ABSTRACT:

Objective:

The results from observation studies on relationship between coffee intakes and risk of depression and relationship between caffeine consumption and depression remains controversial. We conducted a meta-analysis with a dose–response analysis to quantitatively summarize the evidence about the association between coffee and caffeine intakes and risk of depression.

Method:

‍Relevant articles were identified by researching PubMed, Web of Science, China National Knowledge Infrastructure and WANFANG DATA in English or Chinese from 1 January 1980 to 1 May 2015. Case-control, cohort or cross-sectional studies evaluating coffee or caffeine consumption and depression were included. A random-effects model was used to combine study-specific relative risk and 95% confidence interval. Dose–response relationship was assessed by restricted cubic spline functions.

Results:

Data were obtained from 11 observation articles; 330,677 participants from seven studies in seven articles were included in the coffee-depression analysis, while 38,223 participants from eight studies in seven articles were involved in the caffeine-depression analysis. Compared with the lowest level consumption, the pooled relative risk (95% confidence interval) for coffee-depression and caffeine-depression was 0.757 [0.624, 0.917] and 0.721 [0.522, 0.997], respectively. For dose–response analysis, evidence of a linear association was found between coffee consumption and depression, and the risk of depression decreased by 8% (relative risk=0.92, 95% confidence interval=[0.87, 0.97], p=0.002) for each cup/day increment in coffee intake; a nonlinear association was found between caffeine consumption and depression, the risk of depression decreased faster and the association became significant when the caffeine consumption was above 68mg/day and below 509mg/day.

Conclusions:

Coffee and caffeine consumption were significantly associated with decreased risk of depression.