Table 3.
Correlates of RSV infection among children less than five years of age admitted with acute respiratory illness at Aga Khan University Hospital Karachi, Pakistan (Aug 2009-Jul 2012)
| Baseline characteristics | Crude RR (95% CI) | P value for Crude RR | Adj RR (95% CI) | P value for Adj RR |
|---|---|---|---|---|
| Age in months | 0.97 (0.96-0.99) | <0.001 | - | - |
| Age groups (months) | ||||
| 0-2 | 1.84 (1.28-2.64) | 1.81 (1.17-2.81) | ||
| 3-5 | 1.48 (1.03-2.14) | 0.006 | 1.51 (0.99-2.32) | 0.036 |
| 6-11 | 1.16 (0.81-1.65) | 1.15 (0.77-1.72) | ||
| 12-60 | 1 | 1 | ||
| Male | 0.88 (0.67-1.16) | 0.366 | - | - |
| Birth weight (kg) | 0.89 (0.73-1.09) | 0.264 | - | - |
| Born early | 0.99 (0.72-1.35) | 0.952 | - | - |
| Enrollment period (Seasonality): | ||||
| Jan-March | 1 | 1 | ||
| April-June | 1.04 (0.59-1.82) | <0.001 | 1.03 (0.56-1.89) | <0.001 |
| July-Sep | 2.77 (1.90-4.03) | 3.56 (2.33-5.43) | ||
| Oct-Dec | 2.29 (1.56-3.38) | 2.89 (1.88-4.44) | ||
| Duration of breast feeding (months) | 0.99 (0.96-1.02) | 0.566 | - | - |
| Day care attendance | 1.09 (0.59-2.00) | 0.777 | - | - |
| Smokers in the house | 1.10 (0.83-1.49) | 0.489 | - | - |
| Number of household members | 1.01 (0.98-1.03) | 0.647 | - | - |
| Crowding index (household members/# bedrooms) | 0.94 (0.84-1.06) | 0.312 | - | - |
|
Clinical features | ||||
| fever | 0.79 (0.60-1.05) | 0.101 | - | - |
| Cough | 1.26 (0.81-1.93) | 0.303 | - | - |
| wheezing/noisy breathing | 1.02 (0.99-1.05) | 0.245 | - | - |
| poor appetite | 0.98 (0.86-1.12) | 0.780 | - | - |
| shortness of breath | 1.14 (0.98-1.33) | 0.081 | - | - |
| ear ache | 0.93 (0.81-1.08) | 0.357 | - | - |
| sore throat | 1.01 (0.94-1.07) | 0.974 | - | - |
| Post-tussive emesis | 1.05 (1.01-1.09) | 0.037 | 1.54 (1.12-2.11) | 0.008 |
| nasal congestion | 1.05 (1.01-1.10) | 0.029 | - | - |
|
Hospital course | ||||
| Intubated | 1.55 (0.76-3.13) | 0.225 | 3.97 (1.59-9.91) | 0.003 |
| ICU admission or transfer | 1.14 (0.58-2.22) | 0.705 | - | - |
| Length of hospital stay (days) | 1.01 (0.97-1.04) | 0.667 | - | - |
| Died during hospitalization | 0.46 (0.12-1.87) | 0.280 | - | - |
|
Discharge diagnosis | ||||
| URI | 0.67 (0.42-1.06) | 0.09 | - | - |
| Asthma | 0.78 (0.53-1.14) | 0.20 | - | - |
| Pneumonia | 1.06 (0.81-1.38) | 0.69 | - | - |
| Bronchiolitis | 1.70 (1.30-2.22) | <0.001 | 1.63 (1.16-2.27) | 0.004 |
Risk ratio based on log binomial regression analysis. Outcome variable: RT-PCR status for RSV=1 for positive and 0 for negative. Variables with p values less than 0.30 at the univariate level were taken forward to the multivariables regression model.