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Richard S.C. Kerr, Julia A. Yarnold and Mary SneadeJane Wolstenholme, Oliver Rivero-Arias, Alastair Gray, Andrew J. Molyneux,
Surgical Clipping After aSAHTreatment Pathways, Resource Use, and Costs of Endovascular Coiling Versus
ISSN: 1524-4628 Copyright © 2007 American Heart Association. All rights reserved. Print ISSN: 0039-2499. OnlineStroke is published by the American Heart Association. 7272 Greenville Avenue, Dallas, TX 72514
doi: 10.1161/STROKEAHA.107.4825702008, 39:111-119: originally published online November 29, 2007Stroke
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Treatment Pathways, Resource Use, and Costs ofEndovascular Coiling Versus Surgical Clipping After aSAHJane Wolstenholme, PhD; Oliver Rivero-Arias, MSc; Alastair Gray, PhD; Andrew J. Molyneux, FRC;
Richard S.C. Kerr, FRCS; Julia A. Yarnold, FCR; Mary Sneade, BA (Hons); on behalf of theInternational Subarachnoid Aneurysm Trial (ISAT) Collaborative Group
Background and Purpose—The International Subarachnoid Aneurysm Trial (ISAT) reported that endovascular coilingyields better clinical outcomes than surgical clipping at 1 year. The high cost of the consumables associated with theendovascular coiling procedure (particularly the coils) led health care purchasers to conclude that coiling was a morecostly procedure overall. To examine this assumption and provide evidence for future policy, accurate andcomprehensive data are required on the overall resource usage and cost of each strategy.
Methods—We provide detailed results of patient treatment pathways, resource utilization, and costs up to 24 monthspostrandomization for endovascular and neurosurgical treatment of aSAH. We report data on costs related to initial andsubsequent procedures (ward days, ITU, equipment, staff, consumables, etc), adverse events, complications, and followup. The data are based on a subsample of all patients randomized in ISAT, containing all patients across 22 UK centers(n�1644).
Results—There was a nonsignificant difference �£1740 (�£3582 to £32) in the total 12-month cost of treatment in favorof endovascular treatment. Endovascular patients had higher costs than neurosurgical patients for the initial procedure,for the number and length of stay of subsequent procedures, and for follow-up angiograms. These were more than offsetby lower costs related to length of stay for the initial procedure. In the following 12- to 24-month period, costs forsubsequent procedures, angiograms, complications, and adverse events were greater for the endovascular patients,reducing the difference in total per patient cost to �£1228 (�£3199 to £786) over the first 24 months of follow-up.
Conclusions—No significant difference in costs between the endovascular and neurosurgery groups existed at 12- or24-month follow up. (Stroke. 2008;39:111-119.)
Key Words: aneurysm � costs � economics � subarachnoid hemorrhage
Aneurysmal subarachnoid hemorrhage (aSAH) is amajor cause of death and severe disability in rela-
tively young patients (mean age 52), with an annualincidence of 6 to 12 per 100 000 in Western countries.1
The natural history of the disease suggests that 30% ofpatients will die within 24 hours of the bleed and a further25% to 30% of patients will rebleed and die over the next4 weeks if no treatment is adopted.2 50% of survivors willbe dead by 6 months without treatment.3
Until 1992, when the Guglielmi detachable platinum coil(GDC) was introduced to Europe, there was no alternative tocraniotomy and neurosurgical clipping to secure the aneu-rysm and prevent rebleeding. In 2002 ISAT, a large MRC-funded prospective randomized controlled trial, reported thatendovascular coiling yields better clinical outcomes thansurgical clipping at 1 year, and these results have significantlychanged clinical practice in both UK and overseas centers.4,5
The high cost of the consumables associated with theendovascular coiling procedure (particularly the coils) ledhospitals and health care purchasers to conclude that coilingwas a much more costly procedure overall. To examine thisassumption and provide a better evidence base for futurepolicy, accurate and comprehensive data were required on theoverall resource usage and cost of each strategy. Non–healthcare costs associated with each procedure are also likely to beimportant: long-term care for dependent survivors may be asubstantial cost driver given the high prevalence of relativelyyoung patients with severe disabilities in the treatmentpopulation, whereas any differences between treatments inemployment status after aSAH may have wider social impor-tance and may influence patient attitudes. Finally, detailedcost information is an essential prerequisite to calculating theincremental cost-effectiveness of coiling compared withclipping.
Received February 28, 2007; final revision received June 6, 2007; accepted June 13, 2007.From the Health Economics Research Centre (J.W., O.R.-A., A.G.), Department of Public Health, University of Oxford, UK; and the Neurovascular
Research Unit (A.J.M., R.S.C.K., J.A.Y., M.S.), Nuffield Department of Surgery, University of Oxford and Oxford Radcliffe Hospitals NHS Trusts,Radcliffe Infirmary, Oxford, UK.
