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1.
HIV Med ; 21 Suppl 2: 3-16, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32881311

RESUMO

Undoubtedly, comorbidities complicate long-term HIV management and have significant cost implications for healthcare systems. A better understanding of these comorbidities and underlying causes would allow for a more considered and proactive approach to the long-term management of HIV. This review examines cross-sectional analyses of six European cohort studies (Athens Multicenter AIDS Cohort Study, Aquitaine Cohort, EuroSIDA Cohort study, French claims EGB, German InGef Cohort and the Italian Cohort of Individuals, Naïve for Antiretrovirals), which included individuals with HIV followed over a certain period of time. Based on these cohorts, we examined how comorbidities have changed over time; how they compromise HIV management; and how much of a financial burden they impart. These data also provided a framework to explore the major issues of ageing and HIV and the practical implications of managing such issues in real-life practice.


Assuntos
Antirretrovirais/uso terapêutico , Comorbidade , Infecções por HIV/tratamento farmacológico , Gastos em Saúde , Envelhecimento , Estudos Transversais , Gerenciamento Clínico , Europa (Continente) , Feminino , Humanos , Masculino
2.
HIV Med ; 19(3): 184-194, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29230953

RESUMO

OBJECTIVES: To investigate factors that predict speed of recovery and long-term CD4 cell count in HIV-1 seroconverters initiating combination antiretroviral therapy (cART), and to quantify the influence of very early treatment initiation. We make use of all pre-treatment CD4 counts, because analyses using only a single observation at initiation may be subject to biases. METHODS: We used data from the CASCADE (Concerted Action on SeroConversion to AIDS and Death in Europe) multinational cohort collaboration of HIV-1 seroconverters. We analysed pre- and post-treatment data of patients with seroconversion dates estimated January 2003-March 2014 (n = 7600 for primary analysis) using a statistical model in which the characteristics of recovery in CD4 counts are determined by multiple predictive factors. Secondary analyses were performed incorporating uncertainty in the exact timing of seroconversion to allow more precise estimation of the benefit of very early treatment initiation. RESULTS: 'True' CD4 count at cART initiation was the strongest predictor of CD4 count beyond 3 years on cART. Allowing for lack of complete certainty in the date of seroconversion, CD4 recovery was more rapid for patients in whom treatment was initiated within 4 months. For a given CD4 count, higher viral load (VL) at initiation was strongly associated with higher post-treatment CD4 recovery. For other patient and drug characteristics, associations with recovery were statistically significant but small in magnitude. CONCLUSIONS: CD4 count at cART initiation is the most important factor in predicting post-treatment recovery, but VL provides substantial additional information. If cART is initiated in the first 4 months following seroconversion, recovery of CD4 counts appears to be more rapid.


Assuntos
Fármacos Anti-HIV/uso terapêutico , Infecções por HIV/imunologia , HIV-1/imunologia , Contagem de Linfócito CD4 , Feminino , Infecções por HIV/tratamento farmacológico , Humanos , Masculino , Modelos Estatísticos , Soroconversão , Resultado do Tratamento , Carga Viral
3.
Acta Psychiatr Scand ; 137(1): 18-29, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29178463

RESUMO

OBJECTIVE: It still remains unclear whether psychotic features increase the risk of suicidal attempts in major depressive disorder. Thus, we attempted, through a systematic review coupled with a meta-analysis, to elucidate further whether unipolar psychotic depression (PMD) compared to non-PMD presents higher levels of suicidal attempts. METHOD: A systematic search was conducted in PubMed, EMBASE, PsycINFO as well as in various databases of the so-called gray literature for all studies providing data on suicidal attempts in PMD compared to non-PMD, and the results were then subjected to meta-analysis. RESULTS: Twenty studies met our inclusion criteria, including in total 1,275 PMD patients and 5,761 non-PMD patients. An elevated risk for suicide attempt for PMD compared to non-PMD patients was found: The total (lifetime) fixed-effects pooled OR was 2.11 (95% CI: 1.81-2.47), and the fixed-effects pooled OR of the five studies of the acute phase of the disorder was 1.93 (95% CI: 1.33-2.80). This elevated risk of suicidal attempt for PMD patients remained stable across all age groups of adult patients. CONCLUSION: Despite data inconsistency and clinical heterogeneity, this systematic review and meta-analysis showed that patients with PMD are at a two-fold higher risk, both during lifetime and in acute phase, of committing a suicidal attempt than patients with non-PMD.


