Research Briefs

Research Activities, June 2010, No. 358

Argo, J. L., Vick, C. C., Graham, L. A., and others (2009). "Elective surgical case cancellation in the Veterans Health Administration system: Identifying areas for improvement." (AHRQ grant HS13852). The American Journal of Surgery 198, pp. 600-608.

Unanticipated cancellations of elective surgeries decrease operating room efficiency and are inconvenient to patients, physicians, and staff. The researchers surveyed 40 Veterans Administration (VA) hospitals with the highest and lowest cancellation rates. There were 329,784 cases scheduled by 9 surgical specialties, of which 40,998 were cancelled. With a cancellation rate of 12.4 percent, the VA system lost more than $32 million in 2006. The reasons for cancellation were placed in five categories. The greatest proportion of cancellations were due to patient factors (35 percent), work-up/medical status change (28 percent), and facility factors (20 percent). The researchers caution against setting benchmarks for cancellation rates since case mix and patient population must be considered before planning a quality improvement program.

Castaldi, P. J., Cho, M. H., Cohn, M., and others (2010). "The COPD genetic association compendium: A comprehensive online database of COPD genetic associations." (AHRQ grant HS16808). Human Molecular Genetics 19(3), pp. 526-534.

Although smoking is the primary risk factor for the development of chronic obstructive pulmonary disease (COPD), family studies support the hypothesis that genetic variation contributes to COPD susceptibility. Only one gene has been definitively proven to influence COPD susceptibility. There have been promising findings from over 100 published COPD candidate gene studies but most have not been consistently replicated. The authors performed a systematic review and meta-analysis of 108 population-based, case-control articles pertaining to COPD genetic associations. A total of 72 genes were studied in the publication database. The authors identified 27 genetic variants that were suitable for quantitative meta-analysis. Four of these variants—GSTMI null, rs 1800470 in TGFBI, rs1800629 in TNF, and rs1799895 in SOD3—were significantly associated with COPD susceptibility. The authors recommend that these variants be targeted for future study.

Curtis, J. R., Arora, T., Xi, J., and others (2009). "Do physicians within the same practice setting manage osteoporosis patients similarly? Implications for implementation research." (AHRQ grant HS16956). Osteoporosis International 20, pp. 1921-1927.

To carry out implementation research studies, it is important to know whether randomizing groups of physicians who practice together in a common setting, rather than randomizing individual physicians, is necessary. Randomizing groups of physicians would avoid contamination between intervention and control physicians but at the cost of sacrificing statistical power and raising other design issues. The researchers examined data from two studies of osteoporosis management in long-term glucocorticoid users and nursing home patients with known osteoporosis or prior fracture. They found that physicians practicing together were not more alike in prescribing osteoporosis medications than those in different practices. The researchers concluded that osteoporosis quality management may be able to ignore common practice settings and maximize statistical power by targeting individual physicians.

Ghaferi, A. A., Birkmeyer, J. D., and Dimick, J. B. (2009, December). "Complications, failure to rescue, and mortality with major inpatient surgery in Medicare patients." (AHRQ grant HS17765). Annals of Surgery 250(6), pp. 1029-1034.

Some hospitals have higher surgical mortality rates than others. Many believe that high-mortality hospitals simply have higher complication rates. However, there is a growing body of evidence suggesting that complications and mortality are not related, i.e., hospitals with high rates of complications do not necessarily have high mortality rates. A possible explanation is that high-mortality hospitals may not be as proficient in recognizing and managing serious complications once they occur, a phenomenon known as failure to rescue. In a study of 269,911 patients who underwent 1 of 6 high-risk operations, the risk-adjusted mortality rate varied 2.5-fold between the worst-performing 20 percent and the top-performing 20 percent of hospitals. However, complication rates between these groups of hospitals were very similar (36.4 percent vs. 32.7 percent). In contrast, rates of failure to rescue were much higher at the worst-performing compared with the best-performing hospitals, with a nearly threefold difference (16.7 percent vs. 6.8 percent).

Hyzy, R. C., Flanders, S. A., Pronovost, P. J., and others (2010, January). "Characteristics of intensive care units in Michigan: Not an open and closed case." (AHRQ grant HS14246). Journal of Hospital Medicine 5(1), pp. 4-9.

