Non-suicidal self-injury among individuals with an eating disorder: A systematic review and prevalence meta-analysis

ObjectiveThis study aimed to quantify the prevalence of non-suicidal self-injury across eating disorders (EDs) and within diagnostic categories through systematic review and proportional, or so-called prevalence, meta-analysis.MethodIncluded studies had to contain individuals with a verified diagnosis of an ED. The last literature search was conducted on September 11, 2023, for studies published on or before September 2023 without a restriction on earliest publication year. Results were synthesized and analyzed using the "metaprop" package in R and presented using forest plots. Bias was assessed by a Peters' regression test and funnel plot.Results79 studies published between 1985 and 2023 were included encompassing 32,334 individuals with an ED. Importantly, 42 studies were not included in any other meta-analyses on self-injury in EDs to date. Overall prevalence of non-suicidal self-injury was 34.59% (95%CI = 30.49-38.81). Prevalence in anorexia nervosa restrictive type, binge/purge type, bulimia nervosa, binge eating disorder and other specified feeding/eating disorder were 23.19% (95%CI = 16.96-30.03%), 41.98% (95%CI = 32.35-51.91%), 36.97% (95%CI = 30.69-43.46%), 21.21% (95%CI = 14.93-28.12%) and 37.65% (95%CI = 28.59-47.09%), respectively. Prevalence estimations could not be estimated for other ED categories due to lack of a sufficient number of studies.DiscussionNon-suicidal self-injury is prevalent across both binge/purge and restrictive EDs. Considering the transdiagnostic nature of self-injurious behaviors in ED, the results highlight the importance of assessment and monitoring of self-injury in people with ED, irrespective of specific diagnoses. The method of determining self-injury varied across studies and may limit this study.Public SignificanceThis study highlights the prevalence of self-injury across eating disorders irrespective of diagnosis and within specific EDs. While diagnoses known to exhibit self-injurious behaviors (e.g., bulimia nervosa, anorexia nervosa binge/purge subtype) demonstrated the highest prevalence of self-injury, all diagnoses were found to have a prevalence greater than 20%. These findings suggest the importance of assessing and monitoring all individuals with an eating disorder for the presence of self-injury. ObjetivoResultadosEste estudio tuvo como objetivo cuantificar la prevalencia de la autolesion no suicida en los trastornos de la conducta alimentaria (TCA) y dentro de las categorias diagnosticas mediante una revision sistematica y un metaanalisis proporcional, tambien llamado metaanalisis de prevalencia.MetodoLos estudios incluidos debian contener individuos con un diagnostico verificado de un TCA. La ultima busqueda bibliografica se realizo el 11 de septiembre de 2023, para estudios publicados en o antes de septiembre de 2023 sin restriccion en el ano de publicacion mas temprano. Los resultados fueron sintetizados y analizados utilizando el paquete "metaprop" en R y presentados mediante graficos de bosque. El sesgo se evaluo mediante una prueba de regresion de Peters y un grafico de embudo.Se incluyeron 79 estudios publicados entre 1985 y 2023 que abarcaron a 32,334 individuos que padecian un TCA. Es importante destacar que 42 estudios no se incluyeron en ningun otro metaanalisis sobre autolesion en TCA hasta la fecha. La prevalencia general de la autolesion no suicida fue del 34.59% (IC del 95% = 30.49-38.81). La prevalencia en la anorexia nerviosa subtipo restrictivo, subtipo atracones/purga, bulimia nerviosa, trastorno de atracones y otros trastornos especificados de la conducta alimentaria y de la alimentacion fue del 23.19% (IC del 95% = 16.96-30.03%), 41.98% (IC del 95% = 32.35-51.91%), 36.97% (IC del 95% = 30.69-43.46%), 21.21% (IC del 95% = 14.93-28.12%) y 37.65% (IC del 95% = 28.59-47.09%), respectivamente. No se pudieron estimar las estimaciones de prevalencia para otras categorias de TCA debido a la falta de un numero suficiente de estudios.DiscusionLa autolesion no suicida es prevalente tanto en los TCA subtipo de atracon/purgacion como en los restrictivos. Dada la naturaleza transdiagnostica de los comportamientos autolesivos en los TCA, los resultados resaltan la importancia de la evaluacion y el monitoreo de la autolesion en personas que padecen TCA, independientemente de los diagnosticos especificos. El metodo para determinar la autolesion vario entre los estudios y puede limitar este estudio.