Assuntos
Transtornos Psicóticos Afetivos/epidemiologia , Delusões/epidemiologia , Transtorno Depressivo Maior/epidemiologia , Tentativa de Suicídio/estatística & dados numéricos , Transtornos Psicóticos Afetivos/psicologia , Estudos de Casos e Controles , Delusões/psicologia , Transtorno Depressivo Maior/psicologia , Humanos
4.
HIV Med ; 18(3): 171-180, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-27625109

RESUMO

OBJECTIVES: The aim of the study was to determine the time to, and risk factors for, triple-class virological failure (TCVF) across age groups for children and adolescents with perinatally acquired HIV infection and older adolescents and adults with heterosexually acquired HIV infection. METHODS: We analysed individual patient data from cohorts in the Collaboration of Observational HIV Epidemiological Research Europe (COHERE). A total of 5972 participants starting antiretroviral therapy (ART) from 1998, aged < 20 years at the start of ART for those with perinatal infection and 15-29 years for those with heterosexual infection, with ART containing at least two nucleoside reverse transcriptase inhibitors (NRTIs) and a nonnucleoside reverse transcriptase inhibitor (NNRTI) or a boosted protease inhibitor (bPI), were followed from ART initiation until the most recent viral load (VL) measurement. Virological failure of a drug was defined as VL > 500 HIV-1 RNA copies/mL despite ≥ 4 months of use. TCVF was defined as cumulative failure of two NRTIs, an NNRTI and a bPI. RESULTS: The median number of weeks between diagnosis and the start of ART was higher in participants with perinatal HIV infection compared with participants with heterosexually acquired HIV infection overall [17 (interquartile range (IQR) 4-111) vs. 8 (IQR 2-38) weeks, respectively], and highest in perinatally infected participants aged 10-14 years [49 (IQR 9-267) weeks]. The cumulative proportion with TCVF 5 years after starting ART was 9.6% [95% confidence interval (CI) 7.0-12.3%] in participants with perinatally acquired infection and 4.7% (95% CI 3.9-5.5%) in participants with heterosexually acquired infection, and highest in perinatally infected participants aged 10-14 years when starting ART (27.7%; 95% CI 13.2-42.1%). Across all participants, significant predictors of TCVF were those with perinatal HIV aged 10-14 years, African origin, pre-ART AIDS, NNRTI-based initial regimens, higher pre-ART viral load and lower pre-ART CD4. CONCLUSIONS: The results suggest a beneficial effect of starting ART before adolescence, and starting young people on boosted PIs, to maximize treatment response during this transitional stage of development.


Assuntos
Antirretrovirais/uso terapêutico , Farmacorresistência Viral , Infecções por HIV/tratamento farmacológico , Grupos Populacionais , Adolescente , Adulto , Criança , Pré-Escolar , Estudos de Coortes , Europa (Continente) , Feminino , Humanos , Lactente , Masculino , Fatores de Tempo , Falha de Tratamento , Adulto Jovem
5.
Hippokratia ; 20(3): 214-221, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-29097888

RESUMO

BACKGROUND AND AIMS: Although effective treatment in terms of inducing virological and biochemical response for chronic hepatitis B (CHB) is available, its effect on the clinical course of the disease has not yet been accurately estimated. Objective of this study was to evaluate the effect of antiviral therapy and its type [interferon +/- nucleos(t)ide analogs (NAs) vs. NAs] on the occurrence of a clinical event (liver decompensation, liver transplant, hepatocellular carcinoma and death from a liver-related cause) in CHB patients. METHODS: The study population was derived from the HEPNET-Greece, a nationwide cohort study aimed to evaluate the current epidemiological course of viral hepatitis. To account for time-dependent confounding, Cox marginal structural models were used to analyze data. RESULTS: Thirty out of 2,125 eligible patients experienced a clinical event during their follow-up. When comparing treated to untreated individuals, the hazard ratio (HR) for a clinical event was 0.39 (95% CI: 0.16-0.98; p =0.044) in the whole sample, whereas there were indications of a more intense effect in the subgroup of patients with cirrhosis at presentation (HR =0.16, 95% CI: 0.02-1.21; p =0.075). The effect of Interferon initiated treatment was not significantly different of that of NAs. There was some evidence, albeit not statistically significant, of a protective treatment effect on hepatocellular carcinoma development (HCC). CONCLUSIONS: Data from observational studies can provide useful inference, provided they are analyzed appropriately. The current study has shown that the available treatment options for CHB offer a significant clinical benefit to CHB infected individuals. Hippokratia 2016, 20(3): 214-221.

