Assessing the Impact of Weighted Blankets on Anxiety for Patients With Eating Disorders in an Inpatient Setting: A Randomized Control Trial Pilot

Severe AN often results in medical instability and has one of the highest mortality rates of all psychiatric disorders (Watson & Bulik, 2013). The staggering 35% relapse rate among the AN population provides sufficient justification to examine other appropriate treatment disciplines, approaches and corresponding interventions. Further, there is a call to action to clearly establish the role of occupational therapy within the acute mental health setting (Lloyd & Williams, 2010).

Anxiety is a comorbidity for patients with AN. WB, an example of deep pressure stimulation, have been shown to reduce anxiety in adults and are a non-pharmaceutical intervention to manage anxiety (Chen et al., 2013; Mullen et al., 2008). However, not much is known regarding the effect of WB on patients with AN and ARFID. This RCT assesses the effect of WB on the anxiety of patients with severe AN and ARFID by answering the following research question: Is there a difference in anxiety reduction measured by the Beck Anxiety Inventory (BAI) between those who use WB and those who do not?

An RCT was implemented on the ACUTE Center for Eating Disorders at Denver Health Medical Center (ACUTE), a 24 bed medical stabilization unit for medically compromised eating-disordered patients. The occupational therapists (OT) identified eligible candidates during the initial evaluation. Patients over 18 who were clinically diagnosed with AN or ARFID upon admission (per DSM-V criteria) with a BAI score indicating moderate or high anxiety were considered eligible for the study. Informed consent was obtained by a member of the research team, and patients were randomly assigned to the intervention or control group. Patients in both groups were treated per unit protocol. In addition, participants in the intervention group were issued WB. Data was collected by OT and nursing staff per unit procedures.

The BAI, a 21-question self-report inventory measuring symptoms of clinical anxiety was the primary outcome measure. BAI was collected during OT evaluation and at discharge. Demographic variables such as gender, age, initial body mass index (BMI), initial percent ideal body weight and length of stay were collected. Descriptive statistics utilizing means, standard deviations, frequencies and percents were utilized as appropriate. A mixed effect linear regression model adjusting for treatment group and pre-post BAIs was conducted to assess the impact of WB on anxiety symptoms.

There were 24 patients enrolled in the study, with 12 assigned to the intervention group. One patient was excluded because of change in diagnosis after initial enrollment. Twenty-one patients were female (91%). The mean age of patients was 27 years old (SD: 10.6), initial BMI of 13.8 (kg/m²) (1.3) and average length of stay was 22.3 days (8.7). Over time, all patients regardless of treatment assignment had a statistically significant decrease on BAI by 7.9 points (p=0.04). Patients in the intervention group had a greater change in BAI by 1.2 points (p=0.89) compared to the control group (p=0.83). This is clinically significant, as participants in the intervention group had greater relief from at least one symptom commonly associated with anxiety compared to the control group.

This study provides support for the efficacy of a sensory intervention being favorably associated with decreased anxiety for patients with severe AN and ARFID in an inpatient setting. This study advances the field of occupational therapy by providing empirical evidence to support OTs working with patients who have major eating disorders; an emerging practice area. It also enhances the body of literature to support utilizing sensory interventions to promote wellness within a subset of the adult population.

References

Lloyd, C., & Lee, P. (2010) Occupational Therapy in the modern acute mental health setting: a review of current practice. International Journal of Therapy and Rehabilitation, 17(9), 436-442. doi:10.12968/ijtr.2010.17.9.78038

Watson, H. J., & Bulik, C. M. (2013). Update on the treatment of anorexia nervosa: review of clinical trials, practice guidelines and emerging interventions. Psychol Med, 43(12), 2477-2500. doi:10.1017/S0033291712002620

Chen, H.-Y., Yang, H., & Chi, H.-J. (2013). Physiological Effects of Deep Touch Pressure on Anxiety Alleviation: The Weighted Blanket Approach. Journal of Medical and Biological Engineering, 33(5), 463-470. doi:10.5405/jmbe.1043

Mullen, B., Champagne, T., Krishnamurty, S., Dickson, D., & Gao, R. X. (2008). Exploring the Safety and Therapeutic Effects of Deep Pressure Stimulation Using a Weighted Blanket. Occupational Therapy in Mental Health, 24(1), 65-89. doi:10.1300/J004v24n01_05