Jacob Abarca

Pharmacist workload and pharmacy characteristics associated with the dispensing of potentially clinically important drug-drug interactions

Background:Drug-drug interactions (DDIs) are preventable medical errors, yet exposure to DDIs continues despite systems that are designed to prevent such exposures. The purpose of this study was to examine pharmacy characteristics that may be associated with dispensed potential DDIs. Methods:This study combined survey data from community pharmacies in 18 metropolitan statistical areas with pharmacy claims submitted to 4 pharmacy benefit managers (PBMs) over a 3-month period from January 1, 2003 to March 31, 2003. Pharmacy characteristics of interest included prescription volume, the number of full-time equivalent pharmacists and pharmacy staff, computer software programs, and the ability to modify those programs with respect to DDI alerts, the use of technologies to assist in receiving, filling and dispensing medication orders, and prescription volume. The dependent variable in this study was the rate of dispensed medications that may interact. Results:A total of 672 pharmacies were included in the analysis. On average (±SD), the respondents filled 1375 ± 691 prescriptions per week, submitted 17,948 ± 23,889 pharmacy claims to the participating PBMs, had 1.2 ± 0.3 full-time equivalent pharmacists per hour open, and 545 (81%) were affiliated with a chain drug store organization. Factors significantly related to an increased risk of dispensing a potential DDI included pharmacist workload (odds ratio [OR] 1.03; 95% confidence interval [CI] 1.028–1.048), pharmacy staffing (OR 1.10; 95% CI: 1.09–1.11), and various technologies (eg, sophisticated telephone systems, internet receipt of orders, and refill requests) that assist with order processing, and the ability to modify DDI alert-screening sensitivity and detailed pharmacological information about DDIs. Conclusions:This study found that there was an increase in the risk of dispensing a potential DDI with higher pharmacist and pharmacy workload, use of specific automation, and dispensing software programs providing alerts and clinical information.

Prescribers' knowledge of and sources of information for potential drug-drug interactions: a postal survey of US prescribers.

AbstractBackground: Given the high prevalence of medication use in the US, the risk of drug-drug interactions (DDIs) and potential for patient harm is of concern. Despite the rise in technologies to identify potential DDIs, the ability of physicians and other prescribers to recognize potential DDIs is essential to reduce their occurrence. The objectives of this study were to assess prescribers’ ability to recognize potential clinically significant DDIs and to examine the sources of information they use to identify potential DDIs and prescribers’ opinions on the usefulness of various DDI information sources. Methods: A postal questionnaire was developed to assess prescriber knowledge of medications that may interact and prescribers’ usual sources of DDI information. Recipients were asked to classify 14 drug pairs as ‘contraindicated’, ‘may be used together but with monitoring’ or ‘no interaction’. A response option of ‘not sure’ was also provided. The questionnaires were sent to a national sample of 12 500 prescribers based on past history of prescribing drugs associated with known potential for DDI, who were identified using data from a pharmacy benefit manager covering over 50 million individuals. Results: Usable questionnaires were obtained from 950 prescribers. The percentage of prescribers who correctly classified specific drug pairs ranged from 18.2% for warfarin and cimetidine to 81.2% for paracetamol (acetaminophen) with codeine and amoxicillin, with 42.7% of all combinations classified correctly. The number of drug pairs correctly classified by the prescribers ranged from 0 to 13. For half of the drug pairs over one-third of the respondents answered ‘not sure’; among those drug pairs, two were contraindicated. When asked what source was used to learn more about a potential DDI, a quarter of the prescribers reported using personal digital assistants and another quarter used printed material. The majority of the prescribers (68.4%) reported that they were usually informed by pharmacists about their patients’ potential exposure to DDIs. Compared with the prescribers who used other sources, those who used computerized DDI alerts as their usual source of DDI information consistently gave a lower rating score to the five statements that assessed the usefulness of the information. Conclusion: This study suggests that prescribers’ knowledge of potential clinically significant DDIs is generally poor. These findings are supported by other research and emphasize the need to develop systems that alert prescribers about potential interactions that are clinically relevant. Physicians most commonly reported learning about potential DDIs from pharmacists, suggesting further work is needed to improve the drug-prescribing process to identify potential safety issues earlier in the medication use process.

