Influenza Vaccine Effectiveness in Preventing Severe Outcomes in Patients Hospitalized with Laboratory-Confirmed Influenza during the 2017–2018 Season. A Retrospective Cohort Study in Catalonia (Spain)
Abstract
:1. Introduction
2. Materials and Methods
Statistical Analysis
3. Results
4. Discussion
Author Contributions
Funding
Institutional Review Board Statement
Informed Consent Statement
Data Availability Statement
Acknowledgments
Conflicts of Interest
References
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Patient Parameters | Total Number of Hospitalized Influenza Cases n = 1414 | Vaccinated Cases n = 465 (32.9%) | Unvaccinated Cases n = 949 (67.1%) | p Value a | d-Cohen/ w-Cohen |
---|---|---|---|---|---|
Age mean (SD) b | 71.5 (15.2) | 77.6 (11.3) | 68.5 (16.0) | <0.001 | 0.62 |
Age group | |||||
≥60 years | 1118 (79.1%) | 437 (94.0%) | 681 (71.8%) | 0.000 | 0.26 |
18–59 years | 296 (20.9%) | 28 (6.0%) | 268 (28.2%) | ||
Sex | |||||
Male | 804 (56.9%) | 269 (57.8%) | 535 (56.4%) | 0.600 | 0.01 |
Female | 610 (43.1%) | 196 (42.2%) | 414 (43.6%) | ||
Comorbidities (≥1) | |||||
Yes | 1127 (79.7%) | 406 (87.3%) | 721 (76.0%) | <0.001 | 0.13 |
No | 287 (20.3%) | 59 (12.7%) | 228 (24.0%) | ||
COPD c | |||||
Yes | 461 (32.6%) | 190 (40.9%) | 271 (28.6%) | <0.001 | 0.12 |
No | 953 (67.4%) | 275 (59.1%) | 678 (71.4%) | ||
Obesity (BMI > 40) d | |||||
Yes | 111 (7.85%) | 37 (8.0%) | 74 (7.8%) | 0.909 | 0.003 |
No | 1303 (92.1%) | 428 (92.0%) | 875 (92.2%) | ||
Diabetes | |||||
Yes | 385 (27.2%) | 141 (30.3%) | 244 (25.7%) | 0.069 | 0.05 |
No | 1029 (72.8%) | 324 (69.7%) | 705 (74.3%) | ||
Chronic renal disease | |||||
Yes | 275 (19.4%) | 106 (22.8%) | 169 (17.8%) | 0.028 | 0.06 |
No | 1139 (80.6%) | 359 (77.2%) | 780 (82.2%) | ||
Immunodeficiency | |||||
Yes | 230 (16.3%) | 68 (14.6%) | 162 (17.1%) | 0.242 | 0.03 |
No | 1184 (83.7%) | 397 (85.4%) | 787 (82.9%) | ||
Cardiovascular disease | |||||
Yes | 614 (43.4%) | 237 (51.0%) | 377 (39.7%) | <0.001 | 0.10 |
No | 800 (56.6%) | 228 (49.0%) | 572 (60.3%) | ||
Chronic liver disease | |||||
Yes | 88 (6.22%) | 28 (6.0%) | 60 (6.3%) | 0.836 | 0.006 |
No | 1326 (93.8%) | 437 (94.0%) | 889 (93.7%) | ||
Other comorbidities e | |||||
Yes | 165 (11.7%) | 66 (14.2%) | 99 (10.4%) | 0.041 | 0.06 |
No | 1249 (88.3%) | 399 (85.8%) | 850 (89.6%) | ||
NI f treatment | |||||
Yes | 1299 (91.9%) | 437 (94.0%) | 862 (90.9%) | 0.045 | 0.05 |
NI f treatment (timing) | |||||
≤48 h from onset of symptoms | 511 (36.9%) | 169 (36.3%) | 342 (36.1%) | 0.075 | 0.05 |
