Sedentary behaviour can be associated with poor mental health, but it remains unclear whether all types of sedentary behaviour have equivalent detrimental effects.

To model the potential impact on depression of replacing passive with mentally active sedentary behaviours and with light and moderate-to-vigorous physical activity. An additional aim was to explore these relationships by self-report data and clinician diagnoses of depression.

In 1997, 43 863 Swedish adults were initially surveyed and their responses linked to patient registers until 2010. The isotemporal substitution method was used to model the potential impact on depression of replacing 30 min of passive sedentary behaviour with equivalent durations of mentally active sedentary behaviour, light physical activity or moderate-to-vigorous physical activity. Outcomes were self-reported depression symptoms (cross-sectional analyses) and clinician-diagnosed incident major depressive disorder (MDD) (prospective analyses).

Of 24 060 participants with complete data (mean age 49.2 years, s.d. 15.8, 66% female), 1526 (6.3%) reported depression symptoms at baseline. There were 416 (1.7%) incident cases of MDD during the 13-year follow-up. Modelled cross-sectionally, replacing 30 min/day of passive sedentary behaviour with 30 min/day of mentally active sedentary behaviour, light physical activity and moderate-to-vigorous activity reduced the odds of depression symptoms by 5% (odds ratio 0.95, 95% CI 0.94–0.97), 13% (odds ratio 0.87, 95% CI 0.76–1.00) and 19% (odds ratio 0.81, 95% CI 0.93–0.90), respectively. Modelled prospectively, substituting 30 min/day of passive with 30 min/day of mentally active sedentary behaviour reduced MDD risk by 5% (hazard ratio 0.95, 95% CI 0.91–0.99); no other prospective associations were statistically significant.

Substituting passive with mentally active sedentary behaviours, light activity or moderate-to-vigorous activity may reduce depression risk in adults.

Background: Evidence suggests that cannabis use may be associated with suicidality in adolescence. Nevertheless, very few studies have assessed this association in low- and middle-income countries (LMICs). In this cross-sectional survey, we investigated the association of cannabis use and suicidal attempts in adolescents from 21 LMICs, adjusting for potential confounders.

Method: Data from the Global school-based Student Health Survey was analyzed in 86,254 adolescents from 21 countries [mean (SD) age = 13.7 (0.9) years; 49.0% girls]. Suicide attempts during past year and cannabis during past month and lifetime were assessed. Multivariable logistic regression analyses were conducted.

Results: The overall prevalence of past 30-day cannabis use was 2.8% and the age-sex adjusted prevalence varied from 0.5% (Laos) to 37.6% (Samoa), while the overall prevalence of lifetime cannabis use was 3.9% (range 0.5%–44.9%). The overall prevalence of suicide attempts during the past year was 10.5%. Following multivariable adjustment to potential confounding variables, past 30-day cannabis use was significantly associated with suicide attempts (OR = 2.03; 95% CI: 1.42–2.91). Lifetime cannabis use was also independently associated with suicide attempts (OR = 2.30; 95% CI: 1.74–3.04).

Conclusion: Our data indicate that cannabis use is associated with a greater likelihood for suicide attempts in adolescents living in LMICs. The causality of this association should be confirmed/refuted in prospective studies to further inform public health policies for suicide prevention in LMICs.

Despite the benefits of being active for people with mild cognitive impairment (MCI) on cognition and the acknowledgement that MCI is a critical period for intervening to prevent dementia, little is known about the actual sedentary levels in people with MCI. This study investigates correlates of sedentary behavior (SB) in people with MCI.

This was a cross-sectional study.

Data from the World Health Organization’s Study on Global Ageing and Adult Health were analyzed.

Individuals aged ≥50 years with MCI were included.

SB was assessed by the Global Physical Activity Questionnaire. Associations between SB levels and the correlates were examined using multivariable linear and logistic regressions.

4,082 individuals aged ≥50 years with MCI (64.4 ± 17.0 years; 55.1% female) were included. The prevalence of high SB (i.e., ≥8 hours/day) was 14.0% (95%CI = 12.2%–16.0%), while the time spent sedentary was 262 ± 290 minutes/day. Correlates significantly associated with being sedentary ≥8 hours/day and time spent sedentary per day were, older age, being unemployed, depression, sleep problems, obesity (vs. normal weight), diabetes, stroke, poor self-rated health, and lower levels of social cohesion.

Future research exploring interventions to reduce SB in people with MCI should target the identified sociodemographic and mental and physical health correlates, while the promotion of social cohesion may have the potential to increase the efficacy of future public health initiatives.

Exercise improves cardiorespiratory fitness (CRF) and reduces depressive symptoms in people with depression. It is unclear if changes in CRF are a predictor of the antidepressant effect of exercise in people with depression.

To investigate whether an increase in CRF is a predictor of depression severity reduction after 12 weeks of exercise (trial registration: DRKS study ID, DRKS00008745).

The present study includes participants who took part in vigorous (n = 33), moderate (n = 38) and light (n = 39) intensity exercise and had CRF information (as predicted maximal oxygen uptake, V̇O2max) collected before and after the intervention. Depression severity was measured with the Montgomery–Åsberg Depression Rating Scale (MADRS). V̇O2max (L/min) was assessed with the Åstrand–Rhyming submaximal cycle ergometry test. The main analysis was conducted pooling all exercise intensity groups together.

All exercise intensities improved V̇O2max in people with depression. Regardless of frequency and intensity of exercise, an increase in post-treatment V̇O2max was significantly associated with reduced depression severity at follow-up (B = −3.52, 95% CI −6.08 to −0.96); adjusting for intensity of exercise, age and body mass index made the association stronger (B = −3.89, 95% CI −6.53 to −1.26). Similarly, increased V̇O2max was associated with higher odds (odds ratio = 3.73, 95% CI 1.22–11.43) of exercise treatment response (≥50% reduction in MADRS score) at follow-up.

Our data suggest that improvements in V̇O2max predict a greater reduction in depression severity among individuals who were clinically depressed. This finding indicates that improvements in V̇O2max may be a marker for the underpinning biological pathways for the antidepressant effect of exercise.

None.

Given the important health benefits of physical activity (PA) and the higher risk for physical inactivity in people with anxiety, and the high prevalence of anxiety and low PA among the elderly, there is a need for research to investigate what factors influence PA participation among anxious older individuals. We investigated PA correlates among community-dwelling adults aged ≥ 65 years with anxiety symptoms in six low- and middle-income countries.

Cross-sectional data from the World Health Organization's Study on Global Ageing and Adult Health were analyzed. PA level was assessed by the Global Physical Activity Questionnaire. 980 participants with anxiety (mean age 73.3 years; 62.4% females) were grouped into those who do and do not (low PA) meet the 150 minutes of moderate-to-vigorous PA per week recommendation. Associations between PA and the correlates were examined using multivariable logistic regressions.

The prevalence of low PA was 44.9% (95% CI = 39.2–50.7%). Older age, male gender, less consumption of alcohol, mild cognitive impairment, pain, a wide range of somatic co-morbidities, slow gait, weak grip strength, poor self-rated health, and lower levels of social cohesion were identified as significant positive correlates of low PA.

Our data illustrate that a number of sociodemographic and health factors are associated with PA levels among older people with symptoms of anxiety. The promotion of social cohesion may increase the efficacy of public health initiatives, while from a clinical perspective, somatic co-morbidities, cognitive impairment, pain, muscle strength, and slow gait need to be considered.