Association between peripheral arterial disease and creactive protein in the japanese-brazilian population

Abstracts

OBJECTIVE:

To evaluate the relationship between peripheral arterial disease and elevated levels of C-reactive protein in the Japanese-Brazilian population of high cardiovascular risk.

METHODS:

We conducted a cross-sectional study derived from a population-based study on the prevalence of diabetes and associated diseases in the Japanese-Brazilian population. One thousand, three hundred and thirty individuals aged e" 30 underwent clinical and laboratory examination, including measurement of ultrasensitive C-reactive protein. The diagnosis of peripheral arterial disease was performed by calculating the ankle-brachial index. We considered with peripheral arterial disease patients who had ankle-brachial index d" 0.9. After applying the exclusion criteria, 1,038 subjects completed the study.

RESULTS:

The mean age of the population was 56.8 years; 46% were male. The prevalence of peripheral arterial disease was 21%, with no difference between genders. Data analysis showed no association between peripheral arterial disease and ultrasensitive C-reactive protein. Patients with ankle-brachial index d" 0.70 showed higher values of ultrasensitive C-reactive protein and worse cardiometabolic profile. We found a positive independent association of peripheral arterial disease with hypertension and smoking.

CONCLUSION:

The association between low levels of ankle-brachial index and elevated levels of ultrasensitive C-reactive protein may suggest a relationship of gravity, aiding in the mapping of high-risk patients.

Peripheral arterial disease; C-reactive protein; Atherosclerosis; Homocysteine

OBJETIVO:

avaliar a relação entre a doença arterial obstrutiva periférica e níveis elevados de proteína C-reativa em população nipo-brasileira de alto risco cardiovascular.

MÉTODOS:

estudo transversal derivado de estudo de base populacional sobre a prevalência de diabetes e doenças associadas em população nipo-brasileira. Mil trezentos e trinta indivíduos com idade >30 foram submetidos a exame clínico e laboratorial, incluindo a dosagem da proteína C-reativa ultrassensível. O diagnóstico da doença arterial obstrutiva periférica foi realizado através do cálculo do índice tornozelo-braço. Foram considerados portadores de doença arterial obstrutiva periférica os pacientes que apresentaram índice tornozelo-braço <0,9. Após aplicação dos critérios de exclusão, 1038 indivíduos completaram o estudo.

RESULTADOS:

a média de idade da população foi 56,8 anos, 46% pertencentes ao sexo masculino. A prevalência da doença arterial obstrutiva periférica foi 21%, sem diferença entre os sexos. A análise dos dados não mostrou associação entre doença arterial obstrutiva periférica e proteína C-reativa ultrassensível. Os pacientes com índice tornozelo-braço <0,70 apresentaram valores mais elevados de proteína C-reativa ultrassensível e o pior perfil cardiometabólico. Encontramos associação positiva e independente da doença arterial obstrutiva periférica com hipertensão arterial e tabagismo. .

CONCLUSÃO:

a associação encontrada entre valores baixos de índice tornozelo-braço e níveis elevados de proteína C-reativa ultrassensível pode sugerir uma relação de gravidade auxiliando mapeamento dos pacientes de maior risco.

Doença arterial periférica; Proteína C-reativa; Aterosclerose; Homocisteina

INTRODUCTION

Despite changes in lifestyle and the growing therapeutic arsenal, cardiovascular diseases remain the leading cause of morbidity and mortality, especially in emerging developed countries. Twenty-year data from the Ministry of Health on the Health System showed that cardiovascular diseases are the leading cause of death in Brazil for both genders. In 2006, they accounted for 29.4% of deaths in the country, while neoplasia caused 15.1% ¹.

Cardiovascular diseases arise by large from the atherosclerotic process, so the study and understanding of new risk factors for atherosclerosis are needed to identify individuals at risk and also for the development of new therapeutic strategies. Peripheral arterial atherosclerotic disease is increasingly prevalent in modern society due in part to the increase in life expectancy, affecting 202 million people worldwide in 2010. During the last decade there was a 28.7% increase in the prevalence of the disease in countries of low and middle income per capita, and 13.1% in high-income ones ².

The pathophysiology of atherosclerosis is complex and multifactorial. The initial change in this process is endothelial dysfunction resulting from various factors, such as hypertension, diabetes mellitus, hypercholesterolemia, and smoking. During all phases of the atherosclerotic process there is release of cytokines, among them interleukin-6 (IL6), which is primarily responsible for the hepatic stimulation for the release of C-reactive protein (CRP), the main acute phase protein in the inflammation process ^{3 , 4}.

