Browsing by Author "Chora, Joana Rita"
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- Advancements in risk stratification and management strategies in primary cardiovascular preventionPublication . Barkas, Fotios; Sener, Yusuf Ziya; Golforoush, Pelin Arabacilar; Kheirkhah, Azin; Rodriguez-Sanchez, Elena; Novak, Jan; Apellaniz-Ruiz, Maria; Akyea, Ralph Kwame; Bianconi, Vanessa; Ceasovschih, Alexandr; Chee, Ying Jie; Cherska, Mariia; Chora, Joana Rita; D'Oria, Mario; Demikhova, Nadiia; Kocyigit Burunkaya, Duygu; Rimbert, Antoine; Macchi, Chiara; Rathod, Krishnaraj; Roth, Lynn; Sukhorukov, Vasily; Stoica, Svetlana; Scicali, Roberto; Storozhenko, Tatyana; Uzokov, Jamol; Lupo, Maria Giovanna; van der Vorst, Emiel P.C.; Porsch, FlorentinaAtherosclerotic cardiovascular disease (ASCVD) remains a leading cause of morbidity and mortality worldwide, highlighting the urgent need for advancements in risk ssessment and management strategies. Although significant progress has been made ecently, identifying and managing apparently healthy individuals at a higher risk of developing atherosclerosis and those with subclinical atherosclerosis still poses significant challenges. Traditional risk assessment tools have limitations in accurately predicting future events and fail to encompass the complexity of the atherosclerosis trajectory. In this review, we describe novel approaches in biomarkers, genetics, advanced imaging techniques, and artificial intelligence that have emerged to address this gap. Moreover, polygenic risk scores and imaging modalities such as coronary artery calcium scoring, and coronary computed tomography angiography offer promising avenues for enhancing primary cardiovascular risk stratification and personalised intervention strategies. On the other hand, interventions aiming against atherosclerosis development or promoting plaque regression have gained attention in primary ASCVD prevention. Therefore, the potential role of drugs like statins, ezetimibe, proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitors, omega-3 fatty acids, antihypertensive agents, as well as glucose-lowering and anti-inflammatory drugs are also discussed. Since findings regarding the efficacy of these interventions vary, further research is still required to elucidate their mechanisms of action, optimize treatment regimens, and determine their long-term effects on ASCVD outcomes. In conclusion, advancements in strategies addressing atherosclerosis prevention and plaque regression present promising avenues for enhancing primary ASCVD prevention through personalised approaches tailored to individual risk profiles. Nevertheless, ongoing research efforts are imperative to refine these strategies further and maximise their effectiveness in safeguarding cardiovascular health.
- Classificação de variantes de hipercolesterolemia familiar pelo painel de peritos do Clinical Genome ResourcePublication . Chora, Joana Rita; Bourbon, Mafalda; em nome do FH Variant Curation Expert Panelhipercolesterolemia familiar (FH) é a patologia monogénica mais comum e caracteriza-se por valores muito elevados de colesterol em circulação, levando à sua deposição nas artérias e causando aterosclerose prematura. Indivíduos com FH têm variantes patogénicas, principalmente no gene LDLR (>90%), mas também nos genes APOB e PCSK9, genes estes muito importantes no metabolismo lipídico. O diagnóstico genético é o diagnóstico definitivo, mas existem atualmente mais de 3500 variantes diferentes no LDLR listadas na ClinVar, e no início deste trabalho, 565 apresentavam classificações conflituosas de patogenicidade, não permitindo assim confirmar o diagnóstico clínico nos indivíduos portadores destas variantes. Neste trabalho apresentamos o progresso da classificação de variantes no LDLR pelo FH Variant Curation Expert Panel (VCEP) do Clinical Genome Resource (ClinGen), segundo a recomendação publicada pelo mesmo grupo para classificação de variantes no gene LDLR. No processo de classificação das variantes no gene LDLR, laboratórios associados enviam dados internos de casos índex com a variante em estudo, que são colocados no Variant Curation Interface e complementados com evidências publicadas em artigos científicos e outros dados obtidos de outras bases de dados como descrito na recomendação. Cada variante é avaliada por um biocurador sénior ou dois juniores e aprovada por três revisores antes de ser publicada oficialmente na ClinVar. Atualmente avaliámos 531 variantes no gene LDLR. O FH VCEP classificou 5% destas variantes como benignas/provavelmente benignas, 39% como patogénicas/provavelmente patogénicas, 48% como variantes de significado incerto, 1% como conflituosas e 7% estão ainda em avaliação. As classificações definitivas aumentaram de 34% para 44%, e as classificações conflituosas diminuíram de 56% para 1%. O trabalho do FH VCEP visa melhorar o diagnóstico genético da FH, para o qual a classificação correta das variantes no LDLR é de extrema importância. As recomendações do FH VCEP diminuem significativamente as classificações conflituosas, melhorando o diagnóstico da FH no mundo inteiro.
