Individuals Eligible for Lung Cancer Screening Less Likely to Receive Screening When Enrolled in Health Plans With Deductibles.

BACKGROUND: In 2015, the Centers for Medicare & Medicaid Services and commercial insurance plans began covering lung cancer screening (LCS) without patient cost-sharing for all plans. We explore the impact of enrolling into a deductible plan on the utilization of LCS services despite having no out-of-pocket cost requirement. METHODS: This retrospective study analyzed data from the Population-based Research to Optimize the Screening Process Lung Consortium. Our cohort included non-Medicare LCS-eligible individuals enrolled in managed care organizations between February 5, 2015, and February 28, 2019. We estimate a series of sequential logistic regression models examining utilization across the sequence of events required for baseline LCS. We report the marginal effects of enrollment into deductible plans compared with enrollment in no-deductible plans. RESULTS: The total effect of deductible plan enrollment was a 1.8 percentage-point (PP) decrease in baseline LCS. Sequential logistic regression results that explore each transition separately indicate deductible plan enrollment was associated with a 4.3 PP decrease in receipt of clinician visit, a 1.7 PP decrease in receipt of LCS order, and a 7.0 PP decrease in receipt of baseline LCS. Reductions persisted across all observable races and ethnicities. CONCLUSIONS: These findings suggest individuals enrolled in deductible plans are more likely to forgo preventive LCS services despite requiring no out-of-pocket costs. This result may indicate that increased cost-sharing is associated with suboptimal choices to forgo recommended LCS. Alternatively, this effect may indicate individuals enrolling into deductible plans prefer less health care utilization. Patient outreach interventions at the health plan level may improve LCS.

Patterns of Medical Care Cost by Service Type for Patients With Recurrent and De Novo Advanced Cancer.

OBJECTIVES: There is limited knowledge about the cost patterns of patients who receive a diagnosis of de novo and recurrent advanced cancers in the United States. METHODS: Data on patients who received a diagnosis of de novo stage IV or recurrent breast, colorectal, or lung cancer between 2000 and 2012 from 3 integrated health systems were used to estimate average annual costs for total, ambulatory, inpatient, medication, and other services during (1) 12 months preceding de novo or recurrent diagnosis (preindex) and (2) diagnosis month through 11 months after (postindex), from the payer perspective. Generalized linear regression models estimated costs adjusting for patient and clinical factors. RESULTS: Patients who developed a recurrence <1 year after their initial cancer diagnosis had significantly higher total costs in the preindex period than those with recurrence ≥1 year after initial diagnosis and those with de novo stage IV disease across all cancers (all P < .05). Patients with de novo stage IV breast and colorectal cancer had significantly higher total costs in the postindex period than patients with cancer recurrent in <1 year and ≥1 year (all P < .05), respectively. Patients in de novo stage IV and those with recurrence in ≥1 year experienced significantly higher postindex costs than the preindex period (all P < .001). CONCLUSIONS: Our findings reveal distinct cost patterns between patients with de novo stage IV, recurrent <1-year, and recurrent ≥1-year cancer, suggesting unique care trajectories that may influence resource use and planning. Future cost studies among patients with advanced cancer should account for de novo versus recurrent diagnoses and timing of recurrence to obtain estimates that accurately reflect these care pattern complexities.

Return of Research-Related Genetic Test Results and Genetic Discrimination Concerns: Facilitators and Barriers of Genetic Research Participation in Diverse Groups.

