Clinical simulation model of long-acting opioids for treatment of chronic non-cancer pain in the United States

Figures & data

Figure 1.  Overview of the model structure.

Figure 2.  Opioid initiation and titration: detail.

Table 1.  Days duration, management, and utilization associated with TEAE.

	Nausea/ Vomiting9–11,17,18	Pruritus17,18	Dizziness17	Somnolence17,18	Constipation (Acute)5,17,18	Constipation (Chronic)5,19
Days duration of TEAE	10	3	1	1	3	Duration of LAO
% of patients who seek medical contact17	29%	17%	21%	11%	23%	–
Of the patients seeking medical contact, % who switch LAO due to TEAE	12.2%	5.1%	6.5%	3.7%	12%	–
Medical contact
Scheduled primary care OV	–	–	–	–	–	10%
Unscheduled primary care OV	18%	9%	10%	7%	12%	10%
Telephone consult	7%	8%	10%	4%	9%	–
ED visit	1%	–	1%	–	1%	–
Inpatient admission	3%	–	–	–	1%	–
Pharmacy
Rx anti-emetic	29%	–	–	–	–	–
Rx psycho-stimulant	–	–	–	3%	–	–
Rx stool softener	–	–	–	–	11.4%	11.4%
Rx laxative	–	–	–	–	6.4%	11.4%
Diagnostics
X-ray (pelvis)	–	–	–	–	–	5%
CT scan (abdominal)	–	–	–	–	–	2%
MRI (abdominal)	–	–	–	–	–	1%
Weighted cost per event**	$104.49	$15.65	$24.18	$11.83	$50.95	$0.01*

OV, office visit; ED, emergency department; Rx, prescription; MRI, magnetic resonance imaging.

*Daily cost for management of chronic constipation for the duration of the LAO therapy.

**2012 US dollars.

Table 2.  Opioid failure: component costs.

Cost frequency	Medical resource	Units	% of patients	Rationale
One-time	Diagnostics			Baseline estimate assumes that each patient is assessed using one type of imaging study5.
	X-ray	2	25.0%
	CT scan	1	25.0%
	MRI	1	25.0%
	Myelography	1	25.0%
	Medical Contact			Assumption
	Office visit, complex	2	100.0%
	Interventions			Baseline estimate assumes that 13% of patients receive OA-related joint surgery20, 10% receive no further treatment (assumption), and the remaining patients would be equally split between nerve block injections and epidural pain blockade (assumption).
	Surgical intervention	1	13.0%
	Nerve block injection	1	38.5%
	Epidural pain blockade	1	38.5%
	No further treatment	–	10.0%
Daily	Pain control			Assumption
	Buprenorphine/naloxone	16.4 mg/day	100.0%
	Physical therapy	Once/month	100.0%

Table 3.  Utilities.

Health state	Utility (per day)	Disutility (per day)
Adequate pain relief/ No side-effects (referent case)	0.88
Inadequate pain relief		0.13
Constipation TEAE		0.14
Nausea/vomiting TEAE		0.20
Dizziness TEAE		0.22
Somnolence TEAE		0.22
Pruritus TEAE		0.00

Source: Schmier et al.21

Table 4.  Workplace productivity.

Event	Productivity loss (hours)
Phone call to doctor’s office	0.50
Office visit, scheduled	2.00
Office visit, unscheduled	2.00
Walk-in clinic visit	2.00
Emergency department visit	4.00
Inpatient admission	8.00
X-ray (radiography, pelvis)	2.00
CT scan (abdominal, no contrast)	2.00
MRI (abdominal)	2.00
Myelography	2.00
Nerve block injections	2.00
Epidural pain blockade	2.00
Surgical intervention*	240.00
Inadequate pain relief	1.04
Constipation TEAE (per day)	0.35
Nausea/vomiting TEAE (per day)	0.55
Dizziness TEAE (per day)	0.45
Somnolence TEAE (per day)	0.62
Pruritus TEAE (per day)	0.00
Breakthrough (flare) pain (per day)	0.26
Worsening pain (per day)	1.04

*Based on 40-hour work week and 6-week recovery period.

Table 5.  Unit costs.

