Weight management in adults with intellectual and developmental disabilities: A randomized controlled trial of two dietary approaches.

BACKGROUND: The prevalence of obesity among individuals with intellectual and developmental disabilities (IDD) is equal to or greater than the general population. METHODS: Overweight/obese adults (BMI ≥25 kg/m2 ) with mild-to-moderate intellectual and developmental disabilities were randomized to an enhanced stop light diet (eSLD = SLD + portion-controlled meals, n = 78) or a conventional diet (CD, n = 72) for an 18 months trial (6 months weight loss, 12 months maintenance). Participants were asked to increase physical activity (150 min/week), self-monitor diet and physical activity and attend counselling/educational sessions during monthly home visits. RESULTS: Weight loss (6 months) was significantly greater in the eSLD (-7.0% ± 5.0%) compared with the CD group (-3.8% ± 5.1%, p < .001). However, at 18 months, weight loss between groups did not differ significantly (eSLD = -6.7% ± 8.3%; CD = 6.4% ± 8.6%; p = .82). CONCLUSION: The eSLD and CD provided clinically meaningful weight loss over 18 months in adults with intellectual and developmental disabilities.

Discovering indices of contingency awareness in adults with multiple profound disabilities.

We conducted two studies to examine parameters of social attention in contingency awareness training using switch activation with individuals who had multiple profound disabilities. In Study 1 we compared leisure devices and social attention as reinforcing stimuli with 5 individuals. Results indicated the reinforcing qualities of social attention over leisure devices with 2 individuals and documented the importance of session length in training. In Study 2 we investigated idiosyncratic behaviors as indicators of responsiveness with 3 of the 5 original participants as they activated switches. Behavior changes during switch activation versus nonactivation times in the leisure device and social attention conditions suggested volitional movement supporting contingency awareness and preference. Implications for clinical practice are discussed.

A novel method for testing learning and preferences in people with minimal motor movement.

Ten individuals with profound multiple impairments were given novel tests for learning and preference with adaptive switches and leisure-oriented devices, such as audio tape players. Typically, tests for learning include a baseline or extinction component in which the adaptive switch and device are not connected as a control for incidental or involuntary switch use. As an alternative, conditions were compared in sets of six sessions each in which switch closure caused (a) Activation of a device, (b) Deactivation of an already operating device, and (c) Deactivation of one of two devices and Activation of the other (Two-Choice). Changes in behavior indicative of learning were observed in eight participants in Activation-Deactivation conditions. The Two-Choice Condition produced indices of learning that also showed a preference for one device over the other with five participants. The preferences observed in the Two-Choice Condition had not been seen in the Activation or Deactivation Condition data. People with profound multiple impairments evinced leisure-device preferences, but such preferences may not lead to differential responding across opportunities with only one device at a time.

Interaction of reinforcement schedules, a behavioral prosthesis, and work-related behavior in adults with mental retardation.

The effects of variable-interval (VI) and fixed-ratio (FR) schedules of reinforcement for work-related behavior and an organizer for the work materials (behavioral prosthesis) were evaluated with 3 adults with severe or profound mental retardation. The participants had been recommended for study because of high rates of off-task and aberrant behavior in their daily vocational training programs. For 2 participants, VI and FR schedules resulted in the same outcome: more aberrant behavior than on-task and off-task behavior combined. The FR schedule nearly eliminated emission of aberrant and off-task behavior by the 3rd participant. Combining the behavioral prosthesis with FR reinforcement (FR+O) increased the proportion of time spent in on-task behavior by all participants under certain FR schedule parameters. Second-by-second analyses of the observation records revealed that FR schedules reduced off-task and aberrant behavior during work sequences (i.e., ratio runs), and FR+O led to a further reduction of these behaviors during postreinforcement pauses. Overall, the results show how organizer and schedule parameters can be adjusted to produce an optimized balance between productivity and reinforcement while undesirable behavior is minimized.

A comparison of two weight management programs for adults with mobility impairments.

BACKGROUND: Individuals with physical disabilities experience disparities in obesity; yet few interventions have incorporated accommodations necessary for weight loss in this population. OBJECTIVE/HYPOTHESIS: This project compared the effectiveness of two weight loss interventions among individuals with physical disabilities. METHODS: Adults with physical disabilities who were overweight or obese were randomized across two diet approaches: a modified version of the MyPlate diet (usual care (UC)) and a modified Stoplight Diet (SLDm) supplemented with portion-controlled meals. Project staff met monthly with each participant to measure weight, 24-recalls of diet intake, self-tracking of foods and beverages, and physical activity during the preceding month. RESULTS: Of 126 enrollees, 70% completed the initial 6-month diet phase and 60% of these completed a 6-month follow-up phase. Participants in the SLDm group reduced weight and BMI during the 6 month intervention, and maintained or lost more weight during the 6 month maintenance period. Alternately, the UC diet resulted in a reduction in weight and BMI only at 6 months. BMI from baseline was significantly more improved for SLDm than UC and, among those who lost weight, the SLDm group lost more weight at 6 and 12 months. CONCLUSIONS: These results demonstrate that interventions with proper design and accommodations can overcome the barriers to weight loss unique to individuals with mobility impairments with low income. Additionally, the results suggest that using portion control may be more effective than teaching portion sizes.

Effects of ambient stimuli on measures of behavioral state and microswitch use in adults with profound multiple impairments.

