Lessons learned from a multi-data source research collaboration: The mirabegron post-authorization safety study program.

BACKGROUND: Many factors contribute to developing and conducting a successful multi-data source, non-interventional, post-authorization safety study (NI-PASS) for submission to multiple health authorities. Such studies are often large undertakings; evaluating and sharing lessons learned can provide useful insights to others considering similar studies. OBJECTIVES: We discuss challenges and key methodological and organizational factors that led to the delivery of a successful post-marketing requirement (PMR)/PASS program investigating the risk of cardiovascular and cancer events among users of mirabegron, an oral medication for the treatment of overactive bladder. RESULTS: We provide context and share learnings, including sections on research program collaboration, scientific transparency, organizational approach, mitigation of uncertainty around potential delays, validity of study outcomes, selection of data sources and optimizing patient numbers, choice of comparator groups and enhancing precision of estimates of associations, potential confounding and generalizability of study findings, and interpretation of results. CONCLUSIONS: This large PMR/PASS program was a long-term commitment from all parties and benefited from an effective coordinating center and extensive scientific interactions across research partners, scientific advisory board, study sponsor, and health authorities, and delivered useful learnings related to the design and organization of multi-data source NI-PASS.

Incidence rates of thrombosis with thrombocytopenia syndrome (TTS) among adults in United States commercial and Medicare claims databases, 2017-2020.

BACKGROUND: Increased risk of thrombosis with thrombocytopenia syndrome (TTS) following adenovirus vector-based COVID-19 vaccinations has been identified in passive surveillance systems. TTS incidence rates (IRs) in the United States (U.S.) are needed to contextualize reports following COVID-19 vaccination. METHODS: We estimated annual and monthly IRs of overall TTS, common site TTS, and unusual site TTS for adults aged 18-64 years in Carelon Research and MarketScan commercial claims (2017-Oct 2020), CVS Health and Optum commercial claims (2019-Oct 2020), and adults aged ≥ 65 years using CMS Medicare claims (2019-Oct 2020); IRs were stratified by age, sex, and race/ethnicity (CMS Medicare). RESULTS: Across data sources, annual IRs for overall TTS were similar between Jan-Dec 2019 and Jan-Oct 2020. Rates were higher in Medicare (IRs: 370.72 and 365.63 per 100,000 person-years for 2019 and 2020, respectively) than commercial data sources (MarketScan IRs: 24.21 and 24.06 per 100,000 person-years; Optum IRs: 32.60 and 31.29 per 100,000 person-years; Carelon Research IRs: 24.46 and 26.16 per 100,000 person-years; CVS Health IRs: 30.31 and 30.25 per 100,000 person-years). Across years and databases, common site TTS IRs increased with age and were higher among males. Among adults aged ≥ 65 years, the common site TTS IR was highest among non-Hispanic black adults. Annual unusual site TTS IRs ranged between 2.02 and 3.04 (commercial) and 12.49 (Medicare) per 100,000 person-years for Jan-Dec 2019; IRs ranged between 1.53 and 2.67 (commercial) and 11.57 (Medicare) per 100,000 person-years for Jan-Oct 2020. Unusual site TTS IRs were higher in males and increased with age in commercial data sources; among adults aged ≥ 65 years, IRs decreased with age and were highest among non-Hispanic American Indian/Alaska native adults. CONCLUSION: TTS IRs were generally similar across years, higher for males, and increased with age. These rates may contribute to surveillance of post-vaccination TTS.

Cervical High-Grade Squamous Intraepithelial Lesion Burden and Standard of Care Treatment Effectiveness and Safety in the United States, 2008-2018: The EACH-WOMAN Project.

