Análise de sobrevivência aplicada à avaliação do tratamento da esporotricose por Sporothrix brasiliensis em gatos domésticos

Abstract

Survival analysis can be described as a statistical technique applied when the object of study is the time until the occurrence of the event or the risk of occurrence of this event in time. The main characteristic of this type of study is the presence of censored data, which are partial observations of some individuals. Despite frequent data of this nature in animal health studies, few applied survival analyses. This study aimed to assess the probabilities of death and cure for domestic cats in sporotrichosis treatment using survival analysis and also verify the influence of sex and the presence of respiratory signs on the probabilities of cure and death. Sporotrichosis is a serious fungal zoonosis and stands out today as one of the main infectious causes of suffering and death in domestic cats in urban environments. Data from 35 adult cats followed up on treatment of sporotrichosis with itraconazole monotherapy at a dose of 100mg per day were used. The characteristics of these patients were analyzed using the survival analysis technique in a classic way: first using the non-parametric approach with the Kaplan-Meier Estimator and then applying parametric approaches using the Weibull model for the probability of death and lognormal model for the cure probability, as they showed better adherence to the data compared to the other models. The maximum risk of death among treated cats was 77%. The probability of cure for cats in the first two months of treatment is greater than 80%. The sex of the animal did not influence the cure or death rates and the presence of respiratory signs was associated with the cure of the animals, but studies with a more robust sample size are needed to estimate the influence of this factor on the probabilities of cure over time.