6.
HIV Med ; 16 Suppl 1: 24-9, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25711320

RESUMO

OBJECTIVES: Efforts are needed to improve informed consent of participants in research. The Strategic Timing of AntiRetroviral Therapy (START) study provides a unique opportunity to study the effect of length and complexity of informed consent documents on understanding and satisfaction among geographically diverse participants. METHODS: Interested START sites were randomized to use either the standard consent form or the concise consent form for all of the site's participants. RESULTS: A total of 4473 HIV-positive participants at 154 sites world-wide took part in the Informed Consent Substudy, with consent given in 11 primary languages. Most sites sent written information to potential participants in advance of clinic visits, usually including the consent form. At about half the sites, staff reported spending less than an hour per participant in the consent process. The vast majority of sites assessed participant understanding using informal nonspecific questions or clinical judgment. CONCLUSIONS: These data reflect the interest of START research staff in evaluating the consent process and improving informed consent. The START Informed Consent Substudy is by far the largest study of informed consent intervention ever conducted. Its results have the potential to impact how consent forms are written around the world.


Assuntos
Antirretrovirais/uso terapêutico , Terapia Antirretroviral de Alta Atividade/métodos , Infecções por HIV/tratamento farmacológico , Consentimento Livre e Esclarecido/normas , Adulto , Contagem de Linfócito CD4 , Estudos de Coortes , Feminino , Infecções por HIV/imunologia , Infecções por HIV/patologia , Humanos , Masculino , Fatores de Tempo , Resultado do Tratamento
7.
J Viral Hepat ; 22(2): 120-7, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25040685

RESUMO

Hepatocellular carcinoma (HCC) may still develop in chronic hepatitis B (CHB) patients treated with lamivudine. Whether HCC rates are comparable in patients treated with the current first-line antivirals remains uncertain. We estimated the incidence and evaluated predictors of HCC in a large nationwide prospective cohort (HepNet.Greece) of HBeAg-negative CHB patients treated with entecavir. HBeAg-negative CHB patients from the same cohort who were initially treated with lamivudine were used as controls. We included 321 patients treated with entecavir for a median of 40 months and 818 patients treated initially with lamivudine for a median of 60 months. In the entecavir group, HCC developed in 4 of 321 (1.2%) patients at a median of 1.5 (range: 1.0-4.5) years, while the cumulative HCC incidence was significantly higher in cirrhotics than noncirrhotics (1, 3, 5 years: 0%, 3%, 9% vs 1%, 1%, 1%; P = 0.024) and in older patients (P = 0.026). Entecavir compared with lamivudine group patients had lower HCC incidence (1, 3, 5 years: 0.3%, 1.2%, 2.8% vs 0.7%, 3.8%, 5.6%; P = 0.024). However, in multivariable Cox regression analysis, the HCC risk was independently associated with older age (P < 0.001), male gender (P = 0.011) and cirrhosis (P = 0.025), but not with the initial agent. In conclusion, our large nationwide study indicates that the HCC risk remains increased in entecavir-treated HBeAg-negative CHB patients with cirrhosis, particularly of older age, at least for the first 5 years. The HCC risk does not seem to be significantly reduced with entecavir compared with antiviral therapy starting with lamivudine.


Assuntos
Antivirais/uso terapêutico , Carcinoma Hepatocelular/epidemiologia , Guanina/análogos & derivados , Antígenos E da Hepatite B/sangue , Hepatite B Crônica/complicações , Hepatite B Crônica/tratamento farmacológico , Neoplasias Hepáticas/epidemiologia , Adulto , Estudos de Coortes , Feminino , Grécia/epidemiologia , Guanina/uso terapêutico , Humanos , Incidência , Lamivudina/uso terapêutico , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Medição de Risco , Resultado do Tratamento
8.
Hippokratia ; 18(1): 57-64, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25125954

RESUMO

BACKGROUND AND AIM: Patients with genotype 4 (G4) chronic hepatitis C (CHC) are considered a difficult to treat population, although current data on G4 treatment responsiveness and duration are controversial. Greece represents a country with an intermediate prevalence of G4 infections, offering an opportunity to compare treatment outcomes by genotype and to identify potential prognostic factors for sustained virologic response (SVR). METHODS: All CHC patients from the HepNet.Greece, an ongoing nationwide cohort study on viral hepatitis, with known hepatitis C virus (HCV) genotype who received treatment with Peg-IFNa and ribavirin were analyzed. RESULTS: From 4443 patients, 951 (61.7% males, 78.4% Greeks, median age 40.6 years, 10% cirrhosis) fulfilled the inclusion criteria. G4 was found in 125 (13.1%) patients. Genotype distribution was not significantly different between Greeks and immigrants. Patients with G4 had similar odds of SVR compared to G1 but significantly lower compared to G2/G3. Age, treatment discontinuation, presence of cirrhosis and previous history of HCV-treatment were associated with lower probabilities of SVR. Ethnicity did not affect SVR for all genotypes while response to treatment was similar between Greek and Egyptian patients groups (35.7% vs 40.9%, p=0.660%) with G4 infection. The relation between SVR and genotype did not substantially change after adjustment for age, gender, cirrhosis, treatment interruption and history of HCV-treatment. CONCLUSIONS: The findings of this large cohort of CHC patients with a well balanced genotype distribution further supports the idea of considering G4 as a difficult to treat genotype. Further investigation is needed to identify genotype specific prognostic factors.