Correspondence to Jane Wolstenholme, PhD, Department of Public Health, University of Oxford, Old Road Campus, Oxford, OX3 7LF UK. [email protected]
© 2007 American Heart Association, Inc.
Stroke is available at http://stroke.ahajournals.org DOI: 10.1161/STROKEAHA.107.482570
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Previously published studies of the costs of aSAH concen-trated on estimating hospital inpatient days using retrospec-tive designs,6–9 and provide reasonable length of stay esti-mates but no information on other resource use items such asstaffing, consumables, complications, readmissions, and re-habilitation. We now report the first detailed comparison oftreatment pathways, resource utilization, and costs associatedwith endovascular coiling and surgical clipping in patientswith ruptured aSAH, using data collected prospectively in theUK during the ISAT multi-country randomized trial.
MethodsResource use data were collected prospectively alongside the Med-ical Research Council International Subarachnoid Aneurysm Trial(ISAT) (ISRCTN49866681), details of which are reportedelsewhere.4,10–11
Before the trial began, all categories of hospital resource use likelyto be important were identified. Trial case record forms (CRFs) werethen designed to record the volume of resources used by each patientin each category, including type and number of hospitalizations andprocedures, procedure duration in minutes, number of coils used inendovascular procedures, and lengths of stay in intensive care and ingeneral wards. Hospital readmissions for further treatment or aftercomplications or adverse events were documented, as was anyfollow up angiography or imaging. Information was also recorded onpatient discharge to rehabilitation. Employment-related informationwas collected and is reported separately from health service costs.Some information was recorded on the domestic circumstances ofpatients, but not on informal care received; these data are excludedfrom this article.
The unit costs used in this analysis are summarized in Table 1;full details are available for downloading at www.herc.ox.ac.uk/downloads.
It was not feasible to collect detailed information for every patienton type and number of staff involved in each procedure, specificequipment, and every consumable item used during the interven-tions. Instead, a detailed observational study was undertaken at theOxford center to identify the main cost drivers for each procedure.Staffing types and numbers, unit cost of coils, and cost per inpatientday were identified as the main cost drivers. A questionnaire wasthen designed, asking all UK centers to provide local information onthe normal numbers and types of staff present for both procedures,mean cost of coils, and cost per inpatient day in an intensive therapyunit (ITU), neurology ward, and neurosurgery ward for that center.Eight of the 22 (36%) centers completed and returned the question-naire; 2 centers subsequently merged, resulting in 7 independentresponses, and these centers represented a cross-section of all the UKbased ISAT centers. No significant differences between centers werefound in reported theater staffing, cost of coils, or cost per inpatientward or ITU day, and so an average was computed across all centers.Unit costs for staff time were obtained from national salary ta-bles,12,13 and equipment costs were provided by the manufacturers.The cost per inpatient day in a district general hospital (DGH) andthe cost per day in a rehabilitation clinic were taken from standardpublications.12
The unit costs of equipment and consumables used by bothprocedures were provided by manufacturers and by the OxfordRadcliffe Hospitals NHS Trust finance department. The equivalentannual cost for equipment was calculated using standard methods atan annual rate of 5%.14
For the endovascular procedure, consumables used were assumedto be the same for all patients, but patient specific data were availableon the use of thrombolytic agent and the number of coils. For theneurosurgical procedure, consumables and the cost of anestheticswere assumed to be the same for all patients and were included as alump sum, but were varied according to whether temporary clipswere used or not. The average cost for anesthetics was calculatedseparately for endovascular and neurosurgical patients and includedwith the cost of consumables.
In summary, for the endovascular procedure, theater costs werecalculated as the product of procedure duration and cost per minuteof staff, equipment costs, the product of number of coils used perpatient and cost per coil, the cost of thrombolytic agent if used, anda cost for all other consumables. The cost per patient for neurosur-gery was calculated as the product of theater time and cost perminute of staff and equipment, plus the cost of consumables. Ifpatients underwent a second procedure, this was costed using thesame methods.
The unit cost of an angiogram was provided by the hospitalfinance department; the cost of a hospital bed day case was includedfor each angiogram. These are shown in Table 1, along with the unitcost of a CT and MRI scan, taken from national sources.15
The total health care cost per patient was calculated by the volumeof health service resources used multiplied by the relevant unit cost.This was then averaged across each trial arm to obtain a mean costper endovascular or neurosurgical patient. Uncertainty around dif-ference in mean cost was handled through nonparametric 95%confidence intervals. Proportions between groups were comparedusing standard �2 test. 98% of the data were complete and thereforeno attempt to impute the remaining 2% was considered. Wecompared baseline characteristics for patients with missing items andthose with complete data and found no differences.