Thus, atherosclerosis is regarded as a dynamic and progressive disease, arising from the combination of endothelial dysfunction and inflammation. Endothelial dysfunction is characterized by decreased production of nitric oxide and increased expression of adhesion molecules. These molecules promote the internalization of monocytes, which transform into macrophages, releasing IL6, stimulating the release of CRP, which in turn promotes the reduction of nitric oxide, stimulates the release of IL-6 and the expression of endothelial adhesion molecules, perpetuating the inflammatory response 3. CRP is currently considered the main clinical marker of inflammation. Its involvement in the atherosclerotic process has been discussed for decades.

The relationship between CRP and cardiovascular disease has been investigated mainly in the coronary territory ^{5 , 6}. Observational studies have consistently shown that elevated CRP levels are associated with increased risk for coronary heart disease and its dosage aids in the prediction of disease ^{5 , 6}. However, these studies provide only limited and indirect information about the performance of the marker in predicting disease ⁷.

Currently, there is great interest about the real role of CRP in atherosclerosis: a causal factor or just a mediator of disease? The association between CRP and peripheral arterial disease (PAD) has been studied, however so much less extensively than in the coronary field ⁸.

Our group conducted a population-based study on the prevalence of diabetes mellitus and associated diseases in Japanese immigrants and their descendants in Brazil. Japanese populations of migrant origin have high rates of diabetes and other cardiovascular risk factors ⁹. A high prevalence of chronic diseases suggests that exposure to a different lifestyle exacerbates a genetic tendency to accumulate fat, increasing cardiovascular risk. These are genetically homogeneous populations, with unfavorable cardiometabolic profile, which contributes to the study of PAD and other complications of atherosclerosis ^{10 , 11}. Therefore, this population represents an opportunity to investigate the relationship of PAD with new risk factors, such as CRP.

METHODS

The study was conducted in the Japanese-Brazilian population living in Bauru, São Paulo, Brazil. Male and female individuals, aged e" 30 years were invited to participate. Details on the recruitment and selection of the sample population were previously described by the authors ^{10 , 11}.

The study was approved by the Ethics in Research Committee of the Federal University of São Paulo, under number 1544/10, and a free and informed consent was obtained from all participants. One thousand, three hundred and thirty participants were interviewed about clinical and nutritional status and scheduled for clinical and laboratory evaluation. Data on smoking and history of previous diseases were obtained. The clinical examination included anthropometric measures, blood pressure and ankle-brachial index (ABI). Blood sample was obtained after 12 hours of fasting for laboratory testing, including ultrasensitive C-reactive protein (CRP). After applying the exclusion criteria (incomplete data, CRP > 10mg/L and ABI > 1.40), 1,038 subjects completed the study.

Factors of conventional and non-conventional risk: since the population is of Asian origin, we chose to use the values of Body mass index (BMI) recommended by the Japan Society for the Study of Obesity (JASO) ¹². Values of waist-hip ratio used were those recommended by the World Health Organization (WHO) ¹³.

Hypertension was diagnosed in those who, during the data collection, mentioned they have the disease and were undergoing treatment, and in those who had, during the physical examination, pressure values higher than 140x90mmHg ¹⁴. For the diagnosis of dyslipidemia, we used the reference values recommended by the National Cholesterol Education Program (NCEP) ¹⁵. We considered diabetic patients who reported and were receiving drug treatment for the disease, and those who were diagnosed during the study according to the criteria of the American Diabetes Association (ADA) ¹⁶.

Concentrations of uric acid up to 6mg/dL for women and up to 7mg/dL for men were considered normal. The cutoff value for homocysteine was 15 mmol/L ¹⁷, while for CRP, the one corresponding to the population median value, which was 1.1 mg/L. Individuals with values of CRP higher than 10mg/L were excluded. Glucose and plasma lipoproteins were determined by enzymatic methods. Concentrations of CRP were determined by chemiluminescence.

The diagnosis of PAD was performed by using an 8MHz continuous wave doppler device (Imbracios(r)). The ABI was calculated as the quotient of auscultated pressure in the arteries of the ankle by the highest pressure obtained in the brachial arteries. As recommended by the TASC II (Transatlantic Society Consensus) ¹⁸, we considered abnormal a value d" 0.9 and> 1.40. We also stratified ABI into three categories: d" 0.70, from 0.71 to 0.90 and> 0.90 ¹⁹.

