Tuesday 13 August 2013

Research Tuesday - Pica

The Article
Pica in persons with developmental disabilities: Approaches to treatment.
Johnny L. Matson, Megan A. Hattier, Brian Belva, Michael L. Matson
Research in Developmental Disabilities 34 (2013) 2564 - 2571.

Why did I choose this article?
Since pica is usually described as a challenging behaviour you might be wondering why a SLP might be interested in the topic enough to blog about it. Basically the links between communication and behaviour and eating and drinking are all quite close and many SLPs working in the disability sector will probably encounter the challenging behaviour of pica at some point in their careers. This might be because no one has identified it as a problem before or people think that because the person is eating, a referral to the SLP is the best option. The treatments described in this article are very much the domain of the psychologist, so if you're supporting someone with pica, hopefully you will be able to work collaboratively with a psychologist.
During my career I have supported people who were interested in chewing, eating or just storing non-food items in their mouths. Items included sticks, rocks, leaves, plastic, cloth, pencils, paper, hair and metal. I've also met people with complications from 'gastric bezoar' which is a collection of material in the gastrointestinal tract: http://www.uptodate.com/contents/gastric-bezoars

What is pica?
Pica is defined by the authors as repetitively ingesting (eating) items with no nutritional value (eg. paint, hair, dirt, cigarette butts etc). They report that the DSM IV definition states that pica is the persistent eating of non-nutritive items for at least 1 month and the behaviour must be developmentally inappropriate and not be part of a culturally sanctioned practice (American Psychiatric Association, 2000). 
I'm unaware if this definition has changed in DSM V. http://www.dsm5.org/Pages/Default.aspx
Pica can have serious implications for a person's health and wellbeing.

What types treatments currently exist?
Positive procedures:
- Environmental enrichment
- Reinforcement
- Biological interventions
   - Pharmacotherapy
   - Nutritional supplements

These authors provide quite descriptive analysis off all the published treatment approaches. This can be complicated because most interventions have multiple components.

Punishment procedures:
- Aversive stimuli
- Work and effort procedures
   - Overcorrection
- Restraint
   - Mechanical restraint
   - Physical restraint
- Time out
- Response blocking/interruption

Punishment procedures have faded from clinical use over time. Studies showing the efficacy of these procedures were mostly published during the 70's and 80's. 

The Bottom Line
ABA (Applied Behaviour Analysis) approaches provide by far the most compelling research evidence to date. This has been recognised in the literature for some time now. This article reported on >30 studies using ABA to treat pica. 
The authors add "It makes sense to start with the least intrusive methods first including functional assessment and reinforcement."

Some More Thoughts...
This article is not a "How to..." for helping people who have pica. It doesn't provide in depth information on the quality of studies. If you don't know much about ABA you'll need some additional reading to work in this area. After reading this I find myself wanting/needing more information to help me add this knowledge to my practice.
Also, the quality of the studies in this area is unclear. The authors refer occasionally to case series and some single case experimental designs, but it is difficult to glean the overall quality of studies in this area.

Now, off you pop! Read it yourself and let me know your thoughts.

No comments:

Post a Comment