exercise

Importance: Obesity affects approximately 21% of US adolescents and is associated with insulin resistance, hypertension, dyslipidemia, sleep disorders, depression, and musculoskeletal problems. Obesity during adolescence has also been associated with an increased risk of mortality from cardiovascular disease and type 2 diabetes in adulthood.

Observations: Obesity in adolescents aged 12 to younger than 18 years is commonly defined as a body mass index (BMI) at the 95th or greater age- and sex-adjusted percentile. Comprehensive treatment in adolescents includes lifestyle modification therapy, pharmacotherapy, and metabolic and bariatric surgery. Lifestyle modification therapy, which includes dietary, physical activity, and behavioral counseling, is first-line treatment; as monotherapy, lifestyle modification requires more than 26 contact hours over 1 year to elicit approximately 3% mean BMI reduction. Newer antiobesity medications, such as liraglutide, semaglutide, and phentermine/topiramate, in combination with lifestyle modification therapy, can reduce mean BMI by approximately 5% to 17% at 1 year of treatment. Adverse effects vary, but severe adverse events from these newer antiobesity medications are rare. Surgery (Roux-en-Y gastric bypass and vertical sleeve gastrectomy) for severe adolescent obesity (BMI ≥120% of the 95th percentile) reduces mean BMI by approximately 30% at 1 year. Minor and major perioperative complications, such as reoperation and hospital readmission for dehydration, are experienced by approximately 15% and 8% of patients, respectively. Determining the long-term durability of all obesity treatments warrants future research.

Conclusions and relevance: The prevalence of adolescent obesity is approximately 21% in the US. Treatment options for adolescents with obesity include lifestyle modification therapy, pharmacotherapy, and metabolic and bariatric surgery. Intensive lifestyle modification therapy reduces BMI by approximately 3% while pharmacotherapy added to lifestyle modification therapy can attain BMI reductions ranging from 5% to 17%. Surgery is the most effective intervention for adolescents with severe obesity and has been shown to achieve BMI reduction of approximately 30%.

Objective. The systematic review assessed evidence on the diagnosis, treatment, and monitoring of attention deficit hyperactivity disorder (ADHD) in children and adolescents to inform a planned update of the American Academy of Pediatrics (AAP) guidelines.

Data sources. We searched PubMed®, Embase®, PsycINFO®, ERIC, clinicaltrials.gov, and prior reviews for primary studies published since 1980. The report includes studies published to June 15, 2023.

Review methods. The review followed a detailed protocol and was supported by a Technical Expert Panel. Citation screening was facilitated by machine learning; two independent reviewers screened full text citations for eligibility. We abstracted data using software designed for systematic reviews. Risk of bias assessments focused on key sources of bias for diagnostic and intervention studies. We conducted strength of evidence (SoE) and applicability assessments for key outcomes. The protocol for the review has been registered in PROSPERO (CRD42022312656).

Results. Searches identified 23,139 citations, and 7,534 were obtained as full text. We included 550 studies reported in 1,097 publications (231 studies addressed diagnosis, 312 studies addressed treatment, and 10 studies addressed monitoring). Diagnostic studies reported on the diagnostic performance of numerous parental ratings, teacher rating scales, teen/child self-reports, clinician tools, neuropsychological tests, EEG approaches, imaging, and biomarkers. Multiple approaches showed promising diagnostic performance (e.g., using parental rating scales), although estimates of performance varied considerably across studies and the SoE was generally low. Few studies reported estimates for children under the age of 7. Treatment studies evaluated combined pharmacological and behavior approaches, medication approved by the Food and Drug Administration, other pharmacologic treatment, psychological/behavioral approaches, cognitive training, neurofeedback, neurostimulation, physical exercise, nutrition and supplements, integrative medicine, parent support, school interventions, and provider or model-of-care interventions. Medication treatment was associated with improved broadband scale scores and ADHD symptoms (high SoE) as well as function (moderate SoE), but also appetite suppression and adverse events (high SoE). Psychosocial interventions also showed improvement in ADHD symptoms based on moderate SoE. Few studies have evaluated combinations of pharmacological and youth-directed psychosocial interventions, and we did not find combinations that were systematically superior to monotherapy (low SoE). Published monitoring approaches for ADHD were limited and the SoE is insufficient.

Conclusion. Many diagnostic tools are available to aid the diagnosis of ADHD, but few monitoring strategies have been studied. Medication therapies remain important treatment options, although with a risk of side effects, as the evidence base for psychosocial therapies strengthens and other nondrug treatment approaches emerge.

The primary purpose of this narrative review was to evaluate the current literature and to provide further insight into the role physical inactivity plays in the development of chronic disease and premature death. We confirm that there is irrefutable evidence of the effectiveness of regular physical activity in the primary and secondary prevention of several chronic diseases (e.g., cardiovascular disease, diabetes, cancer, hypertension, obesity, depression and osteoporosis) and premature death. We also reveal that the current Health Canada physical activity guidelines are sufficient to elicit health benefits, especially in previously sedentary people. There appears to be a linear relation between physical activity and health status, such that a further increase in physical activity and fitness will lead to additional improvements in health status.

Physical inactivity is a modifiable risk factor for cardiovascular disease and a widening variety of other chronic diseases, including diabetes mellitus, cancer (colon and breast), obesity, hypertension, bone and joint diseases (osteoporosis and osteoarthritis), and depression.1–14 The prevalence of physical inactivity (among 51% of adult Canadians) is higher than that of all other modifiable risk factors.15 In this article we review the current evidence relating to physical activity in the primary and secondary prevention of premature death from any cause, cardiovascular disease, diabetes, some cancers and osteoporosis. We also discuss the evidence relating to physical fitness and musculoskeletal fitness and briefly describe the independent effects of frequency and intensity of physical activity. (A glossary of terms related to the topic appears in Appendix 1). In a companion paper, to be published in the Mar. 28 issue, we will review how to evaluate the health-related physical fitness and activity levels of patients and will provide exercise recommendations for health.

Several authors have attempted to summarize the evidence in systematic reviews and meta-analyses. These evaluations are often overlapping (reviewing the same evidence). Some of the most commonly cited cohorts have been described in different studies over time as more data accumulate (see Appendix 2, available online at www.cmaj.ca/cgi/content/full/174/6/801/DC1). In this review, we searched the literature using the key words „physical activity,” „health,” „health status,” „fitness,” „exercise,” „chronic disease,” „mortality” and disease-specific terms (e.g., „cardiovascular disease,” „cancer,” „diabetes” and „osteoporosis”). Using our best judgment, we selected individual studies that were frequently included in systematic reviews, consensus statements and meta-analyses and considered them as examples of the best evidence available. We also have included important new findings regarding the relation between physical activity and fitness and all-cause and cardiovascular-related mortality.

The Community Preventive Services Task Force (CPSTF) recommends home-based exercise interventions to improve physical fitness (i.e., muscle strength, muscle power, muscle endurance, balance) among adults aged 65 years and older. The Physical Activity Guidelines for Americans, 2nd edition recommends older adults achieve a multicomponent physical activity regimen that combines aerobic activities with physical fitness exercises such as those used in these interventions.