9.
Psychiatriki ; 24(4): 288-97, 2013.
Artigo em Grego Moderno | MEDLINE | ID: mdl-24486977

RESUMO

Depression and anxiety disorders are the two most common mental health problems seen in the primary care and the general hospital settings. They are both associated with poorer patient functioning, worse quality of life, more frequent utilization of health services, and higher health care costs. However, detection rates of depression and anxiety by non-mental health specialists remain very low, while most of the proposed screening tools are rather not practical and therefore they have not been widely used in practice. Over the last two decades, ultra-short tools including one to three questions have been developed and suggested as case-finding methods and their sensitivity and specificity have been investigated. We reviewed all the ultra-short screening tools for depression and anxiety and the existing evidence on their accuracy in detecting major depression and anxiety disorders. Two simple screening questions for depression, about depressed mood and loss of interest or pleasure in doing things, have been repeatedly applied in primary care settings and found to have satisfactory sensitivity but low specificity. The addition of a third question inquiring if help is needed to the two screening questions for depression improves the specificity, however on the cost of reducing the sensitivity of the method. Screening for depression using only one of these questions alone was found to be less accurate strategy than the two or three question tests. The Patient Health Questionnaire-2 (PHQ-2) includes the same two depression-questions with rating scale answer choices and it was found to be more accurate than the two question test with dichotomous (yes or no) answers. Ultra-short screening strategies for depression in older people were found to have acceptable levels of accuracy, while in patients with cancer the two question tests had higher sensitivity and specificity than in other patient groups. According to the existing data, the Generalized Anxiety Disorder-2 (GAD-2) questionnaire, which includes two questions on "feeling nervous, anxious or on edge" and "not being able to stop or control worrying" appears to have acceptable accuracy in identifying clinically significant anxiety. We concluded that there is sufficient evidence on the suitability of the ultra-short screening instruments for depression and anxiety -especially the PHQ-2, the GAD-2 and their combination, the PHQ-4- for use in epidemiological studies. In primary and secondary care settings, the ultra-short tools can be used only as an initial screening method but diagnosis made by specially-trained clinicians or mental health specialists is warranted for patients who initially screen positive.


Assuntos
Ansiedade/diagnóstico , Depressão/diagnóstico , Transtorno Depressivo/diagnóstico , Inquéritos e Questionários , Ansiedade/psicologia , Depressão/psicologia , Transtorno Depressivo/psicologia , Feminino , Humanos , Pessoa de Meia-Idade , Escalas de Graduação Psiquiátrica , Sensibilidade e Especificidade
10.
J Chemother ; 24(1): 38-47, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22546723

RESUMO

OBJECTIVE: To evaluate the long-term effects of different boosted protease inhibitors (bPIs) or non-nucleoside reverse transcriptase inhibitors (NNRTIs)-based antiretroviral regimens on lipid levels in HIV seropositive individuals who have not received lipid-lowering agents. METHODS: Data consisted of 595 patients participating in the population-based Athens Multicenter Cohort Study who were consistently followed up during 1996-2008. RESULTS: In naïve patients, lipid parameters increased sharply during the first 3 months of antiretroviral therapy and reached a plateau level approximately 6-9 months after therapy initiation. The plateau levels remained almost stable for up to 3.5 years. In general, bPIs exerted a more pronounced effect compared to NNRTIs. CONCLUSIONS: The administration of PI- or NNRTI-based regimens especially in naïve but also in unboosted PI experienced patients provoked a sharp increase in lipid levels that remained stable in higher levels for more than 3 years.


Assuntos
Terapia Antirretroviral de Alta Atividade , Infecções por HIV/sangue , Infecções por HIV/tratamento farmacológico , Inibidores da Protease de HIV/uso terapêutico , HIV/efeitos dos fármacos , Lipídeos/análise , Inibidores da Transcriptase Reversa/uso terapêutico , Adolescente , Adulto , Estudos de Coortes , Feminino , Grécia/epidemiologia , Infecções por HIV/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
11.
Hippokratia ; 15(1): 26-31, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21607032