Cost category	Unit	Unit cost*	Notes
Pharmacy
Tapentadol ER	50 mg	$2.55
	100 mg	$4.71
	150 mg	$6.07
	200 mg	$7.73
	250 mg	$7.73
Oxycodone CR	10 mg	$2.02	**Cost of 50 mg unit (100 mg daily dose) calculated as cost of a 20 mg unit + the cost of a 30 mg unit.
	20 mg	$3.87
	30 mg	$5.47
	40 mg	$6.86
	50 mg**	$9.34
Alternate LAO	day	$6.74	Weighted average cost of branded and generic fentanyl, hydromorphone, and morphine sulfate
Rx stool softener	day	$0.04	docusate sodium (150 mg bid)
Rx laxative	day	$0.11	bisacodyl (10 mg qd)
Rx anti-emetic	day	$0.45	metoclopromide (5 mg q 6 h/day)
Rx psychostimulant	day	$4.16	methylphenidate (30 mg qd)
burprenorphine/naloxone	day	$14.77	16/4 mg once-daily
Rx lactulose	day	$2.06	Weighted average cost of branded and generic
Medical Contact
Office visit, scheduled	each	$67.89
Office visit, unscheduled	each	$150.20
Phone call to doctor’s office	each	$26.71
Walk-in clinic visit	each	$67.89
Emergency department visit	each	$849.18
Inpatient admission	each	$2,201.42
Physical therapy session	each	$77.00
Tests
X-ray (pelvis)	each	$38.00
CT scan (abdominal, no contrast)	each	$349.00
MRI (abdominal)	each	$860.00
Myelography	each	$285.00
Interventions
Nerve block injections	each	$194.00
Epidural pain blockade	each	$451.00
Surgical intervention	each	$19,224.00

*2012 US dollars.

Table 6.  Summary 1-year results (clinical, humanistic variables).

End-point*	Tapentadol ER	Oxycodone CR	Difference (tapentadol ER – oxycodone CR)	Advantage tapentadol ER
% of patients who achieve adequate pain relief + no GI TEAE
Mean	29%	15%	14%	50/50 runs
SD	1.41%	1.03%	1.68%
# days free of any (acute) TEAE
Mean	362	359	3	50/50 runs
SD	0.14	0.18	0.22
# days free of chronic constipation
Mean	343	318	25	50/50 runs
SD	2.32	3.26	3.77
# office visits, routine
Mean	11.52	11.19	0.33	2/50 runs
SD	0.14	0.14	0.19
# office visits, unscheduled
Mean	0.15	0.27	(0.12)	50/50 runs
SD	0.00	0.01	0.01
# TEAE
Mean	0.74	1.27	(0.53)	50/50 runs
SD	0.02	0.03	0.04
# opioid failures
Mean	0.25	0.27	(0.02)	37/50 runs
SD	0.01	0.01	0.02
% patients who remain on initial LAO
Mean	42%	38%	4%	49/50 runs
SD	1.35%	1.66%	2.13%
Quality-adjusted life days (QALD)
Mean	295	284	11	50/50 runs
SD	0.69	0.79	0.91
Productive Working Hours
Mean	1927	1915	12	49/50 runs
SD	4.16	4.13	5.44

*All end-points refer to per-patient average annual outcomes. Thus, a difference of one office visit per-patient would represent a difference of 1000 office visit in a panel of 1000 patients.

Table 7.  Summary results (costs).

End-point*	Tapentadol ER	Oxycodone CR	Difference (tapentadol ER – oxycodone CR)	Advantage tapentadol ER
Cost of LAO
Mean	$2632	$2328	$305	0/50 runs
SD	$42.13	$40.28	$52.76
Costs of office visits, routine
Mean	$1012	$1012	$0.50	26/50 runs
SD	$17.26	$14.40	$22.00
Cost of office visits, unscheduled
Mean	$44.64	$79.57	($34.93)	50/50 runs
SD	$1.78	$1.92	$2.56
Cost of opioid failure
Mean	$2246	$2387	($141)	43/50 runs
SD	$114.86	$114.51	$156.71
Total costs
Mean	$5935	$5806	$129	3/50 runs
SD	$66.91	$72.24	$98.57

*All end-points refer to per-patient average annual outcomes. Thus, a difference of one office visit per-patient would represent a difference of 1000 office visit in a panel of 1000 patients.

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