Pharmacologic Management of Constipation in the Critically Ill Patient

Study Objective. To compare the effectiveness of common laxatives in producing a bowel movement in patients admitted to a medical intensive care unit (MICU).

Gender and Age Differences in Medications Dispensed from a National Chain Drugstore

OBJECTIVES Our objective was to compare sex and age differences in the medications dispensed in pharmacies from a large national drugstore chain. METHODS Using a list for the 200 most commonly prescribed medicines, we assessed prescriptions dispensed by a large national chain drug store over 1 year (2002-2003). The analysis used U.S. census data adjusted for the population by sex and age and weighted by the number of pharmacies per state. Results are reported as an odds ratio (OR) of prescriptions dispensed to females and males. RESULTS Under age 18, 24 drug classes were dispensed more commonly to females (OR > 1) and 18 drug classes more commonly to males (OR < 1). In the 18-24 age group, 48 of 53 drug classes were dispensed more frequently to females. Across other adult groups, females were dispensed more medications than males for 156 of 180 medications. There was greater dispensing to females of antibiotics (OR = 1.74, 95% confidence interval [CI] 1.74-1.74), analgesics (OR = 1.70, 95% CI 1.70-1.70), antihistamines and sympathomimetics (OR = 1.46, 95% CI 1.45-1.46), benzodiazapines (OR = 2.08, 95% CI 2.07-2.08), antidepressants (OR = 2.40, 95% CI 2.39-2.40), diuretics (OR = 1.9328, 95% CI 1.93-1.94), and thyroid drugs (OR = 4.80, 95% CI 4.78-4.82). However, males had higher dispensing of antianginal drugs (OR = 0.84, 95% CI 0.83-0.85), anticoagulants (OR = 0.89, 95% CI 0.88-0.90), glycosides (OR = 0.80, 95% CI 0.79-0.81), and antihypertensives (OR = 0.91, 95% CI 0.91-0.91). More females were dispensed propoxyphene with acetaminophen (OR = 2.23, 95% CI 2.23-2.24), which has been associated with adverse outcomes (hospitalizations, emergency department visits, and deaths). CONCLUSIONS Females, especially during the reproductive years, are dispensed more medications than males.

Angiotensin‐Converting Enzyme Inhibitor Therapy in Patients with Heart Failure Enrolled in a Managed Care Organization: Effect on Costs and Probability of Hospitalization

Study Objective. To evaluate the effect of angiotensin‐converting enzyme (ACE) inhibitor therapy on risk of hospitalization and resource utilization in patients with heart failure enrolled in a managed care organization.

Incremental Effects of Concurrent Pharmacotherapeutic Regimens for Heart Failure on Hospitalizations and Costs

BACKGROUND Inappropriate medication use in patients with heart failure (HF) presents challenges in providing optimal, evidence-based care. OBJECTIVE To evaluate the incremental differences of concurrent and persistent use of angiotensin-converting enzyme (ACE) inhibitors, β-blockers, loop diuretics, and digoxin on the one-year, all-cause risk of hospitalization and total healthcare costs associated with treatment of HF in patients enrolled in a managed care organization within the US. METHODS A retrospective database analysis was conducted spanning from January 1, 1997, to December 31, 1999. Multivariate regression methods were used to examine the association between treatment regimens and hospitalizations or costs after controlling for patient demographics and risk factors. RESULTS Of the 1903 patients meeting inclusion criteria, 32.3% (n = 615) received none of the 4 HF agents studied and were associated with a 2.5 times greater risk (p ≤ 0.001) of hospitalization and 43.6% higher (p ≤ 0.001) total costs compared with all other patients with HF. Comparatively, 13.9% (n = 264) utilized the HF medications investigated for at least 6 months. Of those with persistent use of ≥3 agents, approximate decreases in hospitalizations were noted of 80% (p ≤ 0.001) and total costs of 70% (p ≤ 0.001) relative to patients receiving no HF therapy. CONCLUSIONS A substantial portion of patients with HF may be receiving suboptimal pharmacotherapeutic care in real-world practice settings, potentially incurring large increases in hospitalizations and total costs. Quality improvement initiatives should seek to identify and manage those not being treated according to guideline recommendations.

