Drug safety data mining with a tree-based scan statistic.

PURPOSE: In post-marketing drug safety surveillance, data mining can potentially detect rare but serious adverse events. Assessing an entire collection of drug-event pairs is traditionally performed on a predefined level of granularity. It is unknown a priori whether a drug causes a very specific or a set of related adverse events, such as mitral valve disorders, all valve disorders, or different types of heart disease. This methodological paper evaluates the tree-based scan statistic data mining method to enhance drug safety surveillance. METHODS: We use a three-million-member electronic health records database from the HMO Research Network. Using the tree-based scan statistic, we assess the safety of selected antifungal and diabetes drugs, simultaneously evaluating overlapping diagnosis groups at different granularity levels, adjusting for multiple testing. Expected and observed adverse event counts were adjusted for age, sex, and health plan, producing a log likelihood ratio test statistic. RESULTS: Out of 732 evaluated disease groupings, 24 were statistically significant, divided among 10 non-overlapping disease categories. Five of the 10 signals are known adverse effects, four are likely due to confounding by indication, while one may warrant further investigation. CONCLUSION: The tree-based scan statistic can be successfully applied as a data mining tool in drug safety surveillance using observational data. The total number of statistical signals was modest and does not imply a causal relationship. Rather, data mining results should be used to generate candidate drug-event pairs for rigorous epidemiological studies to evaluate the individual and comparative safety profiles of drugs.

Geographic variation in cardiovascular procedure use among Medicare fee-for-service vs Medicare Advantage beneficiaries.

IMPORTANCE: Little is known about how different financial incentives between Medicare Advantage and Medicare fee-for-service (FFS) reimbursement structures influence use of cardiovascular procedures. OBJECTIVE: To compare regional cardiovascular procedure rates between Medicare Advantage and Medicare FFS beneficiaries. DESIGN, SETTING, AND PARTICIPANTS: Cross-sectional study of Medicare beneficiaries older than 65 years between 2003-2007 comparing rates of coronary angiography, percutaneous coronary intervention (PCI), and coronary artery bypass graft (CABG) surgery across 32 hospital referral regions in 12 states. MAIN OUTCOMES AND MEASURES: Rates of coronary angiography, PCI, and CABG surgery. RESULTS: We evaluated a total of 878,339 Medicare Advantage patients and 5,013,650 Medicare FFS patients. Compared with Medicare FFS patients, Medicare Advantage patients had lower age-, sex-, race-, and income-adjusted procedure rates per 1000 person-years for angiography (16.5 [95% CI, 14.8-18.2] vs 25.9 [95% CI, 24.0-27.9]; P < .001) and PCI (6.8 [95% CI, 6.0-7.6] vs 9.8 [95% CI, 9.0-10.6]; P < .001) but similar rates for CABG surgery (3.1 [95% CI, 2.8-3.5] vs 3.4 [95% CI, 3.1-3.7]; P = .33). There were no significant differences between Medicare Advantage and Medicare FFS patients in the rates per 1000 person-years of urgent angiography (3.9 [95% CI, 3.6-4.2] vs 4.3 [95% CI, 4.0-4.6]; P = .24) or PCI (2.4 [95% CI, 2.2-2.7] vs 2.7 [95% CI, 2.5-2.9]; P = .16). Procedure rates varied widely across hospital referral regions among Medicare Advantage and Medicare FFS patients. For angiography, the rates per 1000 person-years ranged from 9.8 to 40.6 for Medicare Advantage beneficiaries and from 15.7 to 44.3 for Medicare FFS beneficiaries. For PCI, the rates ranged from 3.5 to 16.8 for Medicare Advantage and from 4.7 to 16.1 for Medicare FFS. The rates for CABG surgery ranged from 1.5 to 6.1 for Medicare Advantage and from 2.5 to 6.0 for Medicare FFS. Across regions, we found no statistically significant correlation between Medicare Advantage and Medicare FFS beneficiary utilization for angiography (Spearman r = 0.19, P = .29) and modest correlations for PCI (Spearman r = 0.33, P = .06) and CABG surgery (Spearman r = 0.35, P = .05). Among Medicare Advantage beneficiaries, adjustment for additional cardiac risk factors had little influence on procedure rates. CONCLUSIONS AND RELEVANCE: Although Medicare beneficiaries enrolled in capitated Medicare Advantage programs had lower angiography and PCI procedure rates than those enrolled in Medicare FFS, the degree of geographic variation in procedure rates was substantial among Medicare Advantage beneficiaries and was similar in magnitude to that observed among Medicare FFS beneficiaries.

