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Cost-effectiveness of intraspinal drug delivery for chronic pain
Seminars in Pain Medicine Vol. 2 No. 1 2004
Cost-Effectiveness of Intraspinal Drug Delivery for Chronic Pain HOLLIE NGUYEN and SAMUEL J. HASSENBUSCH, MD, PhD
ABSTRACT Economic considerations for intrathecal morphine pump versus alternative therapy (medical management) in chronic and cancer pain can be assessed with different economic models such as cost-minimization, cost-effectiveness, and cost– benefit analyses. The objective of each model is to estimate the direct cost of an intrathecal morphine pump as compared with other systemic treatments. The purpose of this study is to determine cost factors for various routes of delivery, particularly with regard to hospital stay, charges relating to the operation, staff salaries, postoperative care including pump replacement, routine hospital check-ups, and other possible complications that require medical care. Key words: intrathecal morphine pump, chronic pain, failed back surgery syndrome, cost-effectiveness, cost-minimization, cost– benefit analysis.
For patients suffering from chronic pain, such as failed back surgery syndrome or cancer pain, treatment options can be greatly influenced by the rising medical costs. Economic models allow for both physicians and patients to assess the advantages and disadvantages of each treatment with regard to effectiveness and costs. Cost-effectiveness analysis examines patient’s satisfaction versus the cost of achieving that satisfaction. The basic question for this type of assessment is: For the amount of money spent, what is the utility to the patient in an overall sense? The cost-effectiveness model compares the costs of different methods for achieving a particular outcome. For example, for tumor shrinkage, the costs of different treatments, such as radiation, surgery, and chemotherapy, would be compared. The objective of cost-effectiveness models
is to evaluate the costs and charges of each method for obtaining the desired outcome. Cost– benefit analysis considers society as a whole with regard the government and Medicare. Examples of questions in this type of analysis include: What is the bottom line for society? What are the costs/ benefits to society in terms of dollars? For a patient with cancer, what would be the costs of different treatments to get that individual back to work? The goal is to get the patient well and able to return to work to generate taxes for the government and for increasing productivity as a whole. The purpose of this study is to apply these economic models in three subsequent studies (the Bedder et al study, the MD Anderson predictive model, and failed back pain studies) in patients with chronic noncancer pain.
The Bedder et al Study From the Department of Neurosurgery, University of Texas MD Anderson Cancer Center, Houston, TX. Address reprint requests to Samuel J. Hassenbusch, MD, PhD, University of Texas MD Anderson Cancer Center, 1515 Holcombe Boulevard, Unit #442 (Neurosurgery), Houston, TX 77030. E-mail: [email protected] © 2004 Elsevier Inc. All rights reserved. 1537-5897/04/0201-0007/$30.00/0 doi:10.1016/j.spmd.2004.01.002
In 1991, Bedder et al conducted a study comparing the costs and effectiveness of an external catheter versus an implanted pump.1 A Du Pen epidural catheter was placed in 5 cancer patients with a life expectancy of 2.5 months. The SynchroMed pump was implanted in 15 patients, 7 of whom had cancer pain
43
44 Seminars in Pain Medicine Vol. 2 No. 1 March 2004 Table 1. Cost Comparisons: External Catheter Versus Implanted Pump
Initial cost Monthly follow-up costs Monthly costs Pump rental Drug Drug (cassette) Professional fee Dispensing fee Dressing supplies Nursing visits Total monthly costs
Exterior catheter
Implanted pump
$9164 $2148
$15,356 $273
$450 $23 $570 $250 $836 $212 $80 $2148
$273
The Bedder et al study suggests that, although the implanted pump is costly in the beginning ($15,356), monthly charges decline to $273. In contrast, the initial cost of the external catheter is lower at $9164, whereas monthly maintenance costs are higher at $2148. (Source: Hassenbusch, SJ: Cost modeling for alternate routes of administration of opioids for cancer Pains. Oncology 13:64, 1999. Used by permission.)
and 8 noncancer pain. The costs of an external catheter included pump rental fee, drug fee (cassette preparations and dispensing fees), supplies, and hospital visits. The implanted pump included costs of the drug, the pump itself, and the operation. The results concluded that the initial cost for a pump was about $15,000, whereas the initial cost for an external catheter was $9000 (Table 1). However, the $9000 amount could be drastically lowered depending on the method of catheter placement and length of hospital stay. Another issue was monthly follow-up costs, which were found to be $2000/ month for the catheter versus $273/month for the implantable pump. Cost efficacy of the pump was noted when patients survived beyond the break-even point, demonstrating cost minimization.
