Elliott Lowy

HIV Infection and the Risk of Acute Myocardial Infarction

IMPORTANCE Whether people infected with human immunodeficiency virus (HIV) are at an increased risk of acute myocardial infarction (AMI) compared with uninfected people is not clear. Without demographically and behaviorally similar uninfected comparators and without uniformly measured clinical data on risk factors and fatal and nonfatal AMI events, any potential association between HIV status and AMI may be confounded. OBJECTIVE To investigate whether HIV is associated with an increased risk of AMI after adjustment for all standard Framingham risk factors among a large cohort of HIV-positive and demographically and behaviorally similar (ie, similar prevalence of smoking, alcohol, and cocaine use) uninfected veterans in care. DESIGN AND SETTING Participants in the Veterans Aging Cohort Study Virtual Cohort from April 1, 2003, through December 31, 2009. PARTICIPANTS After eliminating those with baseline cardiovascular disease, we analyzed data on HIV status, age, sex, race/ethnicity, hypertension, diabetes mellitus, dyslipidemia, smoking, hepatitis C infection, body mass index, renal disease, anemia, substance use, CD4 cell count, HIV-1 RNA, antiretroviral therapy, and incidence of AMI. MAIN OUTCOME MEASURE Acute myocardial infarction. RESULTS We analyzed data on 82 459 participants. During a median follow-up of 5.9 years, there were 871 AMI events. Across 3 decades of age, the mean (95% CI) AMI events per 1000 person-years was consistently and significantly higher for HIV-positive compared with uninfected veterans: for those aged 40 to 49 years, 2.0 (1.6-2.4) vs 1.5 (1.3-1.7); for those aged 50 to 59 years, 3.9 (3.3-4.5) vs 2.2 (1.9-2.5); and for those aged 60 to 69 years, 5.0 (3.8-6.7) vs 3.3 (2.6-4.2) (P < .05 for all). After adjusting for Framingham risk factors, comorbidities, and substance use, HIV-positive veterans had an increased risk of incident AMI compared with uninfected veterans (hazard ratio, 1.48; 95% CI, 1.27-1.72). An excess risk remained among those achieving an HIV-1 RNA level less than 500 copies/mL compared with uninfected veterans in time-updated analyses (hazard ratio, 1.39; 95% CI, 1.17-1.66). CONCLUSIONS AND RELEVANCE Infection with HIV is associated with a 50% increased risk of AMI beyond that explained by recognized risk factors.

The association between nursing factors and patient mortality in the Veterans Health Administration: the view from the nursing unit level.

Context:Nurse staffing is not the same across an entire hospital. Nursing care is delivered in geographically-based units, with wide variation in staffing levels. In particular, staffing in intensive care is much richer than in nonintensive care acute units. Objective:To evaluate the association of in-hospital patient mortality with registered nurse staffing and skill mix comparing hospital and unit level analysis using data from the Veterans Health Administration (VHA). Design, Settings, and Patients:A retrospective observational study using administrative data from 129,579 patients from 453 nursing units (171 ICU and 282 non-ICU) in 123 VHA hospitals. Methods:We used hierarchical multilevel regression models to adjust for patient, unit, and hospital characteristics, stratifying by whether or not patients had an ICU stay during admission. Main Outcome Measure:In-hospital mortality. Results:Of the 129,579 patients, mortality was 2.9% overall: 6.7% for patients with an ICU stay compared with 1.6% for those without. Whether the analysis was done at the hospital or unit level affected findings. RN staffing was not significantly associated with in-hospital mortality for patients with an ICU stay (OR, 1.02; 95% CI, 0.99–1.03). For non-ICU patients, increased RN staffing was significantly associated with decreased mortality risk (OR, 0.91; 95% CI, 0.86–0.96). RN education was not significantly associated with mortality. Conclusions:Our findings suggest that the association between RN staffing and skill mix and in-hospital patient mortality depends on whether the analysis is conducted at the hospital or unit level. Variable staffing on non-ICU units may significantly contribute to in-hospital mortality risk.

Predicting risk of hospitalization or death among patients receiving primary care in the Veterans Health Administration.