The effects of different types and amounts of environmental stimuli (visual and auditory) on microswitch use and behavioral states of three individuals with profound multiple impairments were examined. The individual's switch use and behavioral states were measured under three setting conditions: natural stimuli (typical visual and auditory stimuli in a recreational situation), reduced visual stimuli, and reduced visual and auditory stimuli. Results demonstrated differential switch use in all participants with the varying environmental setting conditions. No consistent effects were observed in behavioral state related to environmental condition. Predominant behavioral state scores and switch use did not systematically covary with any participant. Results suggest the importance of considering environmental stimuli in relationship to switch use when working with individuals with profound multiple impairments.

Evidence of contingency awareness in people with profound multiple impairments: response duration versus response rate indicators.

Evidence of contingency awareness in people with profound multiple impairments is often elusive due to numerous variables that impede learning and contribute to performance variability. Recent research has shown that measuring duration of responding rather than rate has promise for more accurate inferences. Duration measures of adaptive-switch use were obtained with 50 participants during empirical tests for contingency awareness. Nearly 80% had test performance patterns indicative of cause-and-effect learning or contingency awareness. Rate data were obtained concurrent with duration measures for 33/50 participants. Although statistical analysis indicated an interaction of test condition and rate of responding, the performance pattern indicative of contingency awareness was observed in only about 50% of the sets of rate data. Further, rate-based indications of contingency awareness were not consistently confirmed by the duration data. The results strongly support inclusion of response duration measures in evaluation of adaptive-switch use and contingency awareness.

Establishing a conditional signal for assistance in teenagers with blindness.

Five teenagers with severe intellectual impairments and no discernible communication skills were enrolled in training to teach a conditional request for assistance using a speech-generating device (SGD). All were either blind or severely visually impaired since birth. All learned to operate an adaptive switch to control sensory outcomes, next showed preferences among sensory outcomes, and then demonstrated the ability to use their switch to signal for assistance with an SGD when the sensory outcome was remotely disabled. During the signaling phase, or subsequent attempts to generalize its use outside the laboratory, three participants began vocalizing. Most notably, they began imitation of the word "song" or the word "help" emitted by the SGD. The potential role of cause-and-effect training with adaptive switches is discussed.

Teaching Individuals to Signal for Assistance in a Timely Manner.

The study describes the adaptive-switch performances of 8 adults with severe multiple impairments. Each was given a series of progressively more difficult discrimination tasks that, if solved, would require the participant to close the switch to activate a device that was not operating or to stay away from the switch if the device was operating. Then in a 2-choice format, a preference test was conducted by providing 2 devices simultaneously that could be activated or deactivated by closure or release of the switch. Finally, a preferred device was activated and then surreptitiously deactivated. Switch closures in this contingency activated a speech-generating device that played the message, "Help me." All 8 participants learned to control devices using their adaptive switch, but only 4 participants learned to make a request for help. Reasons for the different performances across learners and nonlearners are discussed.

Innovation of a reinforcer preference assessment with the difficult to test.

In this study, we continued evaluation of a two-choice preference assessment aimed at identifying a hierarchy of reinforcers for individuals with only one voluntary motor sequence-closing and releasing an adaptive switch. We assessed preferences among types of sensory stimulation in 6 adults with multiple profound impairments using concurrent synchronous reinforcement contingencies. Pre-experimental assessments with various types of stimulation led to the selection of music (A), vibration (B), and either olfactory or visual stimulation (C) as the 3 modalities for continued testing. Each participant received opportunities for familiarization with each type of stimulation in blocks of six 20-min sessions in which the closure of an adaptive switch produced the stimulation for as long as the switch remained closed. Next, participants could choose between pairs of types of stimulation in blocks of 12 sessions. In the first 6 of the 12 sessions, switch closure activated one type (e.g., A) and switch release activated the contrasted type (e.g., B). In the second 6 sessions, the contingencies were reversed. Two additional 12-session blocks completed all possible contrasts (AB, BC and AC). Four of the 6 participants showed distinct preferences in these two-choice tests with indications of preference hierarchies. The results demonstrate a method for obtaining indications of relative preference for potentially reinforcing stimuli from individuals without communication and without the abilities to act on more than one switch.

Adapted Digital Music Players for Individuals with Severe Impairments.

Portable music production devices, such as radios, cassette players and MP3 players have characteristics that make them less than ideal for teaching the cause-and-effect relationships that would enable children and adults with severe impairments to control them independently and appropriately. Even when adapted for control with adaptive switches, the relationship between switch closure and on-off operation results in contingency characteristics that can inhibit learning. Some solutions to these problems are described, and for those individuals who can learn with complex contingencies, some promising products are reviewed.

Evaluation of an approach to weight loss in adults with intellectual or developmental disabilities.

Of 79 overweight adults with intellectual or developmental disabilities who participated in a weight loss intervention, 73 completed the 6-month diet phase. The emphasis in the intervention was consumption of high volume, low calorie foods and beverages, including meal-replacement shakes. Lower calorie frozen entrees were recommended to control portion size. A walking activity was encouraged. Participants attended monthly meetings in which a small amount of cash was exchanged for self-recorded intake and exercise records completed on picture-based forms. Average weight loss was 13.2 pounds (6.3%) of baseline weight at 6 months, with weight loss shown by 64 of the 73 individuals enrolled. Those completing a 6-month follow-up phase showed weight loss of 9.4% of baseline. Increased choice and control are discussed as possible contributors to individual success.