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2.
J Sex Med ; 2024 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-39034042

RESUMO

BACKGROUND: Vulvodynia impacts up to 8% of women by age 40, and these women may have a more compromised immune system than women with no vulvar pain history. AIM: Given that psychiatric morbidity is associated with vulvodynia and is known to activate immune inflammatory pathways in the brain and systemically, we sought to determine whether the association between psychiatric morbidity and vulvar pain was independent of or dependent upon the presence of immune-related conditions. METHODS: Women born in Sweden between 1973 and 1996 with localized provoked vulvodynia (N76.3) and/or vaginismus (N94.2 or F52.5) diagnosed between 2001 and 2018 were matched to two women from the same birth year with no vulvar pain. International Statistical Classification of Diseases and Related Health Problems (ICD-9 or -10 codes) were used to identify women with a history of depression, anxiety, attempted suicide, neurotic disorders, stress-related disorders, behavioral syndromes, personality disorders, psychotic disorders, or chemical dependencies, as well as a spectrum of immune-related conditions. The Swedish National Prescribed Drug Register was used to identify women with filled prescriptions of antidepressants or anxiolytics. OUTCOMES: Vulvodynia, vaginismus, or both were outcomes assessed in relation to psychiatric morbidity. RESULTS: Women with vulvodynia, vaginismus, or both, relative to those without vulvar pain, had adjusted odds ratios between 1.4 and 2.3, with CIs highly compatible with harmful effects. When we assessed women with and those without a lifetime history of immune-related conditions separately, we also observed elevated odds ratios in both groups for mood, anxiety, and neurotic and stress disorders. CLINICAL IMPLICATIONS: Documenting psychiatric impairment as a cause or consequence of vulvodynia is critical in clinical practice because psychiatric conditions may impact treatment efficacy. STRENGTHS AND LIMITATIONS: Strengths of this study include a data source that represents the entire population of women in Sweden that is known to be highly accurate because Sweden provides universal healthcare. Limitations include difficulty in making an accurate assessment of temporality between psychiatric morbidity and the first onset of vulvar pain. In addition, because Swedish registry data have limited information on lifestyle, behavioral, and anthropomorphic factors such as smoking, diet, physical activity, and obesity, these conditions could not be assessed as confounders of psychiatric morbidity and vulvar pain. CONCLUSIONS: Immune pathways by which women with psychiatric conditions increase their risk of vulvar pain could be independent from other immune pathways.

3.
Clin Epidemiol ; 16: 501-512, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39081306

RESUMO

Background: Observational studies of SARS-CoV-2 vaccine effectiveness are prone to confounding, which can be illustrated using negative control methods. Methods: Nationwide population-based cohort study including two cohorts of Danish residents 60-90 years of age matched 1:1 on age and sex: A vaccinated and a non-vaccinated cohort, including 61052 SARS-CoV-2 vaccinated individuals between 1 March and 1 July 2021 and 61052 individuals not vaccinated preceding 1 July 2021. From these two cohorts, we constructed negative control cohorts of individuals diagnosed with SARS-CoV-2 infection or acute myocardial infarction, stroke, cancer, low energy fracture, or head-trauma. Outcomes were SARS-CoV-2 infection, negative control outcomes (eg, mammography, prostate biopsy, operation for cataract, malignant melanoma, examination of eye and ear), and death. We used Cox regression to calculate adjusted incidence and mortality rate ratios (aIRR and aMRR). Results: Risks of SARS-CoV2 infection and all negative control outcomes were elevated in the vaccinated population, ranging from an aIRR of 1.15 (95% CI: 1.09-1.21) for eye examinations to 3.05 (95% CI: 2.24-4.14) for malignant melanoma. Conversely, the risk of death in the SARS-CoV-2 infected cohort and in all negative control cohorts was lower in vaccinated individuals, ranging from an aMRR of 0.23 (95% CI: 0.19-0.26) after SARS-CoV-2 infection to 0.50 (95% CI: 0.37-0.67) after stroke. Conclusion: Our findings indicate that observational studies of SARS-CoV-2 vaccine effectiveness may be subject to substantial confounding. Therefore, randomized trials are essential to establish vaccine efficacy after the emergence of new SARS-CoV-2 variants and the rollout of multiple booster vaccines.


