Associação de Fatores de Risco Cardiovascular e Polimorfismo de APOE com Mortalidade em Idosos Longevos: Uma Coorte de 21 Anos / Association of Cardiovascular Risk Factors and APOE Polymorphism with Mortality in the Oldest Old: A 21-Year Cohort Study

Resumo Fundamento: O conhecimento dos fatores ambientais e genéticos para um envelhecimento bem-sucedido em idosos longevos é controverso. Acrescenta-se a esta evidência, o fato de serem poucos os estudos delineados com essa população. Objetivo: Investigar a relação entre os genótipos mais frequentes da apolipoproteína E (APOE) e a mortalidade em idosos longevos que vivem em comunidade e sua sobrevida de acordo com os fatores de risco cardiovascular. Métodos: Uma amostra de 74 idosos com 80 anos ou mais da coorte do Projeto Veranópolis foi selecionada para genotipagem da APOE. Na linha de base, foram coletadas variáveis antropométricas, dosagens sanguíneas de glicose e lipídeos, pressão arterial e variáveis de estilo de vida (tabagismo, consumo de álcool e atividade física). A escala Bayer de Atividades da Vida Diária foi aplicada aos cuidadores dos idosos. O tempo de seguimento total do estudo foi 21 anos. Um p<0,05 bicaudal foi considerado estatisticamente significativo. Resultados: Não encontramos associação entre os genótipos da APOE e mortalidade. Entretanto, o risco de morte em idosos fumantes foi 2,30 vezes (hazard ratio [HR]; intervalo de confiança de 95% [IC 95%] 1,01 a 5,24); em diabéticos, 3,95 vezes (HR; IC 95% 1,27 a 12,30) do risco dos não diabéticos. Indivíduos que praticavam atividade física vigorosa tiveram uma redução no risco de óbito em 51% (HR = 0,49; IC 95% 0,27 a 0,88). Para o aumento de 1 mmHg na pressão arterial sistólica houve uma redução de 2% (HR = 0,98; IC 95% 0,97 a 0,99) no risco de morte. Conclusão: Nesta amostra de longevos, não houve associação entre os genótipos da APOE e mortalidade. Entretanto, os fatores de risco cardiovasculares clássicos podem ser importantes para a mortalidade geral em pessoas muito idosas.

Abstract Background: Knowledge of environmental and genetic factors for healthy aging in elderly people is controversial. In addition to this evidence, few studies have been designed for this population. Objectives: To investigate the relationship between the most frequent apolipoprotein E (APOE) genotypes and mortality in very elderly individuals living in a community and to evaluate survival according to cardiovascular risk factors. Methods: A sample of 74 elderly individuals aged ≥ 80 years, from the Veranópolis Project cohort, was selected for APOE genotyping. At baseline, anthropometric variables, glucose and lipid levels, blood pressure, and lifestyle variables (smoking, alcohol consumption, and physical activity) were collected. The Bayer Activities of Daily Living Scale was applied to their caregivers. Total study follow-up was 21 years. Two-sided p < 0.05 was considered statistically significant. Results: There was no association between APOE genotypes and mortality. However, the risk of death in elderly smokers was 2.30 times higher (hazard ratio [HR], 95% CI 1.01 to 5.24); in individuals with diabetes, it was 3.95 times higher (HR, 95% CI 1.27 to 12.30) than in individuals without diabetes. Subjects who practiced vigorous physical activity had a 51% reduction in risk of death (HR = 0.49, 95% CI 0.27 to 0.88). For an increase of 1 mmHg in systolic blood pressure, there was a 2% reduction (HR = 0.98, 95% CI 0.97 to 0.99) in risk of death. Conclusion: In this sample population, APOE genotypes were not associated with mortality. However, classic cardiovascular risk factors may be important for overall mortality in the very elderly.

Association of Cardiovascular Risk Factors and APOE Polymorphism with Mortality in the Oldest Old: A 21-Year Cohort Study. / Associação de Fatores de Risco Cardiovascular e Polimorfismo de APOE com Mortalidade em Idosos Longevos: Uma Coorte de 21 Anos.

