IMPORTANCE Cognitive behavioral therapy for insomnia (CBT-I) is the most prominent nonpharmacologic treatment for insomnia disorders. Although meta-analyses have examined primary insomnia, less is known about the comparative efficacy of CBT-I on comorbid insomnia.OBJECTIVE To examine the efficacy of CBT-I for insomnia comorbid with psychiatric and/or medical conditions for ( 1) remission from insomnia; (2) self-reported sleep efficiency, sleep onset latency, wake after sleep onset, total sleep time, and subjective sleep quality; and (3) comorbid symptoms. DATA SOURCES A systematic search was conducted on June 2, 2014, through PubMed, PsycINFO, the Cochrane Library, and manual searches. Search terms included (1) CBT-I or CBT or cognitive behavioral [and its variations] or behavioral therapy [and its variations] or behavioral sleep medicine or stimulus control or sleep restriction or relaxation therapy or relaxation training or progressive muscle relaxation or paradoxical intention; and (2) insomnia or sleep disturbance.STUDY SELECTION Studies were included if they were randomized clinical trials with at least one CBT-I arm and had an adult population meeting diagnostic criteria for insomnia as well as a concomitant condition. Inclusion in final analyses (37 studies) was based on consensus between 3 authors' independent screenings. DATA EXTRACTION AND SYNTHESIS Data were independently extracted by 2 authors and pooled using a random-effects model. Study quality was independently evaluated by 2 authors using the Cochrane risk of bias assessment tool. MAIN OUTCOMES AND MEASURESA priori main outcomes (ie, clinical sleep and comorbid outcomes) were derived from sleep diary and other self-report measures.RESULTS At posttreatment evaluation, 36.0% of patients who received CBT-I were in remission from insomnia compared with 16.9% of those in control or comparison conditions (pooled odds ratio, 3.28; 95% CI, 2.30-4.68; P < .001). Pretreatment and posttreatment controlled effect sizes were medium to large for most sleep parameters (sleep efficiency: Hedges g = 0.91 [95% CI, 0.74 to 1.08]; sleep onset latency: Hedges g = 0.80 [95% CI, 0.60 to 1.00]; wake after sleep onset: Hedges g = 0.68; sleep quality: Hedges g = 0.84; all P < .001), except total sleep time. Comorbid outcomes yielded a small effect size (Hedges g = 0.39 [95% CI, 0.60-0.98]; P < .001); improvements were greater in psychiatric than in medical populations (Hedges g = 0.20 [95% CI, 0.09-0.30]; χ 2 test for interaction = 12.30; P < .001). CONCLUSIONS AND RELEVANCECognitive behavioral therapy for insomnia is efficacious for improving insomnia symptoms and sleep parameters for patients with comorbid insomnia. A small to medium positive effect was found across comorbid outcomes, with larger effects on psychiatric conditions compared with medical conditions. Large-scale studies with more rigorous designs to reduce detection and performance bias are needed to improve the quality of the evidence.

Objective Cognitive deficits are common in Parkinson’s disease (PD) and exacerbate the functional limitations imposed by PD’s hallmark motor symptoms, including impairments in walking. Though much research has addressed the effect of dual cognitive-locomotor tasks on walking, less is known about their effect on cognition. The purpose of this study was to investigate the relation between gait and executive function, with the hypothesis that dual tasking would exacerbate cognitive vulnerabilities in PD as well as being associated with gait disturbances. Method Nineteen individuals with mild-moderate PD without dementia and 13 age- and education-matched normal control adults (NC) participated. Executive function (set-shifting) and walking were assessed singly and during dual tasking. Results Dual tasking had a significant effect on cognition (reduced set-shifting) and on walking (speed, stride length) for both PD and NC, and also on stride frequency for PD only. The impact of dual tasking on walking speed and stride frequency was significantly greater for PD than NC. Though the group by condition interaction was not significant, PD had fewer set-shifts than NC on dual task. Further, relative to NC, PD showed significantly greater variability in cognitive performance under dual tasking, whereas variability in motor performance remained unaffected by dual tasking. Conclusions Dual tasking had a significantly greater effect in PD than in NC on cognition as well as on walking. The results suggest that assessment and treatment of PD should consider the cognitive as well as the gait components of PD-related deficits under dual-task conditions.

Objective: The burden of PD extends beyond physical limitations and includes significant psychosocial adjustments as individuals undergo changes to their self-perception and how others perceive them. There is limited quantitative evidence of the factors that contribute to selfperceived stigma, which we addressed in the present study. Methods:In 362 individuals with PD (157 women, 205 men), self-perceived stigma was measured by the four-item stigma subscale of the Parkinson's Disease Questionnaire (PDQ-39). Hierarchical linear modeling was used to assess predictors of stigma including demographics (age, gender) and disease characteristics: duration, stage (Hoehn & Yahr Scale), motor severity (Unified Parkinson's Disease Rating Scale, UPDRS, Part 3), activities of daily living (UPDRS Part 2), and depression (Geriatric Depression Scale). Predictor variables were chosen based on their significant correlations with the stigma subscale. Further analyses were conducted for men and women separately.Results: For the total sample, the full model accounted for 14% of the variance in stigma perception (p < .001). Younger age and higher depression scores were the only significant predictors (both p<.001). This pattern was also seen for the men in the sample. For the women, only depression was a significant predictor. Depression mediated the relation between stigma and activities of daily living.

The program may hold promise as an effective nonpharmacological intervention for apathy in PD. Implications and future directions are discussed. Randomized controlled trials are needed.