Evaluating the Relative Vaccine Effectiveness of Adjuvanted Trivalent Influenza Vaccine Compared to High-Dose Trivalent and Other Egg-Based Influenza Vaccines among Older Adults in the US during the 2017–2018 Influenza Season
Abstract
:1. Introduction
2. Materials and Methods
2.1. Study Overview
2.2. Data Sources
2.3. Study Population
2.4. Study Measures
2.5. Analyses
2.6. Economic Analysis
3. Results
3.1. Study Sample
3.2. Patient Characteristics
3.3. Clinical Outcomes
3.3.1. Influenza-Related Hospitalizations/ER Visits and Office Visits
3.3.2. Cardio-Respiratory Hospitalizations/ER Visits
3.4. Economic Outcomes
4. Discussion
5. Conclusions
Supplementary Materials
Author Contributions
Funding
Acknowledgments
Conflicts of Interest
References
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Vaccine Cohort | aTIV | TIV-HD | SMD 1 | aTIV | QIVe-SD | SMD 1 | aTIV | TIVe-SD | SMD 1 |
---|---|---|---|---|---|---|---|---|---|
Characteristic | N = 234,038 | N = 1,269,897 | - | N = 234,351 | N = 212,120 | - | N = 234,136 | N = 106,495 | - |
Mean Age | 75.0 | 75.0 | 0.01 | 74.8 | 74.4 | −0.06 | 75.1 | 74.6 | −0.09 |
SD | 6.3 | 6.3 | - | 6.3 | 6.7 | - | 6.3 | 6.5 | - |
Median | 74 | 74 | - | 74 | 74 | - | 74 | 74 | - |
Age Group (%) | |||||||||
65–74 years | 51.0% | 50.7% | −0.01 | 53.2% | 53.2% | 0.00 | 50.3% | 53.3% | 0.06 |
75–84 years | 33.4% | 34.0% | 0.01 | 31.7% | 31.7% | 0.00 | 33.8% | 31.6% | −0.05 |
≥85 years | 15.6% | 15.3% | −0.01 | 15.1% | 15.1% | 0.00 | 15.9% | 15.1% | −0.02 |
Gender (%) | |||||||||
Female | 59.6% | 59.9% | 0.01 | 59.3% | 60.6% | 0.03 | 59.5% | 61.7% | 0.04 |
Geographic Region (%) | |||||||||
Northeast | 17.3% | 16.9% | −0.01 | 15.9% | 15.9% | 0.00 | 14.8% | 15.1% | 0.01 |
Midwest | 17.4% | 17.7% | 0.01 | 14.7% | 14.7% | 0.00 | 11.3% | 11.8% | 0.02 |
South | 44.9% | 44.8% | 0.00 | 47.1% | 46.8% | −0.01 | 50.3% | 49.7% | −0.01 |
West | 20.4% | 20.5% | 0.00 | 22.3% | 22.6% | 0.01 | 23.6% | 23.4% | −0.01 |
Payer Type (%) | |||||||||
Third party | 32.2% | 32.1% | 0.00 | 34.2% | 34.3% | 0.00 | 28.5% | 28.6% | 0.00 |
Medicare Part D | 29.6% | 29.5% | 0.00 | 24.9% | 25.0% | 0.00 | 28.0% | 28.8% | 0.02 |
Medicare | 37.6% | 37.7% | 0.00 | 39.7% | 39.6% | 0.00 | 42.4% | 41.5% | −0.02 |
Other/Unknown | 0.7% | 0.7% | 0.00 | 1.2% | 1.1% | 0.00 | 1.2% | 1.1% | −0.01 |
Vaccine Cohort | aTIV | TIV-HD | SMD 1 | aTIV | QIVe-SD | SMD 1 | aTIV | TIVe-SD | SMD 1 |
---|---|---|---|---|---|---|---|---|---|
Characteristic | N = 234,038 | N = 1,269,897 | N = 234,351 | N = 212,120 | N = 234,136 | N = 106,495 | |||
Month of Flu Vaccination (%) | |||||||||