Early adverse drug event signal detection within population-based health networks using sequential methods: key methodologic considerations.

PURPOSE: Active surveillance of population-based health networks may improve the timeliness of detection of adverse events (AEs). Our objective was to expand our previous signal detection work by investigating the effect on signal detection of alternative study specifications. METHODS: We compared the signal detection performance under various study specifications using historical data from nine health plans involved in the HMO Research Network's Center for Education and Research on Therapeutics (CERT). Five drug-event pairs representing generally accepted associations with an AE and two pairs representing "negative controls" were analyzed. Alternative study specifications related to the definition of incident users and incident AEs were assessed and compared to our previous findings. RESULTS: Relaxing the incident AE exclusion criteria by (1) including members with prior outpatient diagnoses of interest and (2) halving (to 90 days) the time window specified to define incident exposure and diagnoses increased the number of members under surveillance and as a consequence increased the number of exposed days and diagnoses by about 10-20%. The alternative specifications tend to result in earlier signal detection by 10-16 months, a likely consequence of more exposures and events entering the analysis. CONCLUSIONS: This paper provides additional preliminary information related to conducting prospective safety monitoring using health plan data and sequential analytic methods. Our findings support continued investigation of using health plan data and sequential analytic methods as a potentially important contribution to active drug safety surveillance.

Laboratory evaluation of potassium and creatinine among ambulatory patients prescribed spironolactone: are we monitoring for hyperkalemia?

BACKGROUND: Serum potassium and creatinine evaluation is recommended in patients prescribed spironolactone, yet the proportion of ambulatory patients chronically dispensed spironolactone receiving evaluation is not well understood. OBJECTIVE: To estimate the rate of potassium and creatinine evaluation and identify factors associated with conducting these tests among ambulatory patients dispensed spironolactone. METHODS: A retrospective cohort study was designed to evaluate patients at 10 health maintenance organizations with ongoing spironolactone dispensing for one year (N = 2257). Potassium and creatinine evaluation were determined from administrative data. Associations between patient characteristics and laboratory testing were assessed, using logistic regression modeling. RESULTS: Serum creatinine and potassium were evaluated in 72.3% of patients during a 13 month period. The likelihood of potassium and creatinine monitoring was greater among patients who were older (OR 1.28; 95% CI 1.17 to 1.41 per decade of life); male (OR 1.25; 95% CI 1.01 to 1.54); had diabetes (OR 1.63; 95% CI 1.31 to 2.03); received concomitant therapy with angiotensin-converting enzyme inhibitors/angiotensin receptor blockers (OR 2.23; 95% CI 1.74 to 2.87), potassium supplements (OR 1.96; 95% CI 1.51 to 2.54), or digoxin (OR 2.10 95% CI 1.48 to 2.98); or had more outpatient visits (OR 1.31; 95% CI 1.19 to 1.44). Among patients with heart failure (n = 790), factors associated with the incidence of laboratory testing were diabetes (OR 1.64, 95% CI 1.14 to 2.34), outpatient visits (OR 1.20; 95% CI 1.02 to 1.41), and digoxin therapy (OR 2.26; 95% CI 1.38 to 3.69). CONCLUSIONS: Three-fourths of ambulatory patients dispensed spironolactone receive recommended laboratory evaluation, with monitoring more likely to be completed in patients prescribed concomitant therapy with drugs that increase hyperkalemia risk, older patients, and those with diabetes.

