The Healthy Participant Effect: insights and results from a population-based case-control study on breast cancer.

Agreement to participate in case-control studies has become low. Healthy participant bias resulting from differential response proportions in cases and controls can distort results; however, the magnitude of bias is difficult to assess. We investigated the effect in a large population-based case-control study on breast cancer, with a participation rate of 43.4% and 64.1% for controls and cases. We performed a mortality follow-up in 2020 for 3,813 cases and 7,335 controls recruited between 2002-2005. Standardized mortality ratios (SMR) for overall mortality and selected causes of death were estimated. The mean age at recruitment was 63.1 years. The overall mortality for controls was 0.66 times lower (95%CI 0.62-0.69) than for the reference population. For causes of death other than breast cancer, SMRs were similar in cases and controls (0.70 and 0.64). Higher education was associated with lower SMRs in both cases and controls. Options for adjusting the healthy participant bias are limited if the true risk factor distribution in the underlying population is unknown. However, a relevant bias in this particular case-control study is considered unlikely since a similar healthy participant effect was observed for both controls and cases.

Teaching hospitals and their influence on survival after valve replacement procedures: A retrospective cohort study using inverse probability of treatment weighting (IPTW).

BACKGROUND: The effect of teaching hospital status on cardiovascular surgery has been of common interest in recent decades, yet its magnitude on heart valve replacement is still a matter of debate. Given the ethical and practical unfeasibility of randomly assigning a patient to such an exposure, we use the inverse probability of treatment weighting (IPTW) to assess this marginal effect on the survival of Colombian patients who underwent a first heart valve replacement between 2016 and 2019. METHODS: A retrospective cohort study was conducted based on administrative records. The time-to-death event and cumulative incidences of death, readmission, and reoperation are presented as outcomes. An artificial sample is configured through IPTW, adjusting for sociodemographic variables, comorbidities, technique, and intervention weight. RESULTS: Of a sample of 3,517 patients, 1,051 (29.9%) were operated on in a teaching hospital. The median age was 65.0 (18.1-91.5), 38.5% of patients were ≤60, and 6.9% were ≥80. The cumulative incidences of death at 30, 90 days, and one year were 5.9%, 8%, and 10.9%, respectively. Furthermore, 23.5% of the patients were readmitted within 90 days and 3.6% underwent reintervention within one year. The odds of 30-day mortality are lower for patients operated in a teaching hospital (OR 0.51; 95% CI 0.29-0.92); however, no effect on survival was identified in terms of time-to-event of death (HR 1.07; 95%CI 0.78-1.46). CONCLUSIONS: After IPTW, the odds of 30-day mortality are lower for patients operated in a teaching hospital. There was no effect on survival, 90-day or one-year mortality, 90-day readmission, or one-year reintervention. Together, we offer an opening for investigating an exposure that has yet to be explored in Latin America with potential value to understand teaching hospitals as the essential nature of reality of an academic-clinical synergy.

Cost-effectiveness analysis of treatments for the first episode of catastrophic antiphospholipid syndrome: A study based on the catastrophic antiphospholipid syndrome registry.

