Prevalence of Cardiovascular Risk Factors in Chronic Hemodialysis Patients at the University Hospital Center of Point G in Bamako, Mali

Introduction: A cardiovascular risk factor (FDRCV) is defined as a physiological, pathological or environmental attribute or characteristic that results in an increased likelihood of developing cardiovascular disease in the individual in whom it is detected. The objective of this study was to determine the prevalence of cardiovascular risk factors in hemodialysis patients on hemodialysis at the University Hospital of Point G. Patients and Methods: This was a cross-sectional descriptive study with prospective data collection from March 3, 2009 to March 5, 2010 (13 months). Included were all patients with end-stage renal disease (ESRD) receiving chronic hemodialysis in the Nephrology and Hemodialysis Department of the University Hospital of Point G during the study period. Results: Eighty-eight patients were enrolled. The M/F sex ratio was 1.26. The mean age was 41.32 years with extremes of 17 and 81 years. The classic cardiovascular risk factors in order of frequency were: hypertension (90.9%), sedentary lifestyle (71.6%), male sex (54.5%), age ≥ 55 years (21.6%), obesity (13.6%), diabetes (8%), tobacco (8%), alcohol (3.4%). Cardiovascular risk factors related to CKD were: anemia (98.9%), phosphocalcic disorders (85.2%), arteriovenous fistula (AVF) (80%), lipid abnormalities (36.5%), hydrosodium inflation (29.5%). Predominant cardiovascular complications were hypertensive heart disease (62.5%), acute pulmonary oedema (APO) (50%), rhythm disorders (23.9%), coronary insufficiency (18.2%). The mortality rate was 17%. Conclusion: Cardiovascular risk factors are frequent in chronic hemodialysis. They contribute to the excess mortality of these patients. Adequate management of these risk factors can slow down serious cardiovascular complications and reduce the risk of mortality in this fragile population.


Introduction
A cardiovascular risk factor (FDRCV) is defined as a physiological, pathological or environmental attribute or characteristic that results in an increased likelihood of developing cardiovascular disease in the individual in whom it is detected [1]. FDRCV in hemodialysis patients are multiple and varied. They associate anemia, hydrosodium inflation, age, male sex, phosphocalcic disorders responsible for cardiac and vascular calcifications, lipid abnormalities, arteriovenous fistula (AVF), aluminium poisoning, but also hyperhomocysteinemia and coagulation disorders [1]. There are other so-called classic or global cardiovascular risk factors that patients with chronic renal failure share with the general population, mainly high blood pressure (hypertension), diabetes, alcohol, tobacco and a sedentary lifestyle. Cardiovascular diseases, whose prevalence in patients with end-stage renal disease (ESRD) is ten to thirty times higher than in the general population, are the leading cause of mortality [1]. Left ventricular hypertrophy (LVH), heart failure and atherosclerosis are responsible for cardiovascular morbidity and mortality [1]. As traditional factors are insufficient to explain their high cardiovascular morbidity and mortality, factors related to chronic kidney disease (CKD) and its treatment have been discussed. These include proteinuria, hydroelectrolyte disorders, anemia, increased lipoprotein (a) (Lp (a)) and homocysteine, microinflammatory status and increased thrombogenic factors [1]. Cardiovascular complications (heart failure, sudden death, myocardial infarction (MI), stroke, peripheral arteritis, mesenteric infarction) account for 50% of the causes of death in hemodialysis [2]. The association of these complications with anemia aggravates the already precarious functional status and quality of life of dialysis patients [3].
The objective of this study was to determine the prevalence of cardiovascular risk factors in hemodialysis patients on hemodialysis at the University Hospital Center (UHC) of Point G.

