Continued health challenges for individuals with intellectual disability observed as premature mortality

The risk for premature mortality in individuals with intellectual disability has generally decreased in modern welfare societies. Nevertheless, individuals with intellectual disabilities have continued health challenges associated with an increased risk of mortality, including young adults with mild intellectual disability. This was shown in a new study from Karolinska Institutet published in the journal JAMA Network Open.

Intellectual disability implies severe difficulties with abstract thinking, inference, problem solving, judgement and the ability to learn from experience. Intellectual disability affects many major life activities and people with intellectual disability need adjustment to their specific needs for optimal everyday functioning at school, in work life and other important areas of life. The severity of intellectual disability (from mild to profound) affects both the symptoms and the everyday functional impairments of the individual. Modern welfare societies strive for the inclusion of people with intellectual disabilities and enhanced possibilities for their active participation in important quotidian situations, including participation in their health and encounters with health care.

Agnieszka Butwicka Foto: Gunilla Sonnebring

- We know from international studies that mortality in individuals with ID has been decreasing during the past decades. However, we did not know much about the health challenges for individuals with mild ID who never lived in the large institutions that successively closed during the 70s – 80s, as noted by the last author of the study, Agnieszka Butwicka, MD and researcher at the Department for Medical Epidemiology and Biostatistics (MEB) at Karolinska Institutet.

According to the World Health Organization (WHO), analysing mortality is a valuable way of studying the effectiveness of a country’s health care system. Moreover, mortality studies can be used to study whether the health care system is equal between different groups, such as people with and without intellectual disability. The current study was a co-operation between Karolinska Institutet and Halmstad University in Sweden, and it used data from national health care and educational registers. The study included over 50.000 individuals with ID, and hundreds of thousand matched reference individuals from the general population.

Tatja Hirvikoski. Photo: Martin Hammar Foto: Martin Hammar

- Young adults with mild intellectual disability had an almost three times higher risk of dying during the follow-up time period, compared to their reference individuals from the general population. Many of the causes of death were potentially treatable, such as epilepsy, says the lead author of the study, Tatja Hirvikoski, who is associate professor at KIND (Center for Neurodevelopmental Disorders at Karolinska Institutet) and the Department of Women’s and Children’s Health at Karolinska Institutet.

The researcher conducted separate analyses including people with moderate to profound intellectual disability. Even in the group with more severe ID, epilepsy was an important risk factor. Moreover, it was common with diseases related to dysphagia—that is, difficulties with eating, drinking and swallowing—associated with food or fluids caught in one’s airways.

- It is important to identify symptoms and signs of ill-health as well as sub-optimal health care. Health care systems have to be accessible for everyone and adjustments for individual needs must be made for people with intellectual disabilities. Unfortunately, Sweden still lacks national clinical guidelines for people with ID at different severity levels, says Tatja Hirvikoski.


For more information contact:
Tatja Hirvikoski, associate professor, KIND (Center for Neurodevelopmental Disorders at Karolinska Institutet)
Institutionen för kvinnors och barns hälsa, Karolinska Institutet
Tel: 070-832 76 37 E-post:

Agnieszka Butwicka, MD/PhD MEB (Medicinsk epidemiologi och biostatistik), Karolinska Institutet

The study was funded by the Swedish Research Council for Health, Working Life andWelfare, the Swedish Research Council, Region Stockholm and Karolinska Institutet.

None of the authors reported any conflict of interest in relation to this study.



Association of Intellectual Disability With All-Cause and Cause-Specific Mortality in Sweden.
Hirvikoski T, Boman M, Tideman M, Lichtenstein P, Butwicka A
JAMA Netw Open 2021 Jun;4(6):e2113014