BACKGROUND: Knowledge of environmental and genetic factors for healthy aging in elderly people is controversial. In addition to this evidence, few studies have been designed for this population. OBJECTIVES: To investigate the relationship between the most frequent apolipoprotein E (APOE) genotypes and mortality in very elderly individuals living in a community and to evaluate survival according to cardiovascular risk factors. METHODS: A sample of 74 elderly individuals aged ≥ 80 years, from the Veranópolis Project cohort, was selected for APOE genotyping. At baseline, anthropometric variables, glucose and lipid levels, blood pressure, and lifestyle variables (smoking, alcohol consumption, and physical activity) were collected. The Bayer Activities of Daily Living Scale was applied to their caregivers. Total study follow-up was 21 years. Two-sided p < 0.05 was considered statistically significant. RESULTS: There was no association between APOE genotypes and mortality. However, the risk of death in elderly smokers was 2.30 times higher (hazard ratio [HR], 95% CI 1.01 to 5.24); in individuals with diabetes, it was 3.95 times higher (HR, 95% CI 1.27 to 12.30) than in individuals without diabetes. Subjects who practiced vigorous physical activity had a 51% reduction in risk of death (HR = 0.49, 95% CI 0.27 to 0.88). For an increase of 1 mmHg in systolic blood pressure, there was a 2% reduction (HR = 0.98, 95% CI 0.97 to 0.99) in risk of death. CONCLUSION: In this sample population, APOE genotypes were not associated with mortality. However, classic cardiovascular risk factors may be important for overall mortality in the very elderly.

FUNDAMENTO: O conhecimento dos fatores ambientais e genéticos para um envelhecimento bem-sucedido em idosos longevos é controverso. Acrescenta-se a esta evidência, o fato de serem poucos os estudos delineados com essa população. OBJETIVO: Investigar a relação entre os genótipos mais frequentes da apolipoproteína E (APOE) e a mortalidade em idosos longevos que vivem em comunidade e sua sobrevida de acordo com os fatores de risco cardiovascular. MÉTODOS: Uma amostra de 74 idosos com 80 anos ou mais da coorte do Projeto Veranópolis foi selecionada para genotipagem da APOE. Na linha de base, foram coletadas variáveis antropométricas, dosagens sanguíneas de glicose e lipídeos, pressão arterial e variáveis de estilo de vida (tabagismo, consumo de álcool e atividade física). A escala Bayer de Atividades da Vida Diária foi aplicada aos cuidadores dos idosos. O tempo de seguimento total do estudo foi 21 anos. Um p<0,05 bicaudal foi considerado estatisticamente significativo. RESULTADOS: Não encontramos associação entre os genótipos da APOE e mortalidade. Entretanto, o risco de morte em idosos fumantes foi 2,30 vezes (hazard ratio [HR]; intervalo de confiança de 95% [IC 95%] 1,01 a 5,24); em diabéticos, 3,95 vezes (HR; IC 95% 1,27 a 12,30) do risco dos não diabéticos. Indivíduos que praticavam atividade física vigorosa tiveram uma redução no risco de óbito em 51% (HR = 0,49; IC 95% 0,27 a 0,88). Para o aumento de 1 mmHg na pressão arterial sistólica houve uma redução de 2% (HR = 0,98; IC 95% 0,97 a 0,99) no risco de morte. CONCLUSÃO: Nesta amostra de longevos, não houve associação entre os genótipos da APOE e mortalidade. Entretanto, os fatores de risco cardiovasculares clássicos podem ser importantes para a mortalidade geral em pessoas muito idosas.

Simultaneous use of amiodarone influences warfarin maintenance dose but is not associated with adverse events.

