In another study, however, researchers found that although 57% of patients who suffered a fracture were vitamin-D deficient there was no significant association between vitamin D deficiency and fractures.20 Although there are no specific guidelines designed to evaluate and treat bone-health-related issues in adults with ID, it seems prudent to ensure adequate calcium and vitamin D intake, to encourage exercise if possible, and, in patients who suffer non-traumatic fractures, to evaluate for osteoporosis and give appropriate therapy according to the recommendations of the National Institutes of Health Consensus Development Panel on Osteoporosis Prevention, Diagnosis, and Therapy.21
Self-Injurious Behavior and the Risk of Polypharmacy
Adults with ID who are nonverbal may demonstrate self-injurious behavior (SIB) as a manifestation of pain from fracture, constipation, or other medical illnesses. The prevalence of SIB in this population ranges from 2% to 50%.22 Psychotropic medications are frequently used to protect patients from self-injury.23 The challenge for hospitalists is to keep patients from injuring themselves without masking underlying pathologic conditions.
Several hypotheses have tried to explain why patients engage in SIB: These include increased level of endogenous opioids leading to pain insensitivity, opioid release due to low endogenous opioid levels caused by the SIB itself, and reaction to pain. Breau and colleagues concluded that children with ID who suffered chronic pain self-injured less body surface area and fewer body sites than children without chronic pain. Patients without chronic pain who engaged in SIB were more likely to self-injure their heads and hands.22
If a medical etiology cannot be ascertained for aggressive, self-injurious, and destructive behavior, psychotropic agents are frequently employed, with rates that range from 18% to 49% in patients with ID.24 These medications should be prescribed in a start-low/go-slow manner and only after a thorough assessment has been performed and the physician has determined that the behavior cannot be redirected and poses an imminent risk to the patient.25
Because of ID patients’ decreased communication skills, polypharmacy is a significant risk; side effects of psychotropic agents may be mistakenly treated with additional agents. According to Janowsky and colleagues, the mean lowest effective dose of conventional antipsychotics such as haloperidol was 5.9 mg/day to maintain symptom suppression of maladaptive behavior, with relapse of symptoms occurring at a mean dose of 3.8 mg/day in an ID population.23 Atypical antipsychotics are now more widely used in adults with ID, and although they are less likely to cause extrapyramidal side effects, they can still lead to weight gain, sedation, increased lipid levels, and activation of diabetes mellitus. In one study, low dose risperidone (2 mg/day) reduced aberrant behavior by half in 57% of patients with ID. Increased appetite and weight gain were common side effects.26