Why was this study done: : After the emergence of new SARS-CoV-2 variants and the rollout of multiple booster SARS-CoV-2 vaccines, the impact of vaccination on risk of SARS-CoV-2 infection and death after the infection has mainly been explored in observational studies. We used negative control methods to investigate whether confounding affects the results of observational SARS-CoV-2 vaccine effectiveness studies. Findings: : We used Danish registry data obtained during the SARS-CoV-2 vaccine roll-out to conduct a nationwide, matched population-based cohort study of Danish residents 60­90 years in which we compared vaccinated individuals with non-vaccinated individuals. Compared with unvaccinated individuals, vaccinated individuals had increased risks of SARS-CoV2 infection but also had increased risks of all negative control outcomes (mammography, prostate biopsy, operation for cataract, malignant melanoma, examination of eye and ear). The risk of death after SARS-CoV2 infection was lower in the vaccinated cohort, as was the risk of death after acute myocardial infarction, stroke, cancer, low energy fracture, and head-trauma. Meaning: : The negative control methods indicate that observational studies of SARS-CoV-2 vaccine effectiveness may be prone to substantial confounding which may impact the observed associations. This bias may both lead to underestimation of vaccine effectiveness (increased risk of SARS-CoV2 infection among vaccinated individuals) and overestimation of the vaccine effectiveness (decreased risk of death after of SARS-CoV2 infection among vaccinated individuals). Our results highlight the need for randomized vaccine efficacy studies after the emergence of new SARS-CoV-2 variants and the rollout of multiple booster vaccines.

4.
AIDS ; 38(8): 1198-1205, 2024 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-38814712

RESUMO

OBJECTIVE: To estimate the relative rate of all-cause mortality amongst those on antiretroviral treatment (ART) with a history of interruptions compared with those with no previous interruptions in care. DESIGN: Retrospective cohort study. METHODS: We used data from four South African cohorts participating in the International epidemiology Databases to Evaluate AIDS Southern Africa collaboration. We included adults who started ART between 2004 and 2019. We defined a care interruption as a gap in contact longer than 180 days. Observation time prior to interruption was allocated to a 'no interruption' group. Observation time after interruption was allocated to one of two groups based on whether the first interruption started before 6 months of ART ('early interruption') or later ('late interruption'). We used Cox regression to estimate hazard ratios. RESULTS: Sixty-three thousand six hundred and ninety-two participants contributed 162 916 person-years of observation. There were 3469 deaths. Most participants were female individuals (67.4%) and the median age at ART initiation was 33.3 years (interquartile range: 27.5-40.7). Seventeen thousand and eleven (26.7%) participants experienced care interruptions. Those resuming ART experienced increased mortality compared with those with no interruptions: early interrupters had a hazard ratio of 4.37 (95% confidence interval (CI) 3.87-4.95) and late interrupters had a hazard ratio of 2.74 (95% CI 2.39-3.15). In sensitivity analyses, effect sizes were found to be proportional to the length of time used to define interruptions. CONCLUSION: Our findings highlight the need to improve retention in care, regardless of treatment duration. Programmes to encourage return to care also need to be strengthened.


Assuntos
Infecções por HIV , Humanos , Feminino , Masculino , Estudos Retrospectivos , Adulto , Infecções por HIV/tratamento farmacológico , Infecções por HIV/mortalidade , África do Sul/epidemiologia , Fármacos Anti-HIV/uso terapêutico , Fármacos Anti-HIV/administração & dosagem , Pessoa de Meia-Idade , Antirretrovirais/uso terapêutico
6.
Am J Epidemiol ; 2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38754869