OBJECTIVE: Management of cervical high-grade squamous intraepithelial lesions (HSILs), the immediate precursor of cervical cancer, consists largely of surgical treatment for women at higher risk for progression to cancer. The authors' objective was to describe the occurrence of cervical HSIL in the United States and various outcomes for women who received surgical treatment. METHODS: From a US commercial health insurer, a cohort of adult women with cervical HSIL diagnoses receiving surgical treatment within 3 months of diagnosis between January 2008 and September 2018 was identified. This cohort was followed for several outcomes, including cervical HSIL recurrence, human papillomavirus clearance, preterm birth, infection, and bleeding. RESULTS: The incidence rate of cervical HSIL declined from 2.34 (95% CI = 2.30-2.39) cases per 1,000 person-years in 2008 to 1.39 (95% CI = 1.35-1.43) cases per 1,000 person-years in 2014, remaining near that level through 2018. Among 65,527 women with cervical HSIL, 47,067 (72%) received surgical treatment within 3 months of diagnosis. Among the women receiving surgical treatment, cervical HSIL recurred in 6% of surgically treated women, whereas 45% of surgically treated women underwent subsequent virological testing that indicated human papillomavirus clearance. Preterm birth was observed in 5.9% by 5 years follow-up and bleeding and infection each at 2.2% by 7 days follow-up. CONCLUSIONS: From 2008 through 2018, the incidence of diagnosed cervical HSIL decreased for several years before stabilizing. Surgical treatment of HSIL may be beneficial in removing the precancerous lesion, but cervical HSIL may recur, and the surgery is associated with complications including preterm birth, infection, and bleeding.

Incident autoimmune conditions among males receiving quadrivalent human papillomavirus vaccine in the United States.

BACKGROUND: The potential for vaccines to induce autoimmunity has been the subject of considerable investigation and autoimmune induction remains a common focus for vaccine safety research. This study assessed the risk of new onset autoimmune conditions among males receiving the 4-valent human papillomavirus (HPV) vaccine (4vHPV). METHODS: Within a US health insurance claims database, we formed a cohort of male 4vHPV vaccine recipients between 2009 and 2016, along with a propensity score matched cohort of males who did not receive the 4vHPV vaccine. The study outcome was new onset autoimmune conditions (20 separate conditions) within four categories (rheumatologic/hematologic, gastroenterologic, endocrinologic and neurologic/ophthalmalogic). Outcomes identified using diagnosis codes were adjudicated through medical record review. Incidence rates (per 1,000 person-years) were estimated for the vaccinated and unvaccinated groups along with rate ratios (RRs). RESULTS: There were 65,606 males receiving at least one dose of 4vHPV vaccine, and 55,670 were matched to a comparator. The matched 4vHPV vaccine cohort provided 35 confirmed cases among 39,735 person-years, for an incidence rate of 0.88 (95% CI: 0.61-1.23), while the comparator cohort provided 47 confirmed cases among 58,215 person-years, an incidence rate of 0.81 (0.59-1.07), a RR of 1.09 (0.70-1.69). The RR within categories was 0.49 (0.10-2.42) for rheumatologic/hematologic, 1.26 (0.58-2.71) for gastroenterologic, 1.11 (0.61-2.02) for endocrinologic and 1.46 (0.21-10.40) for neurologic. CONCLUSIONS: The incidence of autoimmune conditions among males receiving the 4vHPV vaccine was similar to that among unvaccinated males. These results are consistent with other studies that have assessed autoimmunity with the 4vHPV vaccine.

Safety of 4-valent human papillomavirus vaccine in males: a large observational post-marketing study.

The 4-valent human papillomavirus (HPV) vaccine (4vHPV vaccine), Gardasil®, is indicated for the prevention of several HPV-related diseases. The objective was to assess the safety of 4vHPV vaccine administered to males as part of routine care. The study used a US health insurance claims database, and included males, age 9 to 26 years, who initiated 4vHPV between October 2009 and December 2016. General safety outcomes were identified using ICD diagnosis codes associated with emergency room visits and hospitalizations in the claims database in risk periods (Days 1-60 and Days 1-14 following vaccine administration) and self-comparison periods (Days 91-150 and 91-104 for the Days 1-60 and Days 1-14 analysis, respectively). Incidence rates (IRs) and relative rates (RRs) with 95% confidence intervals (CIs) were calculated comparing the risk and self-comparison periods. In this study, 114,035 males initiated 4vHPV vaccine and received 202,737 doses. Using the 60-day time window, 5 outcomes had significantly elevated RRs after accounting for multiple comparisons: ear conditions (RR 1.28, 95% CI 1.03-1.59); otitis media and related conditions (RR 1.65, 95% CI 1.09-2.54); cellulitis and abscess of arm (RR 2.17, 95% CI 1.06-4.72); intracranial injury (RR 1.23, 95% CI 1.01-1.50); and concussion (RR 1.29, 95% CI 1.05-1.59). A higher rate of allergic reactions was noted on the day of 4vHPV vaccine receipt compared to other vaccines (21.07 events per 10,000 doses, 95% CI 18.89-23.44 versus 11.44 per 10,000 doses, 95% CI 9.84-13.22). A higher incidence rate of VTE was observed following vaccination but this association was not significant (RR 2.17, 95% CI 0.35-22.74). The 4vHPV vaccine was associated with same-day allergic reactions as well as ear infections, intracranial injury, cellulitis, and concussion within 2 months after vaccination. While allergic reaction and cellulitis are consistent with the known safety profile of 4vHPV vaccine, the association of the other outcomes were determined by an independent Safety Review Committee to be most likely a result of activities common in adolescent males that coincide with the timing of vaccination and not directly related to vaccination itself.Implications and Contributions: The study results support the general safety of routine immunization with 4vHPV vaccine among males to prevent HPV-related diseases and cancers.