Background:Statistical models that identify patients at elevated risk of death or hospitalization have focused on population subsets, such as those with a specific clinical condition or hospitalized patients. Most models have limitations for clinical use. Our objective was to develop models that identified high-risk primary care patients. Methods:Using the Primary Care Management Module in the Veterans Health Administration (VHA)’s Corporate Data Warehouse, we identified all patients who were enrolled and assigned to a VHA primary care provider on October 1, 2010. The outcome variable was the occurrence of hospitalization or death during the subsequent 90 days and 1 year. We extracted predictors from 6 categories: sociodemographics, medical conditions, vital signs, prior year use of health services, medications, and laboratory tests and then constructed multinomial logistic regression models to predict outcomes for over 4.6 million patients. Results:In the predicted 95th risk percentiles, observed 90-day event rates were 19.6%, 6.2%, and 22.6%, respectively, for hospitalization, death, and either hospitalization or death, compared with population averages of 2.7%, 0.7%, and 3.4%, respectively; 1-year event rates were 42.3%, 19.4%, and 51.3%, respectively, compared with population averages of 8.2%, 2.6%, and 10.8%, respectively. The C-statistics for 90-day outcomes were 0.83, 0.86, and 0.81, respectively, for hospitalization, death, and either hospitalization or death and were 0.81, 0.85, and 0.79, respectively, for 1-year outcomes. Conclusions:Prediction models using electronic clinical data accurately identified patients with elevated risk for hospitalization or death. This information can enhance the coordination of care for patients with complex clinical conditions.

Nurse staffing and patient outcomes in Veterans Affairs hospitals.

Objective: To assess characteristics and perceptions of nurses working in the Veterans Health Administration (VHA), comparing types of nursing personnel, to benchmark to prior studies across healthcare systems. Background: Prior studies have shown relationships between positive registered nurse (RN) perceptions of the practice environment and patient outcomes. To date, no study has reported the comparison of RN perceptions of the practice environment in hospital nursing with those of non-RN nursing personnel. This study is the first to offer a more comprehensive look at perceptions of practice environment from the full range of the nursing work force and may shed light on issues such as the relationship of skill mix to nurse and patient outcomes. Methods: Cross-sectional observational study with a mailed survey administered to all nursing personnel in 125 VA Medical Centers between February and June 2003. Results: Compared with other types of nursing personnel in the VHA, RNs are generally less positive about their practice environments. However, compared with RNs in other countries and particularly with other RNs in the United States (Pennsylvania), VHA RNs are generally more positive about their practice environment and express more job satisfaction. Conclusions: The nursing work force of the VHA has some unique characteristics. The practice environment for nurses in the VHA is relatively positive, and may indicate that the VHA, as a system, provides an environment that is more like magnet hospitals. This is significant for a public sector hospital system.

Declining mortality following acute myocardial infarction in the Department of Veterans Affairs Health Care System

BackgroundMortality from acute myocardial infarction (AMI) is declining worldwide. We sought to determine if mortality in the Veterans Health Administration (VHA) has also been declining.MethodsWe calculated 30-day mortality rates between 2004 and 2006 using data from the VHA External Peer Review Program (EPRP), which entails detailed abstraction of records of all patients with AMI. To compare trends within VHA with other systems of care, we estimated relative mortality rates between 2000 and 2005 for all males 65 years and older with a primary diagnosis of AMI using administrative data from the VHA Patient Treatment File and the Medicare Provider Analysis and Review (MedPAR) files.ResultsUsing EPRP data on 11,609 patients, we observed a statistically significant decline in adjusted 30-day mortality following AMI in VHA from 16.3% in 2004 to 13.9% in 2006, a relative decrease of 15% and a decrease in the odds of dying of 10% per year (p = .011). Similar declines were found for in-hospital and 90-day mortality.Based on administrative data on 27,494 VHA patients age 65 years and older and 789,400 Medicare patients, 30-day mortality following AMI declined from 16.0% during 2000-2001 to 15.7% during 2004-June 2005 in VHA and from 16.7% to 15.5% in private sector hospitals. After adjusting for patient characteristics and hospital effects, the overall relative odds of death were similar for VHA and Medicare (odds ratio 1.02, 95% C.I. 0.96-1.08).ConclusionMortality following AMI within VHA has declined significantly since 2003 at a rate that parallels that in Medicare-funded hospitals.

