The impact of leisure participation on mental health for older people with depression: a systematic review

Aims: This systematic review aimed to discover whether participation in individually chosen leisure activities improved mental health for people aged over 65 who have depression. Methods: Twenty-six potentially relevant studies were identified from an electronic database review. Of these 12 met the inclusion criteria and scope of the review. Results: The current evidence base is relatively small, and includes a diversity of subject groups, subject situations, and study designs. In all cases, participants were either directed to choose from a number of leisure activities, or provided with a pre-designed program that did not allow for individual choice. Conclusion: Currently, there is insufficient evidence available to determine whether participation in individually chosen leisure activities improves mental health for people aged over 65 who have depression.

Diabetes prevention research: a systematic review of external validity in lifestyle interventions

Context

Type 2 diabetes is a major contributor to disease burden globally. A number of systematic reviews support the efficacy of lifestyle interventions in preventing Type 2 diabetes in adults; however, relatively little attention has been paid to the generalizability of study findings. This study systematically reviews the reporting of external validity components and generalizability of diabetes prevention studies.

Evidence acquisition

Lifestyle intervention studies for the prevention of Type 2 diabetes in adults with at least 6 months' follow-up, published between 1990 and 2011, were identified through searches of major electronic databases. External validity reporting was rated using an assessment tool, and all analysis was undertaken in 2011.

Evidence synthesis

A total of 31 primary studies (n=95 papers) met the selection criteria. All studies lacked full reporting on external validity elements. Description of the study sample, intervention, delivery agents, and participant attrition rates were reported by most studies. However, few studies reported on the representativeness of individuals and settings, methods for recruiting settings and delivery agents, costs, and how interventions could be institutionalized into routine service delivery. It is uncertain to what extent the findings of diabetes prevention studies apply to men, socioeconomically disadvantaged individuals, those living in rural and remote communities, and to low- and middle-income countries.

Conclusions

Reporting of external validity components in diabetes prevention studies needs to be enhanced to improve the evidence base for the translation and dissemination of these programs into policy and practice.

Leptin in bipolar disorder: a systematic review and meta-analysis

BACKGROUND: Bipolar disorder (BD) is a psychiatric disorder associated with increased rates of obesity and inflammation. Leptin is an adipokine that is mainly produced by the white adipose tissue in response to insulin. It stimulates the immune system, increasing the production of pro-inflammatory cytokines. There is currently uncertainty regarding possible alterations in peripheral leptin levels across the mood states in BD. METHODS: This study comprises a between-group meta-analysis comparing serum and plasma leptin levels in people with BD in mania, depression or euthymia and healthy controls. We conducted a systematic search for all possibly eligible-English and non-English peer-reviewed articles. We calculated the effect size (ES) utilizing Hedges' adjusted g using random effects. RESULTS: Eleven studies were included in the meta-analyses, providing data on 1118 participants. Serum and plasma leptin levels were not altered in subjects with BD when compared to healthy controls in mania (g=-0.99, 95% CI -2.43 to 0.43, P=0.171), in depression (g=0.17, 95% CI -0.45 to 0.79, P=0.584), or in euthymia (g=0.03, 95% CI -0.39 to 0.46, P=0.882). However, we did observe a stronger association between leptin levels and both age and BMI in patients with BD in euthymia compared to healthy controls, such that the greater the age of the individuals, the greater the difference in leptin levels between BD and controls; and the higher the BMI, the greater the difference in leptin levels between BD and controls. CONCLUSIONS: Our meta-analysis provides evidence that leptin levels are not altered in BD across the mood spectrum compared to healthy controls. The disproportionate increase of leptin levels with increase in BMI in BD speaks in favour of a potential inflammatory role of white adipose tissue in BD and a disproportionate increase of leptin levels with increase in age.