For the descriptive analysis, we used percentages, mean and standard deviations of the subjects' variables grouped according to the presence of PAD or to the ABI values (d" 0.70; 0.71 to 0.90; e" 0.90). We verified the existence of associations between variables through the use of chi-square and prevalence ratios (PR). For the comparison of variables mean values, according to the presence of PAD to the ABI values, we used the Student t test or analysis of variance, respectively. We applied the model of Poisson regression with robust variance in obtaining the PR of PAD according to the CRP median. We adopted a similar procedure to obtain the values of odds ratios according to the ABI values (d" 0.70; from 0.71 to 0.90; e" 0.90) and median CRP.

RESULTS

The mean age of the 1,038 Japanese-Brazilians evaluated was 56.8 years; 46% were male. The mean values of BMI, waist-hip ratio, blood pressure, fasting glucose, triglycerides, uric acid and homocysteine levels were significantly higher in men. Total cholesterol, LDL-cholesterol, HDL-cholesterol and CRP were significantly higher in women.

Table 1 shows the prevalence of conventional risk factors, CRP and homocysteine, in the population studied. Especially among men, we observed a high frequency of smoking (p < 0.01). Arterial hypertension did not differ between genders. As for disorders of glucose tolerance, the prevalence of DM was significantly higher among men (38.7% versus 31.7%, p = 0.008), who also more often presented hypertriglyceridemia, low HDL-cholesterol, hyperuricemia and hyperhomocysteinemia. Higher values of LDL-cholesterol and CRP were more frequent in women.

Table 1
Prevalence of the main cardiovascular risk factors in the Japanese-Brazilian population.

Variable			Gender				p value
		M a l e		Female	Total	(n=1038)
		(n=473)		(n=565)
		%		%	N	%
Age	>60 years	40.0		40.7	419	40.4	0.806
Smoking	No	46.2		88.8	717	69.3	<0 . 001
	Yes (past)	19.3		6.9	130	12.6
	Yes (current)	34.5		4.3	187	18.1
Abdominal obesity 1		25.7		72.9	532	51.4	<0 . 001
Body mass index	< 23 kg/m2	27.8		37.7	344	33.2	0.001
	23.0 a 24.9 kg/m2	22.6		23.0	237	22.9
	> 25 kg/m2	49.6		39.3	456	43.9
Arterial hypertension		47.2		43.9	471	45.4	0.295
Glucose tolerance	Normal	3.4		7.5	58	5.6	0.008
	GJA	35.9		36.7	377	36.4
	TGD	22.0		24.1	240	23.1
	DM	38.7		31.7	362	34.9
Hypercholesterolemia		60.0		64.1	646	62.2	0.182
Low HDL		16.5		9.0	129	12.4	<0 . 001
Increased LDL		43.1		52.7	502	48.4	0 . 0 0 2
Hypertriglyceridemia		72.3		58.2	671	64.6	<0 . 001
CRP	1.1-9.9	46.7		54.5	529	51.0	0 . 0 1 2
Homocysteine	>15 mg/dL	22.7		7.8	119	14.5	<0 . 001
High uric acid		54.3		75.4	683	65.7	<0 . 001

• ¹
  WHR waist-hip ratio

The prevalence of PAD was 21.1% (n = 219), with no difference between genders (19.2% vs. 22.7%), and was higher in subjects aged e" 60 years with hypertension and hyperhomocysteinemia. CRP was not associated with PAD (Table 2). In the adjusted analysis, we found a correlation between PAD and hypertension and current smoking, and no relationship of PAD with CRP (Table 3). In ABI stratified analysis, we observed a relation between PAD and hypertension and current smoking, and no relationship of PAD with CRP (Table 4).

Table 2
Number, percentage and prevalence ratios (PR) with respective 95% confidence intervals (95% CI) for Japanese-Brazilians according to the presence of PAD and demographic, anthropometric, clinical and biochemical variables.

