Study Title and Description
Caffeine, cognitive failures and health in a non-working community sample.
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||Caffeine, cognitive failures and health in a non-working community sample.|
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)?||Secondary analyses of a large epidemiological database (N=3223 non-working participants, 57% female, with a mean age of 49.6 years, range 17–92 years) were conducted to examine associations between caffeine consumption (mean caffeine consumption was 140 mg/day, range 0–1800 mg) and cognitive failures (errors of memory, attention and action) in a non-working sample. Associations between caffeine consumption and physical and mental health problems were also examined.|
|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)||This involved a secondary analysis of a database formed by combining the Bristol Stress and Health at Work study and the Cardiff Health and Safety at Work study. Details of the database are given in Smith et al. (2003) and Smith (2005b). This database contained information on level of caffeine consumption, cognitive failures and health outcomes. In addition, it contained information about possible confounders that need to be controlled in such analyses (e.g. demographics and health-related behaviours—see Wadsworth et al., 2003). Caffeine consumption The participants provided information on their normal daily consumption of caffeinated drinks and their daily consumption was calculated using the values given by Barone and Roberts (1996). Caffeine from other sources (e.g. chocolate or medication) was not recorded. Health outcomes This section of the questionnaire consisted of four parts. The third involved mental health outcomes (anxiety and depression, measured by the Hospital Anxiety and Depression Scale, Zigmond and Snaith, 1983). Finally, use of health services was measured by visits to the GP, hospital outpatient attendance and whether or not the person had been a hospital in-patient. SAMPLE The sample consisted of 3223 non-working participants (57% female) with a mean age of 49.6 years (SD 21.9; range 17–92 years). Mean caffeine consumption was 140 mg/day (SD 171; range 0–1800 mg). STATISTICAL ANALYSES Initial analyses involved univariate cross-tabulations and logistic regressions to examine associations between caffeine consumption (split into quartiles) and the outcomes. Potential confounders were then entered into a series of multi-variate logistic regressions and the adjusted odds ratios presented. In the logistic regressions non-consumption of caffeine was set as the reference category. The significance of individual comparisons can be seen from the adjusted odds ratios and confidence levels.|
|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)|
|What is the study design?||Cross-sectional|
|Randomized or Non-Randomized?|
|What were the diagnostics or methods used to measure the outcome?||Subjective|
|Optional: Name of Method or short description||Hospital Anxiety and Depression Scale|
|Caffeine (general)||Caffeine (general)|
|What was the reference, comparison, or control group(s)? (e.g. high vs low consumption, number of cups, etc.)||0 mg/day vs 1-140 mg/day, 141-260 mg/day, > 260 mg/day|
|What were the listed confounders or modifying factors as stated by the authors? (e.g. multi-variable components of models. Copy from methods)||demographics and health-related behaviours|
|Provide a general description of results (as reported by the authors).||Recurrent illness over the last 12 months. None of the health outcomes were significantly associated with caffeine consumption except for clinical depression. Higher caffeine consumption was associated with a reduced risk of depression ( p<0.005; 1–140 mg/day: OR=0.32 CI 0.2, 0.5; 141–260 mg/day: OR=0.18 CI¼0.1, 0.3; >260 mg/day: OR=0.12 CI: 0.1, 0.2).|
|Did the authors perform a dose-response analysis (or trend/related analysis)?||No|
|What were the authors's observations re: trend analysis?|
|What were the author's conclusions?||Indeed, the only effect of caffeine on life-time prevalence of disease was found for angina and the only 12-month health effect that remained significant was depression, with higher caffeine consumption being associated with reduced risk of angina and clinical depression. Indeed, the present results suggest that consumption of caffeine is associated with both better cognitive functioning and mental health.|
|What were the sources of funding?||Professor Smith’s research on caffeine has been supported by the Institute for Scientific Information on Coffee.|
|What conflicts of interest were reported?||N/A|
|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 (clinical) - NOAEL = >260 mg/day|
|Notes regarding selection/listing of endpoints and exposures/doses to be compared to Nawrot.||caffeine reduced the risk of suffering from clinical depression|
|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.