using a variety of need indicators. The data used were the Multiscopo survey, 2000 matched with the European Community Household Panel survey for Italy. The contribution of regional inequality was also estimated. Horizontal inequity indices for health care utilization measures were computed separately for people reporting hypertension, arthritis, tumour and heart disease. RESULTS: Significant pro-rich income related inequity was found for GP, specialist and emergency care, no inequity was found for inpatient care. The disease approach showed statistically significant inequity in the probability of specialist care in three of the four chronic conditions analysed, and pro-poor inequity in GP care for all conditions. Inequity was mainly caused by income and regional variations. CONCLUSIONS: By reducing regional variation it would be possible to significantly reduce the pro-rich inequity in GP, specialist and emergency care. For specialist care inequity was found for the overall adult population and also among people with serious chronic conditions, and was caused not only by income and regional variation, but also by educational attainment and insurance.

The socio-economic determinants of the health status of Roma in comparison with non-Roma in Bulgaria, Hungary and Romania.

BACKGROUNDS: Roma people from Central and Eastern Europe suffer some of the worst health conditions in the industrialized world. This article aims at identifying the determinants of health status among Roma in comparison with non-Roma in Bulgaria, Romania and Hungary. METHODS: Non-linear models were estimated for three different health indicators: self-reported health compared with the previous year, probability of reporting chronic conditions and feeling threatened by illness because of sanitary and hygienic circumstances. Ethnic origin differentiated by Roma, national population and other ethnic minorities is self-reported. The data used are from a unique data set provided by the United Nations Development Programme household survey on Roma and populations living in their close proximity for 2004. Sample sizes are 2536 for Bulgaria, 2640 for Hungary and 3292 for Romania. RESULTS: After controlling for demographic variables the Roma were significantly more likely to report worse health in any indicator than the non-Roma everywhere. However, after including socio-economic variables, Roma had a significantly higher probability of reporting chronic conditions only in Romania. For the probability of feeling threatened by illness because of unhygienic circumstances, being Roma was a main determinant in Hungary and Romania, but not in Bulgaria. The results for self-reported health were inconclusive. CONCLUSIONS: While these results in part support the development of health policies targeting Roma, the finding that poorly educated and less wealthy people, as well as other ethnic minorities also experience health inequalities suggests that broader multisectoral policies are needed in the countries studied.

Corrigendum to "Effectiveness and Safety of Oral Anticoagulants in Adults with Non-valvular Atrial Fibrillation Patients and Concomitant Coronary/Peripheral Artery Disease" American Journal of Medicine 131:09 (2018): 1074-1085.e4.

RESULTS: There were 33,269 apixaban-warfarin, 9,345 dabigatran-warfarin, and 42,156 rivaroxaban-warfarin matched pairs, with a median follow-up of 4-5 months. Compared with warfarin, apixaban was associated with lower rates of stroke/systemic embolism (hazard ratio [HR] 0.52; 95% confidence interval [95% CI], 0.43-0.62), major bleeding (HR 0.60; 95% CI, 0.55-0.66) and stroke/myocardial infarction/all-cause mortality (HR 0.70; 95%CI, 0.66-0.74); dabigatran was associated with lower rates of major bleeding (HR: 0.73; 95% CI, 0.62-0.85); dabigatran and rivaroxaban were associated with lower rates of stroke/myocardial infarction/all-cause mortality (HR 0.77; 95% CI, 0.69-0.86 and HR 0.81; 95% CI, 0.77-0.85, respectively). Rivaroxaban was associated with a lower rate of stroke/systemic embolism (HR 0.61; 95% CI, 0.53-0.71) and a higher rate of major bleeding (HR 1.10; 95%CI, 1.03-1.18) versus warfarin.

Measuring socioeconomic differences in use of health care services by wealth versus by income.

OBJECTIVES: We compared the extent of socioeconomic differences in use of health care services based on wealth (i.e., accumulated assets) as the socioeconomic ranking variable with the extent of differences based on income to explore the sensitivity of the estimates of equity to the choice of the socioeconomic indicator. METHODS: We used data from the Health and Retirement Study in the United States and the Survey of Health, Ageing, and Retirement in Europe to estimate levels of income- and wealth-related disparity in use of physician and dental services among adults 50 or older in 12 countries. RESULTS: We found socioeconomic differences in use of physician services after standardizing for need in about half of the countries studied. No consistent pattern in levels of disparity measured by wealth versus those measured by income was found. However, the rich were significantly more likely to use dental services in all countries. Wealth-related differences in dental service use were consistently higher than were income-related differences. CONCLUSIONS: We found some support for wealth as a more sensitive indicator of socioeconomic status among older adults than was income. Wealth may thus allow more accurate measurements of socioeconomic differences in use of health care services for this population.