RESUMO

We spend a great deal of time on confounding in our teaching, in our methods development and in our assessment of study results. This may give the impression that uncontrolled confounding is the biggest problem that observational epidemiology faces, when in fact, other sources of bias such as selection bias, measurement error, missing data, and misalignment of zero time may often (especially if they are all present in a single study) lead to a stronger deviation from the truth. Compared to the amount of time we spend teaching how to address confounding in a data analysis, we spend relatively little time teaching methods for simulating confounding (and other sources of bias) to learn their impact and develop plans to mitigate or quantify the bias. We review a paper by Desai et al that uses simulation methods to quantify the impact of an unmeasured confounder when it is completely missing or when a proxy of the confounder is measured. We use this article to discuss how we can use simulations of sources of bias to ensure we generate better and more valid study estimates, and we discuss the importance of simulating realistic datasets with plausible bias structures to guide data collection. If an advanced life form exists outside of our current universe and they came to earth with the goal of scouring the published epidemiologic literature to understand what the biggest problem epidemiologists have, they would quickly discover that the limitations section of publications would provide them with all the information they needed. And most likely what they would conclude is that the biggest problem that we face is uncontrolled confounding. It seems to be an obsession of ours.

7.
Aliment Pharmacol Ther ; 59(12): 1551-1558, 2024 06.
Artigo em Inglês | MEDLINE | ID: mdl-38597407

RESUMO

BACKGROUND: Paediatric-onset immune-mediated inflammatory diseases (pIMID) show more aggressive phenotypes than when diagnosed in adults. However, data on mortality are often extrapolated from adult studies. AIM: To estimate the effect of pIMID on mortality. METHODS: In a population-based cohort study using the nationwide Danish healthcare registers, we included all patients diagnosed with pIMID in Denmark from 1980 to 2018. PIMID were defined as ICD codes indicative of autoimmune hepatitis, primary sclerosing cholangitis, Crohn's disease, ulcerative colitis, juvenile idiopathic arthritis, lupus erythematosus, or vasculitis registered before age 18 years. All-cause mortality was the primary outcome; cause-specific mortality was the secondary outcome. We used Cox survival analysis to estimate hazard ratios (HR), and Aalen survival analysis to estimate rate differences. RESULTS: We included 11,581 individuals diagnosed with pIMID and 99,665 reference individuals, accounting for 1,371,994 person-years of follow-up. Median and interquartile (IQR) age at diagnosis was 12.6 (7.9-15.9) years. During follow-up, 152 patients with pIMID and 316 reference individuals died; adjusted HR (aHR) was 3.8 (95% confidence interval [CI] 3.1-4.7). This corresponded to 6.9 (95% CI: 5.3-8.5) additional deaths per 10,000 person-years. The strongest associations were found for gastrointestinal diseases (aHR 22.8; 95% CI 9.6-64.1), gastrointestinal cancers (aHR 19.2; 95% CI 5.0-74.2) and lymphoproliferative disorders (aHR 6.8; 95% CI 2.8-16.8). CONCLUSION: Patients diagnosed with pIMID have a fourfold higher risk of mortality when followed into early adulthood compared with reference individuals. This underlines the severe disease course of pIMID and highlights the need for multidisciplinary care.


Assuntos
Sistema de Registros , Humanos , Masculino , Feminino , Criança , Adolescente , Dinamarca/epidemiologia , Estudos de Coortes , Fatores de Risco , Idade de Início , Pré-Escolar , Causas de Morte , Inflamação/mortalidade
8.
Pharmacoepidemiol Drug Saf ; 33(5): e5796, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38680093

RESUMO

PURPOSE: Use of real-world data (RWD) for external controls added to single-arm trials (SAT) is increasingly prevalent in regulatory submissions. Due to inherent differences in the data-generating mechanisms, biases can arise. This paper aims to illustrate how to use quantitative bias analysis (QBA). METHODS: Advanced non-small cell lung cancer (NSCLC) serves as an example, where many small subsets of patients with molecular tumor subtypes exist. First, some sources of bias that may occur in oncology when comparing RWD to SAT are described. Second, using a hypothetical immunotherapy agent, a dataset is simulated based on expert input for survival analysis of advanced NSCLC. Finally, we illustrate the impact of three biases: missing confounder, misclassification of exposure, and outcome evaluation. RESULTS: For each simulated scenario, bias was induced by removing or adding data; hazard ratios (HRs) were estimated applying conventional analyses. Estimating the bias-adjusted treatment effect and uncertainty required carefully selecting the bias model and bias factors. Although the magnitude of each biased and bias-adjusted HR appeared moderate in all three hypothetical scenarios, the direction of bias was variable. CONCLUSION: These findings suggest that QBA can provide an intuitive framework for bias analysis, providing a key means of challenging assumptions about the evidence. However, the accuracy of bias analysis is itself dependent on correct specification of the bias model and bias factors. Ultimately, study design should reduce bias, but QBA allows us to evaluate the impact of unavoidable bias to assess the quality of the evidence.