- e_LIPID–Characterization of hypercholesterolemia and association with cardiovascular disease in the Portuguese populationPublication . Chora, Joana Rita; Alves, Ana Catarina; Mariano, Cibelle; Antunes, Marília; Rato, Quitéria; Bourbon, MafaldaThe e_LIPID study aimed to characterise the lipid profile of the Portuguese population and study its association with cardiovascular disease (CV D) events. Demographic, clinical, and biochemical data derived from the e_COR Study, a cross-sectional epidemiological study with 1688 adults (18-79 years old) from five Portuguese continental regions. Population specific percentiles for lipid and lipoprotein biomarkers were esmated stratified by sex and age. All calculations were weighted by sex, age, and geographic region to be representative of the mainland Portuguese population. Odds ratio was calculated to study association of biochemical profile with CV D. Associations of total cholesterol (TC), LDL, ApoB and non-HDL were performed only on individuals under no lipid-lowering therapy. Individuals with LDL above the 9th5 percentile and fulfilling Simon-Broome criteria of Familial Hypercholesterolemia (FH) were sequenced for LDLR, APOB and PCSK9. National prevalence of individuals with TC≥190mg/dl were 52.4%, with LDL≥116mg/dl were 53.9%, with ApoB≥90mg/dl were 53.8%, with non- HDL≥146mg/dl were 38.9%, and with Lp(a)≥125nmol/L were 21.1%. The 90th percentile for lipid and lipoprotein biomarkers for the Portuguese population are TC of 244mg/dl, LDL of 169mg/dl, ApoB of 128mg/dl, non-HDL of 193mg/dl, and Lp(a) of 223nmol/L. The 10th percentile for HDL is 38mg/dl. Individuals with LDL≥116mg/dl presented 2.50 [1.13-6.07] higher odds of having had CV D events (p=0.018), with non-HDL≥146mg/dl had 2.06 [1.01-4.31] higher odds (p=0.041), and with high Lp(a)≥125nmol/L had 1.77 [1.13-2.72] higher odds (p=0.008) than their respective counterparts. From the 33 individuals sequenced 3 individuals were found to have heterozygous FH. Population age and sex specific values are important for dyslipidaemia assessment. Having LDL≥116mg/dl, non-HDL≥146mg/dl or Lp(a) ≥125nmol/L can double the odds of CV D. Our results highlight that hypercholesterolemia is a neglected cardiovascular risk factor with more than 50% of the population with TC≥190mg/dl, LDL≥116mg/dl, or ApoB≥90mg/dl. Since hypercholesterolemia is a modifiable risk factor in the majority of cases, strategies to increase adherence to changes in lifestyle habits need to be urgently discussed.
- Estudo Português de Hipercolesterolemia FamiliarPublication . Medeiros, Ana Margarida; Alves, Ana Catarina; Chora, Joana Rita; Bourbon, MafaldaA Hipercolesterolemia Familiar (FH) é uma doença genética associada a um elevado risco cardiovascular. Doentes com FH possuem valores muito elevados de colesterol no plasma, desde o nascimento. Até à data 3 genes foram associados à FH: LDLR (85-90%), APOB (5-8%) e PCSK9 (1-2%). Em 1999 foi estabelecido, no Instituto Nacional de Saúde Doutor Ricardo Jorge, o Estudo Português de Hipercolesterolemia Familiar (EPHF). Este estudo de investigação tem como objetivo principal identificar a causa genética da dislipidemia em doentes com critérios clínicos de FH. O EPHF identificou molecularmente 718 doentes heterozigotos com uma variante patogénica ou provavelmente patogénica (segundo as diretrizes da ACMG) num dos 3 genes associados à FH. Adicionalmente, 90 indivíduos possuem uma das 35 variantes de significado incerto cuja patogenicidade necessita de ser avaliada através de estudos funcionais. Foram também identificados 10 homozigotos (3 homozigotos verdadeiros e 7 heterozigotos compostos), com variantes patogénicas nos genes LDLR e PCSK9. O EPHF conseguiu identificar 3,8% dos portugueses que se calcula terem FH, colocando Portugal entre os dez países com mais doentes identificados. O risco cardiovascular dos doentes com FH é determinado pelos valores elevados de colesterol que os doentes apresentam desde o nascimento, mas também pela patogenicidade da variante identificada. A identificação precoce dos doentes com FH, através do diagnóstico genético, permite ao clínico implementar medidas terapêuticas adequadas e mais agressivas, de modo a diminuir o risco cardiovascular inerente a estes doentes.
