idweek 770 cddep 48x96 abstract2 submitted 10 15 12 0

1
RESEARCH POSTER PRESENTATION DESIGN © 2012 www.PosterPresentations.com Describe patterns of changing antibiotic therapy for different infection sites Determine the effect of culture and imaging studies on the likelihood of de7escalation, controlling for patient history, comorbidities and parameters of infection at the time of starting and stopping antibiotics. Background: Use of patient-specific culture data to optimize empiric therapy is a cornerstone of rational hospital antibiotic use. The frequency with which cultures are obtained and therapy tailored to results is unknown. Methods: We performed a cross-sectional study using retrospective chart review of 1,200 adult inpatients, hospitalized >24hrs, with >=1 active antibiotic order. Patients were enrolled for 4 index dates at quarterly intervals during a 1-year study period (9/2009-10/2010). Infectious disease (ID) specialists recorded demographics, comorbidities, antibiotic therapy, imaging studies and culture results in a 17d window, and categorized changes to therapy. No change was defined as the continuation of the course as initially ordered; de-escalation was a change resulting in narrower coverage; escalation was a switch to/addition of an antibiotic resulting in broader coverage. A Cox proportional hazard model stratified by infection site was used to model time to de-escalation. Patients receiving <=1 antibiotic prescription and/or exclusively prophylactic courses were excluded from the analysis. Results: Of 1,200 charts that were reviewed, 631 patients(52.6%) were included in the analysis. Of these, 288 (45.7%) were not changed, 192 (30.4%) were de-escalated and 151 (24%) were escalated. De- escalated prescriptions included 18 fully discontinued courses (2.85%), 61 de-escalations without culture results (9.7%), and 113 de- escalations based on cultures (17.9%). The no-change category included 250 continued as initially ordered (39.6%) and 38 switches to equivalent antibiotics (6%). De-escalation was most common for urinary infections (46%). Patients that received fewer prescriptions, were started on broad-spectrum antibiotics, had elevated WBC at start of course, shorter pre-therapy LOS had higher probability of de- escalation. However, positive culture and imaging study had no significant effect. Conclusion: Although patients with suspected infections were frequently cultured, clinicians changed antibiotics in less than half of patients receiving multiple therapies. Availability of positive culture and/or imaging study suggestive of infection did not have a significant impact on de- escalation probability. Speci;ication of Cox proportional hazard model: Co7variates retained after univariate analysis of the association between de7escalation and patient history, antibiotic use and infection parameters if P<0.15. Site of infection and presence of relevant diagnostic information (i.e., positive culture or imaging study suggestive of infection as determined by chart reviewer) kept in all tested models RESULTS Over 45% of patients in the hospital on antibiotics continue on their course without change. Of the 30% of patients who have their antibiotic de<escalated, this occurs on average after 4.7 days of antibiotics. Patients more likely to have their antibiotics de< escalated were: Started on vancomycin, pipracillin/tazobactam or