Organization of physician services in intensive care units (ICUs) varies widely and influences mortality, morbidity, and costs of care. In order to understand the delivery of critical care physician services in Michigan, the researchers used a descriptive questionnaire to survey Michigan hospitals. They received 96 responses representing 72 hospitals with 115 ICUs. Twenty-four of 96 ICU sites were "closed," i.e., only intensivists served as the attending physician of record. Hospitals with closed ICUs were larger and had larger ICUs than sites with open ICUs or with nonintensivist decisionmaking. The presence of hospitalists serving as attending physicians was strongly associated with an open ICU, i.e., an ICU that had multiple attending specialists. Only 18 sites had 100 percent of their ICU attending physicians board-certified in critical care, with nearly two-thirds of sites having fewer than 50 percent of similarly certified attending physicians.

Memtsoudis, S. G., Ma, Y., Della Valle, A. G., and others (2009). "Perioperative outcomes after unilateral and bilateral total knee arthroplasty." (AHRQ grant HS16075). Anesthesiology 111, pp. 1206-1216.

Total knee arthroplasty (TKA) is the most effective treatment of end-stage osteoarthritis. When both knees are affected, bilateral TKA (BTKA) reduces the overall cost of care by 18-36 percent and duration of hospital stay by 4-6 days. However, the safety of BTKA remains controversial with studies reporting an associated increase in morbidity and mortality. To explore this issue, the researchers used 1998-2006 data from the Nationwide Inpatient Sample sponsored by the Agency for Healthcare Research and Quality. The researchers found an increased incidence of perioperative complications (9.45 percent vs. 7.07 percent) and in-hospital mortality (0.30 percent vs. 0.14 percent) among patients undergoing BTKA when compared with single TKA. BTKAs performed in a staged approach during the same hospitalization were associated with an increased incidence of in-hospital complications when compared with simultaneous BTKAs, and offered no mortality benefit.

Moore, C., Li, J., Hung, C., and others (2009, December). "Predictive value of alert triggers for identification of developing adverse drug events." (AHRQ Contract No. 290-00-0018). Journal of Patient Safety 5(4), pp. 223-228.

Clinical event monitors alert physicians to the possibility of an adverse drug event (ADE) and have generally been used to detect ADEs for tracking purposes or to ameliorate ongoing harm due to an ADE after a drug has been administered. ADEs were defined as the development of a drug-related critical laboratory value occurring between 1 and 72 hours after the initial trigger firing. Patients at a large teaching hospital were monitored using electronic triggers designed to detect patients at increased risk of four types of ADEs: hypoglycemia, hypokalemia, hyperkalemia, and thrombocytopenia. Overall, during the 5-month study period, the triggers fired 611 times on 456 patients, 101 of whom went on to experience one or more related ADEs within 72 hours after the initial trigger firing. The researchers concluded that these primary-prevention triggers have sufficient positive predictive value to effectively identify patients at high risk for experiencing ADEs in the future.

Pizer, S. D., Frakt, A. B., and Iezzoni, L. I. (2009, October). "Uninsured adults with chronic conditions or disabilities: Gaps in public insurance programs." (AHRQ grant HS15941). Health Affairs 28(6):w1141-w1150. Epub.

The researchers sought to determine the size of the uninsurance problem among working-age people with low incomes and chronic health conditions or disabilities. The data used came from the Bureau of Labor Statistics and the Agency for Healthcare Research and Quality's Medical Expenditure Panel Survey for the years 2000-2005. The rates of uninsured people increased overall from 13.7 percent in 2000 to 16 percent in 2005 (a 17 percent increase). However, there was only a 3.5 percent increase for low-income people with disabilities or health conditions who were in a Federal eligibility category. Those not in a Federal category saw rates jump 18.6 percent. The two large and growing gaps in public insurance programs were regional and categorical. The South had very high uninsurance rates compared with the much lower rates in the Northeast. Those not in federally mandated Medicaid eligibility categories had uninsurance rates that doubled compared with those in Federal categories.

Rivard, P. E., Elixhauser, A., Christiansen, C. L., and others (2009). "Testing the association between patient safety indicators and hospital structural characteristics in VA and nonfederal hospitals." Medical Care Research and Review Oct 30, 2009, Epub ahead of printing. Reprints (AHRQ Publication No. 10-R027) are available from the AHRQ Publications Clearinghouse.