>48 h from onset of symptoms | 759 (54.8%) | 257 (55.3%) | 502 (53.0%) | 0.046 | |
No | 114 (8.1%) | 28 (6.0%) | 86 (9.1%) | ||
Type of influenza virus | |||||
B | 859 (60.9%) | 295 (63.4%) | 564 (59.7%) | 0.174 | 0.04 |
A | 551 (39.1%) | 170 (36.6%) | 381 (40.3%) | ||
Outcome variables: | |||||
ICU admission | |||||
Yes | 214 (15.1%) | 52 (11.2%) | 162 (17.1%) | 0.005 | 0.08 |
No | 1200 (84.9%) | 413 (88.8%) | 787 (82.9%) | ||
LOS g | |||||
Mean days (SD) | 12.8 (15.9) | 12.1 (14.1) | 13.1 (16.8) | 0.228 | 0.06 |
ICU LOS h | |||||
Mean days (SD) | 9.35 (10.4) | 9.49 (9.30) | 9.31 (10.8) | 0.917 | 0.02 |
Patient Parameters | SHLCI a n = 1227 | HLCI b n = 187 | p Value | d-Cohen/ w-Cohen |
---|---|---|---|---|
Age, mean (SD) c | 71.1 (15.3) | 68.5 (16.0) | 0.008 * | 0.17 |
Age group | ||||
≥60 years | 959 (78.2%) | 159 (85.0%) | 0.040 | 0.06 |
18–59 years | 268 (21.8%) | 28 (15.0%) | ||
Sex | ||||
Male | 709 (57.8%) | 95 (50.8%) | 0.086 | 0.05 |
Female | 518 (42.2%) | 92 (49.2%) | ||
Comorbidities (≥1) | ||||
Yes | 956 (77.9%) | 171 (91.4%) | <0.001 | 0.11 |
No | 271 (22.1%) | 16 (8.56%) | ||
Influenza vaccination | ||||
Yes | 440 (35.9%) | 25 (13.4%) | <0.001 | 0.16 |
No | 787 (64.1%) | 162 (86.6%) | ||
NI d treatment | ||||
Yes | 1146 (93.4%) | 153 (81.8%) | <0.001 | 0.14 |
No | 81 (6.60%) | 34 (18.2%) | ||
NI d treatment (timing) | ||||
≤48 h from symptom onset | 452 (37.7%) | 59 (31.7%) | <0.001 | 0.14 |
>48 h from symptom onset | 665 (55.5%) | 94 (50.5%) | ||
No | 81 (6.8%) | 33 (17.7%) |
Patient Parameters | ICU Admission n = 214 (15.1%) | No ICU Admission n = 1200 (84.9%) | p Value | d-Cohen/ w-Cohen |
---|---|---|---|---|
Influenza vaccination | ||||
Yes | 52 (11.2%) | 413 (88.8%) | 0.003 | 0.08 |
No | 162 (17.1%) | 787 (82.9%) | ||
Age | ||||
Years, mean (SD) b | 64.0 (13.6) | 72.8 (15.1) | <0.001 * | 0.59 |
Age group | ||||
≥60 years | 141 (12.6%) | 977 (87.4%) | <0.001 | 0.14 |
18–59 years | 73 (24.7%) | 223 (75.3%) | ||
Sex | ||||
Male | 135 (16.8%) | 669 (83.2%) | 0.046 | 0.05 |
Female | 79 (13.0%) | 531 (87.0%) | ||
Comorbidities | ||||
Yes | 164 (14.6%) | 963 (85.4%) | 0.230 | 0.03 |
No | 50 (17.4%) | 237 (82.6%) | ||
COPD c | ||||
Yes | 74 (16.1%) | 387 (83.9%) | 0.502 | 0.02 |
No | 140 (14.7%) | 813 (85.3%) | ||
Obesity (BMI > 30) d | ||||
Yes | 23 (20.7%) | 88 (79.3%) | 0.098 | 0.05 |
No | 191 (14.7%) | 1112 (85.3%) | ||
Diabetes | ||||
Yes | 60 (15.6%) | 325 (84.4%) | 0.767 | 0.01 |
No | 154 (15.0%) | 875 (85.0%) | ||
