The Study Of Heart Function, Anemia And Renal Function In Inpatients With Chronic Heart Failure

ObjectiveThe aim of this study was to survey the prevalence of anaemia in inpatients with chronic heart failure (CHF) and assess the relationship among heart function, anaemia and renal function in these patients with a retrospective analysis.MethodsInpatients with CHF in our cardiovascular department between April 1st 2004 and April 1st 2006 were included in this retrospective analysis. The data including laboratory measurements, echocardiographic parameters and so on of patients to be selected were collected. Haemoglobin (Hb) values (male) <120g/L or <110g/L(female) was defined as anaemia. The prevalence of anaemia in the patients of CHF was calculated. The patients were divided into anaemia and non-anaemia group, whose symptoms of heart failure, renal function and laboratory measurements were compared. Heart function were evaluated with the New York Heart Association (NYHA) class which was divided intoⅠtoⅣclass. The glomerular filtration rate (GFR) was estimated by simplified MDRD formula. The renal function was divided into five stages according to K/DOQI Clinical Practice Guidelines for Nutrition in Chronic Renal Failure. Measurement data with or without Gaussian distribution was expressed with (x|-)±s or median respectively. In addition, a logistic regression analysis was performed on the influence of different risk factors on anaemia. The relationship among heart function, anaemia and renal function was also analyzed.Results1. The prevalence of Anaemia in inpatients with CHF was 10.4%(121/1159). Furthermore, the prevalence of anaemia of the patients with CHF in NYHAⅠ,Ⅱ,ⅢandⅣwas 3.4%, 6.5%, 19.8% and 43.6% respectively (P<0.001).2. The left ventricular ejection fraction (LVEF) in anaemia group (61%) was lower than those in non-anaemia group (68%) (P<0.001). The median NYHA class in anaemia group (classⅢ) was higher than those in non-anaemia group (classⅡ) (P<0.001). The proportion of patient with NYHAⅢ/Ⅳwas 58.6% in the anaemia group, but the proportion was only 21.3% in the non-anaemia group(P<0.001). The above data showed that the heart function in patients with anaemia was lower than those without anaemia.3. The median of GFR of the patients with CHF in NYHAⅠ,Ⅱ,ⅢandⅣwas 80.4ml/min/1.73m~2,76.3ml/min/1.73m~2,66.6ml/min/1.73m~2 and 65.7 ml/min/1.73m~2 respectively (P<0.001).The blood serum creatinine level in anaemia group (99umol/L) was higher than those in non-anaemia group (86umol/L) (P<0.001). The median of GFR in anaemia group (59.83 ml/min/1.73m~2) was lower than those in non-anaemia (74.98ml/min/1.73m~2) (P<0.001). The proportion of patients with GFR<60 ml/min/1.73m~2 was 50.4% in the anaemia group, but the proportion was only 18.7% in the non-anaemia group (P<0.001). The above data showed that the renal function in patients with anaemia was lower than those without anaemia.4. The median Hb of all patients with CHF in NYHAⅠ,Ⅱ,ⅢandⅣwas 140.5g/L,135.0g/L,133.0g/L and 117.0g/L respectively (P<0.001). The Hb level of the patients in the group (241 patients) with normal renal function with CHF in NYHAⅠ,ⅡandⅢ/Ⅳwas 141.43±13.81g/L,134.96±15.97g/L and 129.12±13.84g/L respectively (P<0.01). Out of the parameters evaluated as independent risk factor, NYHA class had the greatest effect on anaemia, with a relative risk (RR) of 14.07 and 95% confidence interval (CI) of 5.37 to 36.9 in patients with NYHAⅣ(P<0.01).5. The median haemoglobin of the patients in renal function stage 1, 2, 3 and 4/5 was 135.0 g/L,137.0 g/L,131.0 g/L and 107.5 g/L respectively (P<0.001). Out of the parameters evaluated as independent risk factor, renal function stage had obvious effect on anaemia with an RR of 1.81 and 95% CI of 1.81 to 2.75 (P<0.01).ConclusionsThe prevalence of anaemia in inpatients with CHF is 10.4% in the data. Both heart function and renal function in patients with anaemia are lower than those without anaemia. Both CHF and chronic renal failure (CRF) are important risk factors for anaemia in patients with heart failure. Furthermore, the lower of NYHA heart function class in the patients with CHF, the worse of renal function in those patients is found. In a word, CHF, CRF and anaemia form a vicious circle.