The researchers studied the relationship between hospital characteristics (teaching status, number of staffed beds, nurse staffing levels, and urban/rural location) and 14 Agency for Healthcare Research and Quality Patient Safety Indicators (PSIs). Also included was a composite incorporating multiple PSIs. PSIs are software tools applied to administrative data to identify potentially preventable adverse events. Using discharge data from Veterans Administration (VA) and non-Federal hospitals, the researchers found that PSIs were more frequently associated with teaching status than with other hospital structural characteristics. In the non-Federal hospitals, PSIs were more likely in major teaching hospitals for four medical/surgical and two postoperative PSIs. The researchers believe that this relationship merits further study.

Ryan, A. M., Burgess, J. F., Tompkins, C. P., and Wallack, S. S. (2009, Fall). "The relationship between Medicare's process of care quality measures and mortality." (AHRQ grant T32 HS00062). Inquiry 446, pp. 274-290.

The massive costs of Medicare combined with concerns about the value of medical care received by Medicare beneficiaries led Congress to call for hospital value-based purchasing (VBP), a combination of pay-for-performance, and public quality reporting. A critical question is how health care quality will be assessed in VBP. One way to do this, utilized by these researchers, is to examine the relationship between process and mortality in the context of Hospital Compare, a voluntary, Internet-based public quality reporting program for hospital care. They found that performance on the starter set of Hospital Compare process measures is inversely correlated with risk-adjusted 30-day mortality for heart attack, heart failure, and pneumonia. However, differences in process performance were not associated with within-hospital variation in mortality. This suggests that process performance is not causally related to the mortality outcomes, and instead is a proxy for unobserved factors such as physician skill.

Singer, S. J., Falwell, A., Gaba, D. M., and others (2009, October-December). "Identifying organizational cultures that promote patient safety." (AHRQ grant HS13920). Health Care Management Review 34(4), pp. 300-311.

Startling statistics about the extent of preventable medical errors have directed attention to the "culture of safety" in health care organizations. The researchers examined the relationship between an organization's "safety climate" and its "culture of safety." "Climate" refers to shared perceptions related to a given, specific area of interest such as safety and "culture" refers to employees' fundamental ideology that explains why an objective like safety is pursued in a particular way. In their survey of 92 U.S. hospitals and 35,340 senior managers, physicians, and hospital staff, the researchers found that a higher level of group culture correlated with a higher level of safety climate, but a more hierarchical culture was associated with a lower safety climate. A mix of culture types, which emphasized group culture, seemed optimal for safety climate.

Vasilevskis, E. E., Knebel, R. J., Wachter, R. M., and Auerbach, A. D. (2009, November/December). "California hospital leaders' views of hospitalists: Meeting needs of the present and future." (AHRQ grant HS11416). Journal of Hospital Medicine 4(9), pp. 528-534.

Today there are more than 25,000 practicing hospitalists in the United States, with no signs of slackening demand. The researchers surveyed California hospital leaders to understand the prevalence of hospitalist groups in California hospitals as well as the scope of clinical and nonclinical practice of hospitalists. They received 179 responses from 332 California hospitals. Sixty-four percent of hospital leaders stated that they used hospitalists for at least some patients. The most important reasons for implementing a hospitalist model included caring for uncovered patients (68 percent), decreasing hospital costs and length of stay (63 percent), and improving throughput in the emergency room (62 percent). In addition to general medical care, the most common clinical activity of hospitalists was screening medical admissions from the emergency room (67 percent). The most common nonclinical activity was participation in quality improvement activities (72 percent).

Yoon, J., and Ettner, S. L. (2009). "Cost-sharing and adherence to antihypertensives for low and high adherers." (AHRQ grant HS16815). The American Journal of Managed Care 15(11), pp. 833-840.

Among factors influencing patients' adherence to drugs, one of the strongest relationships exists between higher out-of-pocket payments for drugs and less drug utilization, including lower adherence to drug prescriptions. The researchers examined the impact of cost-sharing on adherence to antihypertensive drugs across adherence levels. They performed a cross-sectional study of a large sample of working-age adults. Using the medication possession ratio (MPR) to measure drug adherence to antihypertensives over a 9-month period, they found that the regression-adjusted MPR was 8 to 9 points lower among patients with the highest cost-sharing compared with patients with the lowest cost-sharing (a co-payment of $5 or less). By contrast, there was no significant relationship between cost-sharing and adherence for high adherers. Other predictors of worse adherence were drug class and the presence of other illnesses.

Current as of June 2010
Internet Citation: Research Briefs: Research Activities, June 2010, No. 358. June 2010. Agency for Healthcare Research and Quality, Rockville, MD. http://archive.ahrq.gov/news/newsletters/research-activities/jun10/0610RA30.html