BACKGROUND: Drug interaction studies selecting patients in a real-life setting are scarce, and most studies to date are characterized by a small sample size. OBJECTIVE: To evaluate the effect of amiodarone on warfarin maintenance dose and adverse events in an anticoagulation cohort from a tertiary cardiovascular service. METHODS: This study recruited 866 patients, and oral anticoagulant therapy was monitored by the prothrombin time expressed as the international normalized ratio (INR). Genotyping of CYP2C9*2, CYP2C9*3, and VKORC1 3673 polymorphisms was performed. RESULTS: Of the 866 patients, 111 (12.8%) were taking amiodarone and warfarin simultaneously, and 514 (59.4%) reached the therapeutic target dose. The warfarin maintenance dose was significantly lower in patients simultaneously using amiodarone (23.8 ± 11.3 mg/wk) compared with other patients (29.5 ± 14.3 mg/wk; P < 0.001). Patients taking amiodarone had higher INR/current dose ratios (0.83 ± 0.04 per mg) compared with patients not using amiodarone (0.71 ± 0.02 per mg, P = 0.001). Adverse event frequency was not different between the groups (P = 0.40). No genotype effect was noted on the odds of bleeding associated with amiodarone use. CONCLUSIONS: Simultaneous use of amiodarone influences warfarin maintenance dose, but is not associated with adverse events.

Investigation of genetic disturbances in oxygen sensing and erythropoietin signaling pathways in cases of idiopathic erythrocytosis.

Background. Idiopathic erythrocytosis is the term reserved for cases with unexplained origins of abnormally increased hemoglobin after initial investigation. Extensive molecular investigation of genes associated with oxygen sensing and erythropoietin signaling pathways, in those cases, usually involves sequencing all of their exons and it may be time consuming. Aim. To perform a strategy for molecular investigation of patients with idiopathic erythrocytosis regarding oxygen sensing and erythropoietin signaling pathways. Methods. Samples of patients with idiopathic erythrocytosis were evaluated for the EPOR, VHL, PHD2, and HIF-2 α genes using bidirectional sequencing of their hotspots. Results. One case was associated with HIF-2 α mutation. Sequencing did not identify any pathogenic mutation in 4 of 5 cases studied in any of the studied genes. Three known nonpathogenic polymorphisms were found (VHL p.P25L, rs35460768; HIF-2 α p.N636N, rs35606117; HIF-2 α p.P579P, rs184760160). Conclusion. Extensive molecular investigation of cases considered as idiopathic erythrocytosis does not frequently change the treatment of the patient. However, we propose a complementary molecular investigation of those cases comprising genes associated with erythrocytosis phenotype to meet both academic and genetic counseling purposes.

CYP2C9 and VKORC1 polymorphisms influence warfarin dose variability in patients on long-term anticoagulation.

OBJECTIVES: The main aim of this study was to determine whether CYP2C9 and VKORC1 polymorphisms influence warfarin dose variability during initial dose-finding phase and during maintenance treatment after 360 days. METHODS: Two hundred and six consecutive patients who were beginning warfarin therapy were selected. They were assessed for general and clinical characteristics; prescribed warfarin dose; response to therapy on days 7-10, 30, 60, 180, and 360; adverse events; and CYP2C9 2, 3, 5, 6, 8, 11, and VKORC1 1639G >A assays. RESULTS: During the first 30 days of anticoagulation, the relative variability of warfarin dose was significantly associated with CYP2C9*2 and CYP2C9*3 polymorphisms (p = 0.02) and with VKORC1 1639G >A genotypes (p = 0.04). Warfarin variability was also statistically different according to predicted metabolic phenotype and to VKORC1 genotypes after 360 days of treatment, and in the phase between 180 and 360 days (long-term dose variability). Both CYP2C9 and VKORC1 polymorphisms were associated with the international normalized ratio (INR) made between 7 and 10 days/initial dose ratio, adjusted for covariates (p < 0.01 and p = 0.02, respectively). Patients carrying VKORC1 and CYP2C9 variants presented lower required dose (at the end of follow-up of 360 days) compared to patients carrying wild-type genotypes (p = 0.04 and p = 0.03, respectively). CONCLUSIONS: Genetic information on CYP2C9 and VKORC1 is important both for the initial dose-finding phase and during maintenance treatment with warfarin.

