RESUMO
SUMMARY: The prevalence of radiographically ascertained vertebral fractures in a random sample of 413 in Mexican men is 9.7% (95% CI 6.85-12.55). Increase of vertebral fracture rises with age from 2.0% in the youngest group (50-59 years) to 21.4% in the oldest group (80 years and over). INTRODUCTION: This is the first population-based study of vertebral fractures in Mexican men using a standardized methodology reported in other studies. METHODS: The presence of radiographic vertebral fractures increases with age. This same pattern was found in Mexican women with steady age increments, but the higher prevalence of fractures in women starts at age 70, whereas in men, the higher prevalence starts a decade later (80 years and over). RESULTS: The standardized prevalence per 1,000 men 50 years and over in the Mexican population for the year 2005 is 65.8 (95% CI 29.9-105.5), and it is 68.6 (95% CI 32.2-108.7) in the US population for the year 2000.
Assuntos
Fraturas da Coluna Vertebral/epidemiologia , Distribuição por Idade , Idoso , Idoso de 80 Anos ou mais , Índice de Massa Corporal , Humanos , Masculino , México/epidemiologia , Pessoa de Meia-Idade , Prevalência , Radiografia , Fatores de Risco , Fraturas da Coluna Vertebral/diagnóstico por imagem , Fraturas da Coluna Vertebral/etiologiaRESUMO
UNLABELLED: In the first population-based study of vertebral fractures in Latin America, we found a 11.18 (95% CI 9.23-13.4) prevalence of radiographically ascertained vertebral fractures in a random sample of 1,922 women from cities within five different countries. These figures are similar to findings from studies in Beijing, China, some regions of Europe, and slightly lower than those found in the USA using the same standardized methodology. INTRODUCTION: We report the first study of radiographic vertebral fractures in Latin America. METHODS: An age-stratified random sample of 1,922 women aged 50 years and older from Argentina, Brazil, Colombia, Mexico, and Puerto Rico were included. In all cases a standardized questionnaire and lateral X-rays of the lumbar and thoracic spine were obtained after informed consent. RESULTS: A standardized prevalence of 11.18 (95% CI 9.23-13.4) was found. The prevalence was similar in all five countries, increasing from 6.9% (95% CI 4.6-9.1) in women aged 50-59 years to 27.8% (95% CI 23.1-32.4) in those 80 years and older (p for trend < 0.001). Among different risk factors, self-reported height loss OR = 1.63 (95% CI: 1.18-2.25), and previous history of fracture OR = 1.52 (95% CI: 1.14-2.03) were significantly (p < 0.003 and p < 0.04 respectably) associated with the presence of radiographic vertebral fractures in the multivariate analysis. In the bivariate analyses HRT was associated with a 35% lower risk OR = 0.65 (95% CI: 0.46-0.93) and physical activity with a 27% lower risk of having a vertebral fracture OR = 0.73 (95% CI: 0.55-0.98), but were not statistically significant in multivariate analyses CONCLUSION: We conclude that radiographically ascertained vertebral fractures are common in Latin America. Health authorities in the region should be aware and consider implementing measures to prevent vertebral fractures.