Monitoring of drugs with a narrow therapeutic range in ambulatory care.

OBJECTIVES: To describe the proportion of patients receiving drugs with a narrow therapeutic range who lacked serum drug concentration monitoring during a 1-year period of therapy and to identify patient characteristics associated with lack of monitoring. STUDY DESIGN: Retrospective cohort. METHODS: Ambulatory patients (n = 17,748) at 10 health maintenance organizations who were receiving ongoing continuous drug therapy with digoxin, carbamazepine, divalproex sodium, lithium carbonate, lithium citrate, phenobarbital sodium, phenytoin, phenytoin sodium, primidone, quinidine gluconate, quinidine sulfate, procainamide hydrochloride, theophylline, theophylline sodium glycinate, tacrolimus, or cyclosporine for at least 12 months between January 1, 1999, and June 30, 2001, were identified. Serum drug concentration monitoring was assessed from administrative data and from medical record data. RESULTS: Fifty percent or more of patients receiving digoxin, theophylline, procainamide, quinidine, or primidone were not monitored, and 25% to 50% of patients receiving divalproex, carbamazepine, phenobarbital, phenytoin, or tacrolimus were not monitored. Younger age was associated with lack of monitoring for patients prescribed digoxin (adjusted odds ratio, 1.86; 95% confidence interval, 1.39-2.48) and theophylline (adjusted odds ratio, 1.58; 95% confidence interval, 1.23-2.04), while older age was associated with lack of monitoring for patients prescribed carbamazepine (adjusted odds ratio, 0.59; 95% confidence interval, 0.44-0.80) and divalproex (adjusted odds ratio, 0.50; 95% confidence interval, 0.38-0.66). Patients with fewer outpatient visits were also less likely to be monitored (P < .001). CONCLUSIONS: A substantial proportion of ambulatory patients receiving drugs with narrow intervals between doses resulting in beneficial and adverse effects did not have serum drug concentration monitoring during 1 year of use. Clinical implications of this finding need to be evaluated.

Liver and thyroid monitoring in ambulatory patients prescribed amiodarone in 10 HMOs.

BACKGROUND: Amiodarone can cause liver and thyroid toxicity, but little is known about compliance with laboratory tests to evaluate liver and thyroid function among ambulatory patients who are dispensed amiodarone. OBJECTIVES: The primary objective of this study was to identify the proportion of ambulatory patients who had liver aminotransferase and thyroid function tests during amiodarone therapy. Secondary objectives were to (1) describe factors associated with receipt of laboratory tests and (2) determine the accuracy of administrative data for assessing aminotransferase and thyroid function monitoring. METHODS: This retrospective cohort study was conducted at 10 health maintenance organizations (HMOs) for the dates of service from January 1, 1999, through June 30, 2001. Participants included 1,055 patients dispensed amiodarone for at least 180 days within this date range; these patients were not necessarily new starts on amiodarone. Administrative claims data were analyzed to assess the percentage of patients with completed alanine/aspartate aminotransferase and thyroid function tests. Depending on the HMO site, electronic or paper medical records were reviewed to evaluate the validity of administrative claims data. Logistic regression models were used to explore factors associated with receipt of laboratory tests. RESULTS: Both aminotransferase and thyroid function tests were completed in 53.3% of patients within a 210-day follow-up period that included the 180-day period of amiodarone dispensings plus 30 days. Thyroid function, with or without liver function (aminotransferase tests), was assessed in 61.9% of patients, and aminotransferase tests, with or without thyroid function, were assessed in 68.2% of patients. After adjusting for patient characteristics and site, the factor most strongly associated with having both types of laboratory tests evaluated was concomitant therapy with a statin (adjusted odds ratio (OR) 1.55; 95% confidence interval (CI), 1.05-2.29). Other factors associated with having both types of laboratory tests evaluated included the number of outpatient visits in the 6 months before the period of amiodarone dispensings (adjusted OR 1.06; 95% CI, 1.00- 1.13 for each additional 5 visits) and living in a neighborhood where a higher median percentage of people had a high school or higher education (adjusted OR 1.09; 95% CI, 1.00-1.18 for every 10% increase in educational level at the block level). There was no association between monitoring and patient illness severity as measured by the number of comorbid conditions. On the basis of an evaluation of a randomly selected subset of 104 patient records, the sensitivity and specificity of automated data were 94.2% and 85.7% for aminotransferase tests and 83.3% and 81.1% for thyroid function tests, respectively. CONCLUSIONS: Approximately half of ambulatory patients dispensed amiodarone received both recommended laboratory tests for liver and thyroid function. Improved rates of testing for liver aminotransferase and thyroid function are needed for patients who receive amiodarone.