- Estudo Português de Hipercolesterolemia Familiar (1999-2021): relação fenótipo-genótipoPublication . Medeiros, Ana Margarida; Alves, Ana Catarina; Chora, Joana Rita; Miranda, Beatriz; Bourbon, Mafalda; em nome dos investigadores do Estudo Português de Hipercolesterolemia FamiliarA Hipercolesterolemia Familiar (FH) é uma condição genética comum do metabolismo dos lípidos, que se encontra subdiagnosticada. Existem três genes primários associados à FH (LDLR, APOB e PCSK9) e 5 genes fenocópias (LDLRAP1, LIPA, ABCG5, ABCG8 e APOE), que conferem um fenótipo semelhante à FH. Neste trabalho pretende-se apresentar a relação fenótipo-genótipo dos indivíduos com critérios clínicos de FH referenciados ao Estudo Português de Hipercolesterolemia Familiar. Até ao fim de 2021 foram estudados molecularmente 1005 indivíduos com critérios clínicos de FH. Destes, foram confirmados geneticamente com FH (FH positivos), 417 casos-índex (408 heterozigotos e 9 homozigotos). Com os estudos familiares identificaram- se adicionalmente 581 heterozigotos e 2 homozigotos. De entre os FH positivos, os casos-índex com variantes de alelo nulo apresentam um fenótipo mais severo do que os casos-índex com variantes de alelo defeituoso. Cerca de 1% dos casos-índex foram diagnosticados com outras causas monogénicas. Dos FH negativos, 34% apresenta hiper-Lp(a), 18% tem uma hipercolesterolemia de causa poligénica e 1% possui uma variante patogénica em heterozigotia nos genes fenocópias da FH. As diferentes causas genéticas contribuem para uma variedade de fenótipos que requerem diferentes formas de gestão da doença, terapias específicas e têm implicações na estratificação do risco cardiovascular e no rastreio dos familiares, sendo por esta razão essencial que seja identificada a etiologia da hipercolesterolemia o mais precocemente possível para melhorar o prognóstico dos indivíduos com FH.
- Familial hypercholesterolemia [CHAPTER 17]Publication . Chora, Joana Rita; Medeiros, Ana Margarida; Alves, Ana Catarina; Bourbon, MafaldaFamilial hypercholesterolemia (FH) is a common autosomal dominant disorder of lipid metabolism, with a heterozygous frequency of 1/250e1/500 in most of the European countries. Clinically FH is characterized by elevated concentrations of plasma cholesterol that accumulates in arteries and tendons from birth leading to premature coronary heart disease (pCHD). (...)
- Farmacogenética de fármacos antidislipidémicosPublication . Chora, Joana Rita; Bourbon, MafaldaDoentes com dislipidemia grave necessitam de tomar medicação antidislipidémica para diminuir as concentrações elevadas de colesterol de forma a reduzirem o seu elevado risco cardiovascular. Distintos tipos e/ou doses de estatinas levam a diferentes níveis de redução dos níveis de LDL-C, mas existe uma grande variação interpessoal na resposta, que se pensa estar associada a variantes nos genes envolvidos na farmacodinâmica e farmacocinética desta classe de fármacos. Este trabalho tem como objetivo determinar a prevalência de genótipos associados a uma menor eficácia ou a um maior risco de efeitos secundários adversos no tratamento com estatinas na população portuguesa. Foram genotipados vários SNPs envolvidos no metabolismo, absorção, transporte e/ou excreção dos vários tipos de estatinas numa amostra de adultos da população portuguesa proveniente das diferentes regiões do país. A variante SLCO1B1*5, associada com um maior risco de desenvolver miopatia com o tratamento com sinvastatina, tem uma frequência 2 vezes superior na nossa amostra do que o descrito nas bases de dados populacionais. Este fato, aliado ao grande aumento de consumo nacional de estatinas, principalmente de sinvastatina, é um fator importante que deve ser considerado na tomada de decisão da prescrição de antidislipidémicos.