Assuntos
Vértebras Lombares/lesões , Osteoporose Pós-Menopausa/epidemiologia , Fraturas da Coluna Vertebral/epidemiologia , Vértebras Torácicas/lesões , Idoso , Idoso de 80 Anos ou mais , Argentina/epidemiologia , Estatura , Brasil/epidemiologia , Colômbia/epidemiologia , Terapia de Reposição de Estrogênios , Exercício Físico , Feminino , Humanos , Vértebras Lombares/diagnóstico por imagem , México/epidemiologia , Pessoa de Meia-Idade , Análise Multivariada , Osteoporose Pós-Menopausa/complicações , Osteoporose Pós-Menopausa/diagnóstico por imagem , Prevalência , Porto Rico/epidemiologia , Radiografia , Fraturas da Coluna Vertebral/complicações , Fraturas da Coluna Vertebral/diagnóstico por imagem , Vértebras Torácicas/diagnóstico por imagemRESUMO
The aim of this study was to generate standard curves for normal spinal and femoral neck bone mineral density (BMD) in Mexican women using dual-energy X-ray absorptiometry (DXA), to analyze geographic differences and to compare these with 'Hispanic' reference data to determine its applicability. This was a cross-sectional study of 4460 urban, clinically normal, Mexican women, aged 20-90 years, from 10 different cities in Mexico (5 in the north, 4 in the center and 1 in the southeast) with densitometry centers. Women with suspected medical conditions or who had used drugs affecting bone metabolism, were excluded. Lumbar spine BMD was significantly higher (1.089 +/- 0.18 g/cm2) in women from the northern part of Mexico, with intermediate values in the center (1.065 +/- 0.17 g/cm2) and lower values (1.013 +/- 0.19 g/cm2) in the southeast (p < 0.0001). Similarly, femoral neck BMD was significantly higher in women from the north (0.895 +/- 0.14 g/cm2), intermediate in the center (0.864 +/- 0.14 g/cm2) and lower (0.844 +/- 0.14 g/cm ) in the southeast part of Mexico (p < 0.0001). Northern Mexican women tend to be taller and heavier than women from the center and, even more, than those from the southeast of Mexico (p < 0.0001). However, these differences in BMD remained significant after adjustment for weight (p < 0.0001). A significant loss (p < 0.0001) in BMD was observed from 40 to 69 years of age at the lumbar spine and up to the eighth decade at the femoral neck. Higher and lower lumbar spine values, as compared with the 'Hispanic' population, were observed in Mexican mestizo women from the northern and southeastern regions, respectively. In conclusion, there are geographic differences in weight and height of Mexican women, and in BMD despite adjustment for weight.
Assuntos
Densidade Óssea/fisiologia , Absorciometria de Fóton/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos Transversais , Feminino , Humanos , Vértebras Lombares/diagnóstico por imagem , Vértebras Lombares/fisiologia , México/etnologia , Pessoa de Meia-Idade , Ossos Pélvicos/diagnóstico por imagem , Ossos Pélvicos/fisiologia , Padrões de Referência , Valores de Referência , Características de Residência , População UrbanaRESUMO
Defective fibrinolysis due to decreased tissue-type plasminogen activator (t-PA) activity is a well-established finding in patients with systemic lupus erythematosus (SLE). The possibility that this decrease in t-PA activity may be related to the presence of autoantibodies directed against t-PA, and the possible role of these autoantibodies in the pathophysiology of fibrinolysis in SLE, were investigated. Serum samples from 115 SLE patients and 63 normal volunteers were analyzed for the presence of such antibodies. The search for antibodies to t-PA was performed by means of several systems, allowing for the identification of epitopes presented in different conformational physical states of t-PA: free or associated to its inhibitor (PAI-1) in plasma, specifically bound to fibrin surface, or passively adsorbed to solid supports. Antibodies in variable amounts were detected by all systems used; however, t-PA activity was not inhibited by the IgG fraction of the positive sera in a fibrin-agar fibrinolysis system. Moreover, the demonstration of serum anti-t-PA antibodies was not associated with clinical or laboratory abnormalities related to vasoocclusive episodes. These results indicate that, as in the case of other autoantibodies, their detection in serum does not imply their direct participation in the pathophysiology of thrombosis in SLE.
Assuntos
Autoanticorpos/sangue , Epitopos/imunologia , Lúpus Eritematoso Sistêmico/imunologia , Ativador de Plasminogênio Tecidual/imunologia , Adolescente , Adulto , Idoso , Criança , Feminino , Humanos , Immunoblotting , Lúpus Eritematoso Sistêmico/sangue , Masculino , Pessoa de Meia-Idade , Nefelometria e Turbidimetria , Tromboflebite/imunologiaRESUMO
Antibodies directed to immunopurified coagulation protein C (PC) were investigated in serum samples from 108 patients with systemic lupus erythematosus (SLE) and found in 12 of them. However, their presence was not associated with antigenic or functional deficiencies of PC, which were documented in 6 and 17 patients, respectively.