Laboratory safety monitoring of chronic medications in ambulatory care settings.

OBJECTIVE: To evaluate laboratory safety monitoring in patients taking selected chronic prescription drugs. DESIGN: Retrospective study using 1999-2001 claims data to calculate rates of missed laboratory tests (potential laboratory monitoring errors). Eleven drugs/drug groups and 64 laboratory tests were evaluated. SETTING: Two staff/network model health maintenance organizations. PATIENTS: Continuously enrolled health plan members age> or =19 years taking > or =1 chronic medications. MEASUREMENTS AND MAIN RESULTS: Among patients taking chronic medications (N=29,823 in 1999, N=32,423 in 2000, and N=36,811 in 2001), 47.1% in 1999, 45.0% in 2000, and 44.0% in 2001 did not receive > or =1 test recommended for safety monitoring. Taking into account that patients were sometimes missing more than 1 test for a given drug and that patients were frequently taking multiple drugs, the rate of all potential laboratory monitoring errors was 849/1,000 patients/year in 1999, 810/1,000 patients/year in 2000, and 797/1,000 patients/year in 2001. Rates of potential laboratory monitoring errors varied considerably across individual drugs and laboratory tests. CONCLUSIONS: Lapses in laboratory monitoring of patients taking selected chronic medications were common. Further research is needed to determine whether, and to what extent, this failure to monitor patients is associated with adverse clinical outcomes.

Laboratory monitoring of drugs at initiation of therapy in ambulatory care.

BACKGROUND AND OBJECTIVES: Product labeling and published guidelines reflect the importance of monitoring laboratory parameters for drugs with a risk of organ system toxicity or electrolyte imbalance. Limited information exists about adherence to laboratory monitoring recommendations. The objective of this study was to describe laboratory monitoring among ambulatory patients dispensed medications for which laboratory testing is recommended at therapy initiation. DESIGN AND SUBJECTS: We conducted a retrospective cross-sectional analysis of patients in 10 geographically distributed health maintenance organizations who were newly prescribed medications with recommended laboratory test monitoring. The main outcome measure was the proportion of initial drug dispensing without recommended baseline laboratory monitoring for 35 newly initiated drugs or drug classes. RESULTS: One hundred seven thousand, seven hundred sixty-three of 279,354 (39%) initial drug dispensings occurred without recommended laboratory monitoring. Patients without monitoring were younger than patients who had monitoring (median 57 vs 61 years, P<.001). Thirty-two percent of dispensings where a serum creatinine was indicated did not have it evaluated (range across drugs, 12% to 61%); 39% did not have liver function testing (range 10% to 75%); 32% did not have hematologic monitoring (range 9% to 51%); and 34% did not have electrolyte monitoring (range 20% to 62%) (P<.001). CONCLUSIONS: Substantial opportunity exists to improve laboratory monitoring of drugs for which such monitoring is recommended. This study emphasizes the need for research to identify the clinical implications of not conducting recommended laboratory monitoring, existing barriers to monitoring, and methods to improve practice.

Health plan members' views on forgiving medical errors.

