Megan E. Amuan

Prevalence of unplanned hospitalizations caused by adverse drug reactions in older veterans.

To describe the prevalence of unplanned hospitalizations caused by adverse drug reactions (ADRs) in older veterans and to examine the association between this outcome and polypharmacy after controlling for comorbidities and other patient characteristics.

Trends in antiepileptic drug prescribing for older patients with new-onset epilepsy: 2000-2004.

Background: Newer antiepileptic drugs (AEDs) have been shown to be equally efficacious as older seizure medications but with fewer neurotoxic and systemic side effects in the elderly. A growing body of clinical recommendations based on systematic literature review and expert opinion advocate the use of the newer agents and avoidance of phenobarbital and phenytoin. This study sought to determine if changes in practice occurred between 2000 and 2004—a time during which evidence and recommendations became increasingly available. Methods: National data from the Veterans Health Administration (VA; inpatient, outpatient, pharmacy) from 1998 to 2004 and Medicare data (1999–2004) were used to identify patients 66 years and older with new-onset epilepsy. Initial AED was the first AED received from the VA. AEDs were categorized into four groups: phenobarbital, phenytoin, standard (carbamazepine, valproate), and new (gabapentin, lamotrigine, levetiracetam, oxcarbazepine, topiramate). Results: We found a small reduction in use of phenytoin (70.6% to 66.1%) and phenobarbital (3.2% to 1.9%). Use of new AEDs increased significantly from 12.9% to 19.8%, due primarily to use of lamotrigine, levetiracetam, and topiramate. Conclusions: Despite a growing list of clinical recommendations and guidelines, phenytoin was the most commonly used antiepileptic drug, and there was little change in its use for elderly patients over 5 years. Research further exploring physician and health care system factors associated with change (or lack thereof) will provide better insight into the impact of clinical recommendations on practice. GLOSSARY: AED = antiepileptic drug; FDA = Food and Drug Administration; FY = fiscal year; RCT = randomized controlled trial; STVHCS = South Texas Veterans Health Care System; VA = Veterans Health Administration.

Potentially inappropriate prescribing in elderly veterans: Are we using the wrong drug, wrong dose, or wrong duration?

Objectives: To identify the extent of inappropriate prescribing using criteria for proper use developed by the Agency for Healthcare Research and Quality (AHRQ) and dose‐limitation criteria defined by Beers, as well as to describe duration of use and patient characteristics associated with inappropriate prescribing for older people.

New‐Onset Epilepsy Risk Factors in Older Veterans

OBJECTIVES: To identify risk factors for new‐onset geriatric epilepsy that may trigger clinicians to consider a differential diagnosis of epilepsy at symptom onset.

Suicide-related behaviors in older patients with new anti-epileptic drug use: data from the VA hospital system

BackgroundThe U.S. Food and Drug Administration (FDA) recently linked antiepileptic drug (AED) exposure to suicide-related behaviors based on meta-analysis of randomized clinical trials. We examined the relationship between suicide-related behaviors and different AEDs in older veterans receiving new AED monotherapy from the Veterans Health Administration (VA), controlling for potential confounders.MethodsVA and Medicare databases were used to identify veterans 66 years and older, who received a) care from the VA between 1999 and 2004, and b) an incident AED (monotherapy) prescription. Previously validated ICD-9-CM codes were used to identify suicidal ideation or behavior (suicide-related behaviors cases), epilepsy, and other conditions previously associated with suicide-related behaviors. Each case was matched to controls based on prior history of suicide-related behaviors, year of AED prescription, and epilepsy status.ResultsThe strongest predictor of suicide-related behaviors (N = 64; Controls N = 768) based on conditional logistic regression analysis was affective disorder (depression, anxiety, or post-traumatic stress disorder (PTSD); Odds Ratio 4.42, 95% CI 2.30 to 8.49) diagnosed before AED treatment. Increased suicide-related behaviors were not associated with individual AEDs, including the most commonly prescribed AED in the US - phenytoin.ConclusionOur extensive diagnostic and treatment data demonstrated that the strongest predictor of suicide-related behaviors for older patients newly treated with AED monotherapy was a previous diagnosis of affective disorder. Additional, research using a larger sample is needed to clearly determine the risk of suicide-related behaviors among less commonly used AEDs.

Complex comorbidity clusters in OEF/OIF veterans: the polytrauma clinical triad and beyond.

Background:A growing body of research on US Veterans from Afghanistan and Iraq [Operations Enduring and Iraqi Freedom, and Operation New Dawn (OEF/OIF)] has described the polytrauma clinical triad (PCT): traumatic brain injury (TBI), posttraumatic stress disorder (PTSD), and pain. Extant research has not explored comorbidity clusters in this population more broadly, particularly co-occurring chronic diseases. Objectives:The aim of the study was to identify comorbidity clusters among diagnoses of deployment-specific (TBI, PTSD, pain) and chronic (eg, hypertension, diabetes) conditions, and to examine the association of these clusters with health care utilization and adverse outcomes. Research Design:This was a retrospective cohort study. Subjects:The cohort comprised OEF/OIF Veterans who received care in the Veterans Health Administration in fiscal years (FY) 2008–2010. Measures:We identified comorbidity using validated ICD-9-CM code–based algorithms and FY08–09 data, followed by which we applied latent class analysis to identify the most statistically distinct and clinically meaningful patterns of comorbidity. We examined the association of these clusters with process measures/outcomes using logistic regression to correlate medication use, acute health care utilization, and adverse outcomes in FY10. Results:In this cohort (N=191,797), we found 6 comorbidity clusters. Cluster 1: PCT+Chronic Disease (5%); Cluster 2: PCT (9%); Cluster 3: Mental Health+Substance Abuse (24%); Cluster 4: Sleep, Amputation, Chronic Disease (4%); Cluster 5: Pain, Moderate PTSD (6%); and Cluster 6: Relatively Healthy (53%). Subsequent health care utilization patterns and adverse events were consistent with disease patterns. Conclusions:These comorbidity clusters extend beyond the PCT and may be used as a foundation to examine coordination/quality of care and outcomes for OEF/OIF Veterans with different patterns of comorbidity.