Assuntos
Anticorpos/análise , Coagulação Sanguínea/fisiologia , Lúpus Eritematoso Sistêmico/imunologia , Deficiência de Proteína C , Proteína C/imunologia , Anticorpos/imunologia , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Lúpus Eritematoso Sistêmico/sangue , Proteína C/fisiologiaRESUMO
The association of thrombosis with antiphospholipid antibodies (aPL) in patients with systemic lupus erythematosus (SLE) could be due to their interference with natural phospholipid dependent anticoagulant mechanisms. We studied antigenic protein C (APC), functional protein C (FPC), free protein S (FPS), protein S bound to C4 binding protein (C4bp-S), antithrombin III (ATIII), as well as IgG and IgM anticardiolipin antibodies (aCL) in 38 patients with SLE with a history of thromboses and 70 patients with SLE without such history. We found a high frequency of deficiencies of natural anticoagulants in both groups of patients with SLE but, because of patient selection, we could not determine the actual prevalence of these defects. Patients having had a venous thrombosis in the previous year had low C4bp-S more frequently than patients with older or no thromboses. When we divided our patients with SLE into those who had a definite, probable, questionable or no antiphospholipid syndrome (aPS) we found the frequency of C4bp-S deficiency to be significantly higher in those with definite aPS than in those without aPS. Intermediate proportions were found in patients with probable and questionable aPS. The levels of C4bp-S decreased as the levels of aCL, particularly IgG, increased. Stepwise discriminant analysis of natural anticoagulants selected deficiencies of C4bp-S and FPC with increased ATIII as a set of variables with highest predictive power for classification of patients with and without aPS. Thus, deficiencies of natural anticoagulants may occur frequently in patients with SLE.(ABSTRACT TRUNCATED AT 250 WORDS)
Assuntos
Anticoagulantes/sangue , Proteínas de Transporte/metabolismo , Proteínas Inativadoras do Complemento , Glicoproteínas/deficiência , Lúpus Eritematoso Sistêmico/sangue , Adulto , Anticorpos/análise , Cardiolipinas/imunologia , Feminino , Glicoproteínas/metabolismo , Humanos , Lúpus Eritematoso Sistêmico/complicações , Masculino , Fosfolipídeos/imunologia , Proteína C/metabolismo , Proteína S , Síndrome , Tromboflebite/complicaçõesRESUMO
Five hundred consecutive patients with systemic lupus erythematosus (SLE) were entered into a prospective study of anticardiolipin antibodies (ACLA) in their 3 major immunoglobulin isotypes and followed thereafter with repeated testing for a mean period of nearly 8 months. Manifestations of SLE that were strongly associated with ACLA included venous thrombosis (particularly when recurrent), thrombocytopenia, hemolytic anemia, recurrent fetal loss, and leg ulcers. Other manifestations found to be associated with ACLA were arterial occlusions, transverse myelitis, and pulmonary hypertension. Conversely, we found no relationship between ACLA and migraine, convulsions, transient ischemic attacks, psychoses, or avascular necrosis of bone. No relationship was found between the presence of ACLA and that of anti-DNA antibodies studied in the same serum sample. Association with ACLA grew stronger and titers became higher in patients with several of the associated manifestations. Statistical analyses revealed the existence of a syndrome, the antiphospholipid syndrome, comprising 2 or more manifestations in conjunction with ACLA titers 5 standard deviations above the mean of normal control subjects, particularly if ACLA had been positive on at least 2 occasions. We propose that such criteria could be applied to the definition of the antiphospholipid syndrome. The presence and the titers of these antibodies related to disease activity and titer decreased by treatment, particularly when they were of the IgM isotype. Patients in whom a thrombotic episode occurred during the course of the study were observed to have a coincident decrease in ACLA titers, a finding that might indicate consumption of the antibody during the event. Treatment and the resulting inactivation of disease appear to have independent effects on ACLA titers. Physicians should therefore be cautious in prescribing high doses of corticosteroids or immunosuppressants to patients with SLE solely because they have high titers of ACLA.