RESUMO

BACKGROUND AND AIMS: Hepatitis C virus (HCV) infection is an important health problem worldwide. The aim of the study is to describe the baseline characteristics and possible epidemiological changes of the patients with chronic HCV infection included in a nationwide Greek study. PATIENTS AND METHODS: two thousand eight hundred seventeen (2817) patients, followed-up at 20 hepatology centres throughout Greece between the years 1997 and 2006 were enrolled in the study. RESULTS: Intravenous drug use (IDU) and history of blood transfusion prior to 1992 was reported in 30.7% and 22.6% of our patients, respectively. In 1865 (66.2%) patients with known genotypes, the distribution for genotype 1, 2, 3 and 4 was 45.1%, 7%, 34% and 13.9% respectively. Genotype 1 was more common in older people, in women (55.9% p<0.001) and patients with transfusion-related hepatitis (61.6% p<0.001). Genotype 3 was more common in younger patients, in men (43% p<0.001) and in IDUs (63.3% p<0.001). A significant reduction of transfusion-related hepatitis C incidence (p<0.001) in conjunction with the proportion of genotype 1 (p<0.001) was observed during the last three decades while an increase in IDU infected patients and genotype 3 was detected. CONCLUSIONS: Our study showed a significant change in HCV genotype distribution and source of HCV infection during the last three decades and under that scope, urgent actions are needed in order to control the spread of HCV infection.

12.
J Epidemiol Community Health ; 63(12): 960-6, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19648130

RESUMO

BACKGROUND: The temporal pattern of effects of summertime ozone (O(3)) in total, cardiovascular and respiratory mortality were investigated in 21 European cities participating in the APHEA-2 (Air Pollution and Health: a European Approach) project, which is fundamental in determining the importance of the effect in terms of life loss. METHODS: Data from each city were analysed separately using distributed lag models with up to 21 lags. City-specific air pollution estimates were regressed on city-specific covariates to obtain overall estimates and to explore sources of possible heterogeneity. RESULTS: Stronger effects on respiratory mortality that extend to a period of 2 weeks were found. A 10 microg/m(3) increase in O(3) was associated with a 0.36% (95% CI -0.21% to 0.94%) increase in respiratory deaths for lag 0 and with 3.35% (95% CI 1.90% to 4.83%) for lags 0-20. Significant adverse health effects were found of summer O(3) (June-August) on total and cardiovascular mortality that persist up to a week, but are counterbalanced by negative effects thereafter. CONCLUSIONS: The results indicate that studies on acute health effects of O(3) using single-day exposures may have overestimated the effects on total and cardiovascular mortality, but underestimated the effects on respiratory mortality.


Assuntos
Exposição Ambiental/efeitos adversos , Mortalidade , Oxidantes Fotoquímicos/efeitos adversos , Ozônio/efeitos adversos , Estações do Ano , Doenças Cardiovasculares/mortalidade , Causas de Morte , Exposição Ambiental/análise , Europa (Continente)/epidemiologia , Humanos , Oxidantes Fotoquímicos/análise , Ozônio/análise , Doenças Respiratórias/mortalidade , Conglomerados Espaço-Temporais
13.
Aliment Pharmacol Ther ; 29(10): 1121-30, 2009 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-19222410

RESUMO

BACKGROUND: Interferon (IFN-alpha)-based regimens have been used with varying success in the treatment of chronic hepatitis C (CHC) for over two decades. The effect of such treatments on the natural course of CHC has been evaluated in small clinical trials with conflicting results. AIM: To investigate the natural course of IFNalpha-based-treated and untreated patients with CHC by analysing data from the HEPNET.GREECE study. METHODS: We retrospectively analysed 1738 patients from 25 Greek Centres (median age 40.1; males 57.6%; cirrhosis 9.2%), 734 untreated and 993 treated with IFNalpha-based regimens [44.7% sustained viral response (SVR)], followed-up for median 25.2 and 46.8 months, respectively. RESULTS: During follow-up, 48 patients developed liver decompensation and 24 HCC. Older age was significantly related to disease progression (HR = 2.6 per 10 years of increasing age). Stratified by baseline cirrhosis, Cox analysis showed that patients with SVR, but not without SVR, had significantly lower hazard for events compared with nontreated patients (HR = 0.16; P < 0.001), whereas the detrimental effect of older age remained highly significant. Separate group analysis demonstrated that in cirrhosis, the beneficial effect of treatment was evident even without SVR. Treatment effect interacted significantly with age, indicating that older patients, mainly noncirrhotic, gained the most benefit. CONCLUSIONS: IFNalpha-based treatment does alter the natural course of CHC. A protective effect is mostly present in patients with SVR, but older patients, at higher risk of events, gain the greatest benefit. In established cirrhosis, treatment carries a protective effect even among those without SVR.