levo;loxacin Receiving fewer antibiotics Aged 51765 Had an elevated WBC at start of antibiotics that normalized Being treated for a presumed urinary tract infection Presence of positive culture or imaging data suggestive of infection did not impact de<escalation Class Rank 1G cephalosporins, an01staph pens, metronidazole (CDI) 1 Fluoroquinolones, ESP macrolides, amoxi1clav, 3G cephalosporins, oral vancomycin (CDI) 2 An0pseudomonal penicillins, cefepime, vancomycin 3 Carbapenems, colis0n, 0gecycline, linezolid, daptomycin 4 Change N % Time of change (mean) LOS (mean) Abx count (mean) Age (mean) Had culture collected (N) Relevant culture (% of cases) Number of cultures collected (mean) Had imaging study (N) Number of imaging studies (mean) Relevant imaging study (%) De1escala0on 192 30.43% 4.7 12.4 2.9 63.5 174 52% 4.08 174 2.53 42% Escala0on 151 23.93% 5.9 27.1 3.3 63.6 144 50% 6.21 146 2.64 53% No change 288 45.64% 5.6 18.1 2.5 64.9 267 39% 4.30 265 2.23 50% Total 631 100.00% 5.2 18.5 2.8 64.2 585 46% 4.69 585 2.42 48% Site N % Day of change (mean) Respiratory (RTI) 200 100.00% 4.9 De1escala0on 55 27.50% 4.9 Escala0on 46 23.00% 4.6 No change 99 49.50% 6.1 Skin and soP Qssue (SSTI) 95 100.00% 6.0 De1escala0on 22 23.16% 4.5 Escala0on 26 27.37% 7.5 No change 47 49.47% 4.7 GastrointesQnal 90 100.00% 5.0 De1escala0on 31 34.44% 4.4 Escala0on 23 25.56% 5.7 No change 36 40.00% 5.6 Urinary (UTI) 74 100.00% 3.7 De1escala0on 34 45.95% 4.1 Escala0on 15 20.27% 3.3 No change 25 33.78% 2.8 Bloodstream (BSI) 70 100.00% 6.1 De1escala0on 25 35.71% 5.4 Escala0on 15 21.43% 7.8 No change 30 42.86% 4.3 Other 40 100.00% 5.5 De1escala0on 9 22.50% 4.2 Escala0on 12 30.00% 6.4 No change 19 47.50% 6.0 Prophylaxis 62 100.00% 6.7 De1escala0on 16 25.81% 5.2 Escala0on 14 22.58% 7.4 No change 32 51.61% 14.0 Daniel Morgan, MD, MS 1 , Birgir Johannsson, MD 2 , Marin Schweizer, PhD 2 , Nikolay Braykov, BSE 3 , Scott A. Weisenberg, MD, MSc, DTM&H 4 , Daniel Z. Uslan, MD, MS 5 , Theodoros Kelesidis, MD 6 , Heather Young, MD 7 , Joseph Cantey, MD 8 , Edward Septimus, MD, FIDSA, FSHEA 9,10 , Arjun Srinivasan, MD, FSHEA 11 , Eli Perencevich, MD, MS, FIDSA, FSHEA 2 and Ramanan Laxminarayan, PhD, MPH 3,12,13 , (1)Department of Epidemiology and Public Health, University of Maryland School of Medicine, Baltimore, MD, (2)Department of Medicine, University of Iowa Carver College of Medicine, Iowa City, IA, (3)Center for Disease Dynamics, Economics & Policy, Washington, DC, (4)Alta Bates Summit Medical Center, Oakland, CA, (5)Infectious Diseases, David Geffen School of Medicine/University of California, Los Angeles, Los Angeles, CA, (6)David Geffen School of Medicine at UCLA, Los Angeles, CA, (7)Infectious Diseases, Denver Health Medical Center, Denver, CO, (8)Pediatrics, University of Texas Southwestern Medical Center, Dallas, TX, (9)Clinical Services Group, HCA Inc, Nashville, TN, (10) Texas A&M Health Sciences Center, Houston, TX, (11)Centers for Disease Control and Prevention, Atlanta, GA, (12)Public Health Foundation of India, New Delhi, India, (13)Princeton Environmental Institute, Princeton University, Princeton, NJ The Frequency Of Antibiotic De-Escalation Over Six US Hospitals: Results from a Multicenter Cross-Sectional Study Poster 770 IDWeek 2012 Nikolay Braykov 1616 P St NW Suite 400 Washington, DC 20036 (202) 328 5170 [email protected] ABSTRACT (revised) OBJECTIVES METHODS RESULTS (continued) CONTACT INFORMATION PopulaQon: inpa0ents at 6 hospitals: Veterans Affairs (n=1), teaching (n =2) and non1teaching (n=3) Study period: 4 index dates chosen at equal intervals 9/2009 1 10/2010 (11/20, 2009; 2/10, 2010; 10/20, 2010, 8/10, 2010) Inclusion: pa0ents with ac0ve order for an0bio0c prescrip0on on index date Exclusion: ambulatory (LOS <24 hrs), pediatric (age <18yrs) and psychiatric admissions 1,200 paQents (50 per date per facility) InfecQous Disease Physician Chart Review: Pa0ent history and allergies Indica0ons for an0bio0cs, start/stop dates for <9 ABX <6 admission ICD9 codes (Charlson comorbidity score) Microbiology reports (14d window) Radiology reports (3d window) Infec0on parameters (fever and WBC) For all paQents on >1 non]prophylacQc ABX and LOS>=3d NO CHANGE: con0nued as ini0ally ordered or switch to equivalent ESCALATION: addi0on of Rx and/or switch1> increase in spectrum DE]ESCALATION: switch to targeted therapy and/or change in number and/or spectrum 1>decrease in spectrum Included de]escalated w culture, de]escalated w/o culture, disconQnuaQon of all anQbioQcs Daniel J Morgan, MD, MS 685 W. Baltimore St., MSTF 334 Baltimore, MD 410770671734 [email protected] Variable Hazard raQo (HR) P]value 95% Confidence Interval (CI) Number of an0bio0cs 0.83 0.026 [0.70]0.98] Severe comorbidi0es (Charlson score >2) 0.82 0.273 [0.5711.17] Age (51165 years) (Reference: all other age categories) 1.43 0.028 [1.04]1.97] ICU 0.74 0.1 [0.51]1.1] Start on vancomycin, pip/taz or levofloxacin 1.63 0.01 [1.13]2.37] Elevated WBC at start 1.33 0.087 [0.96]1.85] Elevated WBC at stop of first course 0.61 0.013 [0.41]0.90] Fever present at start 0.77 0.122 [0.5511.07] LOS prior to first an0bio0c 0.99 0.048 [0.98]1] Relevant (posi0ve) culture 1.03 0.868 [0.7511.42] Relevant imaging study 0.77 0.149 [0.5411.10] Infec0on site (Reference 1 Gastrointes0nal) Bloodstream 0.77 0.403 [0.4211.42] Other 0.76 0.525 [0.3211.78] Prophylaxis 0.92 0.817 [0.4711.83] Respiratory 1.28 0.375 [0.7412.21] Skin and soj 0ss 0.87 0.635 [0.5011.54] Urinary tract 1.73 0.069 [0.96]3.12] Table 4: Cox proporQonal hazard model for factors related to Qme to de]escalaQon compared to paQents with no change in anQbioQcs (N= 367) CONCLUSIONS Table 2: Changes to anQbioQc therapy for paQents receiving >1 anQbioQc prescripQon (N= 631) Table 3: De]escalaQon paferns by primary site of infecQon (N= 631) Note: Other infec0ons incl. CNS, unspecified fevers and leukocytosis. Time of change for no change group defined as hospital day of discharge or discon0nua0on of all therapy (whichever came first); Note: Time at risk was defined as the interval between start of earliest an0bio0c and de1escala0on (failure event) and discon0nua0on of therapy and/ or discharge (whichever came first). Exclusion : 440 patients (36.7%) were excluded because they received <2 antibiotics 129 patients (10.8%) on >=2 antibiotics, LOS<3 days or had received exclusively prophylactic courses 0 .2 .4 .6 .8 1 Probability of no deescalation 0 5 10 15 20 25 Hospital days after start of therapy RTICxR w infection RTINo CxR UTICulture present UTINo relevant culture Figure 1: Cox proporQonal hazard model of UTI (red) and respiratory tract infecQon (blue) de]escalaQon probability, with and without diagnosQc informaQon (no differences p<0.10) Table 1: Grouping of anQbioQcs by spectrum of acQvity, used to define de]escalaQon