Assuntos
Viés , Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/terapia , Projetos de Pesquisa , Ensaios Clínicos como Assunto/métodos , Simulação por Computador , Análise de Sobrevida , Imunoterapia/métodos
9.
ASAIO J ; 70(3): 239-240, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38411926
10.
ASAIO J ; 70(7): 625-632, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38300884

RESUMO

There has been an increase in the use of extracorporeal membrane oxygenation (ECMO) to bridge critically ill patients to lung transplant (LTX). This study evaluates how ambulatory status on ECMO affected waitlist and post-LTX outcomes. The United Network of Organ Sharing (UNOS) database was queried for patients aged of greater than or equal to 18 years and between 2016 and 2021 to identify pre-LTX patients supported by ECMO. The patients were classified in venous-arterial (VA) ECMO and veno-venous (VV) ECMO cohorts and further classified as ambulatory (AMB) and non-AMB (nAMB). Each cohort was controlled against the non-ECMO patients. Univariate statistical tests, as well as Kaplan-Meier survival curves, were used for analysis. The 90 day waitlist survival was the highest among the non-ECMO group (96%), but both AMB VV and VA groups had superior survival compared to the nAMB group (85% vs. 75%, 78% vs. 65%, p < 0.01). After adjusting for the median lung allocation score (LAS) (88) in the VV ECMO group, the waitlist survival was superior in the AMB VV ECMO compared to those not on ECMO (86% vs. 78%, p > 0.01). The 1 year post-LTX survival between non-ECMO and AMB VV ECMO was comparable (88% vs. 88%, p = 0.66). Ambulating patients or use of physical therapy while on ECMO can help improve lung transplant outcomes.


Assuntos
Oxigenação por Membrana Extracorpórea , Transplante de Pulmão , Listas de Espera , Humanos , Oxigenação por Membrana Extracorpórea/métodos , Oxigenação por Membrana Extracorpórea/estatística & dados numéricos , Transplante de Pulmão/métodos , Transplante de Pulmão/estatística & dados numéricos , Masculino , Feminino , Pessoa de Meia-Idade , Listas de Espera/mortalidade , Adulto , Estudos Retrospectivos , Assistência Ambulatorial/estatística & dados numéricos , Assistência Ambulatorial/métodos
11.
AIDS Behav ; 28(2): 591-608, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38300475

RESUMO

Low- and middle-income countries are facing a growing burden of noncommunicable diseases (NCDs). Providing HIV treatment may provide opportunities to increase access to NCD services in under-resourced environments. We conducted a systematic review and meta-analysis to evaluate whether use of antiretroviral therapy (ART) was associated with increased screening, diagnosis, treatment, and control of diabetes, hypertension, chronic kidney disease, or cardiovascular disease among people living with HIV in sub-Saharan Africa (SSA). A comprehensive search of electronic literature databases for studies published between 01 January 2011 and 31 December 2022 yielded 26 studies, describing 13,570 PLWH in SSA, 61% of whom were receiving ART. Random effects models were used to calculate summary odds ratios (ORs) of the risk of diagnosis by ART status and corresponding 95% confidence intervals (95% CIs), where appropriate. ART use was associated with a small but imprecise increase in the odds of diabetes diagnosis (OR 1.07; 95% CI 0.71, 1.60) and an increase in the odds of hypertension diagnosis (OR 2.10, 95% CI 1.42, 3.09). We found minimal data on the association between ART use and screening, treatment, or control of NCDs. Despite a potentially higher NCD risk among PLWH and regional efforts to integrate NCD and HIV care, evidence to support effective care integration models is lacking.