Assuntos
Antivirais/uso terapêutico , Hepatite C Crônica/tratamento farmacológico , Interferon-alfa/uso terapêutico , Adulto , Idoso , Relação Dose-Resposta a Droga , Métodos Epidemiológicos , Feminino , Grécia , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Tempo , Resultado do Tratamento
14.
Stat Med ; 25(24): 4164-78, 2006 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-16991105

RESUMO

A major statistical challenge in air pollution and health time-series studies is to adequately control for confounding effects of time-varying covariates. Daily health outcome counts are most commonly analysed by Poisson regression models, adjusted for overdispersion, with air pollution levels included as a linear predictor and smooth functions for calendar time and weather variables to adjust for time-varying confounders. Various smoothers have been used so far, but the optimal strategy for choosing smoothers and their degree of smoothing remains controversial. In this work, we evaluate the performance of various smoothers with different criteria for choosing the degree of smoothing in terms of bias and efficiency of the air pollution effect estimate in a simulation study. The evaluated approaches were also applied to real mortality data from 22 European cities. The simulation study imitated a multi-city study. Data were generated from a fully parametric model. Model selection methods which optimize prediction may lead to increased biases in the air pollution effect estimate. Minimization of the absolute value of the sum of the partial autocorrelation function of the model's residuals (PACF), as a criterion to choose the degree of smoothness, gave the smallest biases. The penalized splines (PS) method with a large number of effective dfs (e.g. 8-12 per year) could be used as the basic, relatively conservative, analysis whereas the PS and natural splines in combination with PACF could be applied to provide a reasonable range of the effect estimate.


Assuntos
Poluição do Ar/análise , Interpretação Estatística de Dados , Saúde Pública/métodos , Poluição do Ar/efeitos adversos , Simulação por Computador , Europa (Continente) , Humanos , Estudos Multicêntricos como Assunto , Material Particulado/efeitos adversos , Material Particulado/análise , Distribuição de Poisson , Estações do Ano , Fatores de Tempo , População Urbana
15.
Eur Respir J ; 27(6): 1129-38, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16540496

RESUMO

The short-term effects of nitrogen dioxide (NO(2)) on total, cardiovascular and respiratory mortality in 30 European cities participating in the Air Pollution on Health: a European Approach (APHEA)-2 project were investigated. The association was examined using hierarchical models implemented in two stages. In the first stage, data from each city were analysed separately, whereas in the second stage, the city-specific air pollution estimates were regressed on city-specific covariates to obtain overall estimates and to explore sources of possible heterogeneity. A significant association of NO(2) with total, cardiovascular and respiratory mortality was found, with stronger effects on cause-specific mortality. There was evidence of confounding in respiratory mortality with black smoke and sulphur dioxide. The effect of NO(2) on total and cardiovascular mortality was observed mainly in western and southern European cities, and was larger when smoking prevalence was lower and household gas consumption was higher. The effect of NO(2) on respiratory mortality was higher in cities with a larger proportion of elderly persons in the population and higher levels of particulate matter with a 50% cut-off aerodynamic diameter of 10 mum. The results of this large study are consistent with an independent effect of nitrogen dioxide on mortality, but the role of nitrogen dioxide as a surrogate of other unmeasured pollutants cannot be completely ruled out.


Assuntos
Poluentes Atmosféricos/toxicidade , Doenças Cardiovasculares/mortalidade , Causas de Morte , Dióxido de Nitrogênio/toxicidade , Doenças Respiratórias/mortalidade , População Urbana/estatística & dados numéricos , Comparação Transcultural , Poeira , Europa (Continente)/epidemiologia , Humanos , Modelos Estatísticos , Fumaça , Fumar/efeitos adversos , Fumar/mortalidade , Estatística como Assunto , Dióxido de Enxofre/toxicidade
16.
Aliment Pharmacol Ther ; 23(6): 787-95, 2006 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-16556181

RESUMO

BACKGROUND: Factors that predict response and breakthrough phenomenon to lamivudine monotherapy in patients with HBeAg-negative chronic hepatitis B have not been well defined. AIM: To determine pre-treatment and on treatment variables that predict initial response and breakthrough in patients with HBeAg-negative chronic hepatitis B receiving long-term lamivudine. METHODS: Seventy-nine patients, with chronic HBeAg-negative hepatitis B, who received lamivudine for a median of 31 months were included in the study. RESULTS: Initial virologic and biochemical response was observed in 73 (92%) and 70 (89%) patients, respectively, while 34 (47%) and 15 (21%) patients developed virological and biochemical breakthrough, respectively. High levels of necroinflammation in liver biopsy were associated with a higher probability of initial virological and biochemical response. Patients with pre-treatment serum hepatitis B virus DNA concentrations of more than 10(6) copies/mL were three times more likely to develop virologic breakthrough. Two patients died, one with baseline cirrhosis because of liver failure during biochemical breakthrough while the second death was liver and treatment unrelated. CONCLUSIONS: In HBeAg-negative chronic hepatitis B, initial response to lamivudine therapy is associated with necroinflammation, while baseline serum hepatitis B virus DNA exceeding 10(6) copies/mL is a strong predictor for breakthrough because of drug-resistant mutations. Severe complications are uncommon and are associated with biochemical breakthrough and pre-existing cirrhosis.


