Virtual glucose monitoring, statins and heart surgery

Summaries from ACP Hospitalist Weekly.

Virtual glucose monitoring service may improve inpatient glycemic control

A virtual glucose management service decreased the number of inpatients who developed hyperglycemia or hypoglycemia in a recent study.

The virtual service entailed the electronic health record (EHR) generating daily reports that identified all adult inpatients with abnormal glucose values or insulin pump use. Then, before early morning rounds, one of three experienced diabetes clinicians reviewed each patient's chart and, if necessary, remotely entered a glucose management note with insulin recommendations.

To evaluate the effects of the service, researchers analyzed three 12-month periods between June 1, 2012, and May 31, 2015, (pre-intervention, transition, and intervention) at three University of California, San Francisco hospitals. They included 12,535 nonobstetric adult inpatients who underwent point-of-care glucose testing in the study. Results of the observational study were published online on March 28 by Annals of Internal Medicine and appear in the May 2 issue.

Primary outcomes were the proportion of patient-days classified as hyperglycemic (two or more glucose values ≥12.5 mmol/L [225 mg/dL]), at-goal (all glucose values between 3.9 and 10 mmol/L [70 and 180 mg/dL]), or hypoglycemic (a single glucose value <3.9 mmol/L [70 mg/dL] or <2.2 mmol/L [40 mg/dL] for severe hypoglycemia) per 100 hospitalized patients on a given calendar day.

From the pre-intervention period to the intervention period, the proportion of hyperglycemic patients per day decreased by 39%, from 6.6 per 100 patients to 4.0 per 100 patients (P<0.001). Meanwhile, the proportion of at-goal patient-days increased by 5%, from 10.8 per 100 patients in the pre-intervention period to 11.4 per 100 patients during the intervention period (P<0.001). During the same period, the proportion of hypoglycemic patients per day decreased by 36%, from 0.78 per 100 patients to 0.49 per 100 patients (P<0.001). In addition, the proportion with severe hypoglycemia decreased by 69%, from 0.032 per 100 patients to 0.010 per 100 patients (P<0.001).

One limitation of the study is that researchers did not collect information on patients' concurrent illnesses and treatments that might influence outcomes or information on physicians' orders, the authors noted.

An accompanying editorial called the improvements in glycemic control “impressive” but expressed concerns about adoption in inpatient settings outside the U.S. where there has been slower uptake of EHRs and electronic prescribing.

Another downside of the service is the absence of patient and subspecialist interaction, according to the editorial. “It is important to note that the 3 providers who gave advice had 10 to 30 years of inpatient diabetes experience among them,” the editorialist wrote. “Even greater improvements may have been possible if this level of experience were available at bedside.”

Statins on day of heart surgery may improve survival, outcomes

Statin use within 24 hours of surgery and a preoperative statin dose of more than 20 mg were independently associated with decreased 30-day all-cause mortality after coronary artery bypass graft (CABG) surgery, according to a study.

Researchers examined data from 3,025 patients who underwent CABG between July 2005 and May 2011 to determine the optimal dose and timing of preoperative statin administration. For patients who were admitted to the hospital on the day of the operation, the researchers reviewed preoperative medication questionnaires to determine the timing and dosage of the statin. For inpatients, nursing administration records were reviewed.

Patients were divided into three groups, according to timing of their preoperative statin: 24 hours or less (n=1,788), 24 to 72 hours (n=452), or more than 72 hours before operation or no dose (n=781). Patients were also divided by preoperative dose: no statin (n=739), 20 mg or less (n=920), or more than 20 mg (n=1,284) atorvastatin or equivalent.

The primary outcome was 30-day all-cause postoperative mortality. Results were published in the Annals of Thoracic Surgery on March 16.

The researchers found that for the 59% of patients (1,788) who had taken statins 24 hours or less before their operation, the incidence of 30-day all-cause mortality was 1.7%. That compares to 2.9% for those who took statins 24 to 72 hours before surgery and 3.8% for those who did not take statins or whose last dose was more than 72 hours before surgery. Multivariate analysis of a propensity-matched cohort showed that taking statins 24 hours or less before surgery was associated with reduced 30-day all-cause mortality (odds ratio, 0.52; 95% CI, 0.28 to 0.98; P=0.04) compared to taking them more than 24 hours before or not at all.