Patients and Methods
This was a cross-sectional descriptive study with prospective data collection, which was conducted over a 13-month period from 3 March 2009 to 5 March 2010. It involved chronic ESRD patients receiving chronic haemodialysis in the Nephrology and Haemodialysis Department of the UHC of Point G during the Open Journal of Nephrology study period. Sociodemographic data (age, sex, occupation) and clinical data (history, cardiovascular risk factors) were collected by a comprehensive clinical examination of all patients. The cardiovascular risk factors studied were:  Classic cardiovascular risk factors:  High blood pressure (HBP): It is defined by a systolic blood pressure (SBP) greater than or equal to 140 mmHg and/or a diastolic blood pressure (DBP) greater than or equal to 90 mmHg at the doctor's office.  Smoking: Defined as the chronic, addictive intoxication of the body by tobacco.  Sedentary lifestyle: Sedentary lifestyle was defined as a lack of minimum physical activity that meets the needs of the human body, i.e. less than 150 minutes per week according to the ESC.  Diabetes: According to the WHO, diabetes is defined by a polyuro-polydipsia syndrome and fasting plasma glucose ≥ 1.26g /l twice (7 mmol/l) or random blood glucose (venous plasma) ≥ 2g /l (11.1 mmol/l) or blood glucose on venous plasma at the second hour of an orally induced hyperglycaemia ≥ 2g /l (11.1 mmol/l).  Alcoholism: It is a disease related to chronic abuse of alcoholic beverages, with alcohol dependence (more than 3 glasses in men and more than 2 glasses in women).  Obesity: It is defined by a body mass index (BMI = Weight (Kg)/Height (m 2 )) > 30 kg/m 2 .  Male sex:  Age over 55 years:  Cardiovascular risk factors related to CKD:  Anemia: Defined as a decrease in circulating hemoglobin mass with hemoglobin levels < 13 g/dl in men; <12 g/dl in women.  Hydrosodic inflation: It is defined as excess weight compared to the ideal weight (dry weight).  Phosphocalcic metabolism disorders: they classically associate hypocalcemia, hyperphosphatemia with a phosphocalcic product greater than 5.6 mmol 2 /l 2 and hyperparathyroidism (PTH > 9 times the upper limit of the laboratory standard).  Lipid abnormalities: Associated with a decrease in HDL cholesterol < 0.6 g/L, an increase in LDL cholesterol > 1.6 g/L and triglycerides > 1.5 g/L, a decrease in apolipoproteins AI and AII and an increase in apolipoprotein B and (a) (L(a)). apolipoproteins were not evaluated in our series.  A.V.F.: An arteriovenous fistula is a surgically made neo-circulation characterized by low arterial resistance and increased venous return. The duration of illness (ESRD/CAD), radiological investigations, few more bio physiological parameters also added to identify the risk.
Each patient in the series was given an individual follow-up sheet with systematic recording of sociodemographic, clinical and para-clinical data.
Data entry and analysis was performed on SPSS12.0. The statistical test used was Pearson Chi-square with p < 0.05 as a significant value.
Verbal informed consent was obtained from patients after explanation of the purpose of the study.

Results
We rounded up 88 patients.     Headache, fever and chills were the most common symptoms encountered in per dialysis. Open Journal of Nephrology

Discussion
Limitations of the study: Patients whose records were incomplete or unusable due to a lack of financial means to perform radiological and biological explorations, and the lack of consent of some, contributed to the reduction of our sample size.
Our study involved 88 chronic hemodialysis patients. In contrast, all of the FDRCVs specific to the related to chronic end-stage renal disease (ESRD) were present in all age groups.
Males not only had all the classic FDRCVs, but also had a relationship with smoking (P = 0.039). In contrast, all of the CKD-specific FDRCVs were present in both sexes. Obesity was a risk factor for thrombophlebitis (p = 0.028). Diabetes was a risk factor for lower limb arterial occlusive disease (LAOD) (P = 0.0001). Anemia was a risk factor for AVF thrombosis (P = 0.021) and pulmonary embolism (P = 0.010). Lipid abnormalities (P = 0.049) and male sex (P = 0.047) were risk factors for hypertensive cardiomyopathy. AVF was a risk factor for cardiac arrest (P = 0.001) and rhythm disorders (P = 0.029). Cardiac arrest was not observed with intradialysis. Pericarditis and mesenteric infarction were not observed during interdialysis follow-up, but hypertensive heart disease (62.5%) followed by PAO (50%) in agreement with the other authors [4]. This can be explained by the high frequency of hypertension (90.9%) in our series and the failure to comply strictly with the prescribed hygieno-dietary measures. The Open Journal of Nephrology mortality rate was 17%, 60% of which was due to cardiovascular causes. The mortality rate was 26.6% in Kitoune [10], 29% in Cissé [6] and 36% in Kane A. [14]. All these authors reported the cardiovascular predominance of the causes of death as reported in the literature [1] [8].

Conclusion
Cardiovascular risk factors are common in chronic hemodialysis. They contribute to the excess mortality of these patients. Proper management of these risk factors can slow down serious cardiovascular complications and reduce the risk of mortality in this fragile population.

Conflicts of Interest
None.