BACKGROUND: Treatments for catastrophic antiphospholipid syndrome (CAPS) rose from recommendations and consensus of international experts based on case series or case reports. We aimed to evaluate the treatment scheme with the best cost-effectiveness ratio associated with lower mortality as a high-impact clinical benefit. METHODS: The CAPS Registry was used as our source of structured data on the different therapeutic strategies, their frequency, and their effectiveness (survival). Starting from around 50 different schemes, we identified those with a mortality of less than 33% within the 18 most frequently utilized. After applying the efficiency frontier method, we included two schemes to conduct a cost-effectiveness analysis from the Colombian healthcare sector perspective. Scheme 1 (Glucocorticoids + Anticoagulation + Anti-aggregation + Intravenous IgG immunoglobulin) and scheme 2 (Glucocorticoids + Anticoagulation + Anti-aggregation + Plasma exchange) were compared in terms of costs and survival. Deterministic and probabilistic sensitivity analyses (Monte Carlo simulation) were conducted to evaluate model robustness and uncertainty. RESULTS: Our analysis uses the information corresponding to 427 cases from the CAPS registry, the majority being women (68.8%), with a mean age of 45.7 years and bearing general mortality of 38.17% (female: 38.4%, male: 37.5%). Scheme 2 was the cost-effective strategy over scheme 1. The results were robust on discrete sensitivity analysis and probability sensitivity analysis (Monte Carlo simulation). CONCLUSION: To our knowledge, this is the first economic evaluation focused on the treatment of CAPS. For the Colombian health system, schemes 1 and 2 have similar behavior; nevertheless, scheme 2 represents the best cost-effectiveness ratio. This treatment approach is highly susceptible to the allocation of resources by the system and beneficial in terms of health outcomes.

Correlation and agreement between physical and ultrasound examination after a training session dedicated to the standardization of synovitis assessment in rheumatoid arthritis patients.

OBJECTIVES: Assessing disease activity in rheumatoid arthritis (RA) patients requires comprehensive quantification of tender and swollen joints. We aimed to evaluate the correlation and agreement between rheumatologists after a training session dedicated to the standardization of synovitis assessment and compare its performance with a reference imaging modality such as musculoskeletal ultrasonography (MSUS). METHODS: In this cross-sectional study, a total of 28 and 10 joints in RA patients were evaluated by physical examination and ultrasound (US), respectively. After participating in a training session, individual joint assessment for tenderness and swelling was performed by three rheumatologists. MSUS examination was performed separately by an experimented radiologist in a standardized manner, evaluating findings according to the Outcome Measures in Rheumatology Clinical Trial (OMERACT) guidelines. RESULTS: A total of 80 RA patients were included, with a mean Disease Activity Score based on 28 joints (DAS28)-ESR of 4.02. The interobserver overall agreement and concordance rate in a total of 2240 joints assessed was 81.7% (k = 0.449, p < 0.0001) for tender joints and 66% (k = 0.227, p < 0.0001) for swollen joints. The overall concordance rate was fair (Fleiss' kappa = 0.21, p = 0.027) with an overall agreement of 67.18% yet, more joints were found to be swollen by the US assessment, compared to the physical examination (43% vs 39%). CONCLUSION: In our study population, joint tenderness showed better interobserver agreement, correlation, and concordance rate than joint swelling. When comparing the US assessment to the physical examination, a fair overall concordance rate supports the need for the implementation of training sessions dedicated to standardization in rheumatology clinics.

Adenocarcinoma de colon sigmoide metastásico en paciente joven de presentación atípica: reporte de caso / An atypical presentation of metastatic sigmoid colon adenocarcinoma in a young patient: case report

El adenocarcinoma colorrectal es la tercera causa de muerte por cáncer en mujeres y la cuarta en hombres a nivel mundial. Se diagnostica en su mayoría en pacientes mayores a los 50 años, siendo la edad media al momento del diagnóstico los 72 años. A pesar eso, se estima que en los próximos años aumentará la incidencia en personas jóvenes y de mediana edad. Debido a esta proyección y considerando que la ausencia de signos y síntomas específicos no permite un diagnóstico oportuno, se hacen necesarias la sensibilización clínica y un alto índice de sospecha en las presentaciones atípicas. Se presenta el caso de una paciente joven que consulta por un cuadro de un mes de síntomas respiratorios quien, después de tratamiento antibiótico, antiviral e inmunomodulador sistémico, presenta sepsis de origen abdominal por peritonitis de cuatro cuadrantes secundaria a perforación de colon sigmoide debida a adenocarcinoma bien diferenciado, metastásico a pulmón, que la llevó a la muerte