Patients were followed up at 2 months postintervention and on anannual basis thereafter. Long-term follow-up data continue to becollected. In this article we present 12- and 24-month postrandom-ization treatment pathways, resource use, and costs. All analyses areby intention to treat.
Costs are expressed in 2004 £UK with prices inflated to this baseusing the Hospital and Community Health Service Inflation Indexwhere appropriate. All costs incurred over the 12- to 24-monthperiod were discounted at a rate of 3.5%, in line with commonpractice.
Table 1. Summary of Unit Costs Used for the Cost Analysis
Resource Use Category Endovascular Neurosurgery
All staff * £607.38 £620.27
Equipment** £1.29 £0.15
Consumables
Consumables £995 £800
Thrombolytic agent £800 n/a
Coil‡ £440 n/a
Clip n/a £148
Length of stay per day
ITU £1481 £1481
Neurology ward £354 n/a
Neurosurgery ward n/a £364
Rehabilitation Clinic† £229 £229
DGH stroke patients† £227 £227
Imaging and investigations
Angiogram £621 £621
CT scan £104 £104
MRI scan £224 £224
Prices expressed in 2004 pounds sterling. (See detailed information on unitcosts at www.herc.ox.ac.uk/downloads).
*Per hour operating.**Unit cost per minute.‡Based on average costs from 7 centers.†Taken from national sources. (See Netten et al, 2004).
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ResultsA total of 2143 patients were recruited to the ISAT trial by 42neurosurgical centers. In this article we focus on UK patientsonly, comprising 1644 patients, with 809 randomized to theendovascular group and 835 to the neurosurgery group.
Figure 1 shows the flow diagram of resource useconsumption and the missing data items up to 24 monthspostrandomization.
Full information was available on 792 of 809 patients inthe endovascular group (97.9%) and 819 of 835 patients inthe surgery group (98%) at 1 year follow-up. At 2 yearsfollow-up, complete data were available for 786 of 809(97.1%) in the endovascular group and 816 of 835 (97.7%) inthe surgery group. These constitute the final samples used inthe cost analysis. However, we also report resource useresults by specific resource category for all patients for whominformation is available in that category.
From the original 809 randomized to endovascular treat-ment, 791 underwent the allocated treatment with 10 cross-overs to surgery. Of the remaining 8, 7 died before theprocedure and 1 never had a procedure (Figure 1). From theoriginal 835 randomized to surgery, 776 had the allocatedtreatment and 32 crossed-over to coiling. Of the remaining27, 19 died before receiving any treatment and 8 never had aprocedure.
Resource Use Associated With the First Episodeof CareTable 2 shows the resource use associated with the firstepisode of care, over the first 12 months of follow-up.
Mean resource use (SD) averaged over the number ofpatients using the resource category is reported. The meantime spent in the angiogram suite for the first endovascularintervention was estimated to be 137 (56) minutes with anaverage of 3.8 (2.5) coils per intervention. The averageduration in the angiogram suite among crossover patients wascalculated as 140 (51) minutes with a mean number of 5.1(2.5) coils inserted.
The mean (SD) theater duration of those receiving surgeryas first treatment was estimated to be 214 (77) minutes with213 patients receiving temporary clips. Mean theater durationfor cross-overs was estimated to be 207 (78) minutes with 3patients receiving temporary clips.
Resource Use Associated With SubsequentProcedures, Complications, Adverse Events,and Follow-Up AngiogramsTable 3 presents the number of patients and resource utiliza-tion for patients requiring subsequent procedures orfollow-up angiograms or after an adverse event or complica-tion, for the period from postoriginal discharge up to 1-yearfollow-up.
1644 randomised
809 allocated endovascular treatment
835 allocated neurosurgery treatment
7 died before first procedure 1 never had a procedure
791 had first endovascular treatment 10 had first neurosurgery
19 died before first procedure 8 never had a procedure
776 had first neurosurgery 32 had first endovascular treatment
6 missing duration resource use item 1 missing number of coils
6 missing duration resource use item
784 had complete endovascular treatment data 10 had complete neurosurgery data
771 had complete neurosurgery data 31 had complete endovascular treatment data
12 had at least one additional endovascular treatment before original discharge 54 had at least one additional neurosurgery treatment before original discharge
4 had at least one additional neurosurgery treatment before original discharge 19 had at least one additional endovascular treatment before original discharge
26 died during or after original procedure
41 died during or after original procedure
1 missing duration resource use item
39 had at least oneadditional endovascular treatment related to the same aneurysm after original discharge 25 had at least one additional endovascular treatment non-related to the same aneurysm after original discharge
15 had at least one additional neurosurgery treatment related to the same aneurysm after original discharge 12 had at least one additional neurosurgery treatment non-related to the same aneurysm after original discharge
3 missing time in theatre 1 missing number of coils 1 missing whether thrombolytic agent was used
13 had at least oneadditional endovascular treatment related to the same aneurysm after original discharge 6 had at least one additional endovascular treatment non-related to the same aneurysm after original discharged
2 had at least oneadditional neurosurgery treatment related to the same aneurysm after original discharge 3 had at least one additional neurosurgery treatment non-related to the same aneurysm after original discharge
1 missing time in theatre 1 missing number of coils 1 missing whether thrombolytic agent was used
2 missing time in theatre 1 missing whether temporary clips were used
Other missing data items: 2 patients missing in length of stay rehabilitation clinic first episode of care 3 patients had missing length of stay at ward for readmissions 3 patients had missing length of stay for checked angiograms
Other missing data items: 2 patients missing in length of stay district general hospital first episode of care 2 patients missing in length of stay rehabilitation clinic first episode of care 4 patients had missing length of stay at ward for readmissions 1 patient had missing length of stay for checked angiograms
786 patients with complete resource use data at 24 months follow-up
816 patients with complete resource use data at 24 months follow-up
Figure 1. Consort flow diagram for resource use consumption at 24 months follow-up.
