G-52

The high global prevalence of depression, together with the recent acceleration of remote care owing to the COVID-19 pandemic, has prompted increased interest in the efficacy of digital interventions for the treatment of depression. We provide a summary of the latest evidence base for digital interventions in the treatment of depression based on the largest study sample to date. A systematic literature search identified 83 studies (N = 15,530) that randomly allocated participants to a digital intervention for depression versus an active or inactive control condition. Overall heterogeneity was very high (I2 = 84%). Using a random-effects multilevel metaregression model, we found a significant medium overall effect size of digital interventions compared with all control conditions (g = .52). Subgroup analyses revealed significant differences between interventions and different control conditions (WLC: g = .70; attention: g = .36; TAU: g = .31), significantly higher effect sizes in interventions that involved human therapeutic guidance (g = .63) compared with self-help interventions (g = .34), and significantly lower effect sizes for effectiveness trials (g = .30) compared with efficacy trials (g = .59). We found no significant difference in outcomes between smartphone-based apps and computer- and Internet-based interventions and no significant difference between human-guided digital interventions and face-to-face psychotherapy for depression, although the number of studies in both comparisons was low. Findings from the current meta-analysis provide evidence for the efficacy and effectiveness of digital interventions for the treatment of depression for a variety of populations. However, reported effect sizes may be exaggerated because of publication bias, and compliance with digital interventions outside of highly controlled settings remains a significant challenge. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

Cognitive Behavioural Therapy (CBT) is effective in treating Social Anxiety Disorder (SAD). However, less is known about whether gains achieved in disorder-specific and secondary outcomes (e.g., depression, general anxiety, quality of life, and self-esteem) are maintained 12 months or longer. A systematic literature search yielded 25 relevant studies that administered CBT to participants with SAD. Multivariate meta-analyses of post-treatment assessments, found that CBT was superior to control conditions in reducing social anxiety (g =.74), depression (g =.52), general anxiety (g =.69) and improving quality of life (g =.39). The within-groups effect sizes revealed that 12 months or more after CBT treatment, symptoms continued to improve for social anxiety (gav =.23) and quality of life (gav =.17), and gains were maintained for depressive (gav =.06) and general anxiety symptoms (gav =.03). However, meta-analyses of long-term outcomes lack comparison groups. Moderation was non-significant for the treatment model, format, number of sessions, treatment duration, or inclusion of booster sessions. Future research may investigate what drives improvement after treatment cessation and how CBT affects other co-occurring symptomatology. Taken together, CBT produces many benefits for SAD and individuals with co-occurring symptoms can benefit from extant SAD-focused treatments.

Slow oxidative muscle, most notably the soleus, is inherently well equipped with the molecular machinery for regulating blood-borne substrates. However, the entire human musculature accounts for only ~15% of the body's oxidative metabolism of glucose at the resting energy expenditure, despite being the body's largest lean tissue mass. We found the human soleus muscle could raise local oxidative metabolism to high levels for hours without fatigue, during a type of soleus-dominant activity while sitting, even in unfit volunteers. Muscle biopsies revealed there was minimal glycogen use. Magnifying the otherwise negligible local energy expenditure with isolated contractions improved systemic VLDL-triglyceride and glucose homeostasis by a large magnitude, e.g., 52% less postprandial glucose excursion (~50 mg/dL less between ~1 and 2 h) with 60% less hyperinsulinemia. Targeting a small oxidative muscle mass (~1% body mass) with local contractile activity is a potent method for improving systemic metabolic regulation while prolonging the benefits of oxidative metabolism.