Chronic renal disease | ||||
Yes | 31 (11.3%) | 244 (88.7%) | 0.043 | 0.05 |
No | 183 (16.1%) | 956 (83.9%) | ||
Immunodeficiency | ||||
Yes | 33 (14.3%) | 197 (85.7%) | 0.728 | 0.01 |
No | 181 (15.3%) | 1003 (84.7%) | ||
Cardiovascular disease | ||||
Yes | 79 (12.9%) | 535 (87.1%) | 0.037 | 0.05 |
No | 135 (16.9%) | 665 (83.1%) | ||
Chronic liver disease | ||||
Yes | 24 (27.3%) | 64 (72.7%) | 0.002 | 0.09 |
No | 190 (14.3%) | 1136 (85.7%) | ||
Other comorbidities e | ||||
Yes | 27 (16.4%) | 138 (83.6%) | 0.630 | 0.01 |
No | 187 (15.0%) | 1062 (85.0%) | ||
NI f treatment | ||||
Yes | 199 (15.3%) | 1100 (84.7%) | 0.552 | 0.02 |
No | 15 (13.2%) | 99 (86.8%) | ||
NI f treatment (timing) | ||||
≤48 h from symptom onset | 62 (12.1%) | 449 (87.9%) | 0.750 | 0.06 |
>48 h from symptom onset | 128 (16.9%) | 631 (83.1%) | 0.323 | |
No | 15 (13.2%) | 99 (86.8%) | ||
Influenza virus type | ||||
A | 92 (16.7%) | 459 (83.3%) | ||
B | 122 (14.2%) | 737 (85.8%) | 0.205 | 0.04 |
LOS g | ||||
Mean days (SD) b | 22.4 (20.3) | 11.1 (14.4) | <0.001 * | 0.73 |
All Patients | ICU Admission | No ICU Admission | aVE a | p Value |
---|---|---|---|---|
n = 1414 | n = 214 (15.1%) | n = 1200 (84.9%) | (95%CI) b | |
Influenza vaccination Vaccinated (465; 32.9%) | 52 (11.2%) | 413 (88.8%) | 31% (1; 52) | 0.04 |
Unvaccinated (949; 67.1%) | 162 (17.1%) | 787 (82.9%) | Ref. | |
Influenza B n = 859 (60.7%) | ||||
Vaccinated (295; 34.3%) | 33 (11.2%) | 262 (88.8%) | 25% (−18; 52) | 0.21 |
Unvaccinated (564; 65.7%) | 89 (15.8%) | 475 (84.2%) | Ref. | |
Influenza A n = 551 (38.9%) | ||||
Vaccinated (170; 30.9%) | 19 (11.2%) | 151 (88.8%) | 40% (−11; 68) | 0.09 |
Unvaccinated (381; 69.1%) | 73 (19.2%) | 308 (80.8%) | Ref. | |
Female, age <60 years n = 125 (8.8%) | ||||
Vaccinated (14; 11.2%) | 1 (7.1%) | 13 (92.9%) | 72% (−135; 97) | 0.24 |
Unvaccinated (111; 88.8%) | 28 (25.2%) | 83 (74.8%) | Ref. | |
Female, age ≥60 years n = 485 (34.3%) | ||||
Vaccinated (182; 37.5%) | 17 (9.3%) | 165 (90.7%) | 23% (−48; 60) | 0.43 |
Unvaccinated (303; 62.5%) | 33 (10.9%) | 270 (89.1%) | Ref. | |
Male, age <60 years n = 171 (24.2%) | ||||
Vaccinated (14; 8.2%) | 3 (21.4%) | 11 (78.6%) | 29% (−74; 82) | 0.62 |
Unvaccinated (157; 91.8%) | 41(26.1%) | 116 (73.9%) | Ref. | |
Male, age ≥60 years n = 633 (44.7%) | ||||
Vaccinated (255; 40.3%) | 31 (12.2%) | 224 (87.8%) | 32% (−10; 58) | 0.12 |
Unvaccinated (378; 59.7%) | 60(15.9%) | 318 (84.1%) | Ref. |
ICU Admission | No ICU Admission | VE * | aVE ** | p Value | |