Separately, the researchers also looked at statin dose and surgery outcomes. They reviewed the records of 2,943 patients who underwent elective CABG and who had complete statin dosage documentation. They found that 30-day all-cause mortality was significantly lower in patients taking 20 mg or less (1.8%) or more than 20 mg of atorvastatin or equivalent (2.1%) than in those who took none (3.8%). In a multivariate analysis, a preoperative dose larger than 20 mg was associated with a 68% reduction of 30-day all-cause mortality (odds ratio, 0.32; 95% CI, 0.13 to 0.82; P=0.02) compared with no preoperative statin. However, a 20-mg or less preoperative dose showed no mortality reduction.

“Increasing evidence indicates that preoperative statin therapy may reduce perioperative morbidity and mortality in patients undergoing CABG surgery,” the authors wrote. “Our findings suggest that preoperative statin therapy is associated with a significant reduction of perioperative mortality after CABG operation.”

Medicare charges vary more by hospital clinician than by hospital, with no impact on mortality

Hospital clinicians (hospitalists and general internists) varied significantly in the cost of their care for Medicare patients, and there was no association between Part B spending and 30-day mortality or readmission rates, a recent study found.

The retrospective data analysis included 485,016 hospitalizations of Medicare fee-for-service beneficiaries. All patients were ages 65 years or older and were admitted due to a nonelective medical condition between 2011 and 2014. They were treated by 21,963 hospitalists at 2,837 hospitals. A secondary analysis of general internists included 839,512 hospitalizations and 50,079 physicians at 3,195 acute care hospitals. Results were published by JAMA Internal Medicine on March 13 and appear in the May issue.

The variation in Medicare Part B spending for patients was larger across physicians than across hospitals (for hospitalists, 8.4% vs. 7.0%; for general internists, 10.5% vs. 6.2%). Higher physician spending was not associated with any reduction in 30-day mortality or readmission rates in the analyses of both hospitalists and general internists. “Taken together, these findings suggest that not only does physician spending vary substantially even within the same hospital, but also that higher-spending physicians do not reliably achieve better patient outcomes,” the authors wrote.

Based on the results, they suggested that higher-spending physicians might be able to reduce their resource use without hurting patient care and that policy interventions targeting this goal on the inpatient physician level should be developed and evaluated. The authors noted that the study was limited by its use of only Part B spending data, but the differences in physician spending on this measure would likely translate to differences in use of resources covered under Part A, too.

An accompanying editorial comment said a strength of the study was its split sample approach, in which 2011 and 2012 spending data were compared to 2013 and 2014 outcomes, mitigating the risk of bias if a physician treated a particularly complex set of patients one year. The study's findings align with previous research showing significant geographic variation in Medicare spending, the commenter also noted.

Good door-to-balloon time not associated with fast stroke response, study finds

There was no correlation between door-to-balloon time for ST-segment elevation myocardial infarction (STEMI) and door-to-needle time for acute ischemic stroke among hospitals participating in the Get With The Guidelines (GWTG) programs, a recent study found.

The prospective study included all 43 hospitals that were participating in both GWTG-Stroke and GWTG-Coronary Artery Disease and treated at least 10 patients with the conditions in 2006 to 2009. Treatment times were analyzed for 1,976 patients with acute ischemic stroke and 59,823 patients with ST-segment–elevation myocardial infarction. Results were published in Circulation: Cardiovascular Quality and Outcomes on March 10.

The study found no correlation between the hospitals' door-to-needle and door-to-balloon times or between the proportions of eligible patients treated within the target time windows for the two conditions. The lack of correlation persisted after risk adjustment and when the same comparisons were made using data from 2013 to 2014, leading the study authors to conclude that no correlation existed in either observed or risk-adjusted times to treatment.

The findings align with previous research finding that although a hospital's high performance on one measure of cardiovascular care may be associated with higher-quality care for other cardiovascular conditions, the effect does not extend to conditions outside the subspecialty, the study authors said. The lack of correlation might be due to differences in emergency evaluation and care processes and/or different degrees of investment in improvement efforts for the two conditions. The authors noted that overall the hospitals were significantly better at meeting door-to-balloon time goals than those for door-to-needle time and that performance ranged more widely among hospitals on the latter measure.

The results could potentially be improved by more interdisciplinary cooperation and coordinated approaches, for example, assessing whether ED processes used for STEMI could be adapted for stroke response, the authors suggested. “Rather than singularly focusing on process improvement for individual conditions, there may be value in efforts to improve timely care for multiple acute disease states with more coordinated efforts,” they wrote.

