COMPARISON OF COCKROFT-GAULT FORMULA AND CREATININE LEVEL IN RISK STRATIFICATION OF OUT-WARD PATIENTS WITH ARTERIAL HYPERTENSION

Introduction: Impaired renal function is an independent risk factor for cardiac events. For its evaluation is recommended to calculate glomerular filtration (GF) using Cockcroft-Gault formula. In ambulatory praxis is calculation of GF often underestimated, especially in patients with creatinine level in reference range. 
Method: We compared meaning of calculated GF and quartiles of creatinine (Q-CREA) in reference range (≤ 135 μmol/l) on consideration of  classic risk factors and absolute risk in pts with arterial hypertension (AH).
Results: In multicentric project were enrolled 558 out-ward pts (M-39.2%; F-60.8%) with AH (162.9±17.4/94.3±8.8 mm Hg) with CREA≤ 135 μmol/l. Calculated GF identified only 56.8% of pts  in 1.grade,  33.9% were in 2. grade, res. 8.1% in 3. grade of renal impairement (K/DOQI). Pts in 3.grade of K/DOQI  exhibited significantly higher absolute risk (acc. to SCORE) in comparison with 4Q-CREA : 6.20 vs. 6.08 (p<0.05). K/DOQI distribution shown higher statistical  between-subjects contrasts of classic risk factors in comparison with Q-CREA distribution (Tabs 1 and 2).

Table1. Distribution of classic risk factors acc. to Q-CREA                                                              

                         Age     SBP/ DBP      LDL         HDL         TG
Q-CREA            [yrs]    [mmHg]          [mmol/l]    [mmol/l]    [mmol/l]
1                       62.5    161.2/ 92.1    3.29         1.40        1.95
2                       61.8    163.6/ 94.6    3.31         1.39        2.10
3                       61.7    163.1/ 95.8    3.34         1.33        2.35
4                       61.7    163.5/ 94.9    3.44         1.34        2.23
      
Signif                NS       NS   0.02       NS            NS         0.001

Table 2. Distribution of classic risk factors acc. to K/DOQI.
                        Age      SBP/ DBP      LDL          HDL         TG
K/DOQI            [yrs]     [mmHg]          [mmol/l]     [mmol/l]    [mmol/l]
1                      57.1     161.9/ 95.0    3.34         1.33         2.21
2                      66.9     163.6/ 93.4    3.44         1.43         2.13
3                      75.3     168.0/ 94.0    3.13         1.39         1.92
      
Signif               0.001    0.03   0.04   0.08 - NS   0.02        NS

Conclusion: Use of Cockroft-Gault formula in stratification of out-ward patients with arterial hypertension provide more relevant clinical information in comparison with consideration of creatinine in reference range.