Skip to main content

Table 4 Subject characteristics and risk of admission with influenza

From: Influenza epidemiology and influenza vaccine effectiveness during the 2014–2015 season: annual report from the Global Influenza Hospital Surveillance Network

  All admissions Influenza-positive Crude OR Heterogeneity by strain (I2)a aORb
  N = 9164 N = 2177
Characteristic n n % Value 95 % CI Value 95 % CI
Age
 0–1 y 1515 144 9.5 1.00 - 32.5 % 1.00 -
 2–4 y 2206 429 19.4 2.30 1.88-2.81 0.0 % 2.14 1.74-2.64
 5–17 y 827 280 33.9 4.87 3.90-6.10 73.3 % 4.34 3.42-5.51
 18–49 y 1461 423 29.0 3.88 3.16-4.77 59.2 % 3.11 2.49-3.90
 50–64 y 748 191 25.5 3.26 2.57-4.14 72.5 % 4.08 3.11-5.36
 65–74 y 819 211 25.8 3.30 2.62-4.17 67.8 % 4.99 3.76-6.64
 75–84 y 1227 294 24.0 3.00 2.42-3.72 62.4 % 4.51 3.43-5.92
 ≥85 811 205 25.3 3.22 2.55-4.07 71.2 % 4.79 3.59-6.40
Sexc
 Male 5417 1141 21.1 1.00 - 0.0 % 1.00 -
 Female 4197 1036 24.7 1.24 1.13-1.37 0.0 % 1.21 1.09-1.34
 Female non-pregnant 3899 876 22.5 1.11 1.00-1.22 0.0 % 1.10 0.99-1.23
Other risk factors (excludes pregnant women)
 Comorbidityd 3709 856 23.1 1.15 1.04-1.27 62.8 % 1.48 1.30-1.69
 Cardiovascular disease 1996 468 23.4 1.17 1.04-1.33 22.2 % 1.47 1.25-1.72
 Chronic obstructive pulmonary disease 1458 306 21.0 1.02 0.88-1.17 57.6 % 1.39 1.15-1.68
 Asthma 440 96 21.8 1.07 0.84-1.35 0.0 % 1.37 1.04-1.80
 Immunosuppression 106 14 13.2 0.58 0.33-1.03 0.0 % 0.76 0.40-1.46
 Diabetes 1048 234 22.3 1.10 0.94-1.29 0.0 % 1.36 1.10-1.70
 Renal disease 588 129 21.9 1.08 0.88-1.32 48.2 % 1.23 0.95-1.59
 Neuromuscular 167 52 31.1 0.93 0.68-1.26 38.9 % 1.13 0.80-1.58
 Neoplasm (active) 301 63 20.9 1.01 0.76-1.35 55.6 % 1.29 0.92-1.81
 Liver disease 200 33 16.5 0.76 0.52-1.11 50.8 % 0.79 0.52-1.21
 Autoimmune disease 161 39 24.2 1.22 0.85-1.77 0.0 % 1.44 0.95-2.18
 Obesee 1620 337 20.8 1.0 0.9-1.2 0.0 % 0.87 0.73-1.03
Pregnancyf 298 160 53.7 3.45 2.23-5.34 0.0 % 2.08 1.43-3.03
 Associated comorbidity 38 26 68.4 7.07 3.09-16.18 0.0 % 4.29 2.65-6.94
 No comorbidity 260 126 48.5 3.05 2.08-4.47 0.0 % 1.80 1.22-2.66
  1. aStrains considered: A(H3N2), A(H1N1)pdm09 and B/Yamagata
  2. bMinimal sufficient adjustment sets for estimating the exposure or risk factor effect on the risk of admission with influenza vs. all included admissions without underlying conditions or pregnant
  3. cFemale or female non-pregnant vs. male. aORs were adjusted for age, occupational social class group, underlying comorbidity, obesity, influenza vaccination, time to swab, calendar time, and site as a clustering factor
  4. dOne or more underlying conditions or individual comorbidities vs. no comorbidity. aORs were adjusted for sex, occupational social class group, obesity, influenza vaccination, time to swab, calendar time, and site as a clustering factor
  5. eaOR adjusted for sex, age, occupational social class group, influenza vaccination, time to swab, calendar time, and site as a clustering factor
  6. fWomen 15-45 years of age included in Moscow, St. Petersburg, Czech Republic, Turkey and Valencia. aOR adjusted for smoking habits, time to swab, calendar time, comorbidity, and site as a clustering factor. For results stratified by comorbidity, aORs were adjusted by the same covariates and were estimated taking into account the interaction between pregnancy and comorbidity