- Functional studies of APOB variants the experience of the Portuguese Familial Hypercholesterolemia StudyPublication . Ferreira, Maria Simões; Chora, Joana Rita; Medeiros, Ana Margarida; Bourbon, Mafalda; Alves, Ana CatarinaFamilial hypercholesterolemia (FH) is clinically characterized by increased levels of circulating LDL cholesterol leading to premature coronary heart disease. It can be caused by variants in LDLR, APOB, and PCSK9 genes. APOB variants are responsible for 5-10% of the FH cases, p.(Arg3527Gln) being the most common. Only recently the whole gene has been sequenced due to Next Generation Sequencing, increasing the variant spectrum of APOB and with it the number of variants that need to be functionally assessed. We aimed to characterize novel APOB variants identified in patients included in the Portuguese FH Study to confirm if they are the genetic cause of hypercholesterolemia. To better analyze these variants, we also create a database with all APOB rare variants found up to date in the Portuguese FH Study. The functional study of 5 variants is ongoing. To access if these variants affect apoB:LDL receptor binding, LDL from index cases and relatives with the variants was separated using sequential ultracentrifugation, and proliferation assays were performed with U937 cells. These cells do not synthesize cholesterol and they depend on apoB:LDL receptor binding to grow.
- Generation and validation of a classification model to diagnose familial hypercholesterolaemia in adultsPublication . Albuquerque, João; Medeiros, Ana Margarida; Alves, Ana Catarina; Jannes, Cinthia Elim; Mancina, Rosellina M.; Pavanello, Chiara; Chora, Joana Rita; Mombelli, Giuliana; Calabresi, Laura; Pereira, Alexandre da Costa; Krieger, José Eduardo; Romeo, Stefano; Bourbon, Mafalda; Antunes, MaríliaBackground and aims: The early diagnosis of familial hypercholesterolaemia is associated with a significant reduction in cardiovascular disease (CVD) risk. While the recent use of statistical and machine learning algorithms has shown promising results in comparison with traditional clinical criteria, when applied to screening of potential FH cases in large cohorts, most studies in this field are developed using a single cohort of patients, which may hamper the application of such algorithms to other populations. In the current study, a logistic regression (LR) based algorithm was developed combining observations from three different national FH cohorts, from Portugal, Brazil and Sweden. Independent samples from these cohorts were then used to test the model, as well as an external dataset from Italy. Methods: The area under the receiver operating characteristics (AUROC) and precision-recall (AUPRC) curves was used to assess the discriminatory ability among the different samples. Comparisons between the LR model and Dutch Lipid Clinic Network (DLCN) clinical criteria were performed by means of McNemar tests, and by the calculation of several operating characteristics. Results: AUROC and AUPRC values were generally higher for all testing sets when compared to the training set. Compared with DLCN criteria, a significantly higher number of correctly classified observations were identified for the Brazilian (p < 0.01), Swedish (p < 0.01), and Italian testing sets (p < 0.01). Higher accuracy (Acc), G mean and F1 score values were also observed for all testing sets. Conclusions: Compared to DLCN criteria, the LR model revealed improved ability to correctly classify observations, and was able to retain a similar number of FH cases, with less false positive retention. Generalization of the LR model was very good across all testing samples, suggesting it can be an effective screening tool if applied to different populations.
- Genetic background of individuals with clinical diagnosis of FH from the Portuguese FH Study cohortPublication . Medeiros, Ana Margarida; Alves, Ana Catarina; Chora, Joana Rita; Miranda, Beatriz Raposo; Bourbon, MafaldaAim: Familial Hypercholesterolemia (FH) is a common genetic disorder of lipid metabolism associated to increased CAD risk. Three genes are associated with FH (LDLR, APOB, PCSK9). Variants in FH phenocopies genes (LDLRAP1, APOE, LIPA, ABCG5, ABCG8), LDL-C polygenic risk score (PRS) and hyper-Lp(a) can mimic the FH phenotype. In the present work we intend to unravel the genetic background in individuals with clinical diagnosis of FH. Methods: A biochemical and genetic study was performed to 1005 patients with clinical diagnosis of FH referred to the Portuguese FH Study until December 2021. Since 2017, genetic diagnosis is performed by an NGS panel with 8 genes and 6-SNPs to determine PRS. Results: FH was genetically confirmed in 41% of the cases. In the FH-negative cohort (N=590), 30% (N=177) present Lp(a)>50mg/dl, 16% (N=95) have high PRS, 1% (N=7) have other monogenic cause and 1% (N=7) have one pathogenic variant in ABCG5/ABCG8. Additionally, 11% (N=61) carry heterozygous VUS in either LDLR, APOB or PCSK9 and 5% (N=29) carry heterozygous variants of unknown significance (VUS) in FH phenocopies genes. No identifiable cause of dyslipidemia was found in the remaining 36% patients. Conclusions: Overall, FH was confirmed genetically in 41% of the cohort. In 50% of the FH negatives the FH phenotype can be caused by Hyper-Lp(a) or high PRS. A small part of patients has pathogenic variants in ABCG5/8 in heterozygosity and this can be the cause of hypercholesterolemia and should be further investigated. This extended NGS panel is important to identify FH/FH-phenocopies and therefore personalize each patient’s treatment