| Resumen: | Base teórica - A doença obstrutiva severa de artérias carótidas (DOSAC) está relacionada à aterosclerose (ATC). Mecanismos de inflamação e auto-imunidade podem influenciar o deflagramento da ATC. Neste contexto, incluem-se anticorpos antifosfolípides (AAF), marcadores da síndrome antifosfolipídica (SAF) e anticorpos contra proteínas de choque térmico (anti-Hsp). A beta2-glicoproteína I (beta2-gpI) e as Hsp de 60 e 65 kilodaltons (kDa) são moléculas encontradas em ateromas. O relato é o primeiro a incluir a pesquisa de IgA anticardiolipina (aCL), IgG/IgM/IgA antibeta2-gpI e anti-HSP em casuísticas de DOSAC. Objetivo - Avaliar a associação, se alguma, entre ocorrência de AAF/anti-Hsp e DOSAC. Pacientes e Métodos - Neste estudo de caso-controle, os casos consistiram de uma população de pacientes com DOSAC (sintomática ou assintomática). A presença de DOSAC foi definida pela anamnese, exame físico, angiografia por ressonância nuclear magnética (ARM) e endarterectomia de carótida. Os controles foram selecionados de enfermarias de ortopedia. Ambos os grupos foram avaliados quanto aos fatores de risco: idade, sexo, raça, hipertensão arterial sistêmica (HAS), tabagismo, diabete mellitus (DM) e hipercolesterolemia. Anticorpos IgG/IgM/IgA aCL, IgG/IgM/IgA antibeta2-gpI, IgG anti-Hsp 60 kDa humana recombinante e IgG anti-Hsp 65 kDa de Mycobacterium bovis foram detectados através de ensaio enzimático. Para estimar o grau de associação dos anticorpos com DOSAC, razão de chances (odds ratios, OR) foram calculadas com seus respectivos IC 95%.Regressão logística foi utilizada para ajuste de fatores de confusão. Resultados - Entre os 57 casos e 93 controles estudados, a média de idade foi de 66 + 8,7 anos nos casos e de 47,5 + 18,8 anos nos controles (P<0,001). A raça negra predominou no grupo controle. O sexo masculino foi mais freqüente nos casos (61,4%), situação que se inverteu nos controles (49,5%). As presenças de HAS (OR=21,0; IC95% 8,0 a 57,1; P<0,001) e de hipercolesterolemia (OR=25,5; IC95% 9,5 a 70,9; P<0,001) determinaram, entre os fatores de risco conhecidos, as mais fortes associações com DOSAC. Anticorpos IgA antibeta2-gpI foram detectados em 33,3% dos casos e em 9,7% dos controles (OR ajustado 4,7; IC95% 1,0 a 23,7; P=0,06). A freqüência dos outros anticorpos testados não diferiu significantemente em casos e controles. Conclusão - Não houve associação entre ocorrência de aCL, IgG/IgM antibeta2- gpI, anti-Hsp e desfecho DOSAC. A presença de anticorpos IgA antibeta2-gpI se configurou como fator de risco independente para DOSAC (OR ajustado 4,7), embora com significância limítrofe (P=0,06). A associação de IgA antibeta2-gpI com DOSAC pode representar um dos elos na relação auto-imunidade e aterosclerose carotídea.
Theoretical basis – Severe obstructive carotid artery disease is related to atherosclerosis (ATC). Mechanisms of inflammation and self-immunity may have influence on the occurrence of ATC. This includes antiphospholipid antibodies (AAP), antiphospholipid syndrome markers (APS) and antibodies against heat shock proteins (anti-Hsp). A beta 2-glycoprotein I (beta2-gpI) and the 60 and 65 kilodaltons (kDa) Hsp are molecules present in atherosclerotic plaques. This is the first report including research on IgA anticardiolipin (aCL), IgG/IgM/IgA anti-beta2- glycoprotein I and anti-HSP in severe obstructive carotid artery disease cases. Objective – To determine the association, if any, between the presence of AAP/anti-Hsp and the occurrence of severe obstructive carotid artery disease. Patients and Methods – In our control case study the cases consisted of patients with either symptomatic or asymptomatic severe obstructive carotid artery disease. The presence of the disease was determined by anamnesis, physical examination, MR angiography (MRA) and carotid endarterectomy. The control group consisted of patients admitted to orthopedic wards. Both groups were assessed for risk factors: age, sex, race, hypertension, smoking, diabetes mellitus (DM) and hypercholesterolemy. IgG/IgM/IgA aCL, IgG/IgM/IgA anti-beta2-gpI, IgG anti-Hsp 60 kDa recombinant human and IgG anti-Hsp 65 kDa of Mycobacterium bovis antibodies were detected by enzymatic test. In order to assess the degree of association between antibodies with severe obstructive carotid artery disease, (odds ratios, OR) were calculated with their respective confidence intervals (IC 95%).Logistic regression was used to adjust the confusion factors. Results – 57 case patients and 93 control patients were studied and the average age was 66 + 8. 7 years for case patients and 47. 5 + 18. 8 years for control patients (P<0. 001). There was a predominance of black race individuals in the control group. Most case patients were male individuals (61. 4%), but there were less male individuals (49. 5%) among control patients. The presence of hypertension (OR=21. 0; IC 95% 8. 0 to 57. 1; P<0. 001) and hypercholesterolemy (OR=25. 5; IC 95% 9. 5 to 70. 9; P<0,001) determined the strongest associations between the risk factors already known and severe obstructive carotid artery disease. IgA antibeta2-gpI antibodies were detected in 33. 3% of the case patients and in 9. 7% of the control patients (OR adjusted 4. 7; IC 95% 1. 0 to 23. 7; P=0. 06). The frequency of other non-tested antibodies was not significantly different in cases and controls. Conclusion – No association was found between the presence of aCL, IgG/IgM antibeta2-gpI, anti-Hsp and the occurrence of severe obstructive carotid artery disease. The presence of IgA antibeta2-gpI antibodies was found to be an independent risk factor for severe obstructive carotid artery disease (OR adjusted 4. 7), although with borderline significance (P=0,06). The association of IgA antibeta2-gpI with severe obstructive carotid artery disease may be one of the links between auto-immunity and carotid. |