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Employment-Related Resource UseOccupational status before aSAH could not be collected forpatients who were dead at 1 year follow-up (139 patients).Seventeen patients in the endovascular group and 22 in theneurosurgery group who were known to be alive at 12months follow-up had some items of missing employmentinformation. At 24 months follow-up these figure in-creased to 63 patients in the endovascular group and 84 inthe neurosurgery group with some items of missing em-ployment information.
Some patients who returned to work after aSAH had tostop within the 24-month period because of health reasons,whereas others returned to work with modified hours. Tocapture any possible variation in work status we calculated
the number of days in paid employment since randomizationfor the patient. For those patients in full-time employment, itwas assumed that the total number of days at work was 22days per month (52 weeks divided by 12 months). Forpatients in less than full-time employment, we made theassumption that this equated to 11 days per month.
Figure 2 shows the proportion of patients who had returnedon any particular day during the 24-month postrandomizationperiod. It also presents �2 results testing for differences at 12and 24 months follow-up. The number of patients returning towork was significantly higher in the endovascular groupcompared with the neurosurgery group at 12 months follow-up, �2�6.29, P�0.012. The difference was no longer signif-icant at 24 months follow-up.
Table 2. Resource-Use Associated With the First Episode of Care; First 12 Months Follow-Up
Endovascular (n�809) Neurosurgery (n�835)
Resource CategoryNo. of Patients UsingResource Category
Mean Resource Useper Patient (SD) Min Max
No. of Patients UsingResource Category
Mean Resource Useper Patient (SD) Min Max
Endovascular intervention(1st episode of care)
Duration (in minutes) 785 137.41 (55.69) 45 420 31 140.07 (50.51) 60 300
No. of coils 790 3.76 (2.49) 0 26 32 5.06 (2.54) 2 10
Thrombolytic agent used 18 0
Neurosurgery intervention(1st episode of care)
Duration (in minutes) 10 207 (77.75) 120 360 771 213.81 (76.94) 60 595
Temporary clips used 3 213
Subsequent interventionprocedures before originaldischarge
No. of endovascular procedures
1 additional 12 18
2 additional 0 1
Duration (in minutes) 12 154.67 (37.99) 105 240 19 152.11 (52.48) 60 255
No. of coils 12 2.58 (1.17) 0 4 19 3.53 (2.43) 0 8
Thrombolytic agent used 1 2
No. of neurosurgical procedures
1 additional 53 2
2 additional 1 1
3 additional 0 1
Duration (in minutes) 54 229.67 (73.54) 60 390 3 190 (105.36) 90 300
Temporary clips used 19 1
Imaging and investigationspost-randomisation
No. of angiograms 789 1.16 (0.41) 1 3 806 1.14 (0.37) 1 3
No. of CT scans 735 1.78 (1.56) 1 8 773 2.02 (1.28) 1 9
No. of MRI 43 1.16 (0.48) 1 3 25 1.24 (0.44) 1 2
Length of stay first episodeof care
No. of ITU days 301 5.25 (5.91) 1 40 349 5.77 (5.94) 1 37
No. of ward days 808* 14.82 (11.92) 1 152 834* 17.25 (15.31) 1 316
No. of DGH days 332 25.28 (42.93) 1 365 409 29.71 (51.97) 1 389
No. of rehabilitation clinic days 52 73.39 (101.73) 2 650 71 115.28 (132.32) 2 666
*2 patients spent all the time at ITU until they died.