Assuntos
Infecções por HIV , Programas de Rastreamento , Doenças não Transmissíveis , Humanos , África Subsaariana/epidemiologia , Fármacos Anti-HIV/uso terapêutico , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/prevenção & controle , Doenças Cardiovasculares/diagnóstico , Diabetes Mellitus/epidemiologia , Diabetes Mellitus/diagnóstico , Infecções por HIV/tratamento farmacológico , Infecções por HIV/diagnóstico , Infecções por HIV/epidemiologia , Hipertensão/tratamento farmacológico , Hipertensão/epidemiologia , Hipertensão/diagnóstico , Doenças não Transmissíveis/epidemiologia , Doenças não Transmissíveis/prevenção & controle
12.
BMC Infect Dis ; 23(1): 889, 2023 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-38114912

RESUMO

BACKGROUND: Periods of droughts can lead to decreased food security, and altered behaviours, potentially affecting outcomes on antiretroviral therapy (ART) among persons with HIV (PWH). We investigated whether decreased rainfall is associated with adverse outcomes among PWH on ART in Southern Africa. METHODS: Data were combined from 11 clinical cohorts of PWH in Lesotho, Malawi, Mozambique, South Africa, Zambia, and Zimbabwe, participating in the International epidemiology Databases to Evaluate AIDS Southern Africa (IeDEA-SA) collaboration. Adult PWH who had started ART prior to 01/06/2016 and were in follow-up in the year prior to 01/06/2016 were included. Two-year rainfall from June 2014 to May 2016 at the location of each HIV centre was summed and ranked against historical 2-year rainfall amounts (1981-2016) to give an empirical relative percentile rainfall estimate. The IeDEA-SA and rainfall data were combined using each HIV centre's latitude/longitude. In individual-level analyses, multivariable Cox or generalized estimating equation regression models (GEEs) assessed associations between decreased rainfall versus historical levels and four separate outcomes (mortality, CD4 counts < 200 cells/mm3, viral loads > 400 copies/mL, and > 12-month gaps in follow-up) in the two years following the rainfall period. GEEs were used to investigate the association between relative rainfall and monthly numbers of unique visitors per HIV centre. RESULTS: Among 270,708 PWH across 386 HIV centres (67% female, median age 39 [IQR: 32-46]), lower rainfall than usual was associated with higher mortality (adjusted Hazard Ratio: 1.18 [95%CI: 1.07-1.32] per 10 percentile rainfall rank decrease) and unsuppressed viral loads (adjusted Odds Ratio: 1.05 [1.01-1.09]). Levels of rainfall were not strongly associated with CD4 counts < 200 cell/mm3 or > 12-month gaps in care. HIV centres in areas with less rainfall than usual had lower numbers of PWH visiting them (adjusted Rate Ratio: 0.80 [0.66-0.98] per 10 percentile rainfall rank decrease). CONCLUSIONS: Decreased rainfall could negatively impact on HIV treatment behaviours and outcomes. Further research is needed to explore the reasons for these effects. Interventions to mitigate the health impact of severe weather events are required.


Assuntos
Fármacos Anti-HIV , Infecções por HIV , Adulto , Humanos , Feminino , Masculino , Contagem de Linfócito CD4 , Infecções por HIV/tratamento farmacológico , Infecções por HIV/epidemiologia , Infecções por HIV/complicações , África Austral/epidemiologia , Estudos de Coortes , África do Sul , Fármacos Anti-HIV/uso terapêutico
13.
BMC Health Serv Res ; 23(1): 1452, 2023 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-38129852