BACKGROUND: Most genetics studies lack the diversity necessary to ensure that all groups benefit from genetic research. OBJECTIVES: To explore facilitators and barriers to genetic research participation. METHODS: We conducted a survey on genetics in research and healthcare from November 15, 2017 to February 28, 2018 among adult Kaiser Permanente (KP) members who had been invited to participate in the KP biobank (KP Research Bank). We used logistic regression to calculate adjusted odds ratios (ORs) and 95% confidence intervals (CIs) comparing the willingness to participate in genetic research under different return of results scenarios and genetic discrimination concerns between groups, according to their demographic characteristics. RESULTS: A total of 57,331 KP members were invited to participate, and 10,369 completed the survey (18% response rate). Respondents were 65% female, 44% non-Hispanic White (NH White), 22% Asian/Native Hawaiian or other Pacific Islander (Asian/PI), 19% non-Hispanic Black (NH Black), and 16% Hispanic. Respondents willing to participate in genetic research ranged from 22% with no results returned to 87% if health-related genetic results were returned. We also found variation by race/ethnicity; when no results were to be returned, Asian/PIs, Hispanics, and NH Blacks were less likely to want to participate than NH Whites (p < 0.05). However, when results were returned, disparities in the willingness to participate disappeared for NH Blacks and Hispanics. Genetic discrimination concerns were more prevalent in Asian/PIs, Hispanics, and NH Blacks than in NH Whites (p < 0.05). CONCLUSIONS: Policies that prohibit the return of results and do not address genetic discrimination concerns may contribute to a greater underrepresentation of diverse groups in genetic research.

Demographic differences in the utilization of clinical and direct-to-consumer genetic testing.

Genetic testing has increased over the last decade due to growth in the number of clinical and direct-to-consumer (DTC) tests. However, there is uncertainty about how increased DTC genetic testing affects disparities. Between November 2017 and February 2018, a nationwide electronic survey on experiences with genetic testing was conducted among adult Kaiser Permanente members. Logistic regression was used to calculate adjusted odds ratios and 95% confidence intervals comparing receipt of clinical and DTC genetic testing between groups by race and ethnicity. Invitations were sent to 57,331 members, and 10,369 surveys were completed. 22% of respondents had received genetic testing (17% DTC and 5% provider-ordered). Non-Hispanic Whites were more likely than other groups to have clinical genetic testing but were similar to Hispanics and non-Hispanic Blacks in rates of DTC genetic testing. Among those who received any health-related genetic test, 10% reported abnormal results. Of these, non-Hispanic Whites were more likely than other racial/ethnic groups to speak to a medical professional about abnormal results. Results suggest that racial/ethnic disparities in the use of clinical genetic services persist. Additional research is needed to identify lessons learned from DTC genetic testing that may increase equity in the use of clinical genetic services.

Melanoma incidence, recurrence, and mortality in an integrated healthcare system: A retrospective cohort study.

BACKGROUND: Numerous studies have examined melanoma incidence and survival, but studies on melanoma recurrence are limited. We examined melanoma incidence, recurrence, and mortality among members of Kaiser Permanente Colorado (KPCO) between January 1, 2000 and December 31, 2015. METHODS: Age-adjusted incidence rates were computed to examine trends among KPCO members aged 21 years and older. Cox proportional hazards models were used to examine factors associated with recurrence and mortality. RESULTS: Our cohort included 1931 cases of invasive melanoma. Incidence rates increased over time and were higher than SEER rates; however, the increase was limited to early stage disease. In multivariable models, stage at initial diagnosis, gender, and age were associated with melanoma recurrence. Men were more likely to have a recurrence than women (adjusted hazard ratio [HR]: 1.70, 95% confidence interval [CI]: 1.19-2.43), and for each decade of increasing age, the adjusted HR = 1.20 (95% CI: 1.06-1.37). Factors associated with all-cause mortality included stage (HR = 12.87, 95% CI: 6.63-24.99, for stage IV vs stage I), male gender (HR = 1.42, 95% CI: 1.12-1.79), older age at diagnosis, lower socioeconomic status, and comorbidity index. For melanoma-specific mortality, results were similar, with one exception: age was not associated with melanoma-specific death (HR = 1.09, 95% CI: 0.94-1.25, P = 0.253). CONCLUSIONS: Data derived from an insured patient population, such as KPCO, have the potential to enhance our understanding of emerging trends in melanoma. This is the first population-based study in the United States to examine patient characteristics associated with risk of recurrence. Men have an increased risk of both recurrence and death, and thus may benefit from more intensive follow-up than women.

