Kids with disabilities and other special health care needs are at increased risk for bullying and generally show less motivation to succeed in school, new research indicates.

The findings come from a study published this week in the journal Pediatrics that looked at more than 1,450 students in fourth through sixth grade attending three rural school districts in Maryland and West Virginia.

Through surveys of the students and their parents, researchers found that about 1 in 3 kids in mainstream classrooms at the schools had some type of special health care need ranging from asthma and attention deficit hyperactivity disorder to emotional and behavioral disorders.

When the survey responses were matched up with school records, it became clear that children with disabilities missed more days of school and had lower grades, according to the research team from the University of Pennsylvania, Johns Hopkins and Marshall University.

These kids also reported higher levels of bullying and were less likely to feel safe in school, the study found.

Moreover, when it came to academics, students with special health care needs were less likely to report that getting good grades mattered to them.

“These problems threaten both their well-being as youth and their future flourishing as adults,” the study authors write. “Health and school professionals will need to work together to identify these children much earlier, ensure that they receive appropriate supports and services and monitor the effectiveness of services.”

Of the students surveyed, boys were twice as likely as girls to have special health care needs. Children from lower income households were also at increased risk for falling into this category, which could explain the high rate of the conditions among students in the study sample.