Identification of pregnancies and infants within a US commercial healthcare administrative claims database.

PURPOSE: Health care insurance claims databases are becoming a more common data source for studies of medication safety during pregnancy. While pregnancies have historically been identified in such databases by pregnancy outcomes, International Classification of Diseases, 10th revision Clinical Modification (ICD-10-CM) Z3A codes denoting weeks of gestation provide more granular information on pregnancies and pregnancy periods (i.e., start and end dates). The purpose of this study was to develop a process that uses Z3A codes to identify pregnancies, pregnancy periods, and links infants within a commercial health insurance claims database. METHODS: We identified pregnancies, gestation periods, pregnancy outcomes, and linked infants within the US-based Optum Research Database between 2015 and 2020 via a series of algorithms utilizing diagnosis and procedure codes on claims. The diagnosis and procedure codes included ICD-10-CM codes, Current Procedural Terminology (CPT) codes, and Healthcare Common Procedure Coding System (HCPCS) codes. RESULTS: We identified 1 030 874 pregnancies among 841 196 women of reproductive age. Of pregnancies with livebirth outcomes, 84% were successfully linked to infants. The prevalence of pregnancy outcomes (livebirth, stillbirth, ectopic, molar, and abortion) was similar to national estimates. CONCLUSIONS: This process provides an opportunity to study drug safety and care patterns during pregnancy and may be replicated in other claims databases containing ICD-10-CM, CPT, and HCPCS codes. Work is underway to validate and refine the various algorithms.

Vaccine initiation and 3-dose series completion of 4vHPV vaccine among US insured males 2012-2016.

OBJECTIVE: The quadrivalent human papillomavirus vaccine (4vHPV, GARDASIL®), was approved in the US in 2009 for use in males aged 9 to 26 for the prevention of HPV-related genital warts, and in 2010 for the prevention of certain HPV-related anogenital diseases. A regimen was approved in 2016 for those who initiate the vaccine series between the ages of 9 to 14 years. We describe patterns of 4vHPV administration among US males before this modification. METHODS: The study used a US health insurance claims database, and included males, age 9 to 26 years, who initiated 4vHPV between 2012 and 2016. Time from first dose to subsequent doses was estimated. Logistic regression identified factors associated with regimen completion. RESULTS: Among 100,786 males who initiated 4vHPV (corresponding to âˆ¼ 13% of male birth cohorts), 50,573 (50.2%) and 25,763 (25.6%) received a second and third dose, respectively. Annual administration was common, with 47% of males receiving 3 doses over 3 years (1 dose per year) as compared to 12% receiving the 3-dose series in the recommended 6-month timeframe. Receipt of 4vHPV was 2.2 (range 1.5 to 2.9) times as likely to occur in summer months compared to other times of the year. Individuals aged 18 to 21 years and those living in Western states or rural regions were less likely to complete the 3-dose regimen. CONCLUSIONS: The real-world patterns of 4vHPV vaccination observed, particularly the low uptake and regimen completion, suggest that better strategies are needed for males to improve 4vHPV vaccine use in males.

Post-approval Safety Surveillance Study of Golimumab in the Treatment of Rheumatic Disease Using a United States Healthcare Claims Database.