Spending for Advanced Cancer Diagnoses: Comparing Recurrent Versus De Novo Stage IV Disease.

PURPOSE: Spending for patients with advanced cancer is substantial. Past efforts to characterize this spending usually have not included patients with recurrence (who may differ from those with de novo stage IV disease) or described which services drive spending. METHODS: Using SEER-Medicare data from 2008 to 2013, we identified patients with breast, colorectal, and lung cancer with either de novo stage IV or recurrent advanced cancer. Mean spending/patient/month (2012 US dollars) was estimated from 12 months before to 11 months after diagnosis for all services and by the type of service. We describe the absolute difference in mean monthly spending for de novo versus recurrent patients, and we estimate differences after controlling for type of advanced cancer, year of diagnosis, age, sex, comorbidity, and other factors. RESULTS: We identified 54,982 patients with advanced cancer. Before diagnosis, mean monthly spending was higher for recurrent patients (absolute difference: breast, $1,412; colorectal, $3,002; lung, $2,805; all P < .001), whereas after the diagnosis, it was higher for de novo patients (absolute difference: breast, $2,443; colorectal, $4,844; lung, $2,356; all P < .001). Spending differences were driven by inpatient, physician, and hospice services. Across the 2-year period around the advanced cancer diagnosis, adjusted mean monthly spending was higher for de novo versus recurrent patients (spending ratio: breast, 2.39 [95% CI, 2.05 to 2.77]; colorectal, 2.64 [95% CI, 2.31 to 3.01]; lung, 1.46 [95% CI, 1.30 to 1.65]). CONCLUSION: Spending for de novo cancer was greater than spending for recurrent advanced cancer. Understanding the patterns and drivers of spending is necessary to design alternative payment models and to improve value.

Medical Care Costs for Recurrent versus De Novo Stage IV Cancer by Age at Diagnosis.

OBJECTIVE: To address the knowledge gap regarding medical care costs for advanced cancer patients, we compared costs for recurrent versus de novo stage IV breast, colorectal, and lung cancer patients. DATA SOURCES/STUDY SETTING: Virtual Data Warehouse (VDW) information from three Kaiser Permanente regions: Colorado, Northwest, and Washington. STUDY DESIGN: We identified patients aged ≥21 with de novo or recurrent breast (nde novo  = 352; nrecurrent  = 765), colorectal (nde novo  = 1,072; nrecurrent  = 542), and lung (nde novo  = 4,041; nrecurrent  = 340) cancers diagnosed 2000-2012. We estimated average total monthly and annual costs in the 12 months preceding, month of, and 12 months following the index de novo/recurrence date, stratified by age at diagnosis (<65, ≥65). Generalized linear repeated-measures models controlled for demographics and comorbidity. PRINCIPAL FINDINGS: In the pre-index period, monthly costs were higher for recurrent than for de novo breast (<65: +$2,431; ≥65: +$1,360), colorectal (<65: +$3,219; ≥65: +$2,247), and lung cancer (<65: +$3,086; ≥65: +$2,260) patients. Conversely, during the index and post-index periods, costs were higher for de novo patients. Average total annual pre-index costs were five- to ninefold higher for recurrent versus de novo patients <65. CONCLUSIONS: Cost differences by type of advanced cancer and by age suggest heterogeneous patterns of care that merit further investigation.

Development, Validation, and Dissemination of a Breast Cancer Recurrence Detection and Timing Informatics Algorithm.