CYP2C9 and VKORC1 polymorphisms are differently distributed in the Brazilian population according to self-declared ethnicity or genetic ancestry.

BACKGROUND: Warfarin-dosing pharmacogenetic algorithms have presented different performances across ethnicities, and the impact in admixed populations is not fully known. AIMS: To evaluate the CYP2C9 and VKORC1 polymorphisms and warfarin-predicted metabolic phenotypes according to both self-declared ethnicity and genetic ancestry in a Brazilian general population plus Amerindian groups. METHODS: Two hundred twenty-two Amerindians (Tupinikin and Guarani) were enrolled and 1038 individuals from the Brazilian general population who were self-declared as White, Intermediate (Brown, Pardo in Portuguese), or Black. Samples of 274 Brazilian subjects from Sao Paulo were analyzed for genetic ancestry using an Affymetrix 6.0(®) genotyping platform. The CYP2C9*2 (rs1799853), CYP2C9*3 (rs1057910), and VKORC1 g.-1639G>A (rs9923231) polymorphisms were genotyped in all studied individuals. RESULTS: The allelic frequency for the VKORC1 polymorphism was differently distributed according to self-declared ethnicity: White (50.5%), Intermediate (46.0%), Black (39.3%), Tupinikin (40.1%), and Guarani (37.3%) (p<0.001), respectively. The frequency of intermediate plus poor metabolizers (IM+PM) was higher in White (28.3%) than in Intermediate (22.7%), Black (20.5%), Tupinikin (12.9%), and Guarani (5.3%), (p<0.001). For the samples with determined ancestry, subjects carrying the GG genotype for the VKORC1 had higher African ancestry and lower European ancestry (0.14±0.02 and 0.62±0.02) than in subjects carrying AA (0.05±0.01 and 0.73±0.03) (p=0.009 and 0.03, respectively). Subjects classified as IM+PM had lower African ancestry (0.08±0.01) than extensive metabolizers (0.12±0.01) (p=0.02). CONCLUSIONS: The CYP2C9 and VKORC1 polymorphisms are differently distributed according to self-declared ethnicity or genetic ancestry in the Brazilian general population plus Amerindians. This information is an initial step toward clinical pharmacogenetic implementation, and it could be very useful in strategic planning aiming at an individual therapeutic approach and an adverse drug effect profile prediction in an admixed population.

Genotyping of the hemochromatosis HFE p.H63D and p.C282Y mutations by high-resolution melting with the Rotor-Gene 6000® instrument.

BACKGROUND: The genotyping of HFE p.C282Y and p.H63D mutations is one of the most requested molecular analyses in the laboratorial routine. In this scenario, the main aim was to develop a genotyping assay that has advantages compared to other methods. METHODS: Genotypes for the HFE p.C282Y (c.G845A; rs1800562) and p.H63D (c.C187G, rs1799945) mutations were assessed by polymerase chain reaction (PCR) followed by high resolution melting (HRM) analysis with the Rotor-Gene 6000(®) instrument. Validation studies were conducted in samples bi-directionally sequenced. RESULTS: The melting assay was developed in a unique procedure and to ensure the result in approximately 112 min (31 min for sample preparation and 81 min for the PCR-HRM step). Genotypes for the HFE p.C282Y mutation were easily distinguished in the region of 80-86°C. For the HFE p.H63D, genotypes were also easily distinguished in the region of 76-82°C, but using the addition of known wild-type genotype DNA in all unknown samples plus a reaction without addition. In validation, genotypes were 100% concordant between methods. CONCLUSIONS: Our genotyping assay with the Rotor-Gene 6000(®) instrument applies to the laboratorial routine with several advantages, especially in large-scale demand. The main advantages were the non-dependence on gel electrophoresis and on mutagenic reagents for visualization of fragments, reduction of the chances for contamination due to sample preparation, the lack of use of probe-based methods and cost-effectiveness.