Medicare claims versus beneficiary self-report for influenza vaccination surveillance.

BACKGROUND: Although self-reported influenza vaccination status is routinely used in surveillance to estimate influenza vaccine coverage, Medicare data are becoming a promising resource for influenza surveillance to inform vaccination program management and planning. PURPOSE: To evaluate the concordance between self-reported influenza vaccination and influenza vaccination claims among Medicare beneficiaries. METHODS: This study compared influenza vaccination based upon Medicare claims and self-report among a sample of Medicare beneficiaries (N=9,378) from the 2011 Medicare Current Beneficiary Survey, which was the most recent year of data at the time of analysis (summer 2013). Sensitivity, specificity, positive predictive value, and negative predictive value were calculated using self-reported data as the referent standard. Logistic regression was used to compute the marginal mean proportions for whether a Medicare influenza vaccination claim was present among beneficiaries who reported receiving the vaccination. RESULTS: Influenza vaccination was higher for self-report (69.4%) than Medicare claims (48.3%). For Medicare claims, sensitivity=67.5%, specificity=96.3%, positive predictive value=97.6%, and negative predictive value=56.7%. Among beneficiaries reporting receiving an influenza vaccination, the percentage of beneficiaries with a vaccination claim was lower for beneficiaries who were aged <65 years, male, non-Hispanic black or Hispanic, and had less than a college education. CONCLUSIONS: The classification of influenza vaccination status for Medicare beneficiaries can differ based upon survey and claims. To improve Medicare claims-based surveillance studies, further research is needed to determine the sources of discordance in self-reported and Medicare claims data, specifically for sensitivity and negative predictive value.

Early mortality after aortic valve replacement with mechanical prosthetic vs bioprosthetic valves among Medicare beneficiaries: a population-based cohort study.

IMPORTANCE: Early mortality for patients who undergo aortic valve replacement (AVR) may differ between mechanical and biological prosthetic (hereinafter referred to as bioprosthetic) valves. Clinical trials may have difficulty addressing this issue owing to limited sample sizes and low mortality rates. OBJECTIVE: To compare early mortality after AVR between the recipients of mechanical and bioprosthetic aortic valves. DESIGN, SETTING, AND PARTICIPANTS: A retrospective analysis of patients 65 years or older in the Medicare databases who underwent AVR from July 1, 2006, through December 31, 2011. In the mixed-effects models adjusting for physician and hospital random effects, we estimated odds ratios (OR) of early mortality to compare mechanical vs bioprosthetic valves. EXPOSURES: Mechanical or bioprostheticaortic valve replacement. MAIN OUTCOMES AND MEASURES: Early mortality was measured as death on the date of surgery, death within 1 to 30 or 31 to 365 days after the date of surgery, death within 30 days after the date of hospital discharge, and operative mortality (death within 30 days after surgery or at discharge, whichever is longer). RESULTS: Of the 66 453 Medicare beneficiaries who met inclusion criteria, 19 190 (28.88%) received a mechanical valve and 47 263 (71.12%) received a bioprosthetic valve. The risk for death on the date of surgery was 60% higher for recipients of mechanical valves than recipients of bioprosthetic valves (OR, 1.61 [95% CI, 1.27-2.04; P < .001]; risk ratio [RR], 1.60). The risk difference decreased to 16% during the 30 days after the date of surgery (OR, 1.18 [95% CI, 1.09-1.28; P < .001]; RR, 1.16). We found no differences within 31 to 365 days after the date of surgery and within the 30 days after discharge. The risk for operative mortality was 19% higher for recipients of mechanical compared with bioprosthetic valves (OR, 1.21 [95% CI, 1.13-1.30; P < .001]; RR, 1.19). The number needed to treat with mechanical valves to observe 1 additional death on the surgery date was 290; to observe 1 additional death within 30 days of surgery, 121. Consistent findings were observed in subgroup analyses of patients who underwent concurrent AVR and coronary artery bypass graft, but not in the subgroup undergoing isolated AVR. CONCLUSIONS AND RELEVANCE: In this cohort analysis of Medicare beneficiaries, use of mechanical aortic valves was associated with a higher risk for death on the date of surgery and within the 30 days after surgery compared with bioprosthetic aortic valves among patients who underwent concurrent AVR and coronary artery bypass graft but not isolated AVR.

Use of an active surveillance system by the FDA to observe patterns of quinine sulfate use and adverse hematologic outcomes in CMS Medicare data.