Background: This study developed, validated, and disseminated a generalizable informatics algorithm for detecting breast cancer recurrence and timing using a gold standard measure of recurrence coupled with data derived from a readily available common data model that pools health insurance claims and electronic health records data. Methods: The algorithm has two parts: to detect the presence of recurrence and to estimate the timing of recurrence. The primary data source was the Cancer Research Network Virtual Data Warehouse (VDW). Sixteen potential indicators of recurrence were considered for model development. The final recurrence detection and timing models were determined, respectively, by maximizing the area under the ROC curve (AUROC) and minimizing average absolute error. Detection and timing algorithms were validated using VDW data in comparison with a gold standard recurrence capture from a third site in which recurrences were validated through chart review. Performance of this algorithm, stratified by stage at diagnosis, was compared with other published algorithms. All statistical tests were two-sided. Results: Detection model AUROCs were 0.939 (95% confidence interval [CI] = 0.917 to 0.955) in the training data set (n = 3370) and 0.956 (95% CI = 0.944 to 0.971) and 0.900 (95% CI = 0.872 to 0.928), respectively, in the two validation data sets (n = 3370 and 3961, respectively). Timing models yielded average absolute prediction errors of 12.6% (95% CI = 10.5% to 14.5%) in the training data and 11.7% (95% CI = 9.9% to 13.5%) and 10.8% (95% CI = 9.6% to 12.2%) in the validation data sets, respectively, and were statistically significantly lower by 12.6% (95% CI = 8.8% to 16.5%, P < .001) than those estimated using previously reported timing algorithms. Similar covariates were included in both detection and timing algorithms but differed substantially from previous studies. Conclusions: Valid and reliable detection of recurrence using data derived from electronic medical records and insurance claims is feasible. These tools will enable extensive, novel research on quality, effectiveness, and outcomes for breast cancer patients and those who develop recurrence.

Determining the Time of Cancer Recurrence Using Claims or Electronic Medical Record Data.

PURPOSE: Data from claims and electronic medical records (EMRs) are frequently used to identify clinical events (eg, cancer diagnosis, stroke). However, accurately determining the time of clinical events can be challenging, and the methods used to generate time estimates are underdeveloped. We sought to develop an approach to determine the time of a clinical event-cancer recurrence-using high-dimensional longitudinal structured data. METHODS: Manual chart abstraction provided information regarding the actual time of cancer recurrence. These data were linked to claims from Medicare or structured EMR data from the Cancer Research Network, which were used to determine time of recurrence for patients with lung or colorectal cancer. We analyzed the longitudinal profile of codes that could help determine the time of recurrence, adjusted for systematic differences between code dates and recurrence dates, and integrated time estimates from different codes to empirically derive an optimal algorithm. RESULTS: We identified twelve code groups that could help determine the time of recurrence. Using claims data for patients with lung cancer, the optimal algorithm consisted of three code groups and provided an average prediction error of 4.8 months. Using EMR data or applying this approach to patients with colorectal cancer yielded similar results. CONCLUSION: Time estimates were improved by selecting codes not necessarily the same as those used to identify recurrence, combining time estimates from multiple code groups, and adjusting for systematic bias between code dates and recurrence dates. Improving the accuracy of time estimates for clinical events can facilitate research, quality measurement, and process improvement.

The influence of deductible health plans on receipt of the human papillomavirus vaccine series.

PURPOSE: To evaluate whether enrollment in deductible health plans (DHP) with higher patient cost-sharing requirements than traditional health maintenance organization plans (HMP) decreased initiation and completion of the human papillomavirus (HPV) vaccine series recommended for prevention of cervical cancer. METHODS: This was a retrospective observational study of 9- to 26-year-old females at Kaiser Permanente Georgia and Kaiser Permanente Colorado who were HPV vaccine naive at time of enrollment in a self-pay DHP or HMP in 2007. Estimates of rates of initiation and completion of the HPV vaccine series from plan enrollment in 2007 through December 2009 were obtained using Cox proportional hazards regressions (accounting for censoring) on samples matched on the propensity to enroll in a DHP versus HMP. RESULTS: Initiation of the HPV vaccine series was 22.2% and 24.4% in the DHP and HMP groups, respectively, at Kaiser Permanente Georgia; completion was 12.3% and 14.4% in the DHP and HMP groups, respectively. Human papillomavirus vaccine series initiation was higher at Kaiser Permanente Colorado, but completion was lower. In the Cox proportional hazards regressions, rates of initiation and completion of the HPV vaccine series did not differ significantly (p ≤ .05) by plan type (DHP vs. HMP) at both sites. The primary care visit rate included in these regressions had a significant, positive association with initiation and completion of the HPV vaccine series. CONCLUSIONS: Enrollment in a DHP versus an HMP did not directly affect initiation or completion of the HPV vaccine series among age-eligible females. Independent of plan type, more frequent primary care visits increased initiation and completion rates.