BACKGROUND AND OBJECTIVE: Golimumab is a fully human anti-tumor necrosis factor monoclonal antibody approved for the treatment of rheumatoid arthritis (RA), psoriatic arthritis (PsA), and ankylosing spondylitis (AS). This study estimated rates of prespecified outcomes in patients with RA, PsA or AS initiating golimumab versus matched patients initiating non-biologic systemic (NBS) medications. METHODS: Patients enrolled in a US health plan with rheumatic disease who initiated a study medication were accrued between April 2009 and November 2014. Golimumab initiators were matched by propensity score to NBS initiators in a 1:4 ratio. Outcomes were identified through September 2015. As-treated, as-matched, and nested case-control (NCC) analyses were conducted in the matched cohorts. Sensitivity analyses evaluated the impact of residual confounding and nondifferential misclassification of exposure and outcomes. RESULTS: Risks of outcomes were similar between golimumab and NBS initiators. In the as-treated analysis, the rate ratio (RR) for depression was elevated during current golimumab use versus golimumab non-use in the NBS cohort [RR 1.45, 95% confidence interval (CI) 1.31-1.61]. This finding was not replicated in as-matched (RR 1.08, 95% CI 0.97-1.19) or NCC (odds ratio 1.01, 95% CI 0.78-1.31) analyses, which focused on incident cases. Sensitivity analyses suggest that depression was sensitive to misclassification, and the RR changed from greater than to less than one across a plausible range of specificity. CONCLUSIONS: This study suggests that there is no association between exposure to golimumab and an increased risk of prespecified outcomes. Increased depression risk in the as-treated analysis was not replicated in other analyses and may be associated with residual imbalance in baseline history or severity of depression.

Glucose-lowering medications and the risk of cancer: A methodological review of studies based on real-world data.

AIM: To review the methodology of observational studies examining the association between glucose-lowering medications and cancer to identify the most common methodological challenges and sources of bias. METHODS: We searched PubMed systematically to identify observational studies on glucose-lowering medications and cancer published between January 2000 and January 2016. We assessed the design and analytical methods used in each study, with a focus on their ability to achieve study validity, and further evaluated the prevalence of major methodological choices over time. RESULTS: Of 155 studies evaluated, only 26% implemented a new-user design, 41% used an active comparator, 33% implemented a lag or latency period, and 51% adjusted for diabetes duration. Potential for immortal person-time bias was identified in 63% of the studies; 55% of the studies adjusted for variables measured during the follow-up without appropriate statistical methods. Aside from a decreasing trend in adjusting for variables measured during the follow-up, we observed no trends in methodological choices over time. CONCLUSIONS: The prevalence of well-known design and analysis flaws that may lead to biased results remains high among observational studies on glucose-lowering medications and cancer, limiting the conclusions that can be drawn from these studies. Avoiding known pitfalls could substantially improve the quality and validity of real-world evidence in this field.

Liraglutide use and evaluation of pancreatic outcomes in a US commercially insured population.

AIMS: Both acute pancreatitis (AP) and pancreatic cancer (PC) have been areas of focus for studies of incretin drugs. This 5-year prospective cohort study aimed to quantify possible associations between liraglutide and risk of AP and PC as compared to other antidiabetic drugs (ADs). MATERIALS AND METHODS: Patients initiating liraglutide or other ADs who were enrolled in a US health plan (2010-2014) were included. Comparisons of AP and PC incidence rates were made between matched cohorts of liraglutide initiators and initiators of other ADs. Adjudicated AP cases and algorithm-based PC cases were identified. Propensity score-matched intention-to-treat (ITT) and time-on-drug (TOD) analyses were completed using Poisson regression. A latency analysis was performed for PC. RESULTS: Median follow-up was 405 days for AP cohorts (9995 liraglutide, 1:1 matched to all comparators) and 503 days for PC cohorts (35 163 liraglutide, 1:1 matched to all comparators). In the primary AP analysis, "current" use of liraglutide was not significantly associated with elevated risk across comparators (all comparators relative risk [RR] = 1.2; 95% confidence interval [CI], 0.6-2.3). ITT results were similar where, in the primary analysis, no RRs were significantly associated with PC (all comparators RR = 0.7; 95% CI, 0.3-1.4); latency and TOD analyses did not alter findings. There was no evidence of a dose-response effect. CONCLUSIONS: Liraglutide was not associated with an increased risk of AP or PC, although risk estimates were more variable for AP, and numbers of cases for both outcomes were limited because of the rarity of outcomes.