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•  Describe(patterns(of(changing(antibiotic(therapy(for(different(infection(sites(

•  Determine(the(effect(of(culture(and(imaging(studies(on(the(likelihood(of(de7escalation,(controlling(for(patient(history,(comorbidities(and(parameters(of(infection(at(the(time(of(starting(and(stopping(antibiotics.((

Background: Use of patient-specific culture data to optimize empiric therapy is a cornerstone of rational hospital antibiotic use. The frequency with which cultures are obtained and therapy tailored to results is unknown.   Methods: We performed a cross-sectional study using retrospective chart review of 1,200 adult inpatients, hospitalized >24hrs, with >=1 active antibiotic order. Patients were enrolled for 4 index dates at quarterly intervals during a 1-year study period (9/2009-10/2010). Infectious disease (ID) specialists recorded demographics, comorbidities, antibiotic therapy, imaging studies and culture results in a 17d window, and categorized changes to therapy. No change was defined as the continuation of the course as initially ordered; de-escalation was a change resulting in narrower coverage; escalation was a switch to/addition of an antibiotic resulting in broader coverage. A Cox proportional hazard model stratified by infection site was used to model time to de-escalation. Patients receiving <=1 antibiotic prescription and/or exclusively prophylactic courses were excluded from the analysis.   Results: Of 1,200 charts that were reviewed, 631 patients(52.6%) were included in the analysis. Of these, 288 (45.7%) were not changed, 192 (30.4%) were de-escalated and 151 (24%) were escalated. De-escalated prescriptions included 18 fully discontinued courses (2.85%), 61 de-escalations without culture results (9.7%), and 113 de-escalations based on cultures (17.9%). The no-change category included 250 continued as initially ordered (39.6%) and 38 switches to equivalent antibiotics (6%). De-escalation was most common for urinary infections (46%). Patients that received fewer prescriptions, were started on broad-spectrum antibiotics, had elevated WBC at start of course, shorter pre-therapy LOS had higher probability of de-escalation. However, positive culture and imaging study had no significant effect. Conclusion: Although patients with suspected infections were frequently cultured, clinicians changed antibiotics in less than half of patients receiving multiple therapies. Availability of positive culture and/or imaging study suggestive of infection did not have a significant impact on de-escalation probability.

Speci;ication(of(Cox(proportional(hazard(model:(•  Co7variates(retained(after(univariate(analysis(of(the(association(between(de7escalation(and(patient(history,(antibiotic(use(and(infection(parameters(if(P<0.15.(

•  Site(of(infection(and(presence(of(relevant(diagnostic(information((i.e.,(positive(culture(or(imaging(study(suggestive(of(infection(as(determined(by(chart(reviewer)(kept(in(all(tested(models(

RESULTS

•  Over%45%%of%patients%in%the%hospital%on%antibiotics%continue%on%their%course%without%change.%Of%the%30%%of%patients%who%have%their%antibiotic%de<escalated,%this%occurs%on%average%after%4.7%days%of%antibiotics.%

•  Patients%more%likely%to%have%their%antibiotics%de<escalated%were:%•  Started(on(vancomycin,(pipracillin/tazobactam(or(

levo;loxacin(•  Receiving(fewer(antibiotics(•  Aged(51765(•  Had(an(elevated(WBC(at(start(of(antibiotics(that(

normalized(•  Being(treated(for(a(presumed(urinary(tract(

infection(•  Presence%of%positive%culture%or%imaging%data%suggestive%of%infection%did%not%impact%de<escalation%Class% Rank%

1G#cephalosporins,#an01staph#pens,#metronidazole#(CDI)# 1#

Fluoroquinolones,#ESP#macrolides,#amoxi1clav,#3G#cephalosporins,#oral#vancomycin#(CDI)# 2#

An0pseudomonal#penicillins,#cefepime,#vancomycin# 3#

Carbapenems,#colis0n,#0gecycline,#linezolid,#daptomycin# 4#

Change% N% %%Time%of%change%(mean)%

LOS%(mean)%

Abx%count%(mean)%

Age%(mean)%

Had%culture%collected%(N)%

Relevant%culture%(%%of%cases)%

Number%of%cultures%collected%(mean)%

Had%imaging%study%(N)%

Number%of%imaging%studies%(mean)%

Relevant%imaging%study%(%)%

De1escala0on# 192# 30.43%# 4.7# 12.4# 2.9# 63.5# 174# 52%# 4.08# 174# 2.53# 42%#Escala0on# 151# 23.93%# 5.9# 27.1# 3.3# 63.6# 144# 50%# 6.21# 146# 2.64# 53%#No#change# 288# 45.64%# 5.6# 18.1# 2.5# 64.9# 267# 39%# 4.30# 265# 2.23# 50%#Total% 631% 100.00%% 5.2% 18.5% 2.8% 64.2% 585% 46%% 4.69% 585% 2.42% 48%%

