Study of some risk factors and C - reactive protein levels among patients with cardiovascular diseases

Objective : To study the effect of some risk factors like age, smoking and Diabetes mellitus (DM) among patients with certain cardiovascular diseases (Angina pectoris and Myocardial infarction), in addition to the assessment of the C-reactive protein (CRP) in the sera of those patients. Methodology: The study was carried out on (100) subjects who were hospitalized in the Iraqi Center of heart Diseases in Baghdad city and were suﬀering from Myocardial Infarc(cid:415)on (MI) (16) and Angina Pectoris (AP) (79) or from both (5) over a period from September 2009 to June 2010. The results of pa(cid:415)ents were compared with those of (30) healthy and age-matched individuals as a control group. Data were obtained from patients who were already diagnosed by specialists through the use of questionnaire forms including information about age, gender and smoking. Venous blood samples were collected from both the patients and control group to estimate the levels of blood glucose and C-reactive protein. Results: Sta(cid:415)s(cid:415)cal results showed that the majority of angina pa(cid:415)ents were males within the age group (51-60) years with significant differences between males and females. The study also demonstrated that the incidence of (MI) and (AP) was higher among non-smokers in comparison with smokers. The study indicated that the majority of patients with (MI) and (AP) were diabetic. Finally, the study showed that the levels of C-reactive protein among (MI) and (AP) patients were higher than its level among the control group with a highly significant difference. Recommendations : A large size of sample is recommended to be studied to confirm the results of this study. Study of other factors such as hypertension, body mass index and lipid profile may be of value.

Angina pectoris has a wide range of clinical expressions.The most often associated symptoms to angina are substernal chest pressure or tightening, frequently with radiating pain to the arms, shoulders or jaw.The symptoms may also be associated with shortness of breath, nausea or diaphoresis.Symptoms stem from inadequate oxygen delivery to myocardial tissue (2) .Classical symptoms of acute myocardial infarction include sudden chest pain, shortness of breath, nausea, vomiting, palpitations, sweating and anxiety (3) .Among the diagnostic tests available to detect heart muscle damage are an electrocardiogram (ECG), electrocardiography , and various blood tests (4) .C-Reactive protein (CRP) is a sensitive marker of systemic inflammation, and prospective data from population of apparently healthy men indicate that baseline levels predict risk of first myocardial infarction (5) .Specifically, among men free of prior cardiovascular disease participating in the physicians' health study, many studies recently reported that those with baseline levels of CRP in highest quartile had a three folds increase in risk of developing future MI compared with those with levels in the lowest quartile as such these data demonstrate that CRP is a marker of cardiovascular risk not only among those with static and unstable angina, elderly and selected high risk patients, but also among individuals with no current evidence of cardiovascular disease (6)(7)(8)(9)(10) .Therefore, in this study, we examined patients from Iraqi Center of Heart Diseases who were suffering from (MI&AP) or both to study some risk factors like age, smoking, diabetes as well as to assess CRP levels among them.Regarding to the effect of age on the incidence of disease, it was observed that there was no statistically significant difference among patients with (MI, AP and MI + AP) in relation with the distribu on of the ages of the control group (p>0.05).According to gender distribution.The results show that there was a highly significant difference (p<0.05) in the incidence of (MI) and(AP) disease among males (87.5%) and(81%) respectively when compared with the control group (46.7%).While, no significant difference was found in gender distribution between (MI and AP) group and control group (p>0.05).This table revealed that the percentage of non-smokers formed most of the studied patients (69%) when compared with smokers (31%), par cularly among AP pa ents (53%).The table also showed that there was a highly significant difference between cardiovascular diseases and control group (p<0.05).The effect of Diabetes Mellitus (DM) on induction of heart diseases was shown in table (5).It was clear from this table that there was a high frequency (60%) of diabe c pa ents among (MI and AP) patients.All three groups of patients demonstrated a highly significant variation with the control group concerning diabetes (p<0.05).

Table 5. Effect of Diabetes Mellitus on the frequencies of cardiovascular diseases
Create PDF files without this message by purchasing novaPDF printer (http://www.novapdf.com)Detection of C-reactive protein showed a high frequency of posi ve samples (80%) among ( MI & AP) group with a highly significant difference when compared with other groups.The same results were found in CRP levels among cardiovascular diseases when compared with the control group (p<0.05).

