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Contexte: La forme grave de COVID-19 semble affecter de maniere disproportionnee les gens immunovulnerables, meme si les donnees canadiennes dans ce contexte sont limitees. Nous avons voulu determiner quels facteurs sont associes aux parametres de la forme grave de COVID-19 chez les receveurs de transplantations au Canada. Methodes: Nous avons procede a une etude de cohorte multicentrique prospective regroupant tous les receveurs d'une transplantation d'organe plein ayant requ un diagnostic de COVID-19 suivis dans 9 programmes de transplantation au Canada entre mars 2020 et novembre 2021. Les donnees ont ete analysees afin de degager les facteurs de risque a l'egard du recours a l'oxygenotherapie et autres criteres de la gravite de la maladie. Nous avons compare les parametres selon le type d'organe transplante et suivi devolution des parametres au fil du temps. Nous avons procede a une analyse multivariee pour determiner quelles variables sont associees au recours a l'oxygenotherapie. Resultats: En tout, 509 patients ayant requ une transplantation d'organe plein ont contracte la COVID-19 durant la periode de l'etude. Les facteurs de risque associes au recours a l'oxygenotherapie (n = 190) ou non (n = 319) incluaient l'age (age median 62,6 ans, intervalle interquartile [II] 52,5-69,5 ans c. age median 55,5 ans, II 47,5-66,5; p < 0,001) et le nombre de comorbidites (nombre median 3, II 2-3 c. nombre median 2, II 1-3; p < 0,001), de meme que les parametres concernant l'immunosuppression. Les receveurs d'une transplantation pulmonaire (n = 48) etaient plus susceptibles de souffrir d'une forme grave de la maladie, avec un taux de mortalite eleve (n = 15, 31,3%) comparativement aux receveurs d'autres organes, y compris le rein (n = 48, 14,8%), le creur (n = 1, 4,4%), le foie (n = 9, 11,4%) et le reinpancreas (n = 3, 12,0%) (p = 0,02). Les facteurs protecteurs contre le recours a l'oxygenotherapie incluaient le fait d'avoir subi une transplantation hepatique et de recevoir de l'azathioprine. Le fait d'avoir requ 2 doses de vaccin anti-SRAS-CoV-2 n'a pas eu d'influence appreciable sur le recours a l'oxygenotherapie. L'analyse multivariee a montre que l'age avance (rapport des cotes [RC] 1,04, intervalle de confiance [IC] de 95% 1,02-1,07) et le nombre de comorbidites (RC 1,63, IC de 95% 1,30-2,04), entre autres facteurs, etaient associes au recours a l'oxygenotherapie. La gravite de la maladie n'a pas considerablement diminue au fil du temps. Interpretation: Malgre les progres therapeutiques et la vaccination des receveurs d'une transplantation d'organe plein, les signes de gravite accrue de la COVID-19, en particulier chez les receveurs d'une transplantation pulmonaire, justifient le maintien des mesures de sante publique pour proteger ces personnes a risque, et l'utilisation hative de traitements contre la COVID-19 chez les receveurs d'une transplantation d'organe plein., Les receveurs d'une transplantation d'organe plein doivent prendre des immunosuppresseurs la vie durant pour prevenir le rejet. Au Canada, on estime a 3000 le nombre de transplantations effectuees annuellement, et [...]

Background: Severe COVID-19 appears to disproportionately affect people who are immunocompromised, although Canadian data in this context are limited. We sought to determine factors associated with severe COVID-19 outcomes among recipients of organ transplants across Canada. Methods: We performed a multicentre, prospective cohort study of all recipients of solid organ transplants from 9 transplant programs in Canada who received a diagnosis of COVID-19 from March 2020 to November 2021. Data were analyzed to determine risk factors for oxygen requirement and other metrics of disease severity. We compared outcomes by organ transplant type and examined changes in outcomes over time. We performed a multivariable analysis to determine variables associated with need for supplemental oxygen. Results: A total of 509 patients with solid organ transplants had confirmed COVID-19 during the study period. Risk factors associated with needing (n = 190), compared with not needing (n = 319), supplemental oxygen included age (median 62.6 yr, interquartile range [IQR] 52.5-69.5 yr v. median 55.5 yr, IQR 47.5-66.5; p < 0.001) and number of comorbidities (median 3, IQR 2-3 v. median 2, IQR 1-3; p < 0.001), as well as parameters associated with immunosuppression. Recipients of lung transplants (n = 48) were more likely to have severe disease with a high mortality rate (n = 15, 31.3%) compared with recipients of other organ transplants, including kidney (n = 48, 14.8%), heart (n = 1, 4.4%), liver (n = 9, 11.4%) and kidney-pancreas (n = 3, 12.0%) transplants (p = 0.02). Protective factors against needing supplemental oxygen included having had a liver transplant and receiving azathioprine. Having had 2 doses of SARS-CoV-2 vaccine did not have an appreciable influence on oxygen requirement. Multivariable analysis showed that older age (odds ratio [OR] 1.04, 95% confidence interval [CI] 1.02-1.07) and number of comorbidities (OR 1.63, 95% CI 1.30-2.04), among other factors, were associated with the need for supplemental oxygen. Over time, disease severity did not decline significantly. Interpretation: Despite therapeutic advances and vaccination of recipients of solid organ transplants, evidence of increased severity of COVID-19, in particular among those with lung transplants, supports ongoing public health measures to protect these at-risk people, and early use of COVID-19 therapies for recipients of solid organ transplants., Recipients of solid organ transplants take life-long immunosuppressive agents to prevent rejection. In Canada, an estimated 3000 transplant procedures are performed annually and 40 000 people are living with a [...]

The coronavirus disease 2019 pandemic has underscored the importance of vaccines, especially for immunocompromised populations like solid organ transplant recipients, who often have weaker immune responses. The purpose of this study was to compare deep learning architectures for predicting severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccine responses 12 months postvaccination in this high-risk group. Using data from 303 solid organ transplant recipients from a Canadian multicenter cohort, models were developed to forecast anti–receptor-binding domain antibody levels. The study compared traditional machine learning models—logistic regression, epsilon-support vector regression, random forest regressor, and gradient boosting regressor—and deep learning architectures, including long short-term memory (LSTM), recurrent neural networks, and a novel model, routed LSTM. This new model combines capsule networks with LSTM to reduce the need for large data sets. Demographic, clinical, and transplant-specific data, along with longitudinal antibody measurements, were incorporated into the models. The routed LSTM performed best, achieving a mean square error of 0.02 ± 0.02 and a Pearson correlation coefficient of 0.79 ± 0.24, outperforming all other models. Key factors influencing vaccine response included age, immunosuppression, breakthrough infection, body mass index, sex, and transplant type. These findings suggest that artificial intelligence could be a valuable tool in tailoring vaccine strategies, improving health outcomes for vulnerable transplant recipients.