Assessment of Risk Evaluation and Mitigation Strategies (REMS) for varenicline (Chantix): A multistage patient survey.

PURPOSE: To evaluate the Risk Evaluation and Mitigation Strategies (REMS) for varenicline by assessing patients' understanding of the varenicline medication guide (MG) at pre-specified time points: 18 months, 3 years, and 7 years after the REMS approval. METHODS: Self-administered surveys were mailed to people who received varenicline based on a pharmacy dispensing. Survey questions assessed understanding of potential risks outlined in the MG: neuropsychiatric symptoms, skin reactions, allergic reactions, and cardiovascular risks. Crude and weighted analyses were conducted. RESULTS: The response to the survey overall was between 18% and 19%. Among responders, approximately 90% recalled receiving the MG, and at least 80% read all or part of it. At least 88% correctly identified neuropsychiatric symptoms as potential medication effects, while 41% did so for skin reactions, 53% for allergic reactions, and 82% for cardiovascular risks. Patients who read the MG had a high proportion of correct responses to the risk comprehension questions. CONCLUSIONS: A large majority of patients who were dispensed varenicline recalled receiving the MG and were able to correctly recall neuropsychiatric and cardiovascular risks in all 3 surveys. The varenicline MG may be an effective tool for patient education.

Comparative Effectiveness of Carotid Artery Stenting Versus Carotid Endarterectomy Among Medicare Beneficiaries.

BACKGROUND: Effectiveness of carotid artery stenting (CAS) relative to carotid endarterectomy (CEA) among Medicare patients has not been established. We compared effectiveness of CAS versus CEA among Medicare beneficiaries. METHODS AND RESULTS: We linked Medicare data (2000-2009) to the Society for Vascular Surgery's Vascular Registry (2005-2008) and the National Cardiovascular Data Registry's (NCDR) Carotid Artery Revascularization and Endarterectomy Registry (2006-2008/2009). Medicare patients were followed up from procedure date until death, stroke/transient ischemic attack, periprocedural myocardial infarction, or a composite end point for these outcomes. We derived high-dimensional propensity scores using registry and Medicare data to control for patient factors and adjusted for provider factors in a Cox regression model comparing CAS with CEA. Among 5254 Society for Vascular Surgery's Vascular Registry (1999 CAS; 3255 CEA) and 4055 Carotid Artery Revascularization and Endarterectomy Registry (2824 CAS; 1231 CEA) Medicare patients, CAS patients had a higher comorbidity burden and were more likely to be at high surgical risk (Society for Vascular Surgery's Vascular Registry: 96.7% versus 44.5%; Carotid Artery Revascularization and Endarterectomy Registry: 71.3% versus 44.7%). Unadjusted outcome risks were higher for CAS. Mortality risks remained elevated for CAS after adjusting for patient-level factors (hazard ratio, 1.24; 95% confidence interval, 1.06-1.46). After further adjustment for provider factors, differences between CAS and CEA were attenuated or no longer present (hazard ratio for mortality, 1.13; 95% confidence interval, 0.94-1.37). Performance was comparable across subgroups defined by sex and degree of carotid stenosis, but there was a nonsignificant trend suggesting a higher risk of adverse outcomes in older (>80) and symptomatic patients undergoing CAS. CONCLUSIONS: Outcomes after CAS and CEA among Medicare beneficiaries were comparable after adjusting for both patient- and provider-level factors.

Implications of immortal person-time when outcomes are nonfatal.