Assuntos
Antivirais/uso terapêutico , Antígenos E da Hepatite B/imunologia , Hepatite B Crônica/tratamento farmacológico , Lamivudina/uso terapêutico , Adolescente , Adulto , Idoso , DNA Viral/análise , Farmacorresistência Viral , Feminino , Vírus da Hepatite B/efeitos dos fármacos , Vírus da Hepatite B/genética , Vírus da Hepatite B/imunologia , Hepatite B Crônica/imunologia , Hepatite B Crônica/virologia , Humanos , Fígado/imunologia , Fígado/patologia , Assistência de Longa Duração , Masculino , Pessoa de Meia-Idade , Mutação , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Resultado do Tratamento
17.
J Viral Hepat ; 12(5): 543-50, 2005 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16108772

RESUMO

SUMMARY: The epidemic of hepatitis C virus (HCV) infection is a major public health issue. We conducted a comprehensive analysis to estimate future HCV-related morbidity and mortality, using a model which is the first to take into account currently available treatments. We reconstructed the incident infections per year in the past that progressed to chronic hepatitis C (CHC) in Greece. Then, the natural history of the disease was simulated in subcohorts of newly infected subjects in the presence or absence of treatment using yearly estimates of the number of treated patients obtained from national databases. Annual estimates of the incidence and prevalence of CHC by fibrosis stage, hepatocellular carcinoma (HCC) and mortality were obtained up to 2030. The current proportion of naïve CHC patients receiving treatment in Greece is 1.2% per year. Treatment of 1.2-10% of naïve CHC patients per year would reduce the cumulative number of incident cirrhosis and HCC cases from 2002 to 2030 by 10.8-39.4% and 12.8-39.8%, respectively and decrease the number of prevalent cirrhosis and HCC cases in 2030 by approximately 17-48% compared with the number estimated under the assumption of no treatment. Approximately 17 cirrhosis cases or six HCC cases or 10 premature deaths would be prevented for every 100 treated patients. However, the prevalent cirrhotic/HCC cases because of HCV and HCV-related deaths would not plateau until 2030. Despite the introduction of effective treatment, HCV-related morbidity and mortality will likely increase during the next 20-30 years in Greece. Intensive primary prevention efforts coupled with increased access to the currently available treatments are necessary to control the chronic consequences of HCV epidemic.


Assuntos
Carcinoma Hepatocelular/epidemiologia , Hepatite C Crônica/complicações , Cirrose Hepática/epidemiologia , Carcinoma Hepatocelular/etiologia , Carcinoma Hepatocelular/virologia , Progressão da Doença , Previsões , Grécia/epidemiologia , Hepatite C Crônica/transmissão , Humanos , Incidência , Cirrose Hepática/etiologia , Cirrose Hepática/virologia , Falência Hepática/epidemiologia , Falência Hepática/etiologia , Modelos Estatísticos , Prevalência , Probabilidade
18.
Haemophilia ; 11(4): 360-5, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16011588

RESUMO

AIM: The study aims to describe the course of HIV-1 infection in the pre- and post-HAART period in a cohort of HIV+ haemophilia patients followed up for up to 21 years. METHODS: The cohort includes 158 haemophilic men with known seroconversion dates followed up prospectively for a median time of 12 and 5.7 years in the pre- (1980-96) and post-HAART period (1997-2003), respectively. RESULTS: The risk of developing AIDS was lowered by 56% in the post- as compared to the pre-HAART period. Of the 158 patients 69 developed AIDS in the pre-HAART period while of the 59 subjects still alive and AIDS free on 1/1/1997 six developed AIDS. The rate of PCP (12.0 cases per 1000 person-years) and NHL (5.4 cases per 1000 person-years), the most common causes of AIDS diagnosis in the pre-HAART era, were remarkably reduced in the post-HAART era (both rates: 2.8 cases per 1000 person-years). On the contrary, the corresponding risk for non-AIDS deaths was fourfold increased in the post-HAART period. Of the 38 non-AIDS related deaths in both periods, 13 occurred post-HAART. The predominant cause of non-AIDS mortality in both periods was end-stage liver disease (ESLD) (7 pre- and 4 post-HAART). The rate of non-AIDS related cancers was also increased during the post-HAART period. CONCLUSION: In this haemophilia cohort the risk of AIDS has substantially reduced in the post-HAART period, but the rate of non-AIDS mortality tended to increase. Among haemophilia subjects, due to the high rates of HCV/HIV coinfection, ESLD, the predominant cause of non-AIDS mortality, will become an increasingly important clinical problem.