Colorectal adenocarcinoma is the third leading cause of cancer death in women and the fourth in men worldwide. It is diagnosed mostly in patients older than 50 years, being 72 years the mean age at diagnosis. Despite this, it is estimated that the incidence in young and middle-aged people will increase in the coming years. Due to this projection and considering that the absence of specific signs and symptoms does not allow a timely diagnosis, clinical sensitization and a high index of suspicion are necessary in atypical presentations. We present the case of a young female patient who consulted for a one-month history of respiratory symptoms who, after treatment with antibio-tic, antiviral and systemic immunomodulatory agents, presented sepsis of abdominal origin due to four-quadrant peritonitis secondary to perforation of the sigmoid colon due to adenocarcinoma well differentiated, metastatic to the lung, which led to her death

Correlation and agreement between physical and ultrasound examination after a training session dedicated to the standardization of synovitis assessment in rheumatoid arthritis patients

Abstract Objectives: Assessing disease activity in rheumatoid arthritis (RA) patients requires comprehensive quantification of tender and swollen joints. We aimed to evaluate the correlation and agreement between rheumatologists after a training session dedicated to the standardization of synovitis assessment and compare its performance with a reference imaging modality such as musculoskeletal ultrasonography (MSUS). Methods: In this cross-sectional study, a total of 28 and 10 joints in RA patients were evaluated by physical examination and ultrasound (US), respectively. After participating in a training session, individual joint assessment for tenderness and swelling was performed by three rheumatologists. MSUS examination was performed separately by an experimented radiologist in a standardized manner, evaluating findings according to the Outcome Measures in Rheumatology Clinical Trial (OMERACT) guidelines. Results: A total of 80 RA patients were included, with a mean Disease Activity Score based on 28 joints (DAS28)-ESR of 4.02. The interobserver overall agreement and concordance rate in a total of 2240 joints assessed was 81.7% (k = 0.449, p < 0.0001) for tender joints and 66% (k = 0.227, p < 0.0001) for swollen joints. The overall concordance rate was fair (Fleiss' kappa = 0.21, p = 0.027) with an overall agreement of 67.18% yet, more joints were found to be swollen by the US assessment, compared to the physical examination (43% vs 39%). Conclusion: In our study population, joint tenderness showed better interobserver agreement, correlation, and concordance rate than joint swelling. When comparing the US assessment to the physical examination, a fair overall concordance rate supports the need for the implementation of training sessions dedicated to standardization in rheumatology clinics.

Treatment of systemic sclerosis-associated interstitial lung disease: A systematic literature review and meta-analysis / Tratamiento de la enfermedad pulmonar intersticial asociada con la esclerosis sistémica: revisión sistemática de la literatura y metaanálisis

ABSTRACT Background: Systemic sclerosis (SSc) is an immune-mediated disease characterized by small vessel vasculopathy and fibroblast dysfunction that leads to increased production of extracellular matrix. Interstitial lung disease represents one of the most common complications, by affecting almost 70% of patients with SSc. Objective: To evaluate the effectiveness of the pharmacological treatments available for systemic sclerosis-associated interstitial lung disease (SSc-ILD) based on pulmonary function tests and radiologic findings. Materials and methods: A systematic literature review and meta-analysis were conducted. A thorough literature search was made in EMBASE, PUBMED, and Cochrane CENTRAL to collect studies published between January 2015 and July 31 of 2019. The primary outcomes were forced vital capacity (FVC), diffusion capacity of carbon monoxide (DLCO), and high-resolution computed tomography findings (HR-CT). Studies using medications for the treatment of SSc-ILD including cyclophosphamide (CYC), mycophenolate mofetil (MMF), nintedanib, pirfenidone, or rituximab (RTX) were included. Effect measures were calculated based on available data, and a meta-analysis was made with these results. Results: We found a total of 312 studies. 49 studies were selected for full-text assessment after reading the abstracts. Finally, 14 studies were selected to be included in the final review. 2 meta-analyses, 8 clinical trials, 3 retrospective cohorts, and one nested case-control study were identified. The available evidence supports the use of CYC and MMF as the best options for the treatment of SSc-ILD, with MMF being the preferred option based on a better safety profile. Other medications such as RTX, pirfenidone, and nintedanib show potential as alternatives to CYC. The overall quality of evidence available is adequate based on generally well-designed studies. Meta-analysis was done by assessing >5% or >10% decrease of FVC when comparing pharmacological agents vs. placebo. Results show that the use of pharmacological agents is negatively associated with the worsening of FVC. However, high heterogeneity limits the number of studies used during quantitative analysis, affecting the overall results. Conclusions: Immunosuppressive therapies remain as the cornerstone of treatment of SSc-ILD, as most evidence show improvement or slow progression of pulmonary function tests by using them, especially CYC and MMF. However, more evidence is required regarding the use of alternative pharmacological agents, in search of an improvement in the quality of life of these patients.

