Pica in persons with developmental disabilities: Approaches to treatment

Highlights

• Applied behavior analysis (ABA) is the treatment approach for pica with the best research support.

• The trend is toward functional assessment and reinforcement schedules and away from noxious stimuli.

• There is a need for more research on pica.

Abstract

Pica is a very serious problem in which an individual ingests substances without nutrition value, such as paper and paint. As this behavior is often life-threatening resulting in surgery, pica has received attention from researchers for several decades. During that time, a number of interventions have been devised, such as behavioral methods (e.g., aversive stimuli, overcorrection, time-out, reinforcement) and biological interventions (e.g., pharmacotherapy, nutritional supplements). This paper is a broad review of the research on treatment studies for this problem, with a focus on persons with autism and/or intellectual disability (ID), which constitutes almost all of the published treatment papers. In addition, strengths and weaknesses of different pica treatments are discussed. Upon review, applied behavior analysis (ABA) was found to have the most robust empirical support to treat this behavior. Most clinicians are drifting away from aversive techniques and relying on more positive procedures to guide their treatment plans. The implications of current status and future directions for research are also addressed.

Introduction

Developmental disabilities constitute a broad range of disorders, with perhaps the two most prominent of these being intellectual disability (ID) and autism, both of which overlap to a large extent (Dawson et al., 1998, Matson et al., 2009b, Matson et al., 1996, Matson et al., 2009d). Problems that are evident in these persons are generally of three types: skill deficits, challenging behaviors (CBs), and psychopathology. Typical skill deficits involve communication, social skills, and adaptive behaviors (Fodstad et al., 2010b, Fodstad et al., 2009, Lancioni et al., 2010, Matson et al., 2009a, Matson et al., 1996, Matson et al., 2010b, Matson et al., 2010c, Matson et al., 2007, Petry et al., 2010, Smith and Matson, 2010, Sturmey et al., 2010). Among the CBs common in persons with developmental disabilities are stereotypies, aggression, self-injury, property destruction, and pica (Embregts et al., 2010, Kuhn and Matson, 2004, Matson et al., 1997a, Matson et al., 1997b, Matsuura et al., 2010, Murphy et al., 2010, Paclawskyj et al., 1997, Poppes et al., 2010, Rose, 2010, Strachan et al., 2010).

For obvious reasons, a range of interventions have been used to treat CBs. Psychotropic medications have been frequently used, but their effectiveness is open to question (Singh et al., 2010). Additionally, they are often used long term with serious, irreversible side effects occurring (Advocate et al., 2000, Fodstad et al., 2010a, Mahan et al., 2010, Matson et al., 2006, Matson et al., 2010a, Matson and Mahan, 2010). More research has accumulated on the effectiveness of ABA than other treatment methods for CBs in general, and the side effects are less serious (Matson and Boisjoli, 2009, Matson and Keyes, 1988, Matson and Keyes, 1990, Matson and LoVullo, 2008, Matson and LoVullo, 2009, Matson et al., 2009c, Matson et al., 2009e, Matson and Taras, 1989, Taras et al., 1988).

One of the most serious of these CBs is pica. Pica is defined as repetitively ingesting items with no nutritional value (e.g., paint, hair, dirt, cigarette butts; Bell and Stein, 1992, Bugle and Rubin, 1993, Carter et al., 2004, Pace and Toyer, 2000, Swift et al., 1999, Tewari et al., 1995). According to the Diagnostic and Statistical Manual of Mental Disorder, Fourth Edition-Text Revision (DSM-IV-TR), the current diagnostic criteria state that pica is the persistent eating of nonnutritive items for at least 1 month, the behavior must be developmentally inappropriate, and the behavior must not be part of a culturally sanctioned practice (American Psychiatric Association, 2000). Prevalence rates have been found to range anywhere from 4% to approximately 26% (Ali, 2001, Ashworth et al., 2009, Danford, 1982, Hardon and Sahl, 1997, Swift et al., 1999). Pica often results in very serious effects including surgery and a high mortality rate (Bell & Stein, 1992). Thus, it should be a very high priority for treatment research. Having said this, the studies in this area have been very sporadic. Additionally, self-injury and aggression have been topics that have received considerably more attention.

The purpose of this paper was to provide a review of research on the development of interventions for pica. Efforts are also made to identify strengths and weaknesses in the current literature and to emphasize various areas for further study. Most importantly, we hope to highlight the importance of more attention and research, to what is certainly one of the most critical topics in the field of developmental disabilities. All studies referenced in this general review of pica treatments were acquired by a search for pica treatments at www.scopus.com.