BACKGROUND: How patients respond to medical errors may influence how physicians approach disclosure of medical errors, but information on patients' responses is limited. Research is needed on how the circumstances that surround a medical error affect how patients respond. OBJECTIVE: To investigate whether patients' tendency to forgive a physician following a medical error varied under different circumstances. STUDY DESIGN: Cross-sectional survey. METHODS: We mailed a questionnaire to 1500 randomly selected health plan members; the response rate was 66%. Questionnaire items assessed the likelihood of forgiveness following a medical error under 12 circumstances drawn from a review of the literature. RESULTS: Respondents were most likely to forgive a physician if the patient failed to provide complete information (93% would or might forgive) and least likely to forgive if the error was due to efforts to keep costs down (11% would or might forgive). Most respondents would not forgive a physician when the physician was tired or distracted (68%), was incomplete in data collection (76%), lacked knowledge (78%), or failed to follow up (85%). Men were more likely to forgive than women; the most educated respondents were most likely to forgive. CONCLUSIONS: Our findings suggest that patients are not likely to forgive a physician in circumstances in which they suspect incompetence, inattention, or a lack of caring on the part of the physician involved. A more comprehensive understanding of forgiveness and the effect of forgiveness on the physician-patient relationship following a medical error is needed.

Health plan members' views about disclosure of medical errors.

BACKGROUND: Various authorities and national organizations encourage disclosing medical errors, but there is little information on how patients respond to disclosure. OBJECTIVE: To examine how the type of error, severity of adverse clinical outcome, and level of disclosure affect patients' responses to error and disclosure. DESIGN: Mail questionnaire survey (8 versions were developed) varying 3 factors in a completely crossed, randomized, factorial design. Each questionnaire included a vignette describing 1) a medical error (failure to check for penicillin allergy or inadequate monitoring of antiepileptic medication); 2) an associated clinical outcome (life-threatening or less serious); and 3) a physician-patient dialogue, with either full disclosure (acceptance of responsibility and an apology) or nondisclosure (expression of regret without acceptance of responsibility or an apology). SETTING: New England-based health plan. PARTICIPANTS: Random sample of 1500 adult members received the questionnaire, with a 66% response rate. MEASUREMENTS: Likelihood of changing physicians, likelihood of seeking legal advice, ratings of patient satisfaction, trust and emotional reaction in response to a vignette and dialogue, and views on medical error and disclosure. RESULTS: Full disclosure reduced the reported likelihood of changing physicians and increased patient satisfaction, trust, and positive emotional response. Full disclosure reduced the reported likelihood of seeking legal advice in only 1 error-and-outcome vignette. In the other vignettes, the percentage of patients indicating that they would seek legal advice was relatively high even with full disclosure. Almost all respondents (98.8%) wanted to be told of errors, most (83%) favored financial compensation if harm occurred, and few (12.7%) favored compensation if no harm occurred. LIMITATIONS: Since the study was done in the context of a managed care plan in one geographic area, it could not assess whether the results are generalizable to other populations. In addition, it could not determine whether responses to the simulated situations used predict responses to real situations. CONCLUSIONS: Patients will probably respond more favorably to physicians who fully disclose medical errors than to physicians who are less forthright, but the specifics of the case and the severity of the clinical outcome also affect patients' responses. In some circumstances, the desire to seek legal advice may not diminish despite full disclosure.

Developing a computer algorithm to identify epilepsy cases in managed care organizations.