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Table 3. Resource Use Associated With Subsequent Procedures and Follow-Up Angiograms (12 Months Follow-Up)
Endovascular (n�809) Neurosurgery (n�835)
Resource CategoryNo. of Patients UsingResource Category
Mean Resource Useper Patient (SD) Min Max
No. of Patients UsingResource Category
Mean Resource Useper Patient (SD) Min Max
Subsequent endovascularprocedures following originaldischarge
No. of endovascular procedures
Related to the original vessel ID 30 10
Not related to the original vessel ID 18 6
Duration (in minutes)
Related to the original vessel ID 28 141.68 (48.21) 80 240 9 149.44 (44.61) 90 210
Not related to the original vessel ID 17 99.41 (26.21) 60 150 5 124 (53.78) 75 210
No. of coils
Related to the original vessel ID 29 3.41 (3.06) 0 14 10 4.1 (4.28) 0 11
Not related to the original vessel ID 18 1.78 (1.70) 0 5 5 2.85 (1.48) 1 5
Thrombolytic agent used (% Yes)
Related to the original vessel ID 3 0
Not related to the original vessel ID 0 0
Subsequent neurosurgicalprocedures following originaldischarge
No. of neurosurgical procedures
Related to the original vessel ID 12 2
Not related to the original vessel ID 9 2
Duration (in minutes)
Related to the original vessel ID 11 171.36 (57.67) 100 270 2 270 (169.71) 150 390
Not related to the original vessel ID 8 165 (84.47) 90 300 1 240 240 240
Temporary clips used (%Yes)
Related to the original vessel ID 1 1
Not related to the original vessel ID 1 1
Length of stay subsequentprocedures following originaldischarge
Subsequent endovascularprocedures
No. of days ITU
Related to the original vessel ID 4 4.75 (3.86) 1 9 2 2 1 1
Not related to the original vessel ID 4 1.5 (0.58) 1 2 1 1 1 1
No. of days ward
Related to the original vessel ID 29 5.45 (4.71) 2 27 8 8.5 (8.12) 2 27
Not related to the original vessel ID 17 6.77 (11.97) 1 52 5 4.2 (2.17) 3 8
Subsequent neurosurgicalprocedures
No. of days in ITU
Related to the original vessel ID 5 4.8 (5.02) 1 13 1 4 4 4
Not related to the original vessel ID 1 1 1 1 1 1 1 1
No. of ward days
Related to the original vessel ID 12 8.08 (3.75) 5 19 1 11 11 11
Not related to the original vessel ID 9 6.55 (2.92) 4 14 1 9 9 9
(Continued )
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The mean (SD) number of days in paid employment sincerandomization was estimated to be 59(84) days in theendovascular group and 43(73) days in the neurosurgerygroup, a significant difference of 16 days (10 to 25, P�0.01)within the first year. At 24 months follow-up these figurewere 148 (195) days in the endovascular group and 119 (180)in the neurosurgery group, a significant difference of 29 days(10 to 47, P�0.01) favoring the endovascular group.
Similar, but greater differences were found in the subgroupof patients who were in paid employment before the aSAH: at12 months follow-up the difference was 24 days (13 to 35,P�0.01) whereas at 24 months follow-up the difference wasestimated to be 39 days (13 to 35, P�0.01).
CostsTable 4 reports details of the costs associated with the firstepisode of care and subsequent care up to 12 monthsfollow-up. Staff costs associated with interventions in thefirst episode of care were significantly lower in theendovascular group (£1450 per patient) than in the neuro-surgical group (£2108 per patient), a difference of £658(�£730, �£588) in favor of the endovascular group. As
Table 1 showed, the cost per hour of staff input in theaterwas almost identical for the 2 procedures, and hence thedifference in total staff costs is mainly attributable toshorter operating times rather than different types ornumbers of staff present.
However, consumable costs were significantly higher inthe endovascular group (£2627) than in the neurosurgicalgroup (£901), a difference of £1726 (£1637, £1819). Thisdifference was primarily attributable to the cost of coils.
The cost of hospital stay after operative procedures in thefirst episode of care was significantly lower in the endovas-cular group (£11 547) than in the neurosurgical group(£15 311), a difference of £3764 (�£5482, �£2099), reflect-ing the fact that the neurosurgical group spent more days ininpatient wards, ITU, and rehabilitation clinics comparedwith the endovascular patients.
After the first episode of care, the endovascular group in-curred significantly higher costs related to additional proceduresand check angiograms, but there was no significant differencebetween groups in the costs of complications and adverse events.