Increased risk of bleeding in patients on clopidogrel therapy after drug-eluting stents implantation: insights from the HMO Research Network-Stent Registry (HMORN-stent).

BACKGROUND: Studies suggest that extended clopidogrel use after drug-eluting stent (DES) implantation may decrease the risk of myocardial infarction (MI) and death. Little is known about the competing risk of bleeding from clopidogrel in "real world" clinical practice. METHODS AND RESULTS: We studied 7689 patients undergoing drug-eluting stent implantation enrolled in the HMO Research Network-Stent Registry between 2004 and 2007. Patients were analyzed in 6-month intervals for the occurrence of major bleeding, MI, and death. Clopidogrel use was determined by pharmacy dispensing data. Regression models assessed the association between clopidogrel use and outcomes. Overall, 3603 patients (49.1%) received clopidogrel for >6 months. During a mean follow-up of 418 days (SD, +/-168 days), 217 (2.9%) patients died, 279 (3.7%) had a MI, and 271 (3.6%) had major bleeding. After adjustment, patients on clopidogrel therapy were associated with increased major bleeding in all time intervals (0 to 6 months: relative risk (RR)=2.70, 95% CI=1.41 to 5.19; 7 to 12 months: RR=1.71, 95% CI=1.05 to 2.79; 13 to 18 months: RR=2.34, 95% CI=1.26 to 4.34), compared with patients off clopidogrel. Clopidogrel use was also associated with decreased risk of MI for all time intervals (0 to 6 months: RR=0.52, 95% CI=0.36 to 0.77; 7 to 12 months: RR=0.46, 95% CI=0.30 to 0.70; 13 to 18 months: RR=0.53, 95% CI=0.29 to 0.99) and decreased death in the 7 to 12 month interval (RR=0.50, 95% CI=0.30 to 0.83). CONCLUSIONS: Clopidogrel use was associated with increased major bleeding and decreased MI persisting to 18 months. Bleeding risks on clopidogrel therapy deserve consideration in the ongoing debate regarding optimal clopidogrel duration after PCI.

Delays in filling clopidogrel prescription after hospital discharge and adverse outcomes after drug-eluting stent implantation: implications for transitions of care.

BACKGROUND: Adjuvant clopidogrel therapy is essential after drug-eluting stent (DES) implantation. The frequency with which patients delay filling a clopidogrel prescription after DES implantation and the association of this delay with adverse outcomes is unknown. METHODS AND RESULTS: This was a retrospective cohort study of patients discharged after DES implantation from 3 large integrated health care systems. Filling a clopidogrel prescription was based on pharmacy dispensing data. The primary end point was all-cause mortality or myocardial infarction (MI). Of 7402 patients discharged after DES implantation, 16% (n=1210) did not fill a clopidogrel prescription on day of discharge and the median time delay was 3 days (interquartile range, 1 to 23 days). Compared with patients filling clopidogrel on day of discharge, patients with any delay in filling clopidogrel had higher death/MI rates during follow-up (14.2% versus 7.9%; P<0.001). In multivariable analysis, patients with any delay had increased risk of death/MI (hazard ratio, 1.53; 95% confidence interval, 1.25 to 1.87). Patients with any delay remained at increased risk of adverse outcomes when the delay cutoff was changed to >1, >3, or >5 days after discharge. Factors associated with delay included older age, prior MI, diabetes, renal failure, prior revascularization, cardiogenic shock, in-hospital bleeding, and clopidogrel use within 24 hours of admission. CONCLUSIONS: One in 6 patients delay filling their index clopidogrel prescription after hospital discharge after DES implantation. This delay was associated with increased risk of adverse outcomes and highlights the importance of the transition period from hospital discharge to outpatient setting as a potential opportunity to improve care delivery and patient outcomes.

