Study Title and Description
Coffee, caffeine, and risk of depression among women.
Key Questions Addressed
|1||For [population], is caffeine intake above [exposure dose], compared to intakes [exposure dose] or less, associated with adverse effects on behavior*?|
Primary Publication Information
|Title||Coffee, caffeine, and risk of depression among women.|
|Author||M Lucas,F Mirzaei,A Pan,OI Okereke,WC Willett,ÉJ O'Reilly,K Koenen,A Ascherio,|
Secondary Publication Information
There are currently no secondary publications defined for this study.
Extraction Form: Behavior - Design Details - INCLUDED Studies
No arms have been defined in this extraction form.
|Question... Follow Up||Answer||Follow-up Answer|
|What outcome is being evaluated in this paper?||Behavior|
|What is the objective of the study (as reported by the authors)?||Thus, we accessed data from the Nurses’ Health Study, a large cohort of women, to examine prospectively whether caffeine consumption or intake of certain caffeine-containing beverages is associated with the risk of depression.|
|Provide a general description of the methods as reported by the authors. Information should be extracted based on relevance to the SR (i.e., caffeine related methods)||The Nurses’ Health Study is a prospective cohort of 121,700 U.S. female registered nurses aged 30 to 55 years at enrollment in 1976. Every 2 years, participants provide updated information, via mailed questionnaires, about lifestyle, medical history and newly-diagnosed medical illnesses. A total of 50,931 women were considered depression-free in 1996 and comprised the baseline population for the current analyses. After excluding those who had missing values for exposure variables (N=192), the final 1996 baseline population comprised 50,739 women. In 1980, 1984, 1986, 1990, 1994, 1998 and 2002, caffeine consumption and other dietary variables among participants were assessed using a semi-quantitative food-frequency questionnaire. Among items of these questionnaires were coffee ("coffee with caffeine" and "decaffeinated coffee"), tea ("non herbal tea"), soft drinks with caffeine (sugared or low calorie Coke, Pepsi, or other cola), soft drinks without caffeine (sugared or low-calorie caffeine-free Coke, Pepsi, or other carbonated beverage, e.g. 7-Up), and chocolate. Consumptions of nutrients and caffeine were calculated, as described elsewhere, primarily using concurrent U.S. Department of Agriculture food composition data. In these calculations, we assumed that the content of caffeine was 137 mg per cup of coffee, 47 mg per cup of tea, 46 mg per can or bottle of soft drink, and 7 mg per serving of chocolate. Incident depression was defined as reporting both a new physician-diagnosed depression and beginning regular antidepressant use (i.e. used regularly in past 2 years). Instead of using a single measurement, and to reduce random measurement error, analyses were conducted using the cumulative average of caffeine consumption from all the available questionnaires prior to the beginning of each 2-year period follow-up. Since our last food frequency questionnaire used before baseline was in 1994, our analyses imply a latency of exposure of 2-year minimum. For example, the cumulative average of caffeine consumption information of 1980 through 1994 was used to predict clinical depression episode in 1996–1998, consumptions of 1980 through 1994 for 1998–2000 follow-up period, intakes of 1980 through 1998 for 2000–2002 follow-up period, and so on.|
|How many outcome-specific endpoints are evaluated?||1|
|What is the (or one of the) endpoint(s) evaluated? (Each endpoint listed separately)||Clinical depression|
|List additional health endpoints (separately).|
|List additional health endpoints (separately)|
|Notes||Incident depression was defined as reporting both a new physician-diagnosed depression and beginning regular antidepressant use (i.e. used regularly in past 2 years).|
|What is the study design?||Cohort|
|Randomized or Non-Randomized?|
|What were the diagnostics or methods used to measure the outcome?||Objective|
|Optional: Name of Method or short description||physician-diagnosed depression|
|What was the reference, comparison, or control group(s)? (e.g. high vs low consumption, number of cups, etc.)||Consumption of <100 mg/d vs 100-250, 250-400, 400-550, or ≥550 mg/d caffeine|
|What were the listed confounders or modifying factors as stated by the authors? (e.g. multi-variable components of models. Copy from methods)||Adjusted for age (continuous), time interval, total energy intake (continuous), current menopausal hormones (binary), smoking status (never smoked, past smoker, current smoker), body-mass index (<25, 25–29.9, ≥30 kg/m2), physical activities (quintiles), marital status (married/partnership, widowed, separated/divorced/single), not involve in social or community group (binary), retired (binary), reported diagnosis of diabetes (binary), cancer (binary), high blood pressure (binary), myocardial infarction or angina (binary) and for Mental Health Index-5 score (86–100, 76–85, 53–75) in 1996.|
|Provide a general description of results (as reported by the authors).||Compared to the lowest caffeine consumption group (<100 mg/d), multivariate relative risk for depression was 0.80 (95% CI, 0.68 to 0.95) for women in the highest caffeine consumption group (≥550 mg/d).|
|Did the authors perform a dose-response analysis (or trend/related analysis)?||Yes|
|What were the authors's observations re: trend analysis?||There was an inverse dose-response relationship between caffeine consumption and depression risk in our multivariate model (P for trend=0.02, Figure 1).|
|What were the author's conclusions?||In this large prospective cohort of older women free from clinical depression or severe depressive symptoms at baseline, risk of depression decreased in a dose-dependent manner with increasing consumption of caffeinated coffee.|
|What were the sources of funding?||The study was supported by National Institutes of Health (NIH) Grant DK58845. Dr Ascherio received a grant from the National Alliance for Research on Schizophrenia & Depression (Project ID: 5048070–01) and was supported by R01 NS061858. Dr Lucas received a postdoctoral fellowship from the Fonds de recherche en santé du Québec (FRSQ). The funding sources were not involved in data collection, data analysis, manuscript writing and publication.|
|What conflicts of interest were reported?||None reported|
|Does the exposure (dose) need to be standardized to the SR?||No|
|Provide calculations/conversions for the exposure based on the decision tree in the guide (for all endpoints/exposure levels of interest).|
|List all the endpoint(s) followed by the dose (mg) which will be used in comparison to Nawrot. Characterize value as LOAEL/NOAEL, etc. if possible.||Depression NOAEL ≥ 550 mg/d|
|Notes regarding selection/listing of endpoints and exposures/doses to be compared to Nawrot.||Risk of depression decreased as consumption increased.|
|What is the importance of the study with respect to the adverseness of the outcome?||Critcal|
No baseline characteristics have been defined for this extraction form.
Results & Comparisons
No Results found.
|Arm or Total||Title||Description||Comments|
No quality dimensions were specified.
No quality rating data was found.