PURPOSE: The amount of immortal time bias in studies with nonfatal outcomes is unclear. To quantify the magnitude of bias from mishandling of immortal person-time in studies of nonfatal outcomes. METHODS: We derived formulas for quantifying bias from misclassified or excluded immortal person-time in settings with nonfatal outcomes, assuming a constant rate of outcome. In the situation of misclassified or excluded immortal person-time, the quantification includes the immortal time and corresponding events mistakenly attributed to the exposed group (misclassified) or excluded from study (excluded) that must be attributed to the comparison group. RESULTS: With misclassified immortal person-time, the magnitude of bias varies according to the incidence rate ratio of immortal time and comparison group as well as the rate ratio of immortal time and exposed group: toward null for both ratios less than 1, no bias for both ratios equal to 1, away from null for both ratios greater than 1. For one ratio less than 1 and the other greater than 1, the direction and magnitude of bias can be obtained from the formula provided. With excluded immortal person-time, the magnitude of bias is associated with the incidence rate ratio of immortal time and comparison group: toward null for the ratio less than 1, no bias for the ratio equal to 1, and away from null for the ratio greater than 1. CONCLUSIONS: Bias due to immortal person-time in studies with nonfatal outcomes can vary widely and can be quantified under assumptions that apply to many studies.

Safety and effectiveness of dabigatran and warfarin in routine care of patients with atrial fibrillation.

The RE-LY study demonstrated the safety and efficacy of dabigatran relative to warfarin for stroke prevention in non-valvular atrial fibrillation. It is important to further evaluate safety and effectiveness of drugs in routine care. This study used a sequential cohort design with propensity score matching to compare dabigatran with warfarin among patients in two commercial health insurance databases. New users of these anticoagulants were followed from initiation until discontinuation, the end of the study, or the occurrence of a study outcome (primary study outcomes were stroke and major bleeding). Proportional hazards regression was conducted separately within each data source and results were pooled. Among 19,189 matched dabigatran and warfarin initiators (mean age: 68 years, 36 % female), as-treated follow-up (average of 5 months for dabigatran, 4 months for warfarin) identified 62 and 69 strokes, respectively (pooled HR = 0.77; 95 % CI = 0.54 to 1.09), and 354 and 395 major haemorrhages, respectively (HR = 0.75; 0.65 to 0.87). No meaningful heterogeneity was identified across subgroups, but numeric trends suggest more pronounced stroke prevention by dabigatran relative to warfarin among patients age 75+ (HR = 0.57; 0.33 to 0.97) or with < 6 months of use (HR = 0.51; 0.19 to 1.42). Major bleeds were reduced more by dabigatran among patients aged < 55 (HR = 0.51; 0.30 to 0.87) and with CHADS2 < 2 (HR = 0.58; 0.44 to 0.77). In conclusion, in routine care of patients with non-valvular atrial fibrillation, dabigatran treatment resulted in improved health outcomes compared with warfarin.

Selective Serotonin Reuptake Inhibitor Use and Perioperative Bleeding and Mortality in Patients Undergoing Coronary Artery Bypass Grafting: A Cohort Study.

INTRODUCTION: Several small studies have reported inconsistent findings about the safety of selective serotonin reuptake inhibitors (SSRIs) among patients undergoing coronary artery bypass grafting (CABG). We sought to investigate post-CABG bleeding and mortality outcomes related to antidepressant exposure. METHODS: We identified patients who underwent CABG between 2004 and 2008 in the Premier Perspective Comparative Database. We determined whether they received SSRIs, other antidepressants, or no antidepressants on any pre-CABG hospital day and used Cox proportional hazards models to compare bleeding and mortality rates among the exposure groups while adjusting for potential confounders based on administrative data, pre-CABG charge codes, and discharge diagnosis codes. RESULTS: We identified 132,686 eligible patients: 7112 exposed to SSRIs, 1905 exposed to other antidepressants, and 123,668 unexposed. As compared with no exposure, neither SSRIs (hazard ratio [HR] 0.98; 95 % confidence interval [CI] 0.90-1.07) nor other antidepressants (HR 1.11; 95 % CI 0.96-1.28) increased major bleeds, and neither SSRIs (HR 0.93; 95 % CI 0.80-1.07) nor other antidepressants (HR 0.84; 95 % CI 0.62-1.14) increased mortality. Both SSRIs (HR 1.14; 95 % CI 1.10-1.18) and other antidepressants (HR 1.11; 95 % CI 1.03-1.19) were associated with a slight increase in receipt of one or more packed red blood cell (pRBC) units, but neither were associated with substantial increases in receipt of three or more pRBC units (HR 1.06; 95 % CI 0.96-1.17 for SSRIs; HR 1.09; 95 % CI 0.91-1.31 for other antidepressants). CONCLUSION: In this large cohort study, neither SSRIs nor other antidepressants were associated with elevated rates of major bleed, or in-hospital mortality.