Site% N% %% Day%of%change%(mean)%

%Respiratory%(RTI)% 200% 100.00%% 4.9%De1escala0on# 55# 27.50%# 4.9#Escala0on# 46# 23.00%# 4.6#No#change# 99# 49.50%# 6.1#Skin%and%soP%Qssue%(SSTI)% 95% 100.00%% 6.0%De1escala0on# 22# 23.16%# 4.5#Escala0on# 26# 27.37%# 7.5#No#change# 47# 49.47%# 4.7#GastrointesQnal% 90% 100.00%% 5.0%De1escala0on# 31# 34.44%# 4.4#Escala0on# 23# 25.56%# 5.7#No#change# 36# 40.00%# 5.6#Urinary%(UTI)% 74% 100.00%% 3.7%De1escala0on# 34# 45.95%# 4.1#Escala0on# 15# 20.27%# 3.3#No#change# 25# 33.78%# 2.8#Bloodstream%(BSI)% 70% 100.00%% 6.1%De1escala0on# 25# 35.71%# 5.4#Escala0on# 15# 21.43%# 7.8#No#change# 30# 42.86%# 4.3#Other% 40% 100.00%% 5.5%De1escala0on# 9# 22.50%# 4.2#Escala0on# 12# 30.00%# 6.4#No#change# 19# 47.50%# 6.0#Prophylaxis% 62% 100.00%% 6.7%De1escala0on# 16# 25.81%# 5.2#Escala0on# 14# 22.58%# 7.4#No#change# 32# 51.61%# 14.0#

Daniel Morgan, MD, MS1, Birgir Johannsson, MD2, Marin Schweizer, PhD2, Nikolay Braykov, BSE3, Scott A. Weisenberg, MD, MSc, DTM&H4, Daniel Z. Uslan, MD, MS5, Theodoros Kelesidis, MD6, Heather Young, MD7, Joseph Cantey, MD8, Edward Septimus, MD, FIDSA, FSHEA9,10, Arjun Srinivasan, MD, FSHEA11, Eli Perencevich, MD, MS, FIDSA, FSHEA2 and Ramanan Laxminarayan, PhD, MPH3,12,13, (1)Department of Epidemiology and Public Health, University of Maryland School of Medicine, Baltimore, MD, (2)Department of Medicine, University of Iowa Carver College of

Medicine, Iowa City, IA, (3)Center for Disease Dynamics, Economics & Policy, Washington, DC, (4)Alta Bates Summit Medical Center, Oakland, CA, (5)Infectious Diseases, David Geffen School of Medicine/University of California, Los Angeles, Los Angeles, CA, (6)David Geffen School of Medicine at UCLA, Los Angeles, CA, (7)Infectious Diseases, Denver Health Medical Center, Denver, CO, (8)Pediatrics, University of Texas Southwestern Medical Center, Dallas, TX, (9)Clinical Services Group, HCA Inc, Nashville, TN, (10) Texas A&M Health Sciences

Center, Houston, TX, (11)Centers for Disease Control and Prevention, Atlanta, GA, (12)Public Health Foundation of India, New Delhi, India, (13)Princeton Environmental Institute, Princeton University, Princeton, NJ

The Frequency Of Antibiotic De-Escalation Over Six US Hospitals: Results from a Multicenter Cross-Sectional Study

Poster 770 IDWeek 2012

Nikolay Braykov 1616 P St NW Suite 400 Washington, DC 20036

(202) 328 5170 [email protected]

ABSTRACT (revised)

OBJECTIVES

METHODS RESULTS (continued)

CONTACT INFORMATION

PopulaQon:%inpa0ents#at#6#hospitals:#Veterans#Affairs#(n=1),#teaching#(n#=2)#and#non1teaching#(n=3)#

Study%period:%4#index#dates#chosen#at#equal#intervals#9/2009#1#10/2010#(11/20,#2009;#2/10,#2010;#10/20,#2010,#8/10,#2010)#

Inclusion:%pa0ents#with#ac0ve#order#for#an0bio0c#prescrip0on#on#index#date#

Exclusion:%#ambulatory#(LOS#<24#hrs),#pediatric#(age#<18yrs)#and#psychiatric#admissions#

1,200%paQents%(50#per#date#per#facility)%InfecQous%Disease%Physician%Chart%Review:%

Pa0ent##history#and#allergies##Indica0ons#for#an0bio0cs,#start/stop#dates#for#<9#ABX####<6#admission#ICD9#codes#(Charlson#comorbidity#score)#