---|---|---|---|---|---|
All Patients n = 1414 | n = 214 (15.1%) | n = 1200 (84.9%) | (95% CI) | (95% CI) | |
Influenza vaccination | |||||
Vaccinated (465; 32.9%) | 52 (11.2%) | 413 (88.8%) | 39% (15; 56) | 31% (1; 52) | 0.040 |
Unvaccinated (949; 67.1%) | 162 (17.1%) | 787 (82.9%) | Ref. | ||
SHLCI a n = 1227 | 210 (17.1%) | 1017 (82.9%) | |||
Vaccinated (440: 35.9%) | 52 (11.8%) | 388 (88.2%) | 47% (25; 62) | 40% (13; 58) | 0.007 |
Unvaccinated (787; 64.1%) | 158 (20.1%) | 629 (79.9%) | |||
HLCI b n = 187 | 4 (2.1%) | 183 (97.9%) | |||
Vaccinated (25; 13.3%) | 0 (0.0%) | 25 (100%) | 31% (−578; 99.5) *** | Not computable | ---- |
Unvaccinated (162; 86.7%) | 4 (2.5%) | 158 (97.5%) |
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Acosta, L.; Soldevila, N.; Torner, N.; Martínez, A.; Ayneto, X.; Rius, C.; Jané, M.; Domínguez, A.; the Influenza Surveillance Network of Catalonia, PIDIRAC. Influenza Vaccine Effectiveness in Preventing Severe Outcomes in Patients Hospitalized with Laboratory-Confirmed Influenza during the 2017–2018 Season. A Retrospective Cohort Study in Catalonia (Spain). Viruses 2021, 13, 1465. https://doi.org/10.3390/v13081465
Acosta L, Soldevila N, Torner N, Martínez A, Ayneto X, Rius C, Jané M, Domínguez A, the Influenza Surveillance Network of Catalonia, PIDIRAC. Influenza Vaccine Effectiveness in Preventing Severe Outcomes in Patients Hospitalized with Laboratory-Confirmed Influenza during the 2017–2018 Season. A Retrospective Cohort Study in Catalonia (Spain). Viruses. 2021; 13(8):1465. https://doi.org/10.3390/v13081465
Chicago/Turabian StyleAcosta, Lesly, Nuria Soldevila, Nuria Torner, Ana Martínez, Xavier Ayneto, Cristina Rius, Mireia Jané, Angela Domínguez, and the Influenza Surveillance Network of Catalonia, PIDIRAC. 2021. "Influenza Vaccine Effectiveness in Preventing Severe Outcomes in Patients Hospitalized with Laboratory-Confirmed Influenza during the 2017–2018 Season. A Retrospective Cohort Study in Catalonia (Spain)" Viruses 13, no. 8: 1465. https://doi.org/10.3390/v13081465
APA StyleAcosta, L., Soldevila, N., Torner, N., Martínez, A., Ayneto, X., Rius, C., Jané, M., Domínguez, A., & the Influenza Surveillance Network of Catalonia, PIDIRAC. (2021). Influenza Vaccine Effectiveness in Preventing Severe Outcomes in Patients Hospitalized with Laboratory-Confirmed Influenza during the 2017–2018 Season. A Retrospective Cohort Study in Catalonia (Spain). Viruses, 13(8), 1465. https://doi.org/10.3390/v13081465