Discussion
Data of this study were obtained from a group of patients suffering from myocardial infarction and angina pectoris or both.The study depended on determining the effect of age, gender, diabetes, smoking on certain cardiovascular diseases as well as assessing the CRP values among them.
Regarding to gender distribution, the study reveals that most patients are males, with predominance of angina patients.A result that agrees with the collaborative study that found lower prevalence in women than men due to their metabolic differences, but we may attribute this finding to the fact that women usually refuse hospitalization (11)(12) .
The study demonstrates that the majority of pa ents are among the age group (51-60) years, which coincides with the findings a study states that the cause of most frequently complications such as diabetes, hypertension and cardiovascular diseases happens in this age group.However, our study reveals no significant variation between the ages of the studied patients and the control group (13) .
Data obtained from our results indicates that most patients are non-smokers.This result disagrees with a study that found increased cardiac events in smoker males.We may explain the present result to that not only smoking, but also several other risk factors cause cardiovascular diseases including hypertension, hyperlipidemia, obesity, exercise….etc,and that the patients may be smokers at past (14) .
The effect of diabetes mellitus on induction of heart diseases shows that most of patients are diabetic.However, this finding agrees with that of a study stated that hyperglycemia dependently increased infarct size and abolished protection afforded by ischemic preconditioning (15) , and studies that showed that hyperglycemia has proinflammatory reaction, which plays an important role in inducing the release of cytokines and associated with increased mortality from MI (16)(17) .
Results of CRP detection reveal high frequency positive samples among (MI) and (AP) group in comparison with the control group.A result which is confirmed by studies that reported that inflammatory markers such as CRP reflect the extent of myocardial necrosis and correlate with cardiac outcomes following acute myocardial infarction (18)(19)(20) .The present study shows that male pa ents aged (51-60) years have the highest prevalence of cardiovascular diseases due to most frequently complications of this age group and to metabolic differences between males and females.
Unfortunately, non-smoker cardiovascular patients are higher than smokers in our study, a result that may attribute the occurrence of such diseases to risk factors other than smoking including hypertension, hyperlipidemia or obesity.
Most of the patients in our study are diabetic because hyperglycemia has effect on induction of heart diseases.
Finally, the levels of C-Reactive protein are higher among cardiovascular patients due to the correlation of this inflammatory marker with cardiac necrosis.

Recommendations
This study has been performed on a number of cardiovascular patients to find out their correlation with some risk factors.Therefore, a large size of sample is recommended to be studied to confirm the results of this study.Study of other factors such as hypertension, body mass index and lipid profile may be of value.

A
prospective study was conducted at The Iraqi Center Of Heart Diseases on (100) recently diagnosed (16) myocardial infarc on (MI), (79) angina pectoris (AP) and (5) both (MI&AP) pa ents, compared with (30) healthy control group whose ages and sexes were nearly similar to the patient's group.For each patient and control, Electrocardiogram (ECG) was done, and medical examination by specialists in the center was made to confirm the diagnosis of each medical condition.Venous blood samples were obtained immediately after diagnosis from each patient to measure the levels of blood sugar and C-reactive protein.Blood sugar was measured by routine enzymatic kit method, while high sensitivity CRP was measured by latex test.In this assay, latex H Create PDF files without this message by purchasing novaPDF printer (http://www.novapdf.com)beads coated with mouse monoclonal antibodies bind CRP present in the serum sample and form agglutination. Data were analyzed statistically using Levene's test for quality of variances, analysis of variance (ANOVA) for quality means, least significant difference (LSD) for multiple comparisons after analysis of variance, and mean standard deviation, standard error 95% confidence intervals for population mean value as well as Fisher's exact tests by using the SPSS (version 10) program.

Table 1 .
Distribu on of 100 pa ents with MI + AP and 30 control subjects according to their demographic characteristics

Table 2 .
Distribution of the study and control groups according to their age

Table 2a .
Summary statistics for different study groups (Study-control) according to age factor

of coincidence Levene's Test for Equality of Variances t-test for Equality of Means
ANOVA : Analysis of variance

Table 2b .
Multiple comparisons of age groups among different groups

Table 6 .
Distribution of patients according to CRP positivity