Variable			DAOP		Chi - square	P R	9 5 % C i
		Y e s	N o	Total
		(n=219)	(n=819)	(n=1038)
		%	%	N
Gender	Female	22.7	77.3	565	1.80	1
	Male	19.2	80.8	473		0.85	0.67-1.08
Age	> 60 years	26.0	74.0	419		1 . 4 6	1 . 16 - 1 . 85
Smoking	Past	20.3	79.7	187	0.39	0.97	0.71-1.33
	Current	23.1	76.9	130		1.10	0.78-1.56
Abdominal obesity (WHR) 1		22.0	78.0	532	0.57	1.10	0.86-1.39
Body mass index	< 23 kg/m2	22.1	77.9	344	3.10	1
	23.0 a 24.9 kg/m2		24.1	75.9	237	1.09	0.81-1.47
	> 25 kg/m2	18.6	81.4	456		0.84	0.64-1.11
Hypertension		25.1	74.9	471	8 . 1	1 . 4 1	1 . 11 - 1 . 78
Glucose tolerance	Normal	13.8	86.2	58	4.40	1
	GJA	19.4	80.6	377		1.40	0.71-2.76
	TGD	24.6	75.4	240		1.78	0.90-3.52
	DM	21.8	78.1	362		1.58	0.81-3.10
Hypercholesterolemia		21.4	78.6	646	0.07	1.03	0.81-1.32
Low HDL		22.5	77.5	129	0.17	1.08	0.72-1.52
High LDL		21.3	78.7	502	0.03	1.02	0.81-1.29
Hypertriglyceridemia		21.3	78.7	671	0.05	1.03	0.80-1.32
CRP	1.1-9.9	22.5	77.5	529	1.26	1.15	0.90-1.45
Homocysteine	> 15 mg/dL	29.4	70.6	119	5 . 3 6	1 . 4 7	1 . 07 - 2 . 02

• ¹
  WHR waist-hip ratio.

Table 3
Values of prevalence ratios (PR) with their respective 95% confidence intervals (95% CI) for Japanese-Brazilians according to the presence of PAD and other variables (final and initial model).

Variable			Initial model		Final model
		P R	95% Ci	P R	95% Ci
CRP	<1.1	1		1
	1.1 – 9.9	1.00	0.73–1.38	1.03	0.76-1.39
Homocysteine	<15 mg/dL	1		1
	>15 mg/dL	1.25	0.88-1.77	1.26	0.89-1.78
Smoking	No	1		1
	Yes (past)	1.45	0.91-2.31	1.44	0.92-2.33
	Yes (current)	2.14	1.32-3.50	2 . 1 6	1 . 34 - 3 . 48
Age	? 60 years	1		1
	> 60 years	0.98	0.71-1.36	0.94	0.69-1.23
Gender	Female	1		1
	Male	0.66	0.42-1.02	0.66	0.44-1.01
Arterial hypertension	No	1		1
	Yes	1.61	1.12-2.31	1 . 5 6	1 . 12 - 2 . 22
Glucose tolerance	Normal	1
	GJA	0.67	0.38-1.21
	TGD	0.76	0.42-1.38
	DM	0.66	0.37-1.17

Table 4
Values of the odds ratios and their 95% confidence intervals (95% CI) for Japanese-Brazilians according to the ankle-brachial index and other variables (final and initial model).

Variable			Initial	model		Final model
			P R	95% Ci	P R	95% Ci
CRP		< 1.1 mg/L	1		1
		1.1 – 9.9 mg/L	0.97	0.55-1.72	1.04	0.61-1.78
Homocysteine		< 15 mg/dL	1		1
		> 15 mg/dL	1.51	0.73-3.15	1.52	0.73-3.15
Smoking		No	1		1
		Yes (past)	1.88	0.85-4.17	1.89	0.86-4.18
		Yes (current)	4.45	1.62-12.24	4 . 3 6	1 . 64 - 11 . 60
Age		< 60 years	1		1
		> 60 years	0.96	0.55-1.66	0.96	0.55-1.66
Gender		Female	1		1
		Male	0.45	0.21-0.94	0.50	0.25-0.99
Arterial hypertension		No	1		1
		Yes	2.20	1.24-3.91	2 . 2 5	1 . 28 - 3 . 95
Glucose tolerance		Normal	1
		GJA	0.57	0.16-2.09
		TGD	0.71	0.19-2.67
		DM	0.67	0.18-2.47

The analysis of the means, according to the stratification of the ABI, showed higher mean CRP in patients with ABI d" 0.70, but without statistical significance. Still, the mean age of participants with ABI d" 0.70 was higher than in other categories. The same occurred with the mean fasting and two-hour glucose, homocysteine, systolic blood pressure and number of cigarettes smoked per day (Table 5).

Table 5
Mean values and standard deviation (SD) of demographic, anthropometric, clinical and biochemical variables of Japanese-Brazilians according to the values of the ankle-brachial index.