August | 6.0% | 6.1% | 0.00 | 6.1% | 6.0% | −0.01 | 6.3% | 5.7% | −0.03 |
September | 30.4% | 30.9% | 0.01 | 26.6% | 26.6% | 0.00 | 25.5% | 25.2% | −0.01 |
October | 41.1% | 41.1% | 0.00 | 40.9% | 41.0% | 0.00 | 41.2% | 41.6% | 0.01 |
November | 14.3% | 14.0% | −0.01 | 15.4% | 15.3% | 0.00 | 15.5% | 15.6% | 0.00 |
December | 4.7% | 4.5% | −0.01 | 5.9% | 5.9% | 0.00 | 5.9% | 6.0% | 0.01 |
January | 3.5% | 3.4% | −0.01 | 5.1% | 5.2% | 0.00 | 5.7% | 5.8% | 0.01 |
CCI Score (%) | |||||||||
0 | 56.9% | 55.1% | −0.04 | 53.3% | 53.5% | 0.00 | 53.6% | 53.8% | 0.00 |
1 | 20.8% | 21.4% | 0.01 | 21.6% | 21.5% | 0.00 | 21.4% | 21.3% | 0.00 |
2 | 11.9% | 12.3% | 0.01 | 12.8% | 12.8% | 0.00 | 12.8% | 12.7% | 0.00 |
3+ | 10.4% | 11.3% | 0.03 | 12.4% | 12.2% | 0.00 | 12.2% | 12.2% | 0.00 |
Mean CCI Score | 0.9 | 0.9 | 0.04 | 1.0 | 1.0 | 0.00 | 0.9 | 1.0 | 0.01 |
SD | 1.3 | 1.3 | - | 1.4 | 1.4 | - | 1.4 | 1.4 | - |
Median | 0 | 0 | - | 0 | 0 | - | 0 | 0 | - |
Pre-index Comorbidities (%) | |||||||||
Asthma | 3.6% | 3.8% | 0.01 | 4.0% | 3.9% | −0.01 | 3.9% | 4.0% | 0.00 |
Blood Disorders | 0.3% | 0.3% | 0.00 | 0.3% | 0.3% | 0.00 | 0.3% | 0.3% | 0.00 |
Chronic Lung Disease | 8.4% | 8.8% | 0.01 | 9.1% | 9.5% | 0.01 | 9.0% | 9.8% | 0.03 |
Diabetes | 20.0% | 21.6% | 0.04 | 22.1% | 23.6% | 0.03 | 21.8% | 24.1% | 0.06 |
Heart Disease | 12.1% | 12.5% | 0.01 | 13.3% | 13.2% | 0.00 | 13.3% | 13.0% | −0.01 |
Kidney Disorders | 8.2% | 8.8% | 0.02 | 9.5% | 8.8% | −0.02 | 9.5% | 9.0% | −0.02 |
Liver Disorders | 2.1% | 2.1% | 0.00 | 2.4% | 2.4% | 0.00 | 2.3% | 2.4% | 0.00 |
Neurological or Neurodevelopmental Conditions | 4.8% | 4.8% | 0.00 | 5.0% | 5.1% | 0.01 | 5.0% | 4.8% | −0.01 |
Weakened Immune system 2 | 9.7% | 9.9% | 0.01 | 9.8% | 9.8% | 0.00 | 9.8% | 9.4% | −0.01 |
IBD | 0.6% | 0.6% | 0.00 | 0.6% | 0.6% | 0.00 | 0.6% | 0.6% | 0.00 |
Indicators of Frail Health Status (%) | |||||||||
Home oxygen use | 4.1% | 4.0% | 0.00 | 4.3% | 4.4% | 0.00 | 4.3% | 4.4% | 0.00 |
Wheelchair use | 2.2% | 2.3% | 0.01 | 2.3% | 2.7% | 0.03 | 2.3% | 2.5% | 0.02 |
Walker use | 3.3% | 3.3% | 0.00 | 3.4% | 3.5% | 0.01 | 3.4% | 3.5% | 0.01 |
Dementia | 1.3% | 1.3% | 0.00 | 1.4% | 1.2% | −0.01 | 1.4% | 1.3% | 0.00 |
Urinary catheter use | 0.4% | 0.4% | 0.00 | 0.5% | 0.4% | −0.01 | 0.5% | 0.4% | −0.02 |
Falls | 0.9% | 0.9% | 0.00 | 0.9% | 0.8% | −0.01 | 0.9% | 0.9% | 0.00 |
Fractures | 0.6% | 0.6% | 0.00 | 0.6% | 0.5% | −0.01 | 0.6% | 0.6% | 0.00 |
Pre-index hospitalization (%) | 7.8% | 7.9% | 0.00 | 8.2% | 7.8% | −0.01 | 8.2% | 7.7% | −0.02 |
Mean pre-index outpatient pharmacy costs | $2398 | $2430 | 0.01 | $2473 | $2323 | −0.03 | $2449 | $2479 | 0.01 |