Dysphagia screening underused, predicts stroke outcomes, study finds

Despite the potential benefits to predicting post-stroke outcomes, one in five patients with acute ischemic stroke did not receive dysphagia screening, and patients with mild strokes were substantially less likely to undergo screening, a study found.

To evaluate predictors of receiving dysphagia screening after acute ischemic stroke and outcomes after failing a screening test, researchers identified patients hospitalized with acute ischemic stroke via the Ontario Stroke Registry from April 1, 2010, to March 31, 2013, to determine predictors of screening and outcomes after failing the screening test, including pneumonia, disability, and death.

Results were published online on March 8 by Stroke.

Among 7,171 patients, 6,677 patients were eligible to receive dysphagia screening within 72 hours, yet 1,280 (19.2%) patients did not. Patients with mild strokes were significantly less likely than those with more severe strokes to have documented screening (adjusted odds ratio [OR], 0.51; 95% CI, 0.41 to 0.64). Failing dysphagia screening was associated with pneumonia (adjusted OR, 4.71; 95% CI, 3.43 to 6.47), severe disability (adjusted OR, 5.19; 95% CI, 4.48 to 6.02), discharge to long-term care (adjusted OR, 2.79; 95% CI, 2.11 to 3.79), and one-year mortality (adjusted hazard ratio, 2.42; 95% CI, 2.09 to 2.80).

Patients with a failed screening were also more likely to develop aspiration pneumonia (8.8% vs. 1.0%; adjusted OR, 6.5; 95% CI, 4.2 to 9.9) and decubitus ulcers (1.9% vs. 0.1%; adjusted OR, 12.7; 95% CI, 3.8 to 42.2) and were more likely to need a percutaneous feeding tube (9.0% vs. 0.1%; adjusted OR, 56.8; 95% CI, 20.9 to 154.4). Among patients with mild strokes, failing dysphagia screening also predicted pneumonia (8.2% vs. 1.3%; adjusted OR, 4.94; 95% CI, 3.14 to 7.89), severe disability (43.2% vs. 14.1%; adjusted OR, 4.01; 95% CI, 3.30 to 4.89), and placement of a percutaneous feeding tube (7.3% vs. <0.3%; adjusted OR, 88.9; 95% CI, 21.6 to 366).

The results highlight the importance of dysphagia screening for all patients with acute ischemic stroke, according the study authors. They wrote, “Failing a dysphagia screening test is a potent predictor of poor outcome, even among patients with mild strokes, who are at particular risk of not being screened. Clinicians and health administrators should be aware of the critical need for dysphagia screening after acute stroke, regardless of stroke severity.”

Reperfusion associated with better outcomes even in patients with large strokes

Acute ischemic stroke patients with large lesion volumes had more favorable outcomes and no greater risk of hemorrhage if they had successful reperfusion with mechanical thrombectomy, a study found.

Researchers used data collected between January 2012 and August 2015 by a prospective clinical registry of consecutive acute ischemic stroke patients receiving mechanical thrombectomy. They focused on patients with large lesions, defined as those with pretreatment diffusion-weighted imaging (DWI)-Alberta Stroke Program Early Computed Tomography Score (ASPECTS) ≤6. All patients had internal carotid artery or middle cerebral artery occlusions. The primary end point was a favorable outcome, defined as a modified Rankin scale score ≤2 at 90 days.

The analysis included 218 patients, of whom 66% had successful reperfusion at the end of mechanical thrombectomy. The successfully reperfused patients had a significantly higher rate of favorable outcomes (38.7% vs. 17.4%; P=0.002) than those without successful reperfusion. They also had lower mortality at three months (22.5% vs. 39.1%; P=0.013). Both groups had similar rates of intracranial hemorrhage (13.0% vs. 14.1%). Results were published online by Stroke on Feb. 24.

In the subgroup of patients with particularly large lesions (DWI-ASPECTS <5), favorable outcomes were low and mortality was high, regardless of successful reperfusion (13.0% vs. 9.5% and 45.7% vs 57.1%, respectively). In this group, there was a trend toward better outcomes associated with successful reperfusion, however, the authors noted. They concluded that successful reperfusion is associated with reduced mortality and disability in patients with a score of 5 or 6 and that more data are needed to clarify the potential effects in patients with lower scores.

