Ilene H. Zuckerman

The Use and Interpretation of Quasi-Experimental Studies in Infectious Diseases

Quasi-experimental study designs, sometimes called nonrandomized, pre-post-intervention study designs, are ubiquitous in the infectious diseases literature, particularly in the area of interventions aimed at decreasing the spread of antibiotic-resistant bacteria. Little has been written about the benefits and limitations of the quasi-experimental approach. This article outlines a hierarchy of quasi-experimental study design that is applicable to infectious diseases studies and that, if applied, may lead to sounder research and more-convincing causal links between infectious diseases interventions and outcomes.

Benchmark data from more than 240,000 adults that reflect the current practice of critical care in the United States.

BACKGROUND Nationwide benchmarks representing current critical care practice for the range of ICUs are lacking. This information may highlight opportunities for care improvement and allows comparison of ICU practice data. METHODS Data representing 243,553 adult admissions from 271 ICUs and 188 US nonfederal hospitals during 2008 were analyzed using the eICU Research Institute clinical practice database. Participating ICUs and hospitals varied widely regarding bed number, community size, academic status, geographic location, and organizational structure. RESULTS More than one-half of these critically ill adults were < 65 years old, and most patients returned to their homes after hospital discharge. Most patients were admitted from an ED, had a medical admission diagnosis, and received antimicrobial therapy. Intensive treatment was common, including 27% who received mechanical ventilation, 7.5% who were supported with noninvasive ventilation, 24.3% who were treated with vasoactive infusions, > 20% who received a blood product, and 4.4% who agreed to a care limitation order during their ICU stay. Forty percent of cases had a < 10% mortality risk and did not have an intensive treatment documented. CONCLUSIONS Admission to an ICU in 2008 involved active treatments that often included life support and counseling for those near the end of life and was associated with favorable outcomes for most patients.

Adherence Feedback to Improve Asthma Outcomes Among Inner-City Children: A Randomized Trial

OBJECTIVE: We evaluated the longitudinal effects of home-based asthma education combined with medication adherence feedback (adherence monitoring with feedback [AMF]) and asthma education alone (asthma basic care [ABC]) on asthma outcomes, relative to a usual-care (UC) control group. METHODS: A total of 250 inner-city children with asthma (mean age: 7 years; 62% male; 98% black) were recruited from a pediatric emergency department (ED). Health-outcome measures included caregiver-frequency of asthma symptoms, ED visits, hospitalizations, and courses of oral corticosteroids at baseline and 6-, 12-, and 18-month assessments. Adherence measures included caregiver-reported adherence to inhaled corticosteroid (ICS) therapy and pharmacy records of ICS refills. Multilevel modeling was used to examine the differential effects of AMF and ABC compared with UC. RESULTS: ED visits decreased more rapidly for the AMF group than for the UC group, but no difference was found between the ABC and UC groups. The AMF intervention led to short-term improvements in ICS adherence during the active-intervention phase relative to UC, but this improvement decreased over time. Asthma symptoms and courses of corticosteroids decreased more rapidly for the ABC group than for the UC group. Hospitalization rates did not differ between either intervention group and the UC group. No differences were found between the ABC and AMF groups on any outcome. CONCLUSIONS: Asthma education led to improved adherence and decreased morbidity compared with UC. Home-based educational interventions may lead to modest short-term improvements in asthma outcomes among inner-city children. Adherence feedback did not improve outcomes over education alone.

The association of psychotropic medication use with the cognitive, functional, and neuropsychiatric trajectory of Alzheimer's disease.

The use of psychotropic medications in Alzheimers disease (AD) has been associated with both deleterious and potentially beneficial outcomes. We examined the longitudinal association of psychotropic medication use with cognitive, functional, and neuropsychiatric symptom (NPS) trajectories among community‐ascertained incident AD cases from the Cache County Dementia Progression Study.

Association between intensive care unit-acquired dysglycemia and in-hospital mortality.