Real-world comparison of bleeding risks among non-valvular atrial fibrillation patients prescribed apixaban, dabigatran, or rivaroxaban.

Limited real-world data are available regarding the comparative safety of non-vitamin K antagonist oral anticoagulants (NOACs). The objective of this retrospective claims observational cohort study was to compare the risk of bleeding among non-valvular atrial fibrillation (NVAF) patients prescribed apixaban, dabigatran, or rivaroxaban. NVAF patients aged ≥18 years with a 1-year baseline period were included if they were new initiators of NOACs or switched from warfarin to a NOAC. Cox proportional hazards modelling was used to estimate the adjusted hazard ratios of any bleeding, clinically relevant non-major (CRNM) bleeding, and major inpatient bleeding within 6 months of treatment initiation for rivaroxaban and dabigatran compared to apixaban. Among 60,227 eligible patients, 8,785 were prescribed apixaban, 20,963 dabigatran, and 30,529 rivaroxaban. Compared to dabigatran or rivaroxaban patients, apixaban patients were more likely to have greater proportions of baseline comorbidities and higher CHA2DS2-VASc and HAS-BLED scores. After adjusting for baseline clinical and demographic characteristics, patients prescribed rivaroxaban were more likely to experience any bleeding (HR: 1.35, 95% confidence interval [CI]: 1.26-1.45), CRNM bleeding (HR: 1.38, 95% CI: 1.27-1.49), and major inpatient bleeding (HR: 1.43, 95% CI: 1.17-1.74), compared to patients prescribed apixaban. Dabigatran patients had similar bleeding risks as apixaban patients. In conclusion, NVAF patients treated with rivaroxaban appeared to have an increased risk of any bleeding, CRNM bleeding, and major inpatient bleeding, compared to apixaban patients. There was no significant difference in any bleeding, CRNM bleeding, or inpatient major bleeding risks between patients treated with dabigatran and apixaban.

Discontinuation risk comparison among 'real-world' newly anticoagulated atrial fibrillation patients: Apixaban, warfarin, dabigatran, or rivaroxaban.

Discontinuation of oral anticoagulants may expose non-valvular atrial fibrillation (NVAF) patients to an increased risk of stroke. This study describes the real-world discontinuation rates and compared the risk of drug discontinuation among NVAF patients initiating apixaban, warfarin, dabigatran, or rivaroxaban. This retrospective cohort study evaluated newly-anticoagulated NVAF patients in the MarketScan® data population from 01/01/2012 through 12/31/2014. Discontinuation was defined as a lack of subsequent prescription of the index drug within 30 days after the last supply day of the last prescription. A Cox model was used to estimate the hazard ratio (HR) of discontinuation, adjusted for age, sex, and comorbidities. Among 45,361 eligible NVAF patients, 15,461 (34.1%) initiated warfarin; 7,438 (16.4%) apixaban; 4,661 (10.3%) dabigatran; and 17,801 (39.2%) initiated rivaroxaban treatment. Compared to warfarin, patients who initiated dabigatran (adjusted HR [aHR]: 0.84, 95% confidence interval [CI]: 0.80-0.87, P<0.001), rivaroxaban (aHR: 0.70, 95% CI: 0.68-0.73, P<0.001), or apixaban (aHR: 0.57, 95% CI: 0.55-0.60, P<0.001) were 16%, 30%, and 43% less likely to discontinue treatment, respectively. When compared to apixaban, patients who initiated dabigatran (aHR: 1.46, 95% CI: 1.38-1.54, P<0.001) or rivaroxaban (aHR: 1.23, 95% CI: 1.17-1.28, P<0.001) were more likely to discontinue treatment. Among newly-anticoagulated NVAF patients in the real-world setting, initiation on rivaroxaban, dabigatran, or apixaban was associated with a significantly lower risk of discontinuation compared to warfarin. When compared to apixaban, patients who initiated treatment with warfarin, dabigatran, or rivaroxaban were more likely to discontinue treatment.