Predicting Risk of Hospitalization or Death Among Patients With Heart Failure in the Veterans Health Administration

Patients with heart failure (HF) are at high risk of hospitalization or death. The objective of this study was to develop prediction models to identify patients with HF at highest risk for hospitalization or death. Using clinical and administrative databases, we identified 198,460 patients who received care from the Veterans Health Administration and had ≥1 primary or secondary diagnosis of HF that occurred within 1 year before June 1, 2009. We then tracked their outcomes of hospitalization and death during the subsequent 30 days and 1 year. Predictor variables chosen from 6 clinically relevant categories of sociodemographics, medical conditions, vital signs, use of health services, laboratory tests, and medications were used in multinomial regression models to predict outcomes of hospitalization and death. In patients who were in the ≥95th predicted risk percentile, observed event rates of hospitalization or death within 30 days and 1 year were 27% and 80% respectively, compared to population averages of 5% and 31%, respectively. The c-statistics for the 30-day outcomes were 0.82, 0.80, and 0.80 for hospitalization, death, and hospitalization or death, respectively, and 0.82, 0.76, and 0.77, respectively, for 1-year outcomes. In conclusion, prediction models using electronic health records can accurately identify patients who are at highest risk for hospitalization or death. This information can be used to assist care managers in selecting patients for interventions to decrease their risk of hospitalization or death.

Preoperative consultations for medicare patients undergoing cataract surgery.

IMPORTANCE Low-risk elective surgical procedures are common, but there are no clear guidelines for when preoperative consultations are required. Such consultations may therefore represent a substantial discretionary service. OBJECTIVE To assess temporal trends, explanatory factors, and geographic variation for preoperative consultation in Medicare beneficiaries undergoing cataract surgery, a common low-risk elective procedure. DESIGN, SETTING, AND PARTICIPANTS Cohort study using a 5% national random sample of Medicare part B claims data including a cohort of 556,637 patients 66 years or older who underwent cataract surgery from 1995 to 2006. Temporal trends in consultations were evaluated within this entire cohort, whereas explanatory factors and geographic variation were evaluated within the 89,817 individuals who underwent surgery from 2005 to 2006. MAIN OUTCOMES AND MEASURES Separately billed preoperative consultations (performed by family practitioners, general internists, pulmonologists, endocrinologists, cardiologists, nurse practitioners, or anesthesiologists) within 42 days before index surgery. RESULTS The frequency of preoperative consultations increased from 11.3% in 1998 to 18.4% in 2006. Among individuals who underwent surgery in 2005 to 2006, hierarchical logistic regression modeling found several factors to be associated with preoperative consultation, including increased age (75-84 years vs 66-74 years: adjusted odds ratio [AOR], 1.09 [95% CI, 1.04-1.13]), race (African American race vs other: AOR, 0.71 [95% CI, 0.65-0.78]), urban residence (urban residence vs isolated rural town: AOR, 1.64 [95% CI, 1.49-1.81]), facility type (outpatient hospital vs ambulatory surgical facility: AOR, 1.10 [95% CI, 1.05-1.15]), anesthesia provider (anesthesiologist vs non-medically directed nurse anesthetist: AOR, 1.16 [95% CI, 1.10-1.24), and geographic region (Northeast vs South: AOR, 3.09 [95% CI, 2.33-4.10]). The burden of comorbidity was associated with consultation, but the effect size was small (<10%). Variation in frequency of consultation across hospital referral regions was substantial (median [range], 12% [0-69%]), even after accounting for differences in patient-level, anesthesia provider-level, and facility-level characteristics. CONCLUSIONS AND RELEVANCE Between 1995 and 2006, the frequency of preoperative consultation for cataract surgery increased substantially. Referrals for consultation seem to be primarily driven by nonmedical factors, with substantial geographic variation.

Association Between Hyperglycemia at Admission During Hospitalization for Acute Myocardial Infarction and Subsequent Diabetes: Insights From the Veterans Administration Cardiac Care Follow-up Clinical Study