RESUMEN Antecedentes: La esclerosis sistémica (ES) es una enfermedad mediada por el sistema inmunitario, caracterizada por vasculopatía de pequeños vasos y disfunción de los fibroblastos, que da lugar a una mayor producción de matriz extracelular. La enfermedad pulmonar intersticial representa una de las complicaciones más comunes, ya que afecta a cerca del 70% de los pacientes con ES. Objetivo: Evaluar la efectividad de los tratamientos farmacológicos disponibles para la enfermedad pulmonar intersticial asociada a la esclerosis sistémica (EPI-ES) basándonos en las pruebas de función pulmonar y los hallazgos radiológicos. Materiales y métodos: Se llevó a cabo una revisión sistemática de la literatura y un metaanálisis. Se hizo una búsqueda exhaustiva de literatura en EMBASE, MEDLINE PubMed y Cochrane (CENTRAL) con el fin de recopilar los estudios publicados entre enero de 2015 y el 31 de julio de 2019. Los resultados primarios fueron la capacidad vital forzada (CVF), la capacidad de difusión del monóxido de carbono (diffusing capacity of the lungs for carbon monoxide, DLCO), y los hallazgos de la tomografía computarizada de alta resolución (TCAR). Se incluyeron los estudios que utilizaron medicamentos para el tratamiento de la EPI-ES, incluyendo ciclofosfamida (CYC), micofenolato de mofetilo (MMF), nintedanib, pirfenidona o rituximab (RTX). Las medidas de efecto se calcularon con base en los datos disponibles, y se hizo un metaanálisis con estos resultados. Resultados: Encontramos un total de 312 estudios. Después de leer los resúmenes, se seleccionaron 49 estudios para la evaluación del texto completo. Finalmente, se seleccionaron 14 estudios para incluirlos en la revisión final. Se identificaron dos metaanálisis, ocho ensayos clínicos, tres cohortes retrospectivas y un estudio de casos y controles anidado. La evidencia disponible respalda el uso de CYC y MMF como las mejores opciones para el tratamiento de la EPI-ES, siendo el MMF la opción preferida basada en un mejor perfil de seguridad. Otros medicamentos como RTX, pirfenidona y nintedanib muestran potencial como alternativas a la CYC. La calidad global de la evidencia disponible es adecuada ya que parte de estudios por lo general bien diseñados. El metaanálisis se realizó evaluando una disminución > 5% o > 10% de la CVF al comparar los agentes farmacológicos vs. placebo. Los resultados muestran que el uso de agentes farmacológicos se asocia negativamente con el empeoramiento de la CVF. Sin embargo, la alta heterogeneidad limita el número de estudios utilizados durante el análisis cuantitativo, afectando los resultados generales. Conclusiones: Las terapias inmunosupresoras, especialmente la CYC y el MMF, siguen siendo la piedra angular del tratamiento de la EPI-ES, ya que la mayoría de la evidencia muestra una mejoría o una progresión lenta de las pruebas de función pulmonar al usarlas. Sin embargo, se requiere más evidencia con respecto al uso de agentes farmacológicos alternativos, en busca de una mejora de la calidad de vida de estos pacientes.