Mortality in adults with moderate to profound intellectual disability: a population-based study

Area of Science:

• Public Health
• Epidemiology
• Disability Studies

Background:

• People with intellectual disability (ID) face significant health inequalities, including elevated mortality rates compared to the general population.
• This study is the first UK population-based investigation into excess mortality among individuals with ID.

Purpose of the Study:

• To quantify the extent of excess all-cause and disease-specific mortality in adults with moderate to profound ID.
• To identify variations in mortality risk within the ID population based on age, sex, Down syndrome status, and geographic location.

Main Methods:

• Indirect standardization was used to calculate Standardized Mortality Ratios (SMRs) for adults (20+ years) with moderate to profound ID.
• Data were collected from Leicestershire and Rutland, UK, between 1993-2005, comparing the ID population to the general population.
• SMRs were analyzed by age, sex, Down syndrome presence, and urban/rural residence.

Main Results:

• The study identified 2436 adults with ID, with 17% dying during follow-up.
• All-cause and disease-specific mortality were approximately threefold higher in the ID population compared to the general population.
• Young adults experienced the most significant excess mortality, with SMRs nearly nine times higher for men and over 17 times higher for women in their twenties. Individuals with Down syndrome and women in urban areas faced particular disadvantage.

Conclusions:

• Younger individuals, women, those with Down syndrome, and those residing in urban areas showed disproportionately high mortality rates.
• These findings highlight critical health disparities requiring further investigation into underlying causes, potentially including socio-economic factors.