PURPOSE: In 2005, the Food and Drug Administration approved Qualaquin (quinine) for treatment of malaria and later ordered unapproved quinine formulations off the market. In 2009, labeling for Qualaquin added a warning for use for leg cramps, as serious hematologic reactions could occur. We examined quinine use trends among Medicare beneficiaries focusing on indications for use and associations with adverse hematologic outcomes. METHODS: Medicare beneficiaries, aged 65 years and older, in 2006-2012, were included in incident quinine or comparator, diltiazem, cohorts if 183 days prior to dispensing, they were enrolled in Medicare, had no dispensing of quinine, diltiazem, ticlodipine, clopidogrel, and sulfonamide drugs, and had no diagnoses of thrombocytopenia, immune thrombocytopenic purpura (ITP), thrombotic microangiopathy (TMA), or hemolytic-uremic syndrome (HUS). Diagnoses of malaria or leg cramps were observed during 183 days prior to index dispensing. Outcomes of ITP, TMA, or HUS in inpatient or emergency room settings were then observed during drug use. RESULTS: Prevalent use of quinine decreased by 99%, from 419 675 to 6036 users during 2006-2012. Of 88 066 quinine users, 9 had diagnoses of malaria and 36 218 had leg cramps. Incidence rates (per 1000 person-years) for ITP were quinine 1.67 and diltiazem 0.40 [incidence rate ratio 4.2 (95% confidence interval 2.5, 6.5)], for TMA were quinine 0.23 and diltiazem 0.03 [incidence rate ratio 6.9 (95% confidence interval 1.3, 24.0)], and for HUS were quinine 0 and diltiazem 0.01. CONCLUSIONS: Use of quinine decreased substantially, although diagnoses of leg cramps persist. To our knowledge, this is the first demonstration of an association for quinine and ITP and TMA in claims data.

Incidence of endophthalmitis after corneal transplant or cataract surgery in a medicare population.

OBJECTIVE: To estimate the incidence of infectious endophthalmitis after corneal transplant or cataract surgery, to evaluate the trend of endophthalmitis during the study period, and to assess demographic risk factors for endophthalmitis after surgeries. DESIGN: A retrospective population-based cohort study. PARTICIPANTS AND CONTROLS: Study cohorts were derived from the Medicare claims databases, 2006 to 2011. Patients were continuously enrolled in Medicare Part A, Part B, and Part D. Patients undergoing corneal transplant or cataract surgery were identified using International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) procedure codes. METHODS: Endophthalmitis was defined in 3 different ways: (1) using ICD-9-CM codes (sensitive definition), (2) combining ICD-9-CM codes with Current Procedural Terminology, Fourth Edition (CPT-4) codes (specific definition), or (3) combining ICD-9-CM codes with antifungal prescriptions for endophthalmitis caused by fungal infection. Demographic risk factors for endophthalmitis were examined using multivariate Cox models. MAIN OUTCOME MEASURES: Incidence rates of endophthalmitis were calculated and compared for each definition of endophthalmitis at 6-week and 6-month intervals after corneal transplant or cataract surgery. RESULTS: The infectious endophthalmitis incidence rates ranged from 0.11% to 1.05% in the corneal transplant cohort, 0.06% to 0.20% in the cataract surgery cohort, and 0.16% to 0.68% in the concurrent surgery cohort, depending on the definition and time interval after surgery. Compared with the cataract surgery cohort, the corneal transplant cohort had a higher adjusted hazard ratio (HR) of endophthalmitis within the 6-week postoperative interval (HR, 2.744; 95% confidence interval [CI], 1.544-4.880 in the sensitive definition and HR, 2.792; 95% CI, 1.146-6.802 in the specific definition) and within the 6-month postoperative interval (HR, 4.607; 95% CI, 3.144-6.752 for the sensitive definition and HR, 4.385; 95% CI, 2.245-8.566 for the specific definition). CONCLUSIONS: It is possible to monitor the trend of infectious endophthalmitis after corneal transplant or cataract surgery through examining Medicare claims databases as long as a consistent definition of endophthalmitis is used. The annual incidence of endophthalmitis was stable over time during the study period for both corneal transplant and cataract surgery procedures; however, there was a wider year-to-year variation for the corneal transplant cohort.

Off-label topical calcineurin inhibitor use in children.

OBJECTIVE: To assess off-label use of the topical calcineurin inhibitors (TCIs), tacrolimus and pimecrolimus, in children during periods before and after regulatory action by the US Food and Drug Administration (FDA) in 2005. METHODS: We identified new pediatric (age <20 years) users of topical tacrolimus or pimecrolimus in US Medicaid from 2001 to 2009, and examined the annual rate of drug use (pre- and postregulatory action) by age. We assessed medical claims for diagnoses consistent with an indication for a TCI, and assessed prescriptions for evidence of first-line atopic dermatitis therapy use before TCI initiation. RESULTS: There were 57,664 eligible pediatric tacrolimus users and 425,242 eligible pediatric pimecrolimus users at baseline. The rate of TCI use decreased substantially after FDA regulatory action. The proportion of new users younger than 2 years of age significantly decreased for both tacrolimus (36.7% to 22.5%, P < .001) and pimecrolimus (47.0% to 33.7%, P < .001) after regulatory actions. Previous use of topical corticosteroids increased by ≈ 7% for both TCIs from the pre- to postregulatory period. However, after regulatory actions, there was only a small increase in the proportion of tacrolimus or pimecrolimus users with an atopic dermatitis or eczema diagnosis before drug initiation, and high strength use of tacrolimus was unchanged. CONCLUSIONS: The rate of TCI use in children younger than 2 years of age fell substantially after FDA regulatory action in 2005. Off-label use of TCI as first-line therapy changed little.