Major Bleeding Risk During Anticoagulation with Warfarin, Dabigatran, Apixaban, or Rivaroxaban in Patients with Nonvalvular Atrial Fibrillation

BACKGROUND The use of non-vitamin K oral anticoagulants (NOACs) has increased steadily following marketing approval; however, their relative safety in nonvalvular atrial fibrillation (NVAF) patients in real-world clinical practice remains unclear. OBJECTIVE To compare the risk of major bleeding during anticoagulation therapy between warfarin and NOACs. METHODS This retrospective cohort study analyzed administrative claims data on new NVAF users of warfarin, dabigatran, apixaban, or rivaroxaban in routine clinical care from November 2010 to February 2015 in a commercially insured population in the United States. The primary outcome was time to first major bleeding event requiring hospitalization. Patients were followed until discontinuation or switch of anticoagulants, health plan disenrollment, death, or end of study. All patient characteristics were balanced after propensity score inverse probability of treatment (IPT) weighting. Event rates by type of anticoagulant exposure were compared using IPT-weighted Cox proportional hazards models. RESULTS The study cohort comprised 44,057 patients who used warfarin (n = 23,431), dabigatran (n = 8,539), apixaban (n = 3,689), and rivaroxaban (n = 8,398). Overall mean (SD) age was 70 (12) years, and 41% of the patients were women. A total of 2,337 major bleeding events occurred during 36,636.2 person-years of follow-up. The unadjusted rate of major bleeding with warfarin was 6.0 per 100 person-years versus 2.8 with dabigatran, 3.3 with apixban, and 5.0 with rivaroxaban. Relative to warfarin, major bleeding risk was lower with dabigatran (HR = 0.67, 95% CI = 0.60-0.76) and apixaban (HR = 0.52, 95% CI = 0.41-0.67). Compared with rivaroxaban, major bleeding risk was also lower with dabigatran (HR = 0.67, 95% CI = 0.58-0.78) and apixaban (HR = 0.52, 95% CI = 0.40-0.68). Major bleeding risk was similar for rivaroxaban and warfarin. Relative to apixaban, dabigatran was associated with a significantly higher risk of major gastrointestinal bleeding (HR = 1.43, 95% CI = 1.09-1.88). CONCLUSIONS Study results were consistent with safety findings from pivotal clinical trials comparing NOACs with warfarin and added the perspective of a large real-world observational study that compared bleeding risks associated with NOACs during anticoagulation therapy. Apixaban and dabigatran were associated with lower major bleeding risk compared with warfarin or rivaroxaban; however, apixaban had a lower risk of major gastrointestinal bleeding than dabigatran. These findings can help inform the choice of an optimal agent, which must balance effectiveness and bleeding risk in complex patients. DISCLOSURES This study was funded by Anthem. Adeboyeje, Sylwestrzak, and Barron are employees of HealthCore, a wholly owned and independently operated subsidiary of Anthem. White, Rosenberg, Abarca, and Crawford are employees of Anthem. Study concept and design were primarily contributed by Adeboyeje and Sylwestrzak, along with the other authors. Adeboyeje took the lead in data collection, along with Sylwestrzak and Barron. Data interpretation was performed primarily by Rosenberg, Crawford, and Redberg, with assistance from the other authors. The manuscript was written by all the authors and revised primarily by White, Abarca, and Redberg, along with the other authors.

