Table 4 Univariate analysis for Risk factors of severe CAP among patients stratified by ages

Gender (male)

1.11 [1.00–1.23]

0.0547

0.82 [0.66–1.03]

0.0891

0.80 [0.63–1.00]

0.0476

0.97 [0.78–1.19]

0.7588

Rural resident

1.86 [1.69–2.05]

< 0.0001

1.55 [1.25–1.93]

< 0.0001

1.90 [1.52–2.37]

< 0.0001

2.44 [1.96–3.03]

< 0.0001

Premature birth

3.56 [3.15–4.03]

< 0.0001

2.73 [2.06–3.63]

< 0.0001

2.21 [1.58–3.09]

< 0.0001

1.48 [1.02–2.16]

0.0403

LBW

4.00 [3.52–4.54]

< 0.0001

3.90 [2.99–5.10]

< 0.0001

1.97 [1.40–2.78]

< 0.0001

1.30 [0.87–1.95]

0.1961

Unhealthy parents

1.65 [1.41–1.92]

< 0.0001

1.74 [1.22–2.47]

0.0023

1.63 [1.13–2.36]

0.0094

1.41 [0.97–2.05]

0.0683

Feeding

1.44 [1.35–1.53]

< 0.0001

1.41 [1.24–1.61]

< 0.0001

1.13 [0.98–1.30]

0.0967

1.11 [0.97–1.28]

0.1360

CHD

4.69 [4.22–5.21]

< 0.0001

5.75 [4.42–7.48]

< 0.0001

5.62 [3.96–7.98]

< 0.0001

3.62 [2.22–5.92]

< 0.0001

History of pneumonia

2.57 [2.27–2.91]

< 0.0001

2.76 [2.18–3.51]

< 0.0001

2.11 [1.60–2.77]

< 0.0001

1.55 [1.16–2.06]

0.0027

History of jaundice

2.24 [1.86–2.70]

< 0.0001

3.18 [1.93–5.25]

< 0.0001

1.91 [0.83–4.37]

0.1258

1.68 [0.64–4.37]

0.2897

Cough

0.36 [0.32–0.41]

< 0.0001

0.27 [0.21–0.36]

< 0.0001

0.52 [0.39–0.70]

< 0.0001

0.38 [0.29–0.51]

< 0.0001

Fever

1.09 [0.96–1.23]

0.1944

1.05 [0.84–1.30]

0.678

0.89 [0.71–1.13]

0.347

0.82 [0.65–1.03]

0.0938

Wheezing

1.01 [0.88–1.16]

0.903

1.06 [0.83–1.36]

0.6419

2.33 [1.79–3.03]

< 0.0001

3.36 [2.53–4.46]

< 0.0001

Cyanosis

13.01 [9.88–17.13]

< 0.0001

55.49 [16.35–188.37]

< 0.0001

43.68 [12.58–151.63]

< 0.0001

28.23 [2.93–272.06]

0.0039

Dyspnea

35.08 [15.16–81.15]

< 0.0001

103.08 [13.39–793.81]

< 0.0001

0.52 [0.00-I]

0.9651

47.16 [5.51–403.78]

0.0004

Abnormal chest X-ray

7.70 [6.31–9.40]

< 0.0001

15.81 [10.90–22.94]

< 0.0001

10.39 [7.07–15.27]

< 0.0001

7.37 [5.45–9.98]

< 0.0001

Abnormal WBC

2.43 [1.98–2.98]

< 0.0001

2.01 [1.32–3.05]

0.2253

1.29 [0.85–1.95]

0.2253

1.27 [0.87–1.86]

0.2155

Abnormal Neu

2.48 [2.16–2.85]

< 0.0001

2.99 [2.21–4.06]

< 0.0001

3.20 [2.40–4.25]

< 0.0001

3.22 [2.51–4.13]

< 0.0001

Abnormal Lym

2.77 [2.40–3.18]

< 0.0001

3.93 [2.84–5.44]

< 0.0001

2.26 [1.63–3.13]

< 0.0001

5.27 [4.08–6.81]

< 0.0001

Abnormal Na

3.81 [3.22–4.49]

< 0.0001

5.26 [3.70–7.48]

< 0.0001

4.69 [3.36–6.55]

< 0.0001

4.12 [3.12–5.45]

< 0.0001

CRP > 6 mg/L

2.17 [1.85–2.56]

< 0.0001

1.76 [1.30–2.39]

0.0003

1.81 [1.37–2.40]

< 0.0001

1.83 [1.42–2.35]

< 0.0001

ESR > 10 mm/h

0.55 [0.29–1.03]

0.0613

0.90 [0.40–2.00]

0.7909

0.63 [0.35–1.13]

0.1230

0.80 [0.45–1.43]

0.4500

ALB< 35 g/L

5.57 [4.65–6.66]

< 0.0001

15.95 [9.9–25.69]

< 0.0001

11.67 [7.24–18.81]

< 0.0001

12.85 [8.93–18.50]

< 0.0001

ALT> 100 U/L

1.92 [1.51–2.45]

< 0.0001

3.44 [1.97–6.03]

< 0.0001

3.25 [1.85–5.71]

< 0.0001

8.43 [4.80–14.80]

< 0.0001

AST > 100 U/L

2.02 [1.62–2.51]

< 0.0001

5.82 [3.44–9.87]

< 0.0001

5.34 [3.20–8.89]

< 0.0001

12.66 [7.22–22.19]

< 0.0001

TBIL>17umol/L

1.61 [1.40–1.87]

< 0.0001

5.29 [2.19–12.77]

0.0002

18.34 [5.60–60.06]

< 0.0001

7.70 [4.33–13.68]

< 0.0001

SCR > 70umol/L

1.03 [0.66–1.61]

0.8935

2.48 [0.99–6.19]

0.0519

4.01 [1.60–10.04]

0.0030

5.11 [2.10–12.43]

0.0003

Proteinuria

4.94 [4.04–6.06]

< 0.0001

5.69 [4.01–8.07]

< 0.0001

3.47 [2.47–4.87]

< 0.0001

2.14 [1.64–2.78]

< 0.0001

RSV infection

1.59 [1.22–2.07]

0.0005

1.11 [0.63–1.96]

0.722

0.64 [0.30–1.36]

0.2463

0.81 [0.35–1.84]

0.6102