A Theoretical Model From a theoretical perspective, the MD Anderson model was based on the actual charges for various items and their predicted costs for such treatments. The five parameters included: (a) initial charges of screening and delivery of opioids; (b) drug charges for follow up visits; (c) service charges for ongoing check-ups; (d) medical personnel fee; and (e) readmission and/or complications charges. The relative contributions of cost components are illustrated in Fig 1 for oral morphine, transdermal fentanyl, subcutaneous or intravenous morphine delivery, epidural external pump, and intrathecal implanted pump. At 1 month, drug charges accounted for 50% of the cost of oral morphine. Other expenses included home care, whereas clinic and readmission costs for complications were insignificant. Transdermal fentanyl resulted in the same cost breakdown as oral morphine administration. Use of subcutaneous (intravenous) morphine delivery and epidural external pump resulted in lower drug costs, whereas home-care charges increased. According to the Bedder et al study discussed earlier, the charges for an externalized system remain reasonable in the beginning, whereas the high cost of an implanted pump was from the cost of the pump itself with smaller charges for drugs, clinic and home care, and readmission. The study concluded that the more expensive options are either intravenous delivery of morphine or an externalized catheter system. Despite the relative economics of epidural delivery in the beginning, home care, drug charges, the cassette, and pump rentals become increasingly expensive over time due to dose escalation. The model predicts that, over a period of 15 months, an external system may result
Fig 1. Relative contributions of the different cost components for each delivery route. Relative contributions are presented for oral morphine, transdermal fentanyl, subcutaneous or intravenous morphine delivery, the epidural external pump, and the intrathecal implanted pump. (Source: Hassenbusch SJ: Cost modeling for alternate routes of administration of opioids for cancer pains. Oncology 13:64, 1999. Used by permission.)
Cost-Effectiveness of Intraspinal Drug Delivery
in $100,000 to $120,000 in total costs. In contrast, the intrathecal pump has a high initial cost of $15,000 to $20,000 for the pump and the operation to have it implanted. In addition to these high costs, one must also note the possible complications with pump failure or readjustments that might require the patient to be readmitted to the hospital. However, subsequent charges for home care and drug costs are miniscule. In a noncancer setting, the best option would be an implantable pump because it allows for large doses of morphine over a significant amount of time with fewer costs for maintenance. Back Pain Syndrome Studies in a Noncancer Setting In a cost-effective study of intrathecal infusion for chronic back pain, a comparison was made between intrathecal drug therapy versus conventional therapy.2 There were 67 patients with failed back syndrome, 23 of whom had an implantable pump, and 44 served as controls receiving the conventional pain treatment. These patients were observed for a period of 5 years during which the costs were tabulated for diagnostic imaging, professional fees, hardware, nursing visits for pump maintenance, alternative therapies, and hospitalization costs. Patients from both groups responded to the Oswestry Pain Questionnnaire to assess their pain and quality of life posttreatment. The calculated cost for an intrathecal drug pump was $29,410, versus $38,000 for conventional treatment. The initial cost of the pump was high; however, after 28 months, the costs for conventional drug therapy became more expensive. Further indications by the Oswestry Pain Index reported a 27% improvement in patients who underwent pump therapy, with 12% improvement in the control group. The study concluded by indicating that intrathecal drug therapy is cost-effective in the long run despite the high initial costs of the implantable devices. A crucial point is that the study provided no reference to the potential side-effects and possible postoperative complications of intrathecal drug therapy that would require hospitalization. In a study by de Lissovoy et al3 the main objective was to observe the direct cost of intrathecal delivery of morphine versus conventional pain management over a period of 60 months.1 The cost-effectiveness of the pump was calculated based on 65% to 81%
●
Nguyen and Hassenbusch
45