The goal of this study was to develop an algorithm for detecting epilepsy cases in managed care organizations (MCOs). A data set of potential epilepsy cases was constructed from an MCO's administrative data system for all health plan members continuously enrolled in the MCO for at least 1 year within the study period of July 1, 1996 through June 30, 1998. Epilepsy status was determined using medical record review for a sample of 617 cases. The best algorithm for detecting epilepsy cases was developed by examining combinations of diagnosis, diagnostic procedures, and medication use. The best algorithm derived in the exploratory phase was then applied to a new set of data from the same MCO covering the period of July 1, 1998 through June 30, 2000. A stratified sample based on ethnicity and age was drawn from the preliminary algorithm-identified epilepsy cases and non-cases. Medical record review was completed for 644 cases to determine the accuracy of the algorithm. Data from both phases were combined to permit refinement of logistic regression models and to provide more stable estimates of the parameters. The best model used diagnoses and antiepileptic drugs as predictors and had a positive predictive value of 84% (sensitivity 82%, specificity 94%). The best model correctly classified 90% of the cases. A stable algorithm that can be used to identify epilepsy patients within MCOs was developed. Implications for use of the algorithm in other health care settings are discussed.

Management of epilepsy in adults. Diagnosis guidelines.

In this first of two articles on new epilepsy guidelines for primary care physicians, the authors present detailed algorithms for the diagnosis and classification of seizure disorders in adults. They discuss the differentiation between generalized and partial seizures and stress that accurate identification is especially important because the type of seizure determines the appropriate treatment. The second article (page 29) looks at the treatment portion of the new guidelines.

Management of epilepsy in adults. Treatment guidelines.

In this second of two articles on new epilepsy guidelines for primary care physicians, the authors discuss which treatments are the most effective in adults with this disease. They describe the antiepileptic drugs that are currently approved and elucidate the differences between established and newer options. Detailed algorithms cover pharmacotherapy, follow-up, and ongoing maintenance.

Adequacy of glycemic, lipid, and blood pressure management for patients with diabetes in a managed care setting.

OBJECTIVE: We conducted a retrospective study to evaluate the adequacy of glycemic, lipid, and blood pressure (BP) management for diabetic patients in a managed care organization (MCO). RESEARCH DESIGN AND METHODS: Patients aged > or =18 years with diabetes (n=7,114) were retrospectively identified over a 2-year period from the MCO's administrative database based on the Health Plan Employer Data and Information Set 2000 selection criteria using pharmacy, laboratory, and encounter data. Analyses examined demographics and percentages of patients tested and meeting American Diabetes Association goals for HbA1c, lipids, and BP, both overall and for those receiving medication treatment versus no treatment. RESULTS: Testing rates for A1C, LDL cholesterol, and BP were 77, 54, and 95%, respectively. The percentage of patients tested who were at goal were 37% for A1C, 23% for LDL cholesterol, and 41% for systolic BP. Of the patients in our sample, 72% were treated for glycemic control, 64% were treated for BP control, and only 28% were treated for lipid control. Of the patients who received medication treatment, less than one-third were at goal for A1C (29%) and LDL cholesterol (32%), whereas 40% were at goal for systolic BP. CONCLUSIONS: We found that although a large percentage of diabetic patients were tested for A1C, LDL cholesterol, and systolic BP, a much smaller percentage had reached their respective goals. More aggressive glycemic, lipid, and BP management appears to be needed to improve care for these patients.

Measuring patient safety in ambulatory care: potential for identifying medical group drug-drug interaction rates using claims data.

OBJECTIVE: To evaluate the feasibility of using health-plan administrative data to measure potential drug-drug interaction (DDI) rates in the ambulatory setting at the medical-group level and to assess the potential use of DDI rates in performance measurement, quality improvement, and research in patient safety. STUDY DESIGN: We combined administrative and pharmacy claims data from 2 large health plans to calculate the rates at which member users of selected chronic medications were potentially exposed to a second drug known to pose a risk of harmful interactions. METHODS: We divided 44 medication combinations with risk of adverse interactions into those with DDIs of moderate/severe clinical significance and those with DDIs of mild significance. We then calculated yearly rates of potential DDIs in continuously enrolled members aged 19 and older from 1998 through 2001. Rates were calculated for all members, overall base-medication users, and, individual medical groups responsible for their care. RESULTS: The analytic data set included 756 047 patient-years of data and 110 to 123 medical groups per year. During the 4-year interval, one or more unique potential DDIs occurred in 6.2% to 6.7% of base-drug users and 2.0% to 2.3% of all adult health-plan members per year. Medical-group mean user rates were slightly lower (5.33%-5.81%), with wide variance (SD = 2.6%-3.1%) and high stability over time. CONCLUSION: Potential DDI rates calculated from health-plan data have promise for measurement in patient medication safety. This readily available and inexpensive evaluation tool has potential for monitoring, improvement, and research purposes if further studies validate their relationship to actual adverse events.