Potentially inappropriate prescribing for the elderly: Effects of geriatric care at the patient and health care system level

Background:Many studies have identified patient characteristics associated with potentially inappropriate prescribing in the elderly (PIPE), however, little attention has been directed toward how health care system factors such as geriatric care may affect this patient safety issue. Objective:This study examines the association between geriatric care and PIPE in a community dwelling elderly population. Research Design:Cross-sectional retrospective database study. Subjects:Veterans age ≥65 years who received health care in the VA system during Fiscal Years (FY99-00), and also received at medications from the Veterans Administration in FY00. Measures:PIPE was identified using the Zhan adaptation of the Beers criteria. Geriatric care penetration was calculated as the proportion of patients within a facility who received at least 1 geriatric outpatient clinic or inpatient visit. Analyses:Logistic regression models with generalized estimating equations were used to assess the relationship between geriatric care and PIPE after controlling for patient and health care system characteristics. Results:Patients receiving geriatric care were less likely to have PIPE exposure (odds ratio, 0.64; 95% confidence interval, 0.59–0.73). There was also a weak effect for geriatric care penetration, with a trend for patients in low geriatric care penetration facilities having higher risk for PIPE regardless of individual geriatric care exposure (odds ratio, 1.14; 95% confidence interval, 0.99–1.30). Conclusions:Although geriatric care is associated with a lower risk of PIPE, additional research is needed to determine if heterogeneity in the organization and delivery of geriatric care resulted in the weak effect of geriatric care penetration, or whether this is a result of low power.

A national cohort study of the association between the polytrauma clinical triad and suicide-related behavior among US veterans who served in Iraq and Afghanistan

OBJECTIVES We examined the association of posttraumatic stress disorder (PTSD), traumatic brain injury, and chronic pain-the polytrauma clinical triad (PCT)-independently and with other conditions, with suicide-related behavior (SRB) risk among Operation Enduring Freedom (OEF; Afghanistan) and Operation Iraqi Freedom (OIF) veterans. METHODS We used Department of Veterans Affairs (VA) administrative data to identify OEF and OIF veterans receiving VA care in fiscal years 2009-2011; we used International Classification of Diseases, Ninth Revision, Clinical Modification codes to characterize 211652 cohort members. Descriptive statistics were followed by multinomial logistic regression analyses predicting SRB. RESULTS Co-occurrence of PCT conditions was associated with significant increase in suicide ideation risk (odds ratio [OR] = 1.9; 95% confidence interval [CI]=1.5, 2.4) or attempt and ideation (OR=2.6; 95% CI=1.5, 4.6), but did not exceed increased risk with PTSD alone (ideation: OR=2.3; 95% CI=2.0, 2.6; attempt: OR=2.0; 95% CI=1.4, 2.9; ideation and attempt: OR=1.8; 95% CI=1.2, 2.8). Ideation risk was significantly elevated when PTSD was comorbid with depression (OR=4.2; 95% CI=3.6, 4.8) or substance abuse (OR=4.7; 95% CI = 3.9, 5.6). CONCLUSIONS Although PCT was a moderate SRB predictor, interactions among PCT conditions, particularly PTSD, and depression or substance abuse had larger risk increases.

The prevalence of epilepsy and association with traumatic brain injury in veterans of the Afghanistan and Iraq wars

Objective:To examine the association of epilepsy with traumatic brain injury (TBI) in Afghanistan and Iraq (Operation Enduring Freedom [OEF]/Operation Iraqi Freedom [OIF]) Veterans. Design:Cross-sectional observational study. Participants:A total 256 284 OEF/OIF Veterans who received inpatient and outpatient care in the Veterans Health Administration in fiscal years 2009-2010. Main Outcome Measures:We used algorithms developed for use with International Classification of Diseases, Ninth Revision, Clinical Modification, codes to identify epilepsy, TBI (penetrating TBI [pTBI]/other TBI), and other risk factors for epilepsy (eg, stroke). TBI and other risk factors were identified prior to the index date (first date of seizure or October 1, 2009) for primary analyses. Results:Epilepsy prevalence was 10.6 per 1000 (N = 2719) in fiscal year 2010; age-adjusted prevalence was 6.1. Of 37 718 individuals with a diagnosis of TBI, 29 297 Veterans had a diagnosis of TBI prior to the index date. Statistically significant associations were found between epilepsy and prior TBI diagnosis (pTBI: adjusted odds ratio = 18.77 [95% confidence interval, 9.21-38.23]; other TBI: adjusted odds ratio = 1.64 [1.43–1.89]). Conclusions:Among OEF/OIF Veterans, epilepsy was associated with previous TBI diagnosis, with pTBI having the strongest association. Because war-related epilepsy in Vietnam War Veterans with TBI continued 35 years postwar, a detailed, prospective study is needed to understand the relationship between epilepsy and TBI severity in OEF/OIF Veterans.

Influence of frailty-related diagnoses, high-risk prescribing in elderly adults, and primary care use on readmissions in fewer than 30 days for veterans aged 65 and older.

To determine the effect of two variables not previously studied in the readmissions literature (frailty‐related diagnoses and high‐risk medications in the elderly (HRME)) and one understudied variable (volume of primary care visits in the prior year).