Microbiology#reports#(14d#window)##Radiology#reports#(3d#window)##

Infec0on#parameters#(fever#and#WBC)#

For%all%paQents%on%>1%non]prophylacQc%ABX%and%LOS>=3d%#

##NO%CHANGE:##

con0nued#as#ini0ally#ordered#or#switch#to#equivalent#ESCALATION:#

#addi0on#of#Rx#and/or#switch1>##increase#in#spectrum##DE]ESCALATION:%#

switch#to#targeted#therapy#and/or#change#in#number#and/or#spectrum#1>decrease#in#spectrum#

Included#de]escalated%w%culture,%de]escalated%w/o%culture,%disconQnuaQon%of%all%anQbioQcs%

Daniel%J%Morgan,%MD,%MS%685 W. Baltimore St., MSTF 334 Baltimore,(MD(410770671734([email protected](

Variable% Hazard%raQo%(HR)% P]value%

95%%Confidence%Interval%(CI)%

Number#of#an0bio0cs# 0.83% 0.026% [0.70]0.98]%Severe#comorbidi0es#(Charlson#score#>2)# 0.82# 0.273# [0.5711.17]#Age#(51165#years)#(Reference:#all#other#age#categories)# 1.43% 0.028% [1.04]1.97]%ICU# 0.74% 0.1% [0.51]1.1]%Start#on#vancomycin,#pip/taz#or#levofloxacin# 1.63% 0.01% [1.13]2.37]%Elevated#WBC#at#start# 1.33% 0.087% [0.96]1.85]%Elevated#WBC#at#stop#of#first#course# 0.61% 0.013% [0.41]0.90]%Fever#present#at#start# 0.77# 0.122# [0.5511.07]#LOS#prior#to#first#an0bio0c# 0.99% 0.048% [0.98]1]%Relevant#(posi0ve)#culture# 1.03# 0.868# [0.7511.42]#Relevant#imaging#study# 0.77# 0.149# [0.5411.10]#Infec0on#site#(Reference#1#Gastrointes0nal)#

Bloodstream# 0.77# 0.403# [0.4211.42]#Other# 0.76# 0.525# [0.3211.78]#Prophylaxis# 0.92# 0.817# [0.4711.83]#Respiratory# 1.28# 0.375# [0.7412.21]#Skin#and#soj#0ss# 0.87# 0.635# [0.5011.54]#Urinary#tract# 1.73% 0.069% [0.96]3.12]%

Table%4:%Cox%proporQonal%hazard%model%for%factors%related%to%Qme%to%de]escalaQon%compared%to%paQents%with%no%change%in%anQbioQcs%(N=%367)%

CONCLUSIONS

Table%2:%Changes%to%anQbioQc%therapy%for%paQents%receiving%>1%anQbioQc%prescripQon%(N=%631)%

Table%3:%De]escalaQon%paferns%by%primary%site%of%infecQon%(N=%631)%

Note:#Other#infec0ons#incl.#CNS,#unspecified#fevers#and#leukocytosis.##Time#of#change#for#no#change#group#defined#as#hospital#day#of#discharge#or#discon0nua0on#of#all#therapy#(whichever#came#first);#

Note:#Time#at#risk#was#defined#as#the#interval#between#start#of#earliest#an0bio0c#and#de1escala0on#(failure#event)#and#discon0nua0on#of#therapy#and/or#discharge#(whichever#came#first).##

Exclusion:(•  440(patients((36.7%)(were(excluded(because(they(received(<2(antibiotics(

•  129(patients((10.8%)(on(>=2(antibiotics,(LOS<3(days(or(had(received(exclusively(prophylactic(courses(

0.2

.4.6

.81

Prob

abilit

y of

no

de−e

scal

atio

n

0 5 10 15 20 25Hospital days after start of therapy

RTI−CxR w infection RTI−No CxRUTI−Culture present UTI−No relevant culture

Figure%1:%Cox%proporQonal%hazard%model%of%UTI%(red)%and%respiratory%tract%infecQon%(blue)%de]escalaQon%probability,%with%and%without%diagnosQc%informaQon%(no%differences%p<0.10)%

Table%1:%Grouping%of%anQbioQcs%by%spectrum%of%acQvity,%used%to%define%de]escalaQon%

Nikolay Braykov