SD | $5924 | $5488 | $6010 | $5918 | $6011 | $5244 | |||
Median | $852 | $889 | $885 | $786 | $879 | $959 | |||
Mean pre-index inpatient costs | $827 | $825 | 0.00 | $927 | $839 | −0.01 | $925 | $846 | −0.01 |
SD | $9156 | $7774 | $9997 | $9983 | $10,191 | $8009 | |||
Median | $0 | $0 | $0 | $0 | $0 | $0 | |||
Mean pre-index outpatient medical costs | $1734 | $1696 | −0.01 | $1822 | $1633 | −0.03 | $1812 | $1624 | −0.03 |
SD | $6347 | $6621 | $6523 | $6409 | $6463 | $6493 | |||
Median | $400 | $397 | $419 | $371 | $416 | $361 | |||
Mean TOTAL pre-index costs 3 | $4958 | $4951 | 0.01 | $5221 | $4795 | −0.08 | $5186 | $4950 | −0.02 |
SD | $13,353 | $12,259 | $14,116 | $13,852 | $14,214 | $12,259 | |||
Median | $2028 | $2051 | $2112 | $1856 | $2100 | $2039 |
Predicted Mean Annualized Cost | aTIV N = 234,313 | TIV-HD N = 234,313 | Incremental Mean | ||
---|---|---|---|---|---|
Mean | 95% CIs | Mean | 95% CIs | ||
All-cause total | $9999 | $9925–$10,069 | $10,022 | $9963–$10,088 | $23.24 |
Influenza-related total | $28.21 | $24.60–$32.39 | $31.77 | $27.73–$36.26 | $3.56 |
Influenza-related hospitalizations | $27.59 | $23.00–$32.85 | $26.29 | $22.41–$30.81 | −$1.30 |
Influenza-related ER | $3.97 | $3.52–$4.43 | $4.49 | $3.99–$4.97 | $0.52 |
Influenza-related office visit + oseltamivir | $1.10 | $1.04–$1.17 | $1.36 | $1.29–$1.45 | $0.26 |
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Pelton, S.I.; Divino, V.; Shah, D.; Mould-Quevedo, J.; DeKoven, M.; Krishnarajah, G.; Postma, M.J. Evaluating the Relative Vaccine Effectiveness of Adjuvanted Trivalent Influenza Vaccine Compared to High-Dose Trivalent and Other Egg-Based Influenza Vaccines among Older Adults in the US during the 2017–2018 Influenza Season. Vaccines 2020, 8, 446. https://doi.org/10.3390/vaccines8030446
Pelton SI, Divino V, Shah D, Mould-Quevedo J, DeKoven M, Krishnarajah G, Postma MJ. Evaluating the Relative Vaccine Effectiveness of Adjuvanted Trivalent Influenza Vaccine Compared to High-Dose Trivalent and Other Egg-Based Influenza Vaccines among Older Adults in the US during the 2017–2018 Influenza Season. Vaccines. 2020; 8(3):446. https://doi.org/10.3390/vaccines8030446
Chicago/Turabian StylePelton, Stephen I., Victoria Divino, Drishti Shah, Joaquin Mould-Quevedo, Mitch DeKoven, Girishanthy Krishnarajah, and Maarten J. Postma. 2020. "Evaluating the Relative Vaccine Effectiveness of Adjuvanted Trivalent Influenza Vaccine Compared to High-Dose Trivalent and Other Egg-Based Influenza Vaccines among Older Adults in the US during the 2017–2018 Influenza Season" Vaccines 8, no. 3: 446. https://doi.org/10.3390/vaccines8030446