Improving the Use of Data Sources in Disease Management Programs

Disease management has become an increasingly popular tool used to manage people with chronic diseases in managed care organizations. The implementation of these programs, coupled with pressures to document quality and control costs, has increased the need for information regarding the health services provided to patients. This paper gives an overview of selected topics involved in data collection, including medical record review, databases, automated systems, and disease management software. The preliminary uses of the Internet and wireless technology are also discussed.Efficient data collection requires the identification of pertinent information from clinical, patient-reported, and economic data. Several sources provide this. The medical record is considered the gold standard for providing clinical information. However, collecting this data can be time consuming and expensive. Claims that databases have gained popularity for their comprehensiveness and accessibility are eroded by the lack of detailed clinical information. Direct communication with patients via telephone is commonly used in disease management programs, but its effectiveness as a data collection tool is not well documented. The use of the Internet and wireless technology in data collection is an exciting opportunity, since it provides interactive access between providers, patients, and the managed care organization.In most cases, a combination of data sources will be required to collect all the necessary information. However, claims databases, medical chart review, and telephone interviews are the backbone of data collection in disease management. The computerization of medical information systems, and use of the Internet and wireless technologies, should facilitate future data collection.

Impact of delayed initiation of erythropoietin in critically ill patients

BackgroundThe purpose of this study was to evaluate the impact of recombinant human erythropoietin (rHuEPO) use for anemia of critical illness at a practice site where delayed initiation is common.MethodsRetrospective medical record review involving patients treated with rHuEPO for anemia of critical illness. Those patients given rHuEPO or diagnosed with end-stage renal disease (ESRD) prior to ICU admission were excluded. The primary endpoints were rHuEPO use and RBC transfusion patterns.ResultsComplete data were collected for consecutive admissions of 126 patients. Average age (SD) and APACHE II score were 56.5 (18.6) years and 25 (7.8), respectively. The median ICU (IQR) and hospital length of stay (LOS) were 24 (11.25, 39) and 29 (17, 44.75) days, respectively. Treatment with rHuEPO was started an average of 12.5 +/- 10.5 days after ICU admission and given for 3.8 +/- 3.8 doses. Eighty percent of patients were transfused with an average total of 5.42 +/- 5.08 units received. RBC exposure inversely correlated with a lower mean hemoglobin response to rHuEPO. ICU LOS (p < 0.0001), hemoglobin at 24 hours (p = 0.055), transfusion within 48 hours of admit (p < 0.0001), and postoperative status (p = 0.019) were the best predictors of transfusion requirements (r2 = 0.37).ConclusionDelayed initiation of rHuEPO for anemia of critical illness resulted in comparable hemoglobin and transfusion benefits. Future studies are needed to establish clinical benefit and role in therapy. RBC exposure may blunt the erythropoietic effects of rHuEPO, potentially frustrating benefits to those of greatest apparent need.

PCV16 INCREMENTAL EFFECTS OF CONCURRENT PHARMACOTHERAPEUTIC REGIMENS FOR HEART FAILURE ON HOSPITALIZATIONS AND COSTS

BACKGROUND Inappropriate medication use in patients with heart failure (HF) presents challenges in providing optimal, evidence-based care. OBJECTIVE To evaluate the incremental differences of concurrent and persistent use of angiotensin-converting enzyme (ACE) inhibitors, beta-blockers, loop diuretics, and digoxin on the one-year, all-cause risk of hospitalization and total healthcare costs associated with treatment of HF in patients enrolled in a managed care organization within the US. METHODS A retrospective database analysis was conducted spanning from January 1, 1997, to December 31, 1999. Multivariate regression methods were used to examine the association between treatment regimens and hospitalizations or costs after controlling for patient demographics and risk factors. RESULTS Of the 1903 patients meeting inclusion criteria, 32.3% (n = 615) received none of the 4 HF agents studied and were associated with a 2.5 times greater risk (p < or = 0.001) of hospitalization and 43.6% higher (p < or = 0.001) total costs compared with all other patients with HF. Comparatively, 13.9% (n = 264) utilized the HF medications investigated for at least 6 months. Of those with persistent use of > or =3 agents, approximate decreases in hospitalizations were noted of 80% (p < or = 0.001) and total costs of 70% (p < or = 0.001) relative to patients receiving no HF therapy. CONCLUSIONS A substantial portion of patients with HF may be receiving suboptimal pharmacotherapeutic care in real-world practice settings, potentially incurring large increases in hospitalizations and total costs. Quality improvement initiatives should seek to identify and manage those not being treated according to guideline recommendations.