The findings differ from previous studies, which found increased risks of intracranial hemorrhage and mortality with reperfusion in patients with large strokes, the authors noted. The results of this study “suggest that successful reperfusion may prevent DWI lesion growth, avoiding malignant infarction evolution responsible for mortality,” they wrote. The risk of hemorrhage seems to be associated with initial stroke severity rather than early reperfusion status, according to the study authors, who called for additional research to confirm their conclusion that “large DWI lesion volumes should not preclude patients from reperfusion therapies,” including tissue plasminogen activator and mechanical thrombectomy.

IV hydration noninferior to no prophylaxis for contrast-induced nephropathy

IV hydration was noninferior to no prophylaxis for prevention of contrast-induced nephropathy, as well as less cost-effective, a recent study found.

Researchers at a single center in the Netherlands performed a randomized, phase 3, parallel-group, open-label, noninferiority trial in patients at high risk for contrast-induced nephropathy to determine whether guideline-recommended IV hydration with saline outperformed no prophylaxis. Patients with an estimated glomerular filtration rate (eGFR) of 30 to 59 mL per minute/1.73 m2 who underwent an elective procedure that required administration of IV contrast material were assigned to receive 0.9% saline via IV or no prophylaxis. Patients with an eGFR below 30 mL/min/1.73 m2 were excluded, as were those who had previously had dialysis and those who had not been referred for IV hydration. The study's primary outcome was contrast-induced nephropathy, defined as more than a 25% increase or an increase of 44 µmol/L (0.5 mg/dL) in serum creatinine from baseline within two to six days of exposure to contrast, as well as cost-effectiveness of no prophylaxis versus IV hydration. The study results were published online Feb. 20 by The Lancet and appear in the April 1 issue.

A total of 660 patients were randomly assigned to no prophylaxis or IV hydration between June 17, 2014, and July 17, 2016. Mean age was 72.2 years, and most participants (62%) were men. Three hundred thirty-two patients were assigned to receive no prophylaxis, and 328 were assigned to IV hydration (170 received a short hydration protocol, while 158 received a long hydration protocol; the mean total intravenous hydration volume was 1,637 mL). Values for serum creatinine at days two to six were available for 307 (92%) of patients in the no prophylaxis group and 296 (90%) of patients in the IV hydration group. Mean change from days two to six was 0.31 µmol/L (0.003 mg/dL) in the IV hydration group and 1.30 µmol/L (0.014 mg/dL) in the no hydration group. Eight patients in each group had contrast-induced nephropathy (2.6% vs. 2.7%, respectively), and 18 patients in the IV hydration group (5.5%) experienced treatment-related complications. Not administering prophylaxis was found to save costs compared with hydration, mainly due to reduced hospitalization costs.

The researchers noted that their cost analysis applied only to the Netherlands and might be different in other countries. In addition, they pointed out that their study was done at only one center, that participants were not blinded, and that patients with emergent conditions and those in intensive care were excluded, among other limitations. Also, only 9% were inpatients, and all procedures were done using minimum-volume, pre-warmed, low-osmolar, monomer, non-ionic, contrast material. However, they concluded that prophylactic IV hydration for contrast-induced nephropathy does not appear to be superior to no prophylaxis and may be less cost-effective. They also noted that some of the patients in their study who were assigned to IV hydration developed treatment-related complications. “Based on these findings and assuming optimal contrast media administration, withholding prophylaxis for high-risk patients with eGFR higher than 29 mL/min/1.73 m2 might be considered without compromising patient safety,” they wrote.

COPD, heart failure, MI patients with marginal need for ICU had no better survival there

Admitting more patients with chronic obstructive pulmonary disease (COPD), heart failure, or acute myocardial infarction to the ICU was not associated with reduced mortality, a recent study found.

The retrospective cohort study included 1.5 million fee-for-service Medicare beneficiaries admitted to a hospital for an exacerbation of COPD or heart failure or a myocardial infarction between 2010 and 2012. Overall, 31% were admitted to the ICU. Researchers used an instrumental variable analysis to focus specifically on “marginal” patients, whose need for ICU admission was borderline, discretionary, or of uncertain benefit. The instrumental variable analysis used the difference between the distance from a patient's residence to the nearest high-ICU-use hospital and the distance from a patient's residence to the nearest hospital of any type and “marginal patients” were those who appeared to have been admitted to the ICU only because they lived closer to a hospital with high ICU use.