Identifying and oversampling Hispanics by the Passel-Word surname list for enrollment in a web-based nutritional intervention.

OBJECTIVE: To describe the enrollment rates and characteristics of Hispanics and non-Hispanics from Kaiser Permanente Colorado invited to participate in a web-based intervention promoting increased fruit and vegetable consumption. DESIGN: Hispanics were identified by the Passel-Word Spanish surname list. Characteristics associated with the likelihood of enrollment overall and by ethnicity were examined by logistic regression. RESULTS: A total of 174 (6.1%) probable Hispanics and 340 probable non-Hispanics (11.8%) enrolled. Hispanics were 48% less likely to enroll than non-Hispanics, females were almost four times as likely to enroll as males, and those living in a census tract associated with higher income levels were 41% more likely to enroll than other income groups. Among Hispanics, females were 87% more likely to enroll than males and those living in a census tract associated with higher income levels were 62% more likely to enroll than other income groups. Among non-Hispanics, the odds for enrolling increased 14% for each decade increase of age, females were 43% more likely to enroll than males and those living in a census tract associated with higher income levels were 68% more likely to enroll than those in other income groups. CONCLUSION: Identifying Hispanics through surname for oversampling can be successful in terms of sampling yield and accuracy. However, our results suggest that Hispanics are less likely to enroll in a web-based nutritional intervention. Additional research is needed to identify methods of attracting more Hispanic subjects to these kinds of interventions.

Recruitment to a randomized web-based nutritional intervention trial: characteristics of participants compared to non-participants.

BACKGROUND: Web-based behavioral programs efficiently disseminate health information to a broad population, and online tailoring may increase their effectiveness. While the number of Internet-based behavioral interventions has grown in the last several years, additional information is needed to understand the characteristics of subjects who enroll in these interventions, relative to those subjects who are invited to enroll. OBJECTIVE: The aim of the study was to compare the characteristics of participants who enrolled in an online dietary intervention trial (MENU) with those who were invited but chose not to participate, in order to better understand how these groups differ. METHODS: The MENU trial was conducted among five health plans participating in the HMO Cancer Research Network in collaboration with the University of Michigan Center for Health Communication Research. Approximately 6000 health plan members per site, between the ages of 21 and 65, and stratified by gender with oversampling of minority populations, were randomly selected for recruitment and were mailed an invitation letter containing website information and a US$2 bill with the promise of US$20 for completing follow-up surveys. Administrative and area-based data using geocoding along with baseline survey data were used to compare invitees (HMO members sent the introductory letter), responders (those who entered a study ID on the website), and enrollees (those who completed the enrollment process). Generalized estimating equation multivariate and logistic regression models were used to assess predictors of response and enrollment. RESULTS: Of 28,460 members invited to participate, 4270 (15.0%) accessed the website. Of the eligible responders, 2540 (8.9%) completed the consent form and baseline survey and were enrolled and randomized. The odds of responding were 10% lower for every decade of increased age (P < .001), while the likelihood of enrolling was 10% higher for every decade increase in age (P < .001). Women were more likely to respond and to enroll (P < .001). Those living in a census tract associated with higher education levels were more likely to respond and enroll, as well as those residing in tracts with higher income (P < .001). With a 22% (n = 566) enrollment rate for African Americans and 8% (n = 192) for Hispanics, the enrolled sample was more racially and ethnically diverse than the background sampling frame. CONCLUSIONS: Relative to members invited to participate in the Internet-based intervention, those who enrolled were more likely to be older and live in census tracts associated with higher socioeconomic status. While oversampling of minority health plan members generated an enrolled sample that was more racially and ethnically diverse than the overall health plan population, additional research is needed to better understand methods that will expand the penetration of Internet interventions into more socioeconomically diverse populations. TRIAL REGISTRATION: Clinicaltrials.gov NCT00169312; http://clinicaltrials.gov/ct2/show/NCT00169312 (Archived by WebCite at http://www.webcitation.org/5jB50xSfU).

