Physical Health, Mental Health, and Service Use in Youth with Developmental and Intellectual Disabilities: An Epidemiological Study

Purpose: Although research has documented that youth with developmental and intellectual disabilities experience poor physical and mental health outcomes, few studies have examined this population from an epidemiological perspective.  Of these limited studies, few have used national representative data. And, even fewer studies have described either prevalence of physical and mental health conditions or examined prevalence in service use.  Moreover, national representative studies rarely have examined disparities in demographics (e.g., race, SES); and, none have considered prevalence rates using Erikson’s developmental stages – early childhood, middle childhood, or adolescence.  Such descriptive, epidemiological research can provide a foundation for future analytical study.

The purpose of this study was to address the mentioned gaps in the literature by using national, parent-report data on youth with developmental and intellectual disabilities. We conducted a descriptive epidemiological study examining the prevalence of youth’s experience with physical and mental health conditions and service use. We also examined demographic characteristics, including developmental stages. We addressed the following research questions: (1) To what extent do youth with developmental and intellectual disabilities experience physical and mental health conditions? (2) What percentage of youth with developmental and intellectual disabilities participate in services?  (3) To what extent are disparities in demographic characteristics and developmental stages present in youth with developmental and intellectual disabilities?

Methods:  We used cross-sectional data collected in 2011/2012 from parents who completed the National Survey of Children with Special Healthcare Needs survey. Data represents a national representative sample of youth (0 to 17) in the United States. We restricted the sample to youth ages 3 to 17 with developmental and intellectual disabilities (N=1,015). The analyzed sample was 63% male.

OpenEpi was used to determine adequate sample size; we assumed a large population (1 million), 15% prevalence rate, 99.99% confidence level, and 1 design effect.  The necessary sample size was 772.  Because of a complex sampling design, Mplus 7.0 was used to obtain descriptive statistics and weighted percentages.

Results:  Thirty-five percent of the youth had one or more physical health condition, and 71% had one more mental health condition.   Ninety-five percent of youth received physical health service and 43% received mental health services.  With regards to race/ethnicity, 63%, 13%, 12%, and 12% of youth were identified as White, Black, Hispanic, and multiracial/other, respectively. As for developmental stages, 15%, 32%, and 53% of youth were in early childhood, middle childhood, and adolescence, respectively. 

The prevalence of physical health and physical health service use was constant across developmental stages.  The percentage of mental health concerns and mental health service varied across developmental stage. For example, percentage of mental health concerns in early childhood (57%) versus adolescence (75%).  Similarly, percentage of mental health service in early childhood (31%) versus adolescence (45%).

Conclusions and Implications:  This descriptive, epidemiological research provides a foundation for future research and has practice implications for youth with developmental and intellectual disabilities.  Clinicians should note the prevalence of physical and mental issues as well as prevalence of service use and consider these issues in treatment planning and implementation.