RESUMO

BACKGROUND: Research out of South Africa estimates the total unmet need for care for those with type 2 diabetes mellitus (diabetes) at 80%. We evaluated the care cascade using South Africa's National Health Laboratory Service (NHLS) database and assessed if HIV infection impacts progression through its stages. METHODS: The cohort includes patients from government facilities with their first glycated hemoglobin A1c (HbA1c) or plasma glucose (fasting (FPG); random (RPG)) measured between January 2012 to March 2015 in the NHLS. Lab-diagnosed diabetes was defined as HbA1c ≥ 6.5%, FPG ≥ 7.0mmol/l, or RPG ≥ 11.1mmol/l. Cascade stages post diagnosis were retention-in-care and glycaemic control (defined as an HbA1c < 7.0% or FPG < 8.0mmol/l or RPG < 10.0mmol/l) over 24-months. We estimated gaps at each stage nationally and by people living with HIV (PLWH) and without (PLWOH). RESULTS: Of the 373,889 patients tested for diabetes, 43.2% had an HbA1c or blood glucose measure indicating a diabetes diagnosis. Amongst those with lab-diagnosed diabetes, 30.9% were retained-in-care (based on diabetes labs) and 8.7% reached glycaemic control by 24-months. Prevalence of lab-diagnosed diabetes in PLWH was 28.6% versus 47.3% in PLWOH. Among those with lab-diagnosed diabetes, 34.3% of PLWH were retained-in-care versus 30.3% PLWOH. Among people retained-in-care, 33.8% of PLWH reached glycaemic control over 24-months versus 28.6% of PLWOH. CONCLUSIONS: In our analysis of South Africa's NHLS database, we observed that 70% of patients diagnosed with diabetes did not maintain in consistent diabetes care, with fewer than 10% reaching glycemic control within 24 months. We noted a disparity in diabetes prevalence between PLWH and PLWOH, potentially linked to different screening methods. These differences underscore the intricacies in care but also emphasize how HIV care practices could guide better management of chronic diseases like diabetes. Our results underscore the imperative for specialized strategies to bolster diabetes care in South Africa.


Assuntos
Diabetes Mellitus Tipo 2 , Infecções por HIV , Humanos , Glicemia , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/epidemiologia , Diabetes Mellitus Tipo 2/terapia , Hemoglobinas Glicadas , Infecções por HIV/diagnóstico , Infecções por HIV/epidemiologia , Infecções por HIV/terapia , África do Sul/epidemiologia
15.
Bull. W.H.O. (Online) ; 88(9): 675­680-2010. ilus
Artigo em Inglês | AIM (África) | ID: biblio-1259871

RESUMO

Objective:To estimate rates of completion of CD4+ lymphocyte testing (CD4 testing) within 12 weeks of testing positive for human immunodeficiency virus (HIV) at a large HIV/AIDS clinic in South Africa, and to identify clinical and demographic predictors for completion.Methods:In our study, CD4 testing was considered complete once a patient had retrieved the test results. To determine the rate of CD4 testing completion, we reviewed the records of all clinic patients who tested positive for HIV between January 2008 and February 2009. We identified predictors for completion through multivariate logistic regression.Findings:Of the 416 patients who tested positive for HIV, 84.6% initiated CD4 testing within the study timeframe. Of these patients, 54.3% were immediately eligible for antiretroviral therapy (ART) because of a CD4 cell count ≤ 200/µl, but only 51.3% of the patients in this category completed CD4 testing within 12 weeks of HIV testing. Among those not immediately eligible for ART (CD4 cells > 200/µl), only 14.9% completed CD4 testing within 12 weeks. Overall, of HIV+ patients who initiated CD4 testing, 65% did not complete it within 12 weeks of diagnosis. The higher the baseline CD4 cell count, the lower the odds of completing CD4 testing within 12 weeks.Conclusion:Patient losses between HIV testing, baseline CD4 cell count and the start of care and ART are high. As a result, many patients receive ART too late. Health information systems that link testing programmes with care and treatment programmes are needed


Assuntos
Síndrome da Imunodeficiência Adquirida/tratamento farmacológico , Antirretrovirais/administração & dosagem , Soropositividade para HIV/diagnóstico , Soropositividade para HIV/tratamento farmacológico , Soropositividade para HIV/imunologia , África do Sul , Organização Mundial da Saúde
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