Effectiveness and Safety of Anticoagulants in Adults with Non-valvular Atrial Fibrillation and Concomitant Coronary/Peripheral Artery Disease.

BACKGROUND: Direct oral anticoagulants (DOAC) are at least non-inferior to warfarin in efficacy and safety among patients with nonvalvular atrial fibrillation. Limited evidence is available regarding outcomes for nonvalvular atrial fibrillation patients with coronary/peripheral artery disease. METHODS: Non-valvular atrial fibrillation patients aged ≥65 years diagnosed with coronary/peripheral artery disease in the US Medicare population, newly initiating DOACs (apixaban, rivaroxaban, dabigatran) or warfarin were selected from January 1, 2013 to September 30, 2015. Propensity score matching was used to compare DOACs vs warfarin. Cox proportional hazards models were used to estimate the risk of stroke/systemic embolism, major bleeding, and composite of stroke/myocardial infarction/all-cause mortality. RESULTS: There were 15,527 apixaban-warfarin, 6,962 dabigatran-warfarin, and 25,903 rivaroxaban-warfarin-matched pairs, with a mean follow-up of 5-6 months. Compared with warfarin, apixaban was associated with lower rates of stroke/systemic embolism (hazard ratio [HR] 0.48; 95% confidence interval [CI], 0.37-0.62), major bleeding (HR 0.66; 95% CI, 0.58-0.75), and stroke/myocardial infarction/all-cause mortality (HR 0.63; 95% CI, 0.58-0.69); dabigatran and rivaroxaban were associated with lower rates of stroke/myocardial infarction/all-cause mortality (HR 0.79; 95% CI, 0.70-0.90 and HR 0.87; 95% CI, 0.81-0.92, respectively). Rivaroxaban was associated with a lower rate of stroke/systemic embolism (HR 0.72; 95% CI, 0.60-0.89) and a higher rate of major bleeding (HR 1.14; 95% CI, 1.05-1.23) vs warfarin. CONCLUSIONS: All DOACs were associated with lower stroke/myocardial infarction/all-cause mortality rates compared with warfarin; differences were observed in rates of stroke/systemic embolism and major bleeding. Findings from this observational analysis provide important insights about oral anticoagulation therapy among non-valvular atrial fibrillation patients with coronary/peripheral artery disease and may help physicians in the decision-making process when treating this high-risk group of patients.

Incidence and Burden of Pertussis Among Infants Less Than 1 Year of Age.

BACKGROUND: Infant-specific pertussis data, especially among neonates, are limited and variable. This study (NCT01890850) provides overall and age-specific pertussis incidence and associated health care utilization and costs among commercially insured infants in the US. METHODS: Nearly 1.2 million infants born from 2005 to 2010 with commercial health plan coverage were followed during their first 12 months of life. Pertussis cases were identified from medical claims (International Classification of Diseases, 9th revision, Clinical Modification code: 033.0, 033.9, 484.3), and incidence rates were calculated. Each pertussis case was then matched to 10 comparators, so pertussis-related health care utilization and costs before and after the index date could be assessed. RESULTS: The overall pertussis incidence rate among infants <12 months of age was 117.7/100,000 person-years; infants 3 months of age had the highest incidence rate (247.7/100,000 person-years). Infants diagnosed with pertussis were significantly more likely to have prior diagnoses of upper respiratory infection, cough and wheezing-related illnesses than comparators (P < 0.001). Pertussis cases were more likely to be hospitalized within 14 days after the index date (31.8% vs. 0.5%; P < 0.001) and their adjusted health care costs during follow-up were 2.82 times higher than comparators (P < 0.001; 95% confidence interval: 2.08-3.81). The incremental cost of pertussis during the 12-month follow-up period averaged $8271 (P < 0.001). The average incremental cost varied substantially by age, ranging from $18,781 (P < 0.001) to $3772 (P = 0.02) among infants 1 month and 7-12 months of age, respectively. CONCLUSIONS: The health burden of pertussis, particularly in the youngest infants, remains substantial, highlighting the need to intensify efforts to protect this most vulnerable population.

Inequalities in access to medical care by income in developed countries.