Impact of a seizure disorder disease management program on patient-reported quality of life.

The objective of this study was to evaluate the impact of a comprehensive, multifaceted disease management program on self-reported quality of life (QOL) for adult patients with epilepsy. The study (1996-2000) employed a quasi-experimental research design in which primary care clinics in a southwestern integrated delivery system were assigned to either the intervention or comparison group. The impact evaluation involved a comparison of responses to a validated QOL survey before and after a disease management intervention for adult health plan members with epilepsy. The intervention consisted of both formal provider training and associated tools and reinforcements as well as direct-to-patient interventions, including a comprehensive education booklet, a seizure diary, a patient education class, and a resource list. Pre-post analysis utilizing paired t-tests was conducted to identify any pre-post differences in QOL for both the intervention and comparison group patients, as measured by the seven specific domains of the epilepsy QOL instrument (QOLIE-31). The intervention group patients showed statistically significant positive changes in two QOL domains: Seizure Worry (p < 0.001) and Emotional Well-being (p < 0.05). One other domain, Overall Quality of Life, showed improvement in the intervention group that approached statistical significance (p < 0.06). There were no statistically significant changes for the comparison group. A well-designed, comprehensive disease management program can improve patient empowerment and coordination of care between the patient and provider, which resulted in an improvement in quality of life, one of the most central patient outcomes in this difficult disease.

Management of osteoporosis in women aged 50 and older with osteoporosis-related fractures in a managed care population.

This study describes the pattern of evaluation and management of osteoporosis in women aged 50 and older following an osteoporosis-related fracture, conducted as a retrospective cohort study using the administrative claims database of a managed care organization. Subjects were women, aged 50 years and older, with at least one osteoporosis-related fracture in the years 1996-1998 who were continuously enrolled in the system's health plan for at least 6 months prior to and post-fracture. Bone mineral density (BMD) testing, diagnosis of osteoporosis, and treatment with any Food and Drug Administration-approved medication for osteoporosis were identified using CPT, ICD-9, and National Drug Codes for the 6-month post-fracture period. There were 658 women with an osteoporosis-related fracture: 189 (29%) hip fractures, 226 (34%) wrist fractures, 127 (19%) vertebral fractures, and 116 (18%) rib fractures. In the post-fracture period, 46 (7%) underwent BMD testing, 153 (23%) had a diagnosis of osteoporosis, and 220 (31%) were treated with a medication approved for the prevention or treatment of osteoporosis. Of the 220 women with medication claims, 124 (56%) were for estrogen, and 96 (44%) were for other antiresorptive agents. Of the 507 women who did not have medication claims during the 6 months prior to the fracture, only 17% had new fills after the fracture. Management of osteoporosis in women aged 50 and older with fractures was inadequate, despite the high risk of subsequent fractures and recommendations that osteoporosis be the presumptive diagnosis. Significant opportunity exists for improvement in assuring post-fracture followup care.

Drug Adverse Event Detection in Health Plan Data Using the Gamma Poisson Shrinker and Comparison to the Tree-based Scan Statistic.