The mean (SD) overall total cost per patient at 12 monthsfollow-up was estimated to be £18 436 (£15 849) and
Table 3. Continued
Endovascular (n�809) Neurosurgery (n�835)
Resource CategoryNo. of Patients UsingResource Category
Mean Resource Useper Patient (SD) Min Max
No. of Patients UsingResource Category
Mean Resource Useper Patient (SD) Min Max
Length of stay for complications andadverse events following original discharge
No. of ward days 107 11.37 (26.06) 1 226 104 13.26 (31.75) 1 261
Follow-up check angiograms
No. of patients having check angiograms
1 check angiogram 460 145
2 check angiograms 64 16
3 check angiograms 6 2
IN EMPLOYMENT AT 12M:256/704 (36.36%) endovascular212/705 (30.07%) neurosurgery
Chi-square = 6.29 p<0.012
IN EMPLOYMENT AT 24M:266/656 (40.55%) endovascular227/635 (35.75%) neurosurgery
Chi-square = 3.15 p<0.076
0.00
0.25
0.50
0.75
1.00
Pro
port
ion
of p
atie
nts
in e
mpl
oym
ent
0 200 400 600 800
Time elapsed since randomisation (in days)
EndovascularNeurosurgery
Figure 2. Number of patients returningto paid employment up to 24 monthsfollow-up.
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Table 4. Cost Results Associated With Resource-Use Consumption (12-Months Follow-Up)
Cost CategoryEndovascular (n�792)
Mean Cost per Patient (SD)Neurosurgery (n�819)
Mean Cost per Patient (SD)Mean Cost Difference
(Nonparametric 95% CI)
Intervention (first episode of care) (a)
Staff endovascular first treatment
Radiologist consultant £504 (£221) £20 (£105)
Radiologist registrar £94 (£41) £4 (£20)
Anaesthetist consultant £504 (£221) £20 (£105)
Radiographer £131 (£57) £5 (£27)
Nurses endovascular procedure £189 (£83) £7 (£40)
Staff surgery first treatment
Surgeon consultant £10 (£92) £747 (£346)
Surgeon registrar £2 (£17) £139 (£65)
Anaesthetist consultant £10 (£92) £747 (£346)
Anaesthetist registrar £2 (£17) £139 (£65)
Nurses surgical procedure £4 (£35) £280 (£130)
Total cost staff first treatment £1450 (£612) £2108 (£878) �£658 (�£730 to �£588)*
Equipment endovascular first treatment £182 (£80) £7 (£38)
Equipment surgery first treatment £1 (£3) £28 (£13)
Total cost equipment first treatment £183 (£79) £35 (£35) £148 (£142 to £154)*
Consumables first treatment
Coils £1626 (£1107) £82 (£472)
Thrombolytic agent £18 (£119) £0 (£0)
Other endovascular consumables £972 (£148 £37 (£187)
Other surgical consumables £11 (£95) £782 (£223)
Total cost consumables first treatment £2627(£1134) £901 (£529) £1726 (£1637 to £1819)*
Total cost further procedures before discharged £260 (£938) £102 (£700)
Total cost intervention first episode of care (a) £4520 (£1491) £3146 (£1296) £1374 (£1230 to £1499)*
Total cost imaging and investigations (b) £886 (£324) £882 (£300)
Length of stay first episode of care (c)
No. of ITU days £2872 (£6422) £3573 (£7102)
No. of ward days £5215 (£4234) £6103 (£5454)
No. of DGH days £2371 (£6883) £3346 (£8993)
No. of rehabilitation clinic days £1089 (£7225) £2289 (£11568)
Total cost length of stay first episode of care (c) £11547 (£14588) £15311 (£20518) �£3764 (�£5482 to �£2099)*
Total costs first episode of care (a�b�c) £16953 (£14949) £19339 (£20708) �£2386 (�£4170 to �£638)*
Intervention further procedures (d)
Endovascular procedures
Related to the original vessel ID £142 (£868) £39 (£487)
Not related to the original vessel ID £63 (£458) £23 (£295)
Surgery procedures
Related to the original vessel ID £36 (£313) £6 (£176)
Not related to the original vessel ID £26 (£269) £4 (£116)
Total cost intervention further procedures (d) £267 (£1081) £72 (£604) £195 (£114 to £285)*
Length of stay further procedures (e)
Endovascular procedures
No. of days ITU readmissions
Related to the original vessel ID £36 (£611) £4 (£73)
(Continued )
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£20 176 (£21 984) in the endovascular and neurosurgerygroups respectively, a nonsignificant difference of �£1740(�£3582, £32) in favor of the endovascular patients.
Supplemental Tables I and II (available online at http://stroke.ahajournals.org) summarize the resource use and costsof subsequent care incurred from 12 to 24 months follow-up.The mean (SD) total follow-up costs from 12 to 24 monthswere estimated to be £613 (£4727) in the endovascular groupand £131 (£895) in the surgery arm, a significant differenceof £482 (£221, £888) in favor of the surgical group.
DiscussionIncreasing importance is attached to accurately identifyingtreatment pathways, resource utilization, and costs of healthcare interventions in all countries. Simplistic approacheswhich only look at narrow aspects of this, such as includingonly inpatient stays and omitting other important resource usecategories such as subsequent procedures, readmissions, re-habilitation, and days lost from work, can result in incorrectpolicy decisions being made. Moreover, accurate detailedestimates of resource use and costs are necessary precursorsto the calculation of cost-effectiveness of interventions, inthis case, treatments for aSAH.