Human papillomavirus vaccine uptake among individuals with systemic inflammatory diseases.

OBJECTIVES: The human papillomavirus (HPV) vaccine is safe and efficacious in patients with systemic inflammatory diseases (SID) who have higher rates of persistent HPV infection. We compared HPV vaccine uptake among SID and non-SID patients. METHODS: Using a U.S. insurance claims database (2006-2012), we identified individuals 9-26 years with ≥2 SID diagnosis codes ≥7 days apart with ≥12 months of continuous enrollment prior to the second code (index date). We matched SID patients by age, sex and index date to randomly selected non-SID subjects and selected those with ≥24 months of post-index date continuous follow-up. We also identified a non-SID subcohort with ≥1 diagnosis code for asthma. We defined initiation as ≥1 HPV vaccination claim after 2007, and completion as 3 claims. We used multivariable logistic regression to assess uptake in females 11-26 years comparing SID, non-SID and asthma cohorts, adjusting for demographics, region, comorbidities, and healthcare utilization. RESULTS: We identified 5,642 patients 9-26 years with SID and 20,643 without. The mean age was 18.1 years (SD 4.9). We identified 1,083 patients with asthma; the mean age was 17.2 (SD 5.1). Among females, 20.6% with SID, 23.1% without SID and 22.9% with asthma, received ≥1 HPV vaccine. In our adjusted models, the odds of receipt of ≥1 vaccine was 0.87 times lower in SID (95% CI 0.77-0.98) compared to non-SID and did not differ for 3 vaccines (OR 1.03, 95% CI 0.83-1.26). The odds of initiation and completion were not statistically different between SID and non-SID asthma cohorts. CONCLUSIONS: In this nationwide cohort, HPV vaccine uptake was extremely low. Despite the heightened risk of persistent HPV infection among those with SID, no increase in HPV vaccine uptake was observed. Public health efforts to promote HPV vaccination overall are needed, and may be particularly beneficial for those at higher risk.

Allopurinol initiation and all-cause mortality in the general population.

BACKGROUND: Allopurinol is the most commonly used urate-lowering therapy, with rare but potentially fatal adverse effects. However, its impact on overall mortality remains largely unknown. In this study, we evaluated the impact of allopurinol initiation on the risk of mortality among individuals with hyperuricaemia and among those with gout in the general population. METHODS: We conducted an incident user cohort study with propensity score matching using a UK general population database. The study population included individuals aged ≥40 years who had a record of hyperuricaemia (serum urate level >357 µmol/L for women and >416 µmol/L for men) between January 2000 and May 2010. To closely account for potential confounders of allopurinol use and risk of death, we constructed propensity score matched cohorts of allopurinol initiators and comparators (non-initiators) within 6-month cohort accrual blocks. RESULTS: Of 5927 allopurinol initiators and 5927 matched comparators, 654 and 718, respectively, died during the follow-up (mean=2.9 years). The baseline characteristics were well balanced in the two groups, including the prevalence of gout in each group (84%). Allopurinol initiation was associated with a lower risk of all-cause mortality (matched HR 0.89 (95% CI 0.80 to 0.99)). When we limited the analysis to those with gout, the corresponding HR was 0.81 (95% CI 0.70 to 0.92). CONCLUSIONS: In this general population study, allopurinol initiation was associated with a modestly reduced risk of death in patients with hyperuricaemia and patients with gout. The overall benefit of allopurinol on survival may outweigh the impact of rare serious adverse effects.

A pooled analysis of exenatide use and risk of acute pancreatitis.