“adequate” to excellent pain relief compared with conventional management. The predicted baseline value (most likely) of pump implantation over 60 months was $82,893 (averaging $1382/month). The calculated best-case scenario (minimal adverse event, low costs) was $53,468 ($891/month), and the estimated worst-case scenario (high adverse event, high costs) was $125,102 ($2085/month). Moreover, the study concluded that for back pain there is an “intersection” at 20 months, which means that, for patients with chronic back pain, it would be cheaper and more effective to have an implanted pump than systemic treatment. It is important to note that drugs are not the primary costs, but rather charges resulting from doctor visits, physical therapy, emergency room visits, and readmissions. The objective here is to minimize the costs of supplemental therapy with maximum pain relief. Assessment of charges for each method of opioid delivery can be estimated using models based on actual vendor quotations, such as in the Bedder et al study, or by using standard charges to create a computer model of predicted costs, such as in the MD Anderson model. There were some important conclusions established by all three models (Bedder et al study, MD Anderson predictive model, and back pain studies). First, there is an apparent break-even point between 3 and 6 months when it becomes more economical to have an implanted system than an external catheter. In a noncancer setting, the break-even point of an implanted pump versus systemic treatment is 1.5 to 2.5 years. One critical note is that these studies did not suggest patients be treated by the most inexpensive approach, but rather sought to analyze charges associated with the different treatments.
References 1. Bedder MD, Burchiel K, Larson A: Cost analysis of two implantable narcotic delivery systems. J Sympt Manag 6:368-373, 1991 2. Kumar K, Hunter G, Demeria DD: Treatment of chronic pain by using intrathecal drug therapy compared with conventional pain therapies: A cost-effective analysis. Neurosurgery 97:803-810, 2002 3. de Lissovoy G, Brown RE, Halpern M, et al: Costeffectiveness of long term intrathecal morphine therapy for pain associated with failed back surgery syndrome. Clin Ther 19:96-112, 1997
Cost-Effectiveness of Intraspinal Drug Delivery for Chronic Pain HOLLIE NGUYEN and SAMUEL J. HASSENBUSCH, MD, PhD
ABSTRACT Economic considerations for intrathecal morphine pump versus alternative therapy (medical management) in chronic and cancer pain can be assessed with different economic models such as cost-minimization, cost-effectiveness, and cost– benefit analyses. The objective of each model is to estimate the direct cost of an intrathecal morphine pump as compared with other systemic treatments. The purpose of this study is to determine cost factors for various routes of delivery, particularly with regard to hospital stay, charges relating to the operation, staff salaries, postoperative care including pump replacement, routine hospital check-ups, and other possible complications that require medical care. Key words: intrathecal morphine pump, chronic pain, failed back surgery syndrome, cost-effectiveness, cost-minimization, cost– benefit analysis.
For patients suffering from chronic pain, such as failed back surgery syndrome or cancer pain, treatment options can be greatly influenced by the rising medical costs. Economic models allow for both physicians and patients to assess the advantages and disadvantages of each treatment with regard to effectiveness and costs. Cost-effectiveness analysis examines patient’s satisfaction versus the cost of achieving that satisfaction. The basic question for this type of assessment is: For the amount of money spent, what is the utility to the patient in an overall sense? The cost-effectiveness model compares the costs of different methods for achieving a particular outcome. For example, for tumor shrinkage, the costs of different treatments, such as radiation, surgery, and chemotherapy, would be compared. The objective of cost-effectiveness models
is to evaluate the costs and charges of each method for obtaining the desired outcome. Cost– benefit analysis considers society as a whole with regard the government and Medicare. Examples of questions in this type of analysis include: What is the bottom line for society? What are the costs/ benefits to society in terms of dollars? For a patient with cancer, what would be the costs of different treatments to get that individual back to work? The goal is to get the patient well and able to return to work to generate taxes for the government and for increasing productivity as a whole. The purpose of this study is to apply these economic models in three subsequent studies (the Bedder et al study, the MD Anderson predictive model, and failed back pain studies) in patients with chronic noncancer pain.