This article provides the first detailed estimates of patienttreatment pathways, resource use, and costs up to 24 monthspostrandomization for the endovascular and neurosurgicaltreatment of ruptured aSAH. We found a nonsignificantdifference (�£1740, �£3582 to £32) in the total 12-monthcost of treatment for aSAH in favor of endovascular treat-ment. Endovascular patients had higher costs related to theintervention for both the first and any subsequent procedures,but this was more than offset by lower costs related to length
of stay for the first procedure and fewer costs associated withcomplications and adverse events. In the following 12- to24-month period, the costs related to subsequent procedures,angiograms, complications, and adverse events were greaterfor the endovascular group of patients, reducing the differ-ence in total per patient cost to �£1228 (�£3199 to £786) forthe period up to 24 months follow-up.
Our findings are in line with but significantly extend thosesuggested by 2 previous articles16,17 reporting on limitedresource use and cost information for very small patientsubsamples from single centers of the ISAT study in Austra-lia (n�22) and Canada (n�62). Both suggested that thehigher costs of the endovascular compared with neurosurgicalpropcedure were counter-balanced by savings from reducedlength of stay.
As well as providing information on the hospital costs ofendovascular and neurosurgical treatment for aSAH, thisarticle reports employment status of patients after the aSAHand its treatment. This is important as the average age ofpatients in the ISAT study was 51.7 years. Our results showthat at 12 months postrandomization a significantly largerproportion of patients in the endovascular group had returnedto work compared with patients in the neurosurgical group;this significant difference no longer held at 24 months. Theendovascular patients on average worked 16 days more thanthe neurosurgery patients over the first year, with a continu-ing significant difference of 29 days in paid employment overthe 2 years postrandomization.
Unfortunately the study did not permit collection of infor-mation on use of long-term nursing and informal care, andour cost results omit these potentially considerable costs.
Accurate costing is extremely pertinent to the financing ofhospital care, notably in England where the recent transition
Table 4. Continued
Cost CategoryEndovascular (n�792)
Mean Cost per Patient (SD)Neurosurgery (n�819)
Mean Cost per Patient (SD)Mean Cost Difference
(Nonparametric 95% CI)
Not related to the original vessel ID £11 (£166) £2 (£52)
No. of days ward readmissions
Related to the original vessel ID £66 (£486) £27 (£394)
Not related to the original vessel ID £50 (£696) £9 (£128)
Surgery procedures
No. of days ITU readmissions
Related to the original vessel ID £45 (£772) £7 (£207)
Not related to the original vessel ID £2 (£53) £2 (£52)
No. of ward day readmissions
Related to the original vessel ID £41 (£378) £5 (£136)
Not related to the original vessel ID £24 (£256) £4 (£111)
Total cost length of stay furtherprocedures (e)
£275 (£1729) £60 (£587) £215 (£89 to £340)*
Total cost follow-up check angiograms (f) £409 (£325) £121 (£250) £288 (£259 to £317)*
Total cost complications and adverseevents (g)
£532 (£3643) £584 (£4284) �£52 (�£466 to £314)
Total follow-up costs (d�e�f�g) £1483 (£4530) £837 (£4479) £646 (£232 to £1058)*
Total cost per patient 12 monthsfollow-up (a�b�c�d�e�f�g)
£18436 (£15849) £20176 (£21984) �£1740 (�£3582 to £32)
*P�0.05
118 Stroke January 2008
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to “payment by results” anticipates that primary care trustswill commission services using a standard national pricetariff, adjusted for regional variation in wages and other costsof service delivery. Inaccurate tariffs will lead to incorrectreimbursement, inappropriate incentives, and overall ineffi-ciencies in resource allocation. The detailed cost resultsreported in this article, therefore, provide useful informationfrom which national tariffs could be calculated.18
ConclusionNo significant difference in costs between the endovascularand neurosurgery groups existed at 12 months follow up. Thehigher initial and subsequent procedure costs for endovascu-lar treatment were more than offset by lower costs related toinitial procedure inpatient stay and fewer complications. Inthe following 12- to 24-month period, costs for subsequentprocedures, angiograms, complications, and adverse eventswere greater for the endovascular patients, reducing thedifference in total per patient cost over the 24-month period.
AcknowledgmentsOur thanks go to the staff of the Diabetes Trials Unit, University ofOxford, for the data input and management; the staff of the ClinicalTrial Service Unit, University of Oxford, for their invaluable helpand advice, and for providing the randomization service. We wouldespecially like to acknowledge the support of all the patients andtheir relatives who agreed to participate in the study and all themedical, radiological, radiographic, and nursing staff in the manyparticipating centers (listed in Molyneux et al 2002) who havesupported the trial, especially those who are not noted by name. Thestrength of the ISAT findings results from their willingness to takepart and to continue to provide follow-up data.