Assuntos
Terapia Antirretroviral de Alta Atividade/métodos , Infecções por HIV/complicações , HIV-1 , Hemofilia A/complicações , Síndrome da Imunodeficiência Adquirida/epidemiologia , Síndrome da Imunodeficiência Adquirida/etiologia , Síndrome da Imunodeficiência Adquirida/mortalidade , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Causas de Morte , Criança , Pré-Escolar , Progressão da Doença , Grécia/epidemiologia , Infecções por HIV/tratamento farmacológico , Infecções por HIV/epidemiologia , Hemofilia A/mortalidade , Humanos , Incidência , Lactente , Falência Renal Crônica/complicações , Falência Renal Crônica/mortalidade , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Fatores de Risco
19.
J Viral Hepat ; 11(4): 366-74, 2004 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15230860

RESUMO

In this study, a comprehensive methodology for modelling the hepatitis C virus (HCV) epidemic is proposed to predict the future disease burden and assess whether the recent decline in the incidence of HCV may affect the future occurrence of cirrhosis and hepatocellular carcinoma (HCC) cases. Using the prevalence of HCV, the distribution of chronic hepatitis C (CHC) patients within the various transmission groups and their infection-onset times, it was possible to reconstruct the incident infections per year in the past that progressed to CHC in Greece. The natural history of the disease was simulated in subcohorts of newly infected subjects using transition probabilities derived either empirically between fibrosis stages 0-4 or from literature review. Annual estimates of the incidence and prevalence of CHC by fibrosis stage, HCC and mortality in Greece were obtained up to 2030. HCV incidence peaked in the late 1980s at five new infections/10,000 person-years. Under the assumption of 20-100% decline in HCV incidence after 1990, the cumulative number of incident cirrhosis and HCC cases from 2002-2030 was projected to be lower by 9.6-48.2% and 5.9-29.5%, respectively, than that estimated under the assumption of no decline. However, the prevalent cirrhotic/HCC cases and HCV-related deaths are predicted to decline in the next 30 years only under the assumption of complete elimination of new HCV infections after 1990. Despite the progress in the reduction of HCV transmission, primary prevention does not seem adequate to reverse the rise in the incidence of cirrhosis and HCC.


Assuntos
Carcinoma Hepatocelular/epidemiologia , Hepatite C Crônica/complicações , Hepatite C Crônica/epidemiologia , Cirrose Hepática/epidemiologia , Modelos Estatísticos , Carcinoma Hepatocelular/virologia , Progressão da Doença , Previsões , Grécia/epidemiologia , Hepatite C Crônica/transmissão , Humanos , Incidência , Cirrose Hepática/virologia , Falência Hepática/epidemiologia , Falência Hepática/etiologia , Prevalência , Probabilidade
20.
Occup Environ Med ; 60(12): 977-82, 2003 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-14634192

RESUMO

BACKGROUND: Several recent studies have reported significant health effects of air pollution even at low levels of air pollutants, but in most of these studies linear non-threshold relations were assumed. AIMS: To investigate the NO2 mortality dose-response association in nine cities participating in the APHEA-2 project using two different methods: the meta-smooth and the cubic spline method. METHODS: The meta-smooth method developed by Schwartz and Zanobetti is based on combining individual city non-parametric smooth curves; the cubic spline method developed within the APHEA-2 project combines individual city estimates of cubic spline shaped dose-response relations. The meta-smooth method is easier and faster to implement, but the cubic spline method is more flexible for further investigation of possible heterogeneity in the dose-response curves among cities. RESULTS: In the range of the pollutant common to all cities the two methods gave similar and comparable curves. Using the cubic spline method it was found that smoking prevalence acts as an effect modifier with larger NO2 effects on mortality at lower smoking prevalence. CONCLUSIONS: The NO2-mortality association in the cities included in the present analysis, could be adequately estimated using the linear model. However, investigation of the city specific dose-response curves should precede the application of linear models.


Assuntos
Poluentes Atmosféricos/toxicidade , Exposição Ambiental/efeitos adversos , Mortalidade , Dióxido de Nitrogênio/toxicidade , Saúde da População Urbana , Poluentes Atmosféricos/análise , Algoritmos , Relação Dose-Resposta a Droga , Exposição Ambiental/análise , Humanos , Modelos Lineares , Dióxido de Nitrogênio/administração & dosagem , Dióxido de Nitrogênio/análise
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