OBJECTIVE: To estimate the association between exenatide BID use and acute pancreatitis across two claims-based studies. RESEARCH DESIGN AND METHODS: We pooled two cohort studies within separate commercial health insurance databases. We included initiators of exenatide BID and all other antihyperglycemic drugs without prior pancreatitis from 2005-2008. Poisson regression models provided rate ratios (RRs) and 95% confidence intervals (CIs) of the association of exenatide BID with acute pancreatitis adjusted for quintiles of propensity scores. MAIN OUTCOME MEASURES: Primary inpatient diagnoses of acute pancreatitis with correction for misclassification via a validation sub-study. RESULTS: There were 49,956 initiators of exenatide BID and 692,333 initiators of other antihyperglycemic drugs. Patients in the two studies were similar on many demographic and clinical characteristics. Exenatide BID initiators had a higher prevalence of diagnoses consistent with diabetes complications (e.g. peripheral neuropathy) and cardiovascular risk factors (e.g. hypertension). In both studies, current exenatide BID use was not associated with uncorrected outcomes of acute pancreatitis (pooled RR 1.0; CI 0.8-1.3). PPV correction resulted in a slightly higher point estimate for current use (pooled RR 1.3; CI 1.0-1.7) and past use (pooled RR 1.6; 95% CI 1.2-2.1). CONCLUSIONS: These data are consistent with little or no higher risk of acute pancreatitis associated with current exenatide BID use relative to nonuse. Although previous work identified non-causal mechanisms, an increased incidence of acute pancreatitis following cessation of treatment remains a possibility. Bias due to residual confounding or outcome misclassification may remain, and should be considered a potential explanation for these findings.

The effectiveness of varenicline medication guide for conveying safety information to patients: a REMS assessment survey.

PURPOSE: Risk Evaluation and Mitigation Strategies (REMS) include various mechanisms to enhance safe use of medications, including a patient medication guide (MG) that provides key information regarding the potential risks associated with the medication. To evaluate the effectiveness of the varenicline MG as a REMS tool for educating patients, we undertook a survey among patients who were dispensed varenicline. METHODS: Varenicline recipients within the Optum Research Database, a large U.S. administrative claims database, were invited to participate in a self-administered survey. Survey questions were general (receipt and reading of the MG) and specific regarding patient's understanding of the potential varenicline risks outlined in the MG (neuropsychiatric symptoms, skin reactions, and allergic reactions). RESULTS: From 3568 varenicline recipients invited, 640 (18%) responded, with 633 completing at least one of three risk-comprehension questions. The majority (93%) indicated receiving the MG, and 86% read all or part of it. Ninety-one percent, 41%, and 53% correctly answered at least one question on neuropsychiatric symptoms, skin reactions, and allergic reactions, respectively. A higher proportion who read the MG had correct responses to the risk-comprehension questions than those who did not read it. CONCLUSIONS: The varenicline MG was widely received and read among survey respondents, and the information conveyed was generally well understood regarding potential risk of neuropsychiatric symptoms. This study provides an assessment of the effectiveness of the varenicline MG in communicating information about potential risks associated with varenicline. This assessment method may apply to the evaluation of the effectiveness of other MGs.

The Zelnorm epidemiologic study (ZEST): a cohort study evaluating incidence of abdominal and pelvic surgery related to tegaserod treatment.

BACKGROUND: Pre-marketing clinical studies of tegaserod suggested an increased risk of abdominal surgery, particularly cholecystectomy. We sought to quantify the association between tegaserod use and the occurrence of abdominal or pelvic surgery, including cholecystectomy. METHODS: This cohort study was conducted within an insured population. Tegaserod initiators and similar persons who did not initiate tegaserod were followed for up to six months for the occurrence of abdominal or pelvic surgery. Surgical procedures were identified from health insurance claims validated by review of medical records. The incidence of confirmed outcomes was compared using both as-matched and as-treated analyses. RESULTS: Among 2,762 tegaserod initiators, there were 94 abdominal or pelvic surgeries (36 gallbladder): among 2,762 comparators there were 134 abdominal or pelvic surgeries (37 gallbladder) (hazard ratio HR] = 0.70, 95% confidence interval [C.I.] = 0.54-0.91 overall, HR = 0.98, 95% C.I. = 0.62-1.55 for gallbladder). Current tegaserod exposure compared to nonexposure was associated with a rate ratio [RR] of 0.68 (95% C.I. = 0.48-0.95) overall, while the RR was 0.99 (95% C.I. = 0.56-1.77) for gallbladder surgery. CONCLUSIONS: In this study, tegaserod use was not found to increase the risk of abdominal or pelvic surgery nor the specific subset of gallbladder surgery.