High-dose inactivated influenza vaccine is associated with cost savings and better outcomes compared to standard-dose inactivated influenza vaccine in Canadian seniors

Figures & data

Table 1. Outcomes per vaccine.

	Full analysis set			Cardiorespiratory condition analysis set
Outcomes	IIV-HD vaccine n = 15,990	SD vaccine n = 15,993	Difference (IIV-HD-SD)	IIV-HD vaccine n = 15,990	SD vaccine n = 15,993	Difference (IIV-HD-SD)
Uses of prescription medications	0.1977	0.1985	−0.0008	0.0085	0.0087	−0.0002
Uses of non-prescription medications	0.1811	0.1839	−0.0028	0.0061	0.0081	−0.0020
ER visits	0.0131	0.0128	0.0003	0.0004	0.0003	0.0001
Non-routine/urgent care visits	0.2257	0.2179	0.0078	0.0071	0.0074	−0.0003
Hospitalizations	0.0937	0.1017	−0.0080	0.0248	0.0296	−0.0048
Deaths	0.0052	0.0053	−0.0001	0.0016	0.0025	−0.0009
Life-years	9.8505	9.8502	0.0003	9.8851	9.8762	0.0089
QALYs	7.5533	7.5530	0.0003	7.5882	7.5813	0.0069

Table 2. Costs by resource item (in Canadian dollars/participant).

	Full analysis set			Cardiorespiratory condition analysis set
Outcomes	IIV-HD vaccine n = 15,990	SD vaccine n = 15,993	Difference (IIV-HD-SD)	IIV-HD vaccine n = 15,990	SD vaccine n = 15,993	Difference (IIV-HD-SD)
Study vaccine	$31.81	$5.84	$25.97	$31.81	$5.84	$25.97
Prescription medications	$3.45	$3.45	$0.00	$0.18	$0.19	−$0.01
ER visits	$6.63	$6.47	$0.16	$0.19	$0.13	$0.06
Non-routine/ urgent care visits	$19.21	$18.55	$0.66	$0.60	$0.63	−$0.03
Hospitalizations	$616.47	$690.42	−$73.95	$170.61	$217.26	−$46.65
Total healthcare payer costs	$677.57	$724.72	−$47.15	$203.40	$224.05	−$20.65
Non-prescription medications	$0.32	$0.34	−$0.02	$0.01	$0.01	$0.00
Productivity losses	$136.72	$149.45	−$12.73	$27.28	$35.94	−$8.66
Total societal costs	$814.61	$874.52	−$59.91	$230.70	$259.99	−$29.29

Table 3. Cost utility analysis.

		Full analysis set					Cardiorespiratory condition analysis set
Population	Treatment group	Cost /Subject ($CDN)	Difference in cost ($CDN)	QALYs /Subject	Difference in QALYs	ICER (cost/QALY)	Cost /Subject ($CDN)	Difference in cost ($CDN)	QALYs /Subject	Difference in QALYs	ICER (cost/QALY)
Public Payer perspective
All subjects	IIV-HD (n = 15,990)	$678		7.5533			$203		7.5882
	SD (n = 15,993)	$725	$47	7.5530	−0.0003	Dominated	$224	$21	7.5813	−0.0069	Dominated
Subjects with 1+ comorbid conditions	IIV-HD (n = 10,750)	$831		7.5411			$257		7.5853
	SD (n = 10,752)	$876	$45	7.5399	−0.0012	Dominated	$293	$36	7.5750	−0.0103	Dominated
Subjects 75 + years of age	IIV-HD (n = 5,409)	$892		7.5242			$265		7.5807
	SD (n = 5,430)	$892	<$1	7.5194	0.0049	$82	$292	$27	7.5659	−0.0148	Dominated
Societal perspective
All subjects	IIV-HD (n = 15,990)	$815		7.5533			$231		7.5882
	SD (n = 15,993)	$875	$60	7.5530	−0.0003	Dominated	$260	$29	7.5813	−0.0069	Dominated
Subjects with 1+ comorbid conditions	IIV-HD (n = 10,750)	$996		7.5411			$292		7.5853
	SD (n = 10,752)	$1,055	$59	7.5399	−0.0012	Dominated	$340	$47	7.5750	−0.0103	Dominated
Subjects 75 + years of age	IIV-HD (n = 5,409)	$1,062		7.5242			$303		7.5807
	SD (n = 5,430)	$1,072	$10	7.5194	−0.0049	Dominated	$340	$37	7.5659	−0.0148	Dominated

Table 4. Unit Costs of Resource Items (2014 Canadian dollars).

Resource Item	Cost/Unit	Reference
IIV-HD (Fluzone® High-Dose) vaccine	$31.823/injection	[15]
SD vaccine	$5.82/injection	Sanofi Pasteur
Ibuprofen, 200 mg, 3 and a half times daily for 4 d (non-prescription)	$1.54/course	[19]
Ibuprofen, 600 mg, 3 times daily for 4 d (prescription)	$10.53/prescription	[17]
Oseltamivir, 75 mg, twice daily for 5 d (prescription)	$52.45/prescription	[17]
Azithromycin, 500 mg day 1, 250 mg days 2–5 (prescription)	$17.30/prescription	[17]
Emergency department visit	$506.53/visit	[20, 21]
Non-routine medical office / urgent care visit	$85.13/visit	[21]
Hospitalization per diems	dependent on ICD-10 code (n = 146)	[22]
Daily wage	$188.40/day	[24]

Figure 1. Scatter plots representing the statistical uncertainty through 1,000 bootstrapped samples. Panel A) represents the full analysis set. 89% of bootstrapped data showed that IIV-HD was cost-saving. Panel B) represents data from the cardio-respiratory condition analysis set. 80% of the bootstrapped data showed that IIV-HD was cost-saving and more effective.

Centers for Medicare & Medicaid Services. Seasonal Influenza Vaccines Pricing. 2014. Available at: http://www.cms.gov/Medicare/Medicare-Fee-for-Service-Part-BDrugs/McrPartBDrugAvgSalesPrice/VaccinesPricing.html

 Google Scholar

Canadian Institute for Health Information. Physician services benefit rates report, Canada, 2012-2013. Available at: https://secure.cihi.ca/free_products/PSBR-2013_2014_EN_web.pdf

 Google Scholar

Canadian Association for Pharmacy Distribution Management (CAPDM). Guidebook on Government Drug Reimbursement Plans and Related Programs 2014.

 Google Scholar

Molinari NA, Ortega-Sanchez IR, Messonnier ML, Thompson WW, Wortley PM, Weintraub E, Bridges CB. The annual impact of seasonal influenza in the US: measuring disease burden and costs. Vaccine 2007; 25:5086-96; PMID:17544181; http://dx.doi.org/10.1016/j.vaccine.2007.03.046

 PubMed Web of Science ®Google Scholar

Statistics Canada. Table 281-0063 - Employment and average weekly earnings including overtime (SEPH), seasonally adjusted, for all employees by industries classified using the North American Industry Classification System (NAICS), monthly (persons unless otherwise noted). 2014. Available at: http://www5.statcan.gc.ca/cansim/a26?lang=eng&id=2810063

 Google Scholar

DiazGranados CA, Robertson CA, Talbot HK, Landolfi V, Dunning AJ, Greenberg DP. Prevention of serious events in adults 65 years of age or older: A comparison between high-dose and standard-dose inactivated influenza vaccines. Vaccine 2015; 33:4988-93; PMID:26212007; http://dx.doi.org/10.1016/j.vaccine.2015.07.006

 PubMed Web of Science ®Google Scholar