Assuntos
Autoanticorpos/análise , Cardiolipinas/imunologia , Isotipos de Imunoglobulinas/análise , Lúpus Eritematoso Sistêmico/imunologia , Aborto Espontâneo/complicações , Adolescente , Adulto , Idoso , Criança , Feminino , Humanos , Úlcera da Perna/complicações , Lúpus Eritematoso Sistêmico/complicações , Masculino , Pessoa de Meia-Idade , Gravidez , Estudos Prospectivos , Síndrome , Tromboflebite/complicaçõesRESUMO
We studied 500 consecutive patients with systemic lupus erythematosus (SLE) for antibodies to phospholipids (APLA) by an ELISA method using cardiolipin as antigen and antiimmunoglobulins G, M and A to determine their isotype. Once entered into this prospective study the patients were followed for up to 16 months (mean 7.7 +/- 4.72 SD) with periodic determinations of APLA. Of the 500 patients with SLE, 88 had had thrombocytopenia, 25 had had hemolytic anemia, 25 had had both, and 362 had no history of these hemocytopenias. If we considered the odds ratio of these 362 patients for having high titer APLA as 1, patients with a history of thrombocytopenia, hemolytic anemia or both had significantly higher odds ratios of having APLA than did those without hemocytopenia. Patients with thrombocytopenia had significantly higher levels of IgG APLA, those with hemolytic anemia had significantly higher titers of IgM APLA and patients with both had significantly higher titers of both of these APLA isotypes, than did patients without hemocytopenias. A correlation between positive direct Coombs' tests and IgM APLA was also found. We conclude that APLA is associated with these hemocytopenias in SLE. This might be due to their interaction with negatively charged phospholipids in the cell walls of the respective cells.
Assuntos
Autoanticorpos/análise , Células Sanguíneas/patologia , Hemócitos/patologia , Lúpus Eritematoso Sistêmico/patologia , Fosfolipídeos/imunologia , Anemia Hemolítica/complicações , Cardiolipinas/imunologia , Contagem de Células , Humanos , Leucopenia/etiologia , Lúpus Eritematoso Sistêmico/complicações , Lúpus Eritematoso Sistêmico/imunologia , Linfócitos/patologia , Trombocitopenia/complicaçõesRESUMO
Ten of 12 patients with systemic lupus erythematosus (SLE) who had hemolytic anemia and thrombocytopenic purpura (Evans' syndrome) during their course had evidence of antiphospholipid antibodies either because they had a false positive VDRL test (8 patients), a prolonged partial thromboplastin time (5 patients), a lupus anticoagulant (3/4 patients), and/or anticardiolipin antibodies as determined by an ELISA method (7 patients). Antibodies to cardiolipin were found in very high levels (up to 38 standard deviations above the mean of normal controls) and were of both IgG and IgM isotypes. The 2 patients with SLE and Evans' syndrome who did not have evidence of antiphospholipid antibodies were studied at the onset of SLE which occurred with Evans' syndrome. Although cardiolipin is not a constituent of the cell wall of either platelets or erythrocytes, other phospholipids that cross react antigenically with cardiolipin are and can be exposed through cell damage. This could be a mechanism whereby hemolytic anemia and thrombocytopenia could occur in the same patient with SLE. Whether absorption of the antiphospholipid antibody during the acute episode of hemocytopenia could occur, and thus prevent its detection at such time, remains undetermined.