With the instrumental analysis, researchers found that ICU admission was not associated with a significant difference in 30-day mortality for any of the conditions. ICU admission was associated with greater hospital costs for heart failure ($11,793 vs. $9,185) and acute myocardial infarction ($19,513 vs. $14,590), but not COPD. Based on the results, the authors concluded that ICU admission did not confer a survival benefit for hospitalized patients with these conditions and uncertain need for ICU care. The study was published by Annals of the American Thoracic Society on Feb. 17 and appear in the June 1 issue.

The results contrast with a recent study finding significantly better survival and similar costs among “marginal” pneumonia patients admitted to the ICU instead of the general ward, the authors noted. The difference between the studies might be explained by factors specific to the conditions, including that pneumonia may progress to sepsis or lead to decompensation. “While pneumonia patients with uncertain ICU needs may obtain a survival advantage with ICU admission, this pattern appears to be condition-specific . . . Identifying these patients who do not benefit from ICU admission could reduce costs while improving healthcare efficiency,” the authors wrote.

The study's findings apply only to patients whose likelihood of admission to the ICU depended on the practices of the nearest hospital, not those who clearly do or don't require ICU-level care, the authors cautioned. However, they calculated that 20% to 25% of patients hospitalized with heart failure or acute myocardial infarction might be in this group. A limitation of the study was that it could not identify the specific characteristics of these “marginal” patients. Because the study included only Medicare beneficiaries, the results may also not be generalizable to younger patients.

Inpatient mortality from major bleeds lower in patients on DOACs than warfarin

A recent cohort study found differences in treatment and outcomes of major bleeding between patients taking warfarin and those taking direct oral anticoagulants (DOACs).

Patients had atrial fibrillation or flutter, were 66 years of age or older, and presented to one of five tertiary care hospitals in Ontario, Canada, with oral anticoagulant-related major bleeding (exposure to dabigatran, rivaroxaban, apixaban, or warfarin within three days of presentation). The primary outcome was treatment strategy during the course of the hospital encounter, and secondary outcomes were in-hospital and 30-day mortality. Researchers included 2,002 cases (460 DOAC and 1,542 warfarin) involving 1,799 patients in their analysis. Results were published online in February by Chest.

Among DOAC cases, 245 (53.3%) involved dabigatran, 155 (33.7%) involved rivaroxaban, and 60 (13.0%) involved apixaban. Patients were 81.2 years old on average, had a mean CHA2DS2-VASc score of 4.4, and had a median HAS-BLED score of 3.

Intracranial hemorrhages, especially subdural hematomas, comprised a higher proportion of major bleeding in patients taking warfarin compared to those taking DOACs (29.8% vs. 21.9%, P<0.001 for all intracranial bleeds). A higher proportion of gastrointestinal bleeding, especially in the lower gastrointestinal tract, was seen in the DOAC cohort (61.7% vs. 42.5%, P<0.001, for all gastrointestinal bleeds). Fewer DOAC patients required transfusion of blood products than those on warfarin (278 [60.4%] vs. 1,014 [65.8%]; adjusted risk ratio [RR], 0.92, 95% CI, 0.85 to 1.00). Reflecting the gastrointestinal-predominant bleeding pattern, packed red blood cells were most frequently used in DOAC-related events, whereas prothrombin complex concentrate, vitamin K, and fresh frozen plasma were used more in cases involving warfarin.

Overall, 9.8% of patients in the DOAC cohort and 15.2% of those in the warfarin cohort died in the hospital (P<0.0001). The adjusted RR for inpatient mortality was 0.66 (95% CI, 0.49 to 0.89) for DOAC-related major bleeds compared to warfarin. There were no significant differences in all-cause 30-day mortality between groups (12.6% for DOAC bleeds vs. 16.3% for warfarin bleeds; adjusted RR, 0.79; 95% CI, 0.61 to 1.03).

The study authors noted limitations, such as how the outcomes may not apply to settings other than regional referral centers and that the observational design is prone to immortal time bias and confounding by indication (patients on warfarin who died prior to the study start date were excluded). In addition, the study population was limited to patients undergoing thromboprophylaxis for atrial fibrillation.

The lower in-hospital mortality rate seen with DOACs compared to warfarin (despite high rates of warfarin reversal) is consistent with previous clinical trial findings, the authors noted. “This . . . suggests patients on these novel agents do not suffer excess harm compared to warfarin in the real-world context, even with the lack of specific antidotes,” they wrote. “Our findings will serve as useful baseline data for comparison of effectiveness and cost-effectiveness of drug-specific reversal agents to guide their optimal use.”