Table 4 . HR of 305 CHF readmission according to SES quartiles and risk factors with Cox regression, crude and adjusted model, Tehran, 2010–1 .
| Variables | Crude model | Adjusted model | ||
| HR (95% CI) | P | HR (95% CI) | P | |
| SES variable* | ||||
| 4th quartile (the highest, ref) | Ref | - | Ref | - |
| 3rd quartile | 1.63 (0.87-3.04) | 0.124 | 1.05 (0.57-1.93) | 0.852 |
| 2nd quartile | 7.78 (4.39-13.70) | <0.001 | 2.84 (1.62-4.98) | <0.001 |
| 1stquartile (the lowest) | 9.57 (5.55-16.50) | <0.001 | 2.66 (1.51-4.66) | <0.001 |
| Age | ||||
| <75 years | Ref | - | - | - |
| >75 years | 1.31 (0.94-1.79) | 0. 245 | - | - |
| Female gender* | 1.32 (0.97-1.79) | 0.073 | 1.14 (0.81-1.62) | 0.433 |
| Single marital status* | 1.65 (1.18-2.30) | <0.001 | 1.12 (0.80-1.59) | 0.485 |
| BMI | ||||
| <25 (normal) (ref) | Ref | - | - | - |
| ≥25 (overweight/obese) | 1.16 (0.86-1.57) | 0.325 | - | - |
| Ejection fraction <40%* | 6.03 (3.20-11.09) | <0.001 | 3.03 (1.74-5.28) | <0.001 |
| Current smoker* | 1.50 (1.11-2.02) | 0.007 | 1.11 (0.79-1.55) | 0.524 |
| Poor adherence | ||||
| Drug* | 6.37 (4.41-9.21) | <0.001 | 2.86 (2.01-4.07) | <0.001 |
| Physical activity* | 5.66 (3.35-9.56) | <0.001 | 2.35 (1.41-3.93) | <0.001 |
| Diet | 1.20 (0.87-1.65) | 0.264 | - | - |
| Positive history | ||||
| Family history of CHD | 1.13 (0.84-1.51) | 0.402 | - | - |
| Surgical/non-surgical cardiac interventions | 1.02 (0.76-1.38) | 0.846 | - | - |
| Comorbidity | ||||
| Hypertension* | 4.12 (2.38-7.13) | <0.001 | 1.63 (1.04-2.57) | 0.033 |
| Diabetes mellitus* | 1.65 (1.22-2.24) | 0.001 | 1.01 (0.74-1.38) | 0.935 |
| Dyslipidemia | 1.48 (0.75-2.91) | 0.249 | - | - |
HR= Hazard Ratio; CHF= Congestive Heart Failure; SES= Socio-economic Status; CI= confidence interval; BMI= Body mass index; CHD= Coronary Heart Disease
*These variables had p-value of less than 0.20 in crude analysis and only these variables entered to adjusted analysis model.