Patients with autism had a fivefold increase in adjusted relative risk of self-harm.
Young patients with autism are similarly at risk of self-harm as patients with depression or attention deficit/hyperactivity disorder (ADHD).
A team, led by Isidora Stark, Karolinska Institutet, Sweden, Department of Global Public Health, investigated whether autism is a risk factor for self-harm independently of psychiatric comorbidities and how it differs from self-harm in non-autistic individuals.
Younger patients with autism can often engage in self-harm and are often at risk of premature death by suicide.
In the study, the investigators used data from The Stockholm Youth Cohort, a total-population register study that included all residents in Stockholm County aged 0-17 years between 2001-2011.
Each participant was followed from age 10-27 years for hospital admissions because of self-harm and the investigators used modified Poisson regression to calculate relative risks using robust standard error to derive 95% confidence intervals.
The analysis included 410,372 participants, 9070 of which had a diagnosis of autism. The investigators found patients with autism had a fivefold increase in adjusted relative risk of self-harm (RR, 5.0; 95% CI, 4.4-5.6). This risk increase was more pronounced for autism without intellectual disability. It was also particularly high for self-cutting (RR, 10.2; 95% CI, 7.1-14.7) and more violent methods (RR, 8.9; 95% CI, 5.2-15.4).
Autism and self-harm was also deemed to have independent, but clearly exacerbated by comorbid psychiatric conditions. There was a similar magnitude of risks linked to these conditions that was not explained by shared familial factors.
“Self-harm severe enough to present to medical services is as common in autistic youth as in those with depression or ADHD,” the authors wrote. “Potentially more lethal methods are more likely to be used of autistic self-harmers.”
Earlier this year, investigators found clear different in gut bacteria between pediatric patients with autism spectrum disorder (ASD) and pediatric patients without ASD.
While it is known that ASD is linked to altered gut microbiota, there is little research into the altered bacterial species. The majority of studies in this space have been plagued by small sample sizes. The overall etiology of ASD is also unclear.
Patients with ASD had significantly higher relative abundance of Enterobacteriaceae (FDR-P <0.001) at the family level, but a significant reduction of the taxa Monoglobaceae (FDR-P = 0.009).
There were also 12 taxa peculiar in the ASD group, including Hungateiclostridiaceae, Caldicoprobacteraceae, and norank_o__norank_c__Clostridia belonging to the class Clostridia.
For the genera level, Bifidobacterium, Bacteroides, Blautia, Faecalibacterium, and Anaerostipes made up the main part of the gut microbiota in both groups.
However, after correcting for multiple comparisons, the relative abundances at the phylum level of Actinobacteria and Proteobacteria in the study group was significantly higher than those in the control group.
There was also a relative abundance of the Escherichia-Shigella genus in the case group that was significantly higher than the control group. In addition Blautia and unclassified_f__Lachnospiraceae was actually higher in the control group.
The study, “Sublingual Immunotherapy Improves Severity of Atopic Dermatitis,” was published in Acta Psychiatrica Scandinavica.