The Bedder et al Study From the Department of Neurosurgery, University of Texas MD Anderson Cancer Center, Houston, TX. Address reprint requests to Samuel J. Hassenbusch, MD, PhD, University of Texas MD Anderson Cancer Center, 1515 Holcombe Boulevard, Unit #442 (Neurosurgery), Houston, TX 77030. E-mail: [email protected] © 2004 Elsevier Inc. All rights reserved. 1537-5897/04/0201-0007/$30.00/0 doi:10.1016/j.spmd.2004.01.002
In 1991, Bedder et al conducted a study comparing the costs and effectiveness of an external catheter versus an implanted pump.1 A Du Pen epidural catheter was placed in 5 cancer patients with a life expectancy of 2.5 months. The SynchroMed pump was implanted in 15 patients, 7 of whom had cancer pain
43
44 Seminars in Pain Medicine Vol. 2 No. 1 March 2004 Table 1. Cost Comparisons: External Catheter Versus Implanted Pump
Initial cost Monthly follow-up costs Monthly costs Pump rental Drug Drug (cassette) Professional fee Dispensing fee Dressing supplies Nursing visits Total monthly costs
Exterior catheter
Implanted pump
$9164 $2148
$15,356 $273
$450 $23 $570 $250 $836 $212 $80 $2148
$273
The Bedder et al study suggests that, although the implanted pump is costly in the beginning ($15,356), monthly charges decline to $273. In contrast, the initial cost of the external catheter is lower at $9164, whereas monthly maintenance costs are higher at $2148. (Source: Hassenbusch, SJ: Cost modeling for alternate routes of administration of opioids for cancer Pains. Oncology 13:64, 1999. Used by permission.)
and 8 noncancer pain. The costs of an external catheter included pump rental fee, drug fee (cassette preparations and dispensing fees), supplies, and hospital visits. The implanted pump included costs of the drug, the pump itself, and the operation. The results concluded that the initial cost for a pump was about $15,000, whereas the initial cost for an external catheter was $9000 (Table 1). However, the $9000 amount could be drastically lowered depending on the method of catheter placement and length of hospital stay. Another issue was monthly follow-up costs, which were found to be $2000/ month for the catheter versus $273/month for the implantable pump. Cost efficacy of the pump was noted when patients survived beyond the break-even point, demonstrating cost minimization.
A Theoretical Model From a theoretical perspective, the MD Anderson model was based on the actual charges for various items and their predicted costs for such treatments. The five parameters included: (a) initial charges of screening and delivery of opioids; (b) drug charges for follow up visits; (c) service charges for ongoing check-ups; (d) medical personnel fee; and (e) readmission and/or complications charges. The relative contributions of cost components are illustrated in Fig 1 for oral morphine, transdermal fentanyl, subcutaneous or intravenous morphine delivery, epidural external pump, and intrathecal implanted pump. At 1 month, drug charges accounted for 50% of the cost of oral morphine. Other expenses included home care, whereas clinic and readmission costs for complications were insignificant. Transdermal fentanyl resulted in the same cost breakdown as oral morphine administration. Use of subcutaneous (intravenous) morphine delivery and epidural external pump resulted in lower drug costs, whereas home-care charges increased. According to the Bedder et al study discussed earlier, the charges for an externalized system remain reasonable in the beginning, whereas the high cost of an implanted pump was from the cost of the pump itself with smaller charges for drugs, clinic and home care, and readmission. The study concluded that the more expensive options are either intravenous delivery of morphine or an externalized catheter system. Despite the relative economics of epidural delivery in the beginning, home care, drug charges, the cassette, and pump rentals become increasingly expensive over time due to dose escalation. The model predicts that, over a period of 15 months, an external system may result
Fig 1. Relative contributions of the different cost components for each delivery route. Relative contributions are presented for oral morphine, transdermal fentanyl, subcutaneous or intravenous morphine delivery, the epidural external pump, and the intrathecal implanted pump. (Source: Hassenbusch SJ: Cost modeling for alternate routes of administration of opioids for cancer pains. Oncology 13:64, 1999. Used by permission.)