OBJECTIVE Among patients with acute myocardial infarction (AMI) without known diabetes, hyperglycemia at admission is common and associated with worse outcomes. It may represent developing diabetes, but this association is unclear. Therefore, we examined the association between hyperglycemia (≥140 mg/dL) at admission and evidence of diabetes among patients with AMI without known diabetes within 6 months of their hospitalization. RESEARCH DESIGN AND METHODS We studied a national cohort of consecutive patients with AMI without known diabetes presenting at 127 Veterans Affairs hospitals between October 2005 and March 2011. Evidence of diabetes either at discharge or in the following 6 months was ascertained using diagnostic codes, medication prescriptions, and/or elevated hemoglobin A1c. Association between hyperglycemia at admission and evidence of diabetes was evaluated using regression modeling. RESULTS Among 10,499 patients with AMI without known diabetes, 98% were men and 1,761 (16.8%) had hyperglycemia at admission. Within 6 months following their index hospitalization, 208 patients (11.8%) with hyperglycemia at admission had evidence of diabetes compared with 443 patients (5.1%) without hyperglycemia at admission (P < 0.001). After multivariable adjustment, hyperglycemia at admission was significantly associated with subsequent diabetes odds ratio 2.56 (95% CI 2.15–3.06). Among those with new evidence of diabetes, 41% patients (267 of 651) had a hemoglobin A1c ≥6.5% without accompanying diagnostic codes or medication prescriptions, suggesting they had unrecognized diabetes. CONCLUSIONS Hyperglycemia at admission occurred in one of six patients with AMI without known diabetes and was significantly associated with new evidence of diabetes in the 6 months following hospitalization. In addition, two of five patients with evidence of diabetes were potentially unrecognized. Accordingly, diabetes-screening programs for hyperglycemic patients with AMI may be an important component of optimal care.

Organizational factors associated with decreased mortality among veterans affairs patients with an ICU Stay

In-hospital mortality rates associated with an ICU stay are high and vary widely among units. This variation may be related to organizational factors such as staffing patterns, ICU structure, and care processes. We aimed to identify organizational factors associated with variation in in-hospital mortality for patients with an ICU stay. This was a retrospective observational cross-sectional study using administrative data from 34 093 patients from 171 ICUs in 119 Veterans Health Administration hospitals. Staffing and patient data came from Veterans Health Administration national databases. ICU characteristics came from a survey in 2004 of ICUs within the Veterans Health Administration. We conducted multilevel multivariable estimation with patient-, unit-, and hospital-level data. The primary outcome was in-hospital mortality. Of 34 093 patients, 2141 (6.3%)died in the hospital. At the patient level, risk of complications and having a medical diagnosis were significantly associated with a higher risk of mortality. At the unit level, having an interface with the electronic medical record was significantly associated with a lower risk of mortality. The finding that electronic medical records integrated with ICU information systems are associated with lower in-hospital mortality adds support to existing evidence on organizational characteristics associated with in-hospital mortality among ICU patients.

Factors associated with presenting >12 hours after symptom onset of acute myocardial infarction among Veteran men

BackgroundApproximately 2/3 of Veterans admitting to Veterans Health Administration (VHA) facilities present >12 hours after symptom onset of acute myocardial infarction (AMI) (“late presenters”). Veterans admitted to VHA facilities with AMI may delay hospital presentation for different reasons compared to their general population counter parts. Despite the large descriptive literature on factors associated with delayed presentation in the general population, the literature describing these factors among the Veteran AMI population is limited. The purpose of this analysis is to identify predictors of late presentation in the Veteran population presenting with AMI to VHA facilities. Identifying predictors will help inform and target interventions for Veterans at a high risk of late presentation.MethodsIn our cross-sectional study, we analyzed a cohort of 335 male Veterans from nine VHA facilities with physician diagnosed AMI between April 2005 and December 2006. We compared demographics, presentation characteristics, medical history, perceptions of health, and access to health care between early and late presenting Veterans. We used standard descriptive statistics for bivariate comparisons and multivariate logistic regression to identify independent predictors of late presentation.ResultsOur cohort was an average of 64 ± 10 years old and was 88% white. Sixty-eight percent of our cohort were late presenters. Bivariate comparisons found that fewer late presenters had attended at least some college or vocational school (late 53% vs. early 66%, p = 0.02). Multivariate analysis showed that presentation with ST-elevation myocardial infarction (STEMI) was associated with early presentation (OR = 0.4 95%CI [0.2, 0.9]) and ≥2 angina episodes in the prior 24 hours (versus 0-1 episode) was associated with late presentation (OR = 7.5 95%CI [3.6,15.6]).ConclusionsA significant majority of Veterans presenting to VHA facilities with AMI were late presenters. We found few differences between early and late presenters. Having a STEMI was independently associated with early presentation and reporting ≥2 angina episodes in the 24 hours prior to hospital admission was independently associated with late presentation. These independent predictors of early and late presentation are similar to what has been reported for the general population. Despite these similarities to the general population, there may be untapped opportunities for patient education within the VHA to decrease late presentation.