Objective:Our objective was to quantify the association between intensive care unit–acquired dysglycemia (hyperglycemia, hypoglycemia, and high variability) and in-hospital mortality. Design:Retrospective, observational study. Setting:eICU Research Institute participating hospitals with an active tele-ICU program between January 1, 2008, and September 30, 2010, representing 784,392 adult intensive care unit patients. Patients:A total of 194,772 patients met inclusion criteria with an intensive care unit length of stay >48 hrs. Interventions:None. Measurements and Main Results:Acute Physiology and Chronic Health Evaluation IV standardized mortality ratios were calculated for dysglycemia present at admission and acquired in the intensive care unit. Intensive care unit–acquired dysglycemia was modeled using multivariable modified Poisson regression to account for confounding not incorporated in Acute Physiology and Chronic Health Evaluation. Dysglycemia severity was assessed by the relative risk of in-hospital mortality associated with the maximum, time-weighted average daily glucose; lowest glucose value throughout the intensive care unit stay; and quintiles of variability (coefficient of variation). The association of duration beyond thresholds of dysglycemia on mortality was also modeled. The adjusted relative risk (95% confidence interval) of mortality for the maximum intensive care unit average daily glucose was 1.13 (1.04–1.58), 1.43 (1.30–1.58), 1.63 (1.47–1.81), 1.76 (1.55–1.99), and 1.89 (1.62–2.19) for 110–150 mg/dL, 151–180 mg/dL, 180–240 mg/dL, 240–300 mg/dL, and >300 mg/dL, respectively, compared to patients whose highest average daily glucose was 80–110 mg/dL. The relative risk of mortality for the lowest glucose value was 1.67 (1.37–2.03), 1.53 (1.37–1.70), 1.12 (1.04–1.21), and 1.06 (1.01–1.11) for <20 mg/dL, 20–40 mg/dL, 40–60 mg/dL, and 60–80 mg/dL, respectively, compared to patients whose lowest value was 80–110 mg/dL. The relative risk of mortality increased with greater duration of hyperglycemia and with increased variability. The relative risk for the highest compared to lowest quintile of variability was 1.61 (1.47–1.78). The association of duration of hyperglycemia on mortality was more pronounced with more severe hyperglycemia. Conclusions:The risk of mortality progressively increased with severity and duration of deviation from euglycemia and with increased variability. These data suggest that severe intensive care unit–acquired hyperglycemia, hypoglycemia, and variability are associated with similar risks of mortality.

Out-of-pocket health care expenditure burden for Medicare beneficiaries with cancer

BACKGROUND: There is increasing concern regarding the financial burden of care on cancer patients and their families. Medicare beneficiaries often have extensive comorbidities and limited financial resources, and may face substantial cost sharing even with supplemental coverage. In the current study, the authors examined out‐of‐pocket (OOP) spending and burden relative to income for Medicare beneficiaries with cancer.

Association of chronic obstructive pulmonary disease maintenance medication adherence with all-cause hospitalization and spending in a Medicare population.

BACKGROUND Although maintenance medications are a cornerstone of chronic obstructive pulmonary disease (COPD) management, adherence remains suboptimal. Poor medication adherence is implicated in poor outcomes with other chronic conditions; however, little is understood regarding links between adherence and outcomes in COPD patients. OBJECTIVE This study investigates the association of COPD maintenance medication adherence with hospitalization and health care spending. METHODS Using the 2006 to 2007 Chronic Condition Warehouse administrative data, this retrospective cross-sectional study included 33,816 Medicare beneficiaries diagnosed with COPD who received at least 2 prescriptions for ≥1 COPD maintenance medications. After a 6-month baseline period (January 1, 2006 to June 30, 2006), beneficiaries were followed through to December 31, 2007 or death. Two medication adherence measures were assessed: medication continuity and proportion of days covered (PDC). PDC values ranged from 0 to 1 and were calculated as the number of days with any COPD maintenance medication divided by duration of therapy with these agents. The association of adherence with all-cause hospital events and Medicare spending were estimated using negative binomial and γ generalized linear models, respectively, adjusting for sociodemographics, Social Security disability insurance status, low-income subsidy status, comorbidities, and proxy measures of disease severity. RESULTS Improved adherence using both measures was significantly associated with reduced rate of all-cause hospitalization and lower Medicare spending. Patients who continued with their medications had lower hospitalization rates (relative rate [RR] = 0.88) and lower Medicare spending (-

Treatment of Dementia in Community‐Dwelling and Institutionalized Medicare Beneficiaries

3764), compared with patients who discontinued medications. Similarly, patients with PDC ≥0.80 exhibited lower hospitalization rates (RR = 0.90) and decreased spending (-

Inappropriate drug use and risk of transition to nursing homes among community-dwelling older adults.

2185), compared with patients with PDC <0.80. CONCLUSIONS COPD patients with higher adherence to prescribed regimens experienced fewer hospitalizations and lower Medicare costs than those who exhibited lower adherence behaviors. Findings suggested the clinical and economic importance of medication adherence in the management of COPD patients in the Medicare population.

Trends in the prescription of inappropriate drugs for the elderly between 1995 and 1999

OBJECTIVES: To establish nationally representative estimates of the use of agents to treat Alzheimers disease and related dementias (ADRDs) and related behavioral symptoms in Medicare beneficiaries and to describe medication use according to residential status and other patient characteristics.