BACKGROUND: Most of the member countries of the Organization for Economic Cooperation and Development (OECD) aim to ensure equitable access to health care. This is often interpreted as requiring that care be available on the basis of need and not willingness or ability to pay. We sought to examine equity in physician utilization in 21 OECD countries for the year 2000. METHODS: Using data from national surveys or from the European Community Household Panel, we extracted the number of visits to a general practitioner or medical specialist over the previous 12 months. Visits were standardized for need differences using age, sex and reported health levels as proxies. We measured inequity in doctor utilization by income using concentration indices of the need-standardized use. RESULTS: We found inequity in physician utilization favouring patients who are better off in about half of the OECD countries studied. The degree of pro-rich inequity in doctor use is highest in the United States and Mexico, followed by Finland, Portugal and Sweden. In most countries, we found no evidence of inequity in the distribution of general practitioner visits across income groups, and where it does occur, it often indicates a pro-poor distribution. However, in all countries for which data are available, after controlling for need differences, people with higher incomes are significantly more likely to see a specialist than people with lower incomes and, in most countries, also more frequently. Pro-rich inequity is especially large in Portugal, Finland and Ireland. INTERPRETATION: Although in most OECD countries general practitioner care is distributed fairly equally and is often even pro-poor, the very pro-rich distribution of specialist care tends to make total doctor utilization somewhat pro-rich. This phenomenon appears to be universal, but it is reinforced when private insurance or private care options are offered.

Vaccine Timeliness: A Cost Analysis of the Potential Implications of Delayed Pertussis Vaccination in the US.

BACKGROUND: Pertussis infection remains an important public health problem, particularly in infants. Despite high coverage, pertussis vaccination delays can leave infants at a vulnerable age with less protection than anticipated. METHODS: Current diphtheria-tetanus-pertussis (DTaP) vaccination timeliness for the first 3 doses in the US was estimated using National Immunization Survey data. A Markov model estimated the potential impact on outcomes and costs of a hypothetical situation of vaccination at exactly 60, 120 and 180 days, compared with current timeliness. Incidence and unit cost data came from published sources. Age-specific incidence (for month of life) of pertussis and the associated probabilities of hospitalization and death for the US, during 2000-2007, were taken from a recently published US DTaP vaccination cost-effectiveness study. The cost analysis was conducted from the healthcare system's perspective over a 1-year time horizon. A regression analysis was conducted to explore the factors associated with vaccination delay. RESULTS: Current DTaP vaccination was estimated to be delayed by 16, 27 and 44 days, for the first, second and third doses, respectively, relative to vaccination at exactly 60, 120 and 180 days. The model estimated that vaccination at exactly age 60, 120 and 180 days could prevent approximately 278 pertussis cases, 103 hospitalizations and 1 death in infants aged <1 year in the US, gaining approximately 38 quality-adjusted life years and saving approximately $1.03 million in healthcare costs. CONCLUSIONS: Timely administration of infant pertussis vaccine doses could potentially reduce subsequent pertussis cases, hospitalizations, deaths and medical costs in infants aged <1 year in the US.

Mixing of diphtheria, tetanus, and acellular pertussis (DTaP) vaccines in a population of children in managed care.

The Advisory Committee on Immunization Practices recommends administering diphtheria, tetanus and acellular pertussis (DTaP) vaccines to children at 2, 4, 6, 15-18 months, and 4-6 y of age; preferably with the same-brand vaccine for the whole series. We estimated age-appropriate DTaP dose completion and the proportion of children receiving a "mixed" DTaP vaccination series (ie, including DTaP vaccines from ≥ 2 brands) across the 3 milestones. Commercially-insured children born between 01/01/2003 and 04/30/2011 were identified from United States health insurance claims data and assigned to ≥ 1 of 3 study cohorts based on the duration of continuous health plan enrollment: 1) birth to <8 months; 2) birth to <20 months; 3) birth to <7 years. Dose completion and brand mixing of the first 3, first 4 or all 5 doses were measured in the respective cohorts. Administered DTaP vaccinations were identified in claims data and classified by brand (based on vaccine components and manufacturer). The analysis included children who received ≥ 2 DTaP vaccinations and had known brand information for all doses. Age-appropriate dose completion was 77% with 3 doses (<8 months cohort), 71% with 4 doses (<20 months cohort), and 85% with 5 doses (<7 years cohort). Mixed DTaP series were received by 4.7% (95% confidence interval [CI]: 4.6%-4.7%) in the <8 months cohort, 29.0% (95% CI: 28.6%-29.4%) in the <20 months cohort, and 39.0% (95% CI: 34.5, 43.6) in the <7 years cohort. DTaP mixing was just 4.7% for the first 3 doses but subsequently increased with the number of administered doses.