BACKGROUND: Drug adverse event (AE) signal detection using the Gamma Poisson Shrinker (GPS) is commonly applied in spontaneous reporting. AE signal detection using large observational health plan databases can expand medication safety surveillance. METHODS: Using data from nine health plans, we conducted a pilot study to evaluate the implementation and findings of the GPS approach for two antifungal drugs, terbinafine and itraconazole, and two diabetes drugs, pioglitazone and rosiglitazone. We evaluated 1676 diagnosis codes grouped into 183 different clinical concepts and four levels of granularity. Several signaling thresholds were assessed. GPS results were compared to findings from a companion study using the identical analytic dataset but an alternative statistical method-the tree-based scan statistic (TreeScan). RESULTS: We identified 71 statistical signals across two signaling thresholds and two methods, including closely-related signals of overlapping diagnosis definitions. Initial review found that most signals represented known adverse drug reactions or confounding. About 31% of signals met the highest signaling threshold. CONCLUSIONS: The GPS method was successfully applied to observational health plan data in a distributed data environment as a drug safety data mining method. There was substantial concordance between the GPS and TreeScan approaches. Key method implementation decisions relate to defining exposures and outcomes and informed choice of signaling thresholds.

The effectiveness of screening and brief intervention on reducing driving while intoxicated citations.

The purpose of this study was to use retrospective data, including citations for driving while intoxicated (DWI), to assess the long-term effectiveness of a program consisting of Screening and Brief Intervention (SBI) for at-risk alcohol users and its impact on traffic safety. A second objective was to study ethnic differences in response to SBI. During the time period of 1998-1999, LCF Research, together with the Lovelace Health System, participated in the Cutting Back SBI study for at-risk drinkers. A total of 426 subjects exhibiting at-risk drinking behaviors from the New Mexico cohort were examined for the study, including 211 subjects who received a brief counseling intervention and 215 in the no intervention control group. This study examined DWI citations for all 426 subjects during the 5 years following the Cutting Back study. The brief interventions were shown to have had a significant impact on reducing DWI citations for at-risk drinkers, with the added benefit lasting for the 5-year duration of the study. The SBI was found to be most effective at reducing DWI citations for Hispanic at-risk drinkers. Evidence is presented to show that screening to identify at-risk drinkers followed by a brief intervention has a statistically significant lasting impact on improving traffic safety.

Neighborhood socioeconomic status and use of colonoscopy in an insured population--a retrospective cohort study.

BACKGROUND: Low-socioeconomic status (SES) is associated with a higher colorectal cancer (CRC) incidence and mortality. Screening with colonoscopy, the most commonly used test in the US, has been shown to reduce the risk of death from CRC. This study examined if, among insured persons receiving care in integrated healthcare delivery systems, differences exist in colonoscopy use according to neighborhood SES. METHODS: We assembled a retrospective cohort of 100,566 men and women, 50-74 years old, who had been enrolled in one of three US health plans for ≥1 year on January 1, 2000. Subjects were followed until the date of first colonoscopy, date of disenrollment from the health plan, or December 31, 2007, whichever occurred first. We obtained data on colonoscopy use from administrative records. We defined screening colonoscopy as an examination that was not preceded by gastrointestinal conditions in the prior 6-month period. Neighborhood SES was measured using the percentage of households in each subject's census-tract with an income below 1999 federal poverty levels based on 2000 US census data. Analyses, adjusted for demographics and comorbidity index, were performed using Weibull regression models. RESULTS: The average age of the cohort was 60 years and 52.7% were female. During 449,738 person-years of follow-up, fewer subjects in the lowest SES quartile (Q1) compared to the highest quartile (Q4) had any colonoscopy (26.7% vs. 37.1%) or a screening colonoscopy (7.6% vs. 13.3%). In regression analyses, compared to Q4, subjects in Q1 were 16% (adjusted HR = 0.84, 95% CI: 0.80-0.88) less likely to undergo any colonoscopy and 30%(adjusted HR = 0.70, CI: 0.65-0.75) less likely to undergo a screening colonoscopy. CONCLUSION: People in lower-SES neighborhoods are less likely to undergo a colonoscopy, even among insured subjects receiving care in integrated healthcare systems. Removing health insurance barriers alone is unlikely to eliminate disparities in colonoscopy use.