Developmental Disabilities

Developmental disability is a term used to describe life-long disabilities attributable to mental and/or physical or combination of mental and physical impairments, manifested prior to age twenty-two. The term is used most commonly in the United States to refer to disabilities affecting daily functioning in three or more of the following areas:

• capacity for independent living
• economic self-sufficiency
• learning
• mobility
• receptive and expressive language
• self-care
• self-direction

The term first appeared in U.S. law in 1970, when Congress used the term to describe the population of individuals who had historically been placed in state institutions, in its effort to improve conditions in these dehumanizing facilities (P.L. 91-517, “The Developmental Disabilities Services and Facilities Construction Act of 1970”). The law has since been amended many times, and now calls for the full community inclusion and self-determination of people with developmental disabilities (P.L. 106-402).

Frequently, people with mental retardation, cerebral palsy, autism spectrum disorder, various genetic and chromosomal disorders such as Down’s syndrome and Fragile X syndrome, and Fetal Alcohol Spectrum Disorder are described as having developmental disabilities. This use of the term is synonymous with the use of the term learning disability in the United Kingdom, and intellectual disability in Australia, Europe, Canada and elsewhere. Cognitive disability is also used synonymously in some jurisdictions.

Developmental disabilities are usually classified as severe, profound, moderate or mild, as assessed by the individual’s need for supports, which may be lifelong.
Causes of developmental disabilities

There are many social, environmental and physical causes of developmental disabilities, although for some a definitive cause may never be determined. Common factors causing developmental disabilities include:

• Brain injury or infection before, during or after birth
• Growth or nutrition problems
• Abnormalities of chromosomes and genes
• Babies born long before the expected birth date – also called extreme prematurity
• Poor diet and health care
• Drug misuse during pregnancy, including alcohol intake and smoking
• Child abuse can also have a severe effect on the development of a child, specifically the socio-emotional development
• Diagnosis of an autism spectrum disorder

Developmental disabilities affect between 1 and 2% of the population in most western countries, although many government sources acknowledge that statistics are flawed in this area. The worldwide proportion of people with developmental disabilities is believed to be approximately 1.4%. It is twice as common in males as in females, and some researchers have found that the prevalence of mild developmental disabilities is likely to be higher in areas of poverty and deprivation, and among people of certain ethnicities.

Associated issues

Physical health issues

There are many physical health factors associated with developmental disabilities. For some specific syndromes and diagnoses, these are inherent (such as poor heart function in people with Down’s syndrome); however lack of access to health services and lack of understanding by medical professionals is also a major contributing factor. People with severe communication difficulties find it difficult to articulate their health needs, and without adequate support and education might not recognize ill health. Epilepsy, sensory problems (such as poor vision and hearing), obesity and poor dental health are over-represented in this population. Life expectancy among people with developmental disabilities as a group is estimated at 20 years below average, although this is increasing with advancements in adaptive and medical technologies, and as people are leading healthier, more fulfilling lives, and some specific diagnoses (such as Freeman-Sheldon syndrome) do not impact on life expectancy.

Mental health issues (dual diagnoses)

Mental health issues, and psychiatric illnesses, are more likely to occur in people with developmental disabilities than in the general population. A number of factors are attributed to the high incidence rate of dual diagnoses:

• the high likelihood of encountering traumatic events throughout their lifetime (such as abandonment by loved ones, abuse, bullying and harassment)
• the social restrictions placed upon people with developmental disabilities (such as lack of education, poverty, limited employment opportunities, limited opportunities for fulfilling relationships, boredom)
• biological factors (such as brain injury, epilepsy, illicit and prescribed drug and alcohol misuse)
• developmental factors (such as lack of understanding of social norms and appropriate behavior, inability of those around to allow/ understand expressions of grief and other human emotions)

These problems are exacerbated by difficulties in diagnosis of mental health issues, and in appropriate treatment and medication, as for physical health issues.

Abuse and vulnerability

Abuse is a significant issue for people with developmental disabilities, and as a group they are regarded as vulnerable people in most jurisdictions. Common types of abuse include:

• Physical abuse (withholding food, hitting, punching, pushing, etc.)
• Neglect (withholding help when required, e.g., assistance with personal hygiene)
• Sexual abuse
• Psychological or emotional abuse (verbal abuse, shaming and belittling)
• Constraint and restrictive practices (turning off an electric wheelchair so a person cannot move)
• Financial abuse (charging unnecessary fees, holding onto pensions, wages, etc.)
• Legal or civil abuse (restricted access to services)
• Systemic abuse (denied access to an appropriate service due to perceived support needs)
• Passive neglect (a caregiver’s failure to provide adequate food, shelter)

Lack of education, lack of self-esteem and self-advocacy skills, lack of understanding of social norms and appropriate behavior and communication difficulties are strong contributing factors to the high incidence of abuse among this population.

In addition to abuse from people in positions of power, peer abuse is recognized as a significant, if misunderstood, problem. Rates of criminal offending among people with developmental disabilities are also disproportionately high, and it is widely acknowledged that criminal justice systems throughout the world are ill-equipped for the needs of people with developmental disabilities (as both perpetrators and victims of crime).

Challenging behavior

Some people with developmental disabilities exhibit challenging behavior, defined as “culturally abnormal behavior(s) of such intensity, frequency or duration that the physical safety of the person or others is placed in serious jeopardy, or behavior which is likely to seriously limit or deny access to the use of ordinary community facilities”. Common types of challenging behavior include self-injurious behavior (such as hitting, headbutting, biting), aggressive behavior (such as hitting others, screaming, spitting, kicking), inappropriate sexualized behavior (such as public masturbation or groping), behavior directed at property (such as throwing objects and stealing) and stereotyped behaviors (such as repetitive rocking, echolalia or elective incontinence).

Challenging behavior in people with developmental disabilities may be caused by a number of factors, including biological (pain, medication, the need for sensory stimulation), social (boredom, seeking social interaction, the need for an element of control, lack of knowledge of community norms, insensitivity of staff and services to the person’s wishes and needs), environmental (physical aspects such as noise and lighting, or gaining access to preferred objects or activities), psychological (feeling excluded, lonely, devalued, labelled, disempowered, living up to people’s negative expectations) or simply a means of communication. A lot of the time, challenging behavior is learned and brings rewards and it is very often possible to teach people new behavior to achieve the same aims.

Experience and research suggests that what professionals call ‘challenging behavior’ is often a reaction to the challenging environments that those providing services create around people with developmental disabilities. ‘Challenging behavior’ in this context is a method of communicating dissatisfaction with the failure of those providing services to focus on what kind of life makes most sense to the person, and is often the only recourse a developmentally disabled person has against unsatisfactory services or treatment and the lack of opportunities made available to the person. This is especially the case where the services deliver lifestyles and ways of working that are centered on what suits the service provider and it’s staff, rather than what best suits the person.

For more information about developmental disabilities go to: Developmental Disabilities