Context Several studies have suggested that depression is associated with an increased risk of stroke; however, the results are inconsistent. Objective To conduct a systematic review and meta-analysis of prospective studies assessing the association between depression and risk of developing stroke in adults. Data Sources A search of MEDLINE, EMBASE, and PsychINFO databases (to May 2011) was supplemented by manual searches of bibliographies of key retrieved articles and relevant reviews. Study Selection We included prospective cohort studies that reported risk estimates of stroke morbidity or mortality by baseline or updated depression status assessed by self-reported scales or clinician diagnosis. Data Extraction Two independent reviewers extracted data on depression status at baseline, risk estimates of stroke, study quality, and methods used to assess depression and stroke. Hazard ratios (HRs) were pooled using fixed-effect or random-effects models when appropriate. Associations were tested in subgroups representing different participant and study characteristics. Publication bias was evaluated with funnel plots and Begg test. Results The search yielded 28 prospective cohort studies (n = 317540 participants) that reported 8478 stroke cases (morbidity and mortality) during a follow-up period ranging from 2 to 29 years. The pooled adjusted HRs were 1.45 (95% confidence interval [CI], 1.29–1.63; P-for-heterogeneity <0.001; random-effects model) for total stroke, 1.55 (1.25–1.93; P-for-heterogeneity = 0.31; fixed-effects model) for fatal stroke (8 studies), and 1.25 (1.11–1.40; P-for-heterogeneity = 0.34; fixed-effects model) for ischemic stroke (6 studies). The estimated absolute risk differences associated with depression were 106 cases for total stroke, 53 cases for ischemic stroke, and 22 cases for fatal stroke per 100 000 individuals per year. The increased risk of total stroke associated with depression was consistent across most subgroups. Conclusion Depression is associated with a significantly increased risk of stroke morbidity and mortality.

OBJECTIVEEpidemiological studies have repeatedly investigated the association between depression and metabolic syndrome (MetS). However, the results have been inconsistent. This meta-analysis aimed to summarize the current evidence from cross-sectional and prospective cohort studies that evaluated this association.RESEARCH DESIGN AND METHODSMEDLINE, EMBASE, and PsycINFO databases were searched for articles published up to January 2012. Cross-sectional and cohort studies that reported an association between the two conditions in adults were included. Data on prevalence, incidence, unadjusted or adjusted odds ratio (OR), and 95% CI were extracted or provided by the authors. The pooled OR was calculated separately for cross-sectional and cohort studies using random-effects models. The I2 statistic was used to assess heterogeneity.RESULTSThe search yielded 29 cross-sectional studies (n = 155,333): 27 studies reported unadjusted OR with a pooled estimate of 1.42 (95% CI 1.28–1.57; I2 = 55.1%); 11 studies reported adjusted OR with depression as the outcome (1.27 [1.07–1.57]; I2 = 60.9%), and 12 studies reported adjusted OR with MetS as the outcome (1.34 [1.18–1.51]; I2 = 0%). Eleven cohort studies were found (2 studies reported both directions): 9 studies (n = 26,936 with 2,316 new-onset depression case subjects) reported adjusted OR with depression as the outcome (1.49 [1.19–1.87]; I2 = 56.8%), 4 studies (n = 3,834 with 350 MetS case subjects) reported adjusted OR with MetS as the outcome (1.52 [1.20–1.91]; I2 = 0%).CONCLUSIONSOur results indicate a bidirectional association between depression and MetS. These results support early detection and management of depression among patients with MetS and vice versa.

Background Caffeine is the world’s most widely used central nervous system stimulant, with about 80% consumed in form of coffee. However, studies that analyzed prospectively the relation of coffee or caffeine consumption and depression risk are scarce. Methods A total of 50,739 U.S. women (mean age=63 years) free from depressive symptoms at baseline (1996) were prospectively followed until 2006. Caffeine and coffee consumption, and other caffeinated and decaffeinated beverages, were obtained from validated questionnaires completed between 1980 through 2002 and computed as cumulative average of consumption with a 2-year latency applied. Clinical depression was defined as reporting both physician-diagnosed depression and antidepressant use. Relative risks of clinical depression were estimate using Cox proportional hazards regression models. Results During 10 years of follow-up (1996–2006), 2,607 incident cases of depression were identified. Compared to women consuming caffeinated coffee less frequently (≤1 cup/wk), multivariate relative risk of depression was 0.85 (95% confidence interval [CI], 0.75 to 0.95) for those consuming 2–3 cups/d and 0.80 (95%CI, 0.64 to 0.99; P trend <0.001) for those consuming ≥4 cups/d. Multivariate relative risk for depression was 0.80 (95%CI, 0.68 to 0.95; P trend=0.02) for women in the highest (≥550 mg/d) vs. lowest (<100 mg/d) of the 5 caffeine consumption categories. Decaffeinated coffee was not associated with depression risk. Conclusions In this large longitudinal study we found that depression risk decreases with increasing caffeinated coffee consumption. Further investigations are needed to confirm this finding and to determine whether usual caffeinated coffee consumption may contribute to depression prevention.

Objective To determine whether higher past exposure to particulate air pollution is associated with prevalent high symptoms of anxiety. Design Observational cohort study. Setting Nurses’ Health Study. Participants 71 271 women enrolled in the Nurses’ Health Study residing throughout the contiguous United States who had valid estimates on exposure to particulate matter for at least one exposure period of interest and data on anxiety symptoms. Main outcome measures Meaningfully high symptoms of anxiety, defined as a score of 6 points or greater on the phobic anxiety subscale of the Crown-Crisp index, administered in 2004. Results The 71 271 eligible women were aged between 57 and 85 years (mean 70 years) at the time of assessment of anxiety symptoms, with a prevalence of high anxiety symptoms of 15%. Exposure to particulate matter was characterized using estimated average exposure to particulate matter <2.5 μm in diameter (PM 2.5 ) and 2.5 to 10 μm in diameter (PM 2.5-10 ) in the one month, three months, six months, one year, and 15 years prior to assessment of anxiety symptoms, and residential distance to the nearest major road two years prior to assessment. Significantly increased odds of high anxiety symptoms were observed with higher exposure to PM 2.5 for multiple averaging periods (for example, odds ratio per 10 µg/m 3 increase in prior one month average PM 2.5 : 1.12, 95% confidence interval 1.06 to 1.19; in prior 12 month average PM 2.5 : 1.15, 1.06 to 1.26). Models including multiple exposure windows suggested short term averaging periods were more relevant than long term averaging periods. There was no association between anxiety and exposure to PM 2.5-10 . Residential proximity to major roads was not related to anxiety symptoms in a dose dependent manner. Conclusions Exposure to fine particulate matter (PM 2.5 ) was associated with high symptoms of anxiety, with more recent exposures potentially more relevant than more distant exposures. Research evaluating whether reductions in exposure to ambient PM 2.5 would reduce the population level burden of clinically relevant symptoms of anxiety is warranted.