Variable					Ankle-brachial Index					P
		<0,70		0,71 - 0,90		>0,90		F-Statistic
		Mean (SD)		Mean (SD)		Mean (SD)		(ANOVA)
Age (years)		65.1	(12.7)	59.3	(13.2)	56.0	(12.3)	10.14	< 0.001
Number of cigarettes per day *		22.5	(6.1)	17.9	(6.7)	17.3	(7.8)	1.99	0.141
WHR		0.91	(0.08)	0.87	(0.07)	0.88	(0.08)	3.06	0 . 0 4 7
BMI (kg/m2)		25.2	(4.8)	24.4	(3.7)	24.9	(3.8)	1.34	0.263
DBP (mmHg)		85.2	(11.7)	79.7	(13.9)	79.1	(13.2)	2.09	0.125
SBP (mmHg)		151.3	(23.0)	137.6	(27.5)	131.2	(23.4)	9.86	< 0.001
Fasting blood glucose (mg/dl) *		148.0	(49.1)	120.5	(28.3)	124.9	(35.2)	6.56	0 . 0 0 2
Two-hour glucose (mg/dl) *		239.2	(115.9)	164.1	(70.4)	162.2	(77.0)	7.45	0 . 0 0 1
Total cholesterol (mg/dl)		209.3	(31.2)	214.3	(40.8)	214.8	(43.1)	0.17	0.840
HDL (mg/dl) *		49.5	(10.8)	50.4	(10.2)	51.4	(11.7)	0.65	0.523
LDL cholesterol (mg/dl)		126.1	(26.5)	130.0	(38.8)	130.6	(38.1)	0.15	0.864
Triglycerides (mg/dl) *		282.0	(226.1)	227.3	(185.1)	231.4	(199.7)	1.09	0.336
CRP * (mg/L)		2.1	(2.3)	1.8	(1.6)	1.8	(1.8)	0.21	0.813
Homocysteine *		12.3	(5.8)	12.2	(6.5)	11.1	(6.0)	3.48	0 . 0 3 1

• ^*
  Values transformed into logarithm for the statistical test.

Furthermore, 70% of individuals with ABI d" 0.70 had diabetes mellitus and increased WHR values (Table 6).

Table 6
Number and percentage of Japanese-Brazilians according to the values of the ankle-brachial index and demographic, anthropometric, clinical and biochemical variables.

Variável				Ankle-brachial		Index					p
				<0,70 0,71 - 0,90 >0,90				Total		Chi - square
				(%)	(%)	N (%)		N (%)
Gender		Female		2.1	20.5	77.4		565	(100)	1.83	0.401
		Male		1.7	17.5	80.8		473	(100)
Age		< 60 years		1.0	16.8	82.2		619	(100)	1 3 . 9 4	<0 . 001
		> 60 years		3.3	22.7	74.0		419	(100)
Smoking1		Não		1.7	19.3	79.0		717	(100)	2.92	0.572
		Yes (past)		1.6	18.7	79.7		187	(100)
		Yes (current)		3.9	19.2	76.9		130	(100)
Abdominal obesity2		No		1.2	18.9	79.9		503	(100)	2.92	0.232
		Yes		2.6	19.4	78.0		532	(100)
Body mass index3		< 23 kg/m2		2.3	19.8	77.9		344	(100)	4.66	0.324
		23.0 a 24.9 kg/m2		1.3	22.8	75.9		237	(100)
		> 25 kg/m2		2.0	16.7	81.3		456	(100)
Hypertension		No		0.5	17.3	82.2		567	(100)	1 6 . 7 0	<0 . 001
		Yes		3.6	21.4	75.0		471	(100)
Glucose tolerance		Normal		-	13.8	86.2		58	(100)	1 5 . 5 8	0 . 0 1 6
		GJA		0.8	18.6	80.6		377	(100)
		TGD		1.3	23.3	75.4		240	(100)
		DM		3.9	18.0	78.1		362	(100)
Hypercholesterolemia		No		2.6	18.1	79.3		392	(100)	1.66	0.437
		Yes		1.6	19.8	78.6		646	(100)
Low HDL		No		1.9	19.0	79.1		909	(100)	0.23	0.891
		Yes		2.3	20.2	77.5		129	(100)
High LDL		No		2.2	18.7	79.1		536	(100)	0.72	0.698
		Yes		1.6	19.7	78.7		502	(100)
Hypertriglyceridemia		No		1.1	19.6	79.3		367	(100)	2.13	0.344
		Yes		2.4	18.9	78.7		671	(100)
CRP		< 1.1 mg/L		2.2	17.5	80.3		509	(100)	2.03	0.362
		1.1 – 9.9 mg/L		1.7	20.8	77.5		529	(100)
Homocysteine4		< 15 mg/dL		2.1	17.9	80.0		700	(100)	5.54	0.063
		>15 mg/dL		2.5	26.9	70.6		119	(100)