Sources of FundingThe pilot phase of the study was supported by a grant from OxfordRegional Health Authority Research and Development (1994 to 97).The main trial (1997 to date) is supported by grants from: TheMedical Research Council, UK; Programme Hospitalier de Recher-che Clinique 1998 of the French Ministry of Health (AOM 98150)sponsored by Assistance Publique-Hopitaux de Paris (AP-HP); theCanadian Institutes of Health Research; and the Stroke Associationof the UK (for the neuropsychological assessments).
DisclosuresA.J.M. has a consulting and advisory agreement with Micrus, Inc, amanufacturer of detachable platinum coils, with stock interest in thecompany. R.S.C.K. and A.J.M. have received support for travel tomeetings from Boston Scientific.
References1. Linn FHH, Rinkel GJE, Algra A, vanGijn J. Incidence of subarachnoid
hemorrhage - role of region, year, and rate of computed tomography: Ameta-analysis. Stroke. 1996;27:625–629.
2. Wermer MJH, van der Schaaf IC, Velthuis BK, Algra A, Buskens E,Rinkel GJE. Follow-up screening after subarachnoid haemorrhage: Fre-quency and determinants of new aneurysms and enlargement of existinganeurysms. Brain. 2005;128:2421–2429.
3. Alvord EC, Loeser JD, Bailey WL, Copass MK. Subarachnoid hemor-rhage due to ruptured aneurysms. A simple method of estimatingprognosis. Arch Neurol. 1972;27:273–284.
4. Molyneux A, Kerr R, Stratton I, Sandercock P, Clarke M, ShrimptonJ. International subarachnoid aneurysm trial (ISAT) of neurosurgicalclipping versus endovascular coiling in 2143 patients with ruptured intra-cranial aneurysms: A randomised trial. Lancet. 2002;360:1267–1274.
5. Molyneux AJ, Kerr RSC, Yu LM, Clarke M, Sneade M, Yarnold JA.International subarachnoid aneurysm trial (ISAT) of neurosurgicalclipping versus endovascular coiling in 2143 patients with ruptured intra-cranial aneurysms: A randomised comparison of effects on survival,dependency, seizures, rebleeding, subgroups, and aneurysm occlusion.Lancet. 2005;366:809–817.
6. Holloway RG, Witter DM, Lawton KB, Lipscomb J, Samsa G. Inpatientcosts of specific cerebrovascular events at five academic medical centers.Neurology. 1996;46:854–860.
7. Reed SD, Blough DK, Meyer K, Jarvik JG. Inpatient costs, length ofstay, and mortality for cerebrovascular events in community hospitals.Neurology. 2001;57:305–314.
8. Taylor CL, Yuan Z, Selman WR, Ratcheson RA, Rimm AA. Mortalityrates, hospital length of stay, and the cost of treating subarachnoidhemorrhage in older patients: Institutional and geographical differences.J Neurosurg. 1997;86:583–588.
9. Yundt KD, Dacey RG, Diringer MN. Hospital resource utilization in thetreatment of cerebral aneurysms. J Neurosurg. 1996;85:403–409.
10. International Subarachnoid Aneurysm Trial (ISAT) website. Trialprotocol available at: Http://www.Surgery.Ox.Ac.Uk/nvru/isat.
11. Molyneux A, Kerr R. Protocol 99prt18 international subarachnoid aneu-rysm trial (ISAT). 2006.
12. Netten A, Dennett J, Knight J. Unit costs of health and social care 2004.PSSRU; 2004.
13. Department of Health. Advanced letter. Nurses’ and midwives pay. 2005.14. Drummond MF, O’Brien B, Stoddart GL, Torrance GW. Methods for the
Economic Evaluation of Health Care Programmes. Oxford: Oxford Uni-versity Press; 1997.
15. Department of Health. Nhs reference costs: Data publications. 2004.16. Bairstow P, Dodgson A, Linto J, Khangure M. Comparison of cost and
outcome of endovascular and neurosurgical procedures in thetreatment of ruptured intracranial aneurysms. Australasian Radiol.2002;46:249 –251.
17. Javadpour M, Jain H, Wallace MC, Willinsky RA, ter Brugge KG,Tymianski M. Analysis of cost related to clinical and angiographic outcomesof aneurysm patients enrolled in the international subarachnoid aneurysmtrial in a north american setting. Neurosurgery. 2005;56:886–893.
18. Department of Health. Payment by results available at: Http://www.Dh.Gov.Uk/policyandguidance/organisationpolicy/financeandplanning/nhsfinancialreforms/fs/en.;2006.
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