Cost-Effectiveness of Intraspinal Drug Delivery
in $100,000 to $120,000 in total costs. In contrast, the intrathecal pump has a high initial cost of $15,000 to $20,000 for the pump and the operation to have it implanted. In addition to these high costs, one must also note the possible complications with pump failure or readjustments that might require the patient to be readmitted to the hospital. However, subsequent charges for home care and drug costs are miniscule. In a noncancer setting, the best option would be an implantable pump because it allows for large doses of morphine over a significant amount of time with fewer costs for maintenance. Back Pain Syndrome Studies in a Noncancer Setting In a cost-effective study of intrathecal infusion for chronic back pain, a comparison was made between intrathecal drug therapy versus conventional therapy.2 There were 67 patients with failed back syndrome, 23 of whom had an implantable pump, and 44 served as controls receiving the conventional pain treatment. These patients were observed for a period of 5 years during which the costs were tabulated for diagnostic imaging, professional fees, hardware, nursing visits for pump maintenance, alternative therapies, and hospitalization costs. Patients from both groups responded to the Oswestry Pain Questionnnaire to assess their pain and quality of life posttreatment. The calculated cost for an intrathecal drug pump was $29,410, versus $38,000 for conventional treatment. The initial cost of the pump was high; however, after 28 months, the costs for conventional drug therapy became more expensive. Further indications by the Oswestry Pain Index reported a 27% improvement in patients who underwent pump therapy, with 12% improvement in the control group. The study concluded by indicating that intrathecal drug therapy is cost-effective in the long run despite the high initial costs of the implantable devices. A crucial point is that the study provided no reference to the potential side-effects and possible postoperative complications of intrathecal drug therapy that would require hospitalization. In a study by de Lissovoy et al3 the main objective was to observe the direct cost of intrathecal delivery of morphine versus conventional pain management over a period of 60 months.1 The cost-effectiveness of the pump was calculated based on 65% to 81%
●
Nguyen and Hassenbusch
45
“adequate” to excellent pain relief compared with conventional management. The predicted baseline value (most likely) of pump implantation over 60 months was $82,893 (averaging $1382/month). The calculated best-case scenario (minimal adverse event, low costs) was $53,468 ($891/month), and the estimated worst-case scenario (high adverse event, high costs) was $125,102 ($2085/month). Moreover, the study concluded that for back pain there is an “intersection” at 20 months, which means that, for patients with chronic back pain, it would be cheaper and more effective to have an implanted pump than systemic treatment. It is important to note that drugs are not the primary costs, but rather charges resulting from doctor visits, physical therapy, emergency room visits, and readmissions. The objective here is to minimize the costs of supplemental therapy with maximum pain relief. Assessment of charges for each method of opioid delivery can be estimated using models based on actual vendor quotations, such as in the Bedder et al study, or by using standard charges to create a computer model of predicted costs, such as in the MD Anderson model. There were some important conclusions established by all three models (Bedder et al study, MD Anderson predictive model, and back pain studies). First, there is an apparent break-even point between 3 and 6 months when it becomes more economical to have an implanted system than an external catheter. In a noncancer setting, the break-even point of an implanted pump versus systemic treatment is 1.5 to 2.5 years. One critical note is that these studies did not suggest patients be treated by the most inexpensive approach, but rather sought to analyze charges associated with the different treatments.
References 1. Bedder MD, Burchiel K, Larson A: Cost analysis of two implantable narcotic delivery systems. J Sympt Manag 6:368-373, 1991 2. Kumar K, Hunter G, Demeria DD: Treatment of chronic pain by using intrathecal drug therapy compared with conventional pain therapies: A cost-effective analysis. Neurosurgery 97:803-810, 2002 3. de Lissovoy G, Brown RE, Halpern M, et al: Costeffectiveness of long term intrathecal morphine therapy for pain associated with failed back surgery syndrome. Clin Ther 19:96-112, 1997