• ¹
  Four individuals without information
• ²
  WHR > 0.80 for women and > 0.90 for men
• ³
  Three individuals excluded without information
• ⁴
  One subject without information
• ⁵
  Homocysteine available for 819 individuals

DISCUSSION

We found a high prevalence of PAD (21.1%) in this population of Japanese-Brazilians. Given that the population presented unfavorable cardiometabolic profile, this high prevalence was expected. Another study, analyzing patients at high cardiovascular risk, found high rates of PAD ²⁰.

The risk factors independently associated with PAD were smoking and hypertension in both genders. CRP was not independently associated with PAD. However, with the stratification of the ABI, we found higher values of this variable in those with ABI d" 0.70, but without statistical significance. Nonetheless, this subgroup of patients with ABI d" 0.70 was composed of only 20 individuals, which makes the statistical analysis difficult. Still, individuals with more advanced disease (ABI d" 0.70) were those with the worst cardiometabolic profile, which can also interfere with CRP levels, a phenomenon called reverse causality, ie, the atherosclerotic plaque being a focus of inflammation, observed changes in CRP values could reflect only the inflammatory activity in the plate caused by other risk factors ²¹. Elevated CRP levels may be secondary to several factors, such as smoking, changes in the concentrations of total cholesterol, HDL-cholesterol, LDL-cholesterol, triglycerides and blood glucose, blood pressure and BMI in up to 78% of men and 67% of women ²². CRP therefore participates in the atherosclerotic process; however, its real role is still debatable, ie, if it is only a mediator of disease severity or is causally associated with it.

A cross-sectional study, "The Tsurugaya Project", similar to ours, also evaluating a population of Japanese origin, noted that patients with higher levels of CRP showed the lower ABI values (OR 2.10 [95% CI 1.13 3.88]), independent of other cardiovascular risk factors ²³.

Nevertheless, Wensley et al., in a meta-analysis on levels of CRP and risk of coronary and cerebral disease that included 194,418 individuals, concluded that the causal relationship between atherosclerosis and CRP levels are unlikely. Although there is a linear correlation between levels of CRP and atherosclerotic disease, the relationship weakens sharply after adjusting for other cardiovascular risk factors. According to these authors, CRP may be related to the severity of atherosclerotic disease ²⁴.

Genetic epidemiology has assisted in obtaining evidence about the involvement of CRP in atherosclerotic disease. The concentration of CRP is a hereditary trait, and there has already been identified the presence of polymorphisms in the CRP gene capable of influencing the circulating level of this protein. These findings open a new research opportunity, since the random allocation of alleles at conception allows a balanced distribution of confounding factors between genotypes. Still, the genotype is not influenced by the presence of disease, the genetic associations then being protected from reverse causality ²⁵.

With this objective, Zacho et al. studied the evolution of 51,286 individuals with CRP genotypes responsible for long-term maintenance of high plasma CRP levels and the occurrence of coronary or cerebral disease. They concluded that the polymorphism in the CRP gene was associated with high CRP plasma levels, but not with increased risk of coronary or cerebral ischemia ²⁶. Other studies evaluating the genetic epidemiology are consistent with the absence of a causal relationship between polymorphisms of the CRP gene with coronary disease ^{26 - 28}.

In summary, the published genetic studies ^{24 - 28} were not able to assign a causal role of CRP in atherosclerosis. The development of specific inhibitors for CRP should be of great help to arrive at this answer. Under development lies the 1,6 hexane-diphosphocholine, which has a very short half-life ²⁹. So far, the actual role of CRP in atherosclerosis is controversial. According to Pepys, CRP is present in atherosclerotic plaques, often collocated with the elements of the complement. The presence at the crime scene, however, is not necessarily evidence of guilt ³⁰.

Our findings suggest that CRP is a marker of severity or intensity of the disease. Since the CRP is released in response to an inflammatory process in the plate, the higher its value, the more intense the local inflammatory reaction. As the intensity of the inflammatory response corresponds to the intensity of atherosclerotic disease, the measurement of CRP may assist in the mapping of patients, identifying those that can evolve with worse prognosis.

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• Source of funding: none.

Publication Dates

• Publication in this collection
  May-Jun 2014

History

• Received
  17 Mar 2013
• Accepted
  10 May 2013