Table 2.
Odds ratios for hospitalization or ICU admission/death for various potential risk factors
| Variables | Odds Ratio (95% confidence interval) for different comparisons | |||
|---|---|---|---|---|
| Hospitalized (321)/ Non‐hospitalized (395) | ICU or death (62)/ Hospitalized non‐severe (259) | |||
| Univariate | Multivariable* | Univariate | Multivariable* | |
| Female gender | 0·9 (0·6–1·2) | 1·2 (0·7–1·9) | 2·06 (1·2–3·7) | 2·1 (0·9–5·1) |
| Age | ||||
| <5 years | 5·8 (3·2–10·4) | 5·5 (2·1–14·3) | 0·5 (0·2–1·7) | 0·5 (0·1–1·9) |
| 5–19 years | Reference | Reference | Reference | Reference |
| 20–34 years | 0·9 (0·6–1·4) | 2·6 (0·5–13·3) | 2·6 (1·0–6·6) | 2·1 (0·2–24·2) |
| 35–49 years | 1·5 (1·0–2·4) | 4·5 (0·9–23·2) | 3·6 (1·5–8·4) | 1·7 (0·2–18·3) |
| 50–59 years | 1·7 (1·0–2·7) | 4·3 (0·8–23·8) | 1·5 (0·5–4·2) | 0·6 (0·04–7·5) |
| 60 years and older | 3·7 (2·0–6·8) | 2·2 (0·7–6·5) | 2·4 (0·9–6·3) | 1·1 (0·2–7·2) |
| Education | ||||
| High school not completed | 2·5 (1·5–4·0) | 1·3 (0·7–2·4) | 2·3 (0·9–6·3) | 1·5 (0·4–4·9) |
| Non‐university certificate/diploma | 1·5 (1·0–2·1) | 1·2 (0·7–1·8) | 1·9 (0·8–4·6) | 1·4 (0·5–4·1) |
| University degree | Reference | Reference | Reference | Reference |
| Health care worker | 0·1 (0·1–0·3) | 0·2 (0·1–0·4) | 2·8 (0·7–11·7) | 4·3 (0·8–24·7) |
| Smoking | 1·9 (1·2–2·9) | 1·3 (0·7–2·2) | 0·9 (0·4–2·0) | 0·7 (0·3–1·7) |
| Seasonal influenza vaccination in 2008–2009 | 1·3 (0·9–1·8) | 1·0 (0·6–1·5) | 1·2 (0·6–2·1) | 0·8 (0·4–1·8) |
| Consultation, days after symptom onset | ||||
| 0–1 days | 1·5 (1·0–2·1) | 1·5 (0·9–2·4) | 1·1 (0·6–2·3) | 1·7 (0·7–3·9) |
| 2–4 days | Reference | Reference | Reference | Reference |
| 5 days or more | 1·8 (1·2–2·6) | 1·9 (1·2–2·9) | 1·3 (0·7–2·6) | 1·5 (0·7–3·4) |
| Antiviral use before hospitalization | 0·9 (0·6–1·3) | 1·0 (0·6–1·6) | 0·4 (0·2–1·1) | 0·3 (0·1–0·8) |
| Pregnancy (ref: no, female 14–49 years) | 1·9 (0·8–4·9) | 2·4 (0·8–7·3) | 0·2 (0·02–1·7) | 0·2 (0·02–1·8) |
| Underlying medical conditions | ||||
| At least one** | 4·5 (3·2–6·3) | 4·9 (3·2–7·3) | 1·6 (0·9–2·9) | 1·5 (0·8–2·9) |
| Cardiac | 5·6 (2·8–11·4) | 2·7 (1·1–6·5) | 1·6 (0·8–3·5) | 2·1 (0·8–6·1) |
| Diabetes | 4·3 (2·2–8·4) | 2·7 (1·1–6·5) | 1·9 (0·9–4·0) | 1·4 (0·5–3·8) |
| Pulmonary | 3·9 (2·1–7·2) | 2·5 (1·2–5·4) | 1·8 (0·8–3·7) | 1·7 (0·8–4·3) |
| Asthma | 2·6 (1·6–4·0) | 2·8 (1·6–4·7) | 0·7 (0·3–1·5) | 0·5 (0·3–1·3) |
| Immune‐suppression | 1·8 (0·99–3·4) | 0·8 (0·4–1·9) | 2·4 (1·0–5·7) | 3·0 (0·9–9·7) |
| Neuromuscular | 24·8 (3·3–185·7) | 22·2 (2·6–186·0) | 1·1 (0·4–3·5) | 0·9 (0·2–3·6) |
| Renal | 5·8 (1·9–17·3) | 4·8 (1·3–17·7) | 0·8 (0·2–3·0) | 0·4 (0·08–2·0) |
| Other | 6·1 (2·7–14·1) | 5·6 (2·0–15·7) | 2·1 (0·9–4·6) | 1·2 (0·4–3·4) |
| Obesity (BMI ≥30) | 2·2 (1·4–3·0) | 1·3 (0·8–2·0) | 1·1 (0·6–2·0) | 1·0 (0·5–2·3) |
| BMI ≥40 (only in adults)*** | 3·1 (1·2–8·4) | 2·0 (0·6–6·2) | 0·9 (0·2–3·3) | 0·4 (0·09–2·0) |
BMI, body mass index; ICU, intensive care unit.
In bold, P < 0·05.
*Adjusted for all variables listed in the table, excepting underlying condition, at least one; and BMI defined as ≥40.
**For this variable, a separate model was constructed (multivariable adjusted for age, gender, obesity, being a health care worker, seasonal influenza vaccination, smoking, delay in consultation, antiviral use before admission, pregnancy, and education).
***For this variable, a separate model was constructed only in adults (multivariable adjusted for age, gender, underlying condition, being a health care worker, seasonal influenza vaccination, smoking, delay in consultation, antiviral use before admission, pregnancy, and education).