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.

Warfarin monitoring in ambulatory older individuals receiving antimicrobial therapy.

STUDY OBJECTIVE: To determine the frequency of monitoring of international normalized ratio (INR) within 14 days of coprescription of warfarin and antimicrobial therapy and to evaluate differences in INR monitoring among antimicrobials. DESIGN: Retrospective cohort study. SETTING: Group model health maintenance organization. SUBJECTS: Patients aged 65 years or older who were taking warfarin and an antimicrobial agent. MEASUREMENTS AND MAIN RESULTS: Patients who received dispensings of both warfarin and an antimicrobial agent were identified. We found 2959 coprescribing instances in 1816 patients. The INR values were obtained for 2267 (77%) coprescribing situations within 14 days. Monitoring occurred more frequently (p<0.001) when warfarin was coprescribed with fluoroquinolones (641 [85%] of 755 situations), metronidazole (59 [81%] of 73), tetracyclines (274 [80%] of 341), or macrolides (201 [83%] of 243) than when warfarin was coprescribed with sulfonamides (35 [66%] of 53), penicillins (604 [71%] of 856), or cephalosporins (419 [71%] of 591). Among monitored patients, a higher proportion of monitoring (p<0.001) occurred within 7 days for patients prescribed antifungals (87%), fluoroquinolones (88%), tetracyclines (82%), metronidazole (86%), sulfonamides (86%), or macrolides (85%) than for patients prescribed cephalosporins (68%) or penicillins (75%). CONCLUSION: Most older patients coprescribed warfarin and an antimicrobial in our organization had INR monitoring within 7 days. This is consistent with appropriate practice to manage a risk of clinically important drug-drug interaction between an antimicrobial agent and warfarin. Prospective identification of patients requiring INR monitoring after coprescription of interacting drugs by using merged administrative pharmacy and laboratory data should be further evaluated as a tool to improve clinical outcomes.

Low myopathy rates associated with statins as monotherapy or combination therapy with interacting drugs in a group model health maintenance organization.

STUDY OBJECTIVE: Because the risk for myopathy increases when 3-hydroxy-3-methylglutaryl coenzyme A inhibitors (statins) are used with other agents known to inhibit cytochrome P450 3A4 in patients with dyslipidemia, we sought to quantify this risk in a diverse, real-world sample of patients receiving statin therapy. DESIGN: Retrospective chart review. SETTING: Kaiser Permanente Colorado (KPCO), a group model health maintenance organization with approximately 360,000 members. PATIENTS: Four hundred sixty-eight patients who were identified as having a diagnosis of myopathy over a 4-year period using KPCO computerized data systems. MEASUREMENTS AND MAIN RESULTS: Medical records were reviewed to confirm myopathy cases associated with statin therapy. Of the 468 patients, 61 had received statin therapy before their diagnosis, and 41 (67%) of these patients had confirmed myopathy (documented creatine kinase level>or=1000 IU/L). The prevalence of myopathy was 0.12% with statin monotherapy and 0.22% with statins in combination with interacting drugs. Only 17 of the 41 (41%) patients had confirmed myopathy with no other plausible clinical explanation, such as a muscle injury. Increased risk of myopathy associated with statin therapy in combination with interacting drugs approached statistical significance (p=0.052) but was of minimal clinical significance. CONCLUSION: The prevalence of confirmed myopathy in patients receiving statin therapy is low (<1%). Combining statin therapy with interacting drugs (e.g., fibrates) was not associated with a clinically important increase in the prevalence of myopathy. The risk of developing myopathy during statin therapy is outweighed by the benefits derived from the therapeutic effects of the therapy.