The objectives were to conduct a meta-analysis in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) standards to determine effect sizes (Cohen’s d) for cognitive dysfunction in adults with type 2 diabetes, relative to nondiabetic controls, and to obtain effect sizes for the most commonly reported neuropsychological tests within domains. Twenty-four studies, totaling 26,137 patients (n = 3351 with diabetes), met study inclusion criteria. Small to moderate effect sizes were obtained for five of six domains: motor function (3 studies, n = 2374; d = −0.36), executive function (12 studies, n = 1784; d = −0.33), processing speed (16 studies, n = 3076; d = −0.33), verbal memory (15 studies, n = 4,608; d = −0.28), and visual memory (6 studies, n = 1754; d = −0.26). Effect size was smallest for attention/concentration (14 studies, n = 23,143; d = −0.19). The following tests demonstrated the most notable performance decrements in diabetes samples: Grooved Pegboard (dominant hand) (d = −0.60), Rey Auditory Verbal Learning Test (immediate) (d = −0.40), Trails B (d = −0.39), Rey-Osterreith Complex Figure (delayed) (d = −0.38), Trails A (d = −0.34), and Stroop Part I (d = −0.28). This study provides effect sizes to power future epidemiological and clinical diabetes research studies examining cognitive function and to help inform the selection of neuropsychological tests.

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Hypertension affects a large proportion of urban African-American older adults. While there have been great strides in drug development, many older adults do not have access to such medicines or do not take them. Mindfulness-based stress reduction (MBSR) has been shown to decrease blood pressure in some populations. This has not been tested in low-income, urban African-American older adults. Therefore, the primary purpose of this pilot study was to test the feasibility and acceptability of a mindfulness-based program for low income, minority older adults provided in residence. The secondary purpose was to learn if the mindfulness-based program produced differences in blood pressure between the intervention and control groups. Participants were at least 62 years old and residents of a low-income senior residence. All participants were African-American, and one was male. Twenty participants were randomized to the mindfulness-based intervention or a social support control group of the same duration and dose. Blood pressure was measured with the Omron automatic blood pressure machine at baseline and at the end of the 8-week intervention. A multivariate regression analysis was performed on the difference in scores between baseline and post-intervention blood pressure measurements, controlling for age, education, smoking status, and anti-hypertensive medication use. Effect sizes were calculated to quantify the magnitude of the relationship between participation in the mindfulness-based intervention and the outcome variable, blood pressure. Attendance remained 980% in all 8 weeks of both the intervention and the control groups. The average systolic blood pressure decreased for both groups post-intervention. Individuals in the intervention group exhibited a 21.92-mmHg lower systolic blood pressure compared to the social support control group post-intervention and this value was statistically significant (p=0.020). The average diastolic blood pressure decreased in the intervention group postintervention, but increased in the social support group. Individuals in the intervention group exhibited a 16.70-mmHg lower diastolic blood pressure compared to the social support group post-intervention, and this value was statistically significant (p=0.003). Older adults are at a time in life when a reflective, stationary intervention, delivered in residence, could be an appealing mechanism to improve blood pressure. Given our preliminary results, larger trials in this hypertensive study population are warranted.

Objective To perform a systematic review and meta-analysis that quantitatively tests and summarizes the hypothesis that depression results in elevated oxidative stress and lower antioxidant levels. Methods We performed a meta-analysis of studies that reported an association between depression and oxidative stress and/or antioxidant status markers. PubMed and EMBASE databases were searched for articles published from January 1980 through December 2012. A random-effects model, weighted by inverse variance, was performed to pool standard deviation (Cohen’s d) effect size estimates across studies for oxidative stress and antioxidant status measures, separately. Results Twenty-three studies with 4980 participants were included in the meta-analysis. Depression was most commonly measured using the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition criteria. A Cohen’s d effect size of 0.55 (95% confidence interval = 0.47–0.63) was found for the association between depression and oxidative stress, indicating a roughly 0.55 of 1-standard-deviation increase in oxidative stress among individuals with depression compared with those without depression. The results of the studies displayed significant heterogeneity (I2 = 80.0%, p < .001). A statistically significant effect was also observed for the association between depression and antioxidant status markers (Cohen’s d = −0.24, 95% confidence interval = −0.33 to −0.15). Conclusions This meta-analysis observed an association between depression and oxidative stress and antioxidant status across many different studies. Differences in measures of depression and markers of oxidative stress and antioxidant status markers could account for the observed heterogeneity. These findings suggest that well-established associations between depression and poor heath outcomes may be mediated by high oxidative stress.