Advanced Search

Study Preview



Study Title and Description

Storm in a coffee cup: caffeine modifies brain activation to social signals of threat.



Key Questions Addressed
1 For [population], is caffeine intake above [exposure dose], compared to intakes [exposure dose] or less, associated with adverse effects on cardiovascular outcomes?
  • Comments Comments (
    0
    ) |

Primary Publication Information
  • Comments Comments (
    0
    ) |
TitleData
Title Storm in a coffee cup: caffeine modifies brain activation to social signals of threat.
Author JE Smith,AD Lawrence,A Diukova,RG Wise,PJ Rogers,
Country
Year 2012
Numbers

Secondary Publication Information
There are currently no secondary publications defined for this study.


Extraction Form: Cardiovascular Design
Design Details
Question... Follow Up Answer Follow-up Answer
What outcome is being evaluated in this paper? Cardiovascular
  • Comments Comments (
    0
    ) |
What is the objective of the study (as reported by the authors)? This study investigated the effects of caffeine on brain regions implicated in social threat processing and anxiety.
  • Comments Comments (
    0
    ) |
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) Weekly caffeine intake was calculated from these self-report data using dietary and manufacturers’ information on caffeine content (Heatherley et al., 2006a); for example, instant coffee 54 mg, ground coffee 105 mg, tea (bags, loose leaf, instant and green) 40 mg. These intakes were confirmed with participants on arrival at each fMRI session. Participants were restricted to individuals reporting no extreme sensitivity to caffeine (i.e. marked and distressing anxiety), but having a dietary caffeine intake of <280 mg per week, as the results of a prior study indicate this level of intake as around the threshold for withdrawal effects and tolerance (Rogers et al., 2010). Individuals reporting to have never consumed caffeine were excluded. Caffeine BP (Caffeine anhydrous powder; Direct Food Ingredients Limited, Macclesfield, Cheshire, UK) and placebo (cornflour) were administered in white size 1 cellulose capsules (Capsuline, Pompano Beach, Florida, FL, USA). These caffeine and placebo capsules were identical in appearance, and were swallowed with 50 ml of room temperature water.
  • Comments Comments (
    0
    ) |
How many outcome-specific endpoints are evaluated? 1
  • Comments Comments (
    0
    ) |
What is the (or one of the) endpoint(s) evaluated? (Each endpoint listed separately) Blood pressure (systolic and diastolic)
  • Comments Comments (
    0
    ) |
List additional health endpoints (separately). 2
  • Comments Comments (
    0
    ) |
List additional health endpoints (separately).3
  • Comments Comments (
    0
    ) |
List additional health endpoints (separately).4
  • Comments Comments (
    0
    ) |
List additional health endpoints (separately).5
  • Comments Comments (
    0
    ) |
List additional health endpoints (separately).6
  • Comments Comments (
    0
    ) |
Clinical, physiological, other Physiological
  • Comments Comments (
    0
    ) |
What is the study design? Controlled Trial
  • Comments Comments (
    0
    ) |
Randomized or Non-Randomized? NCT
  • Comments Comments (
    0
    ) |
What were the diagnostics or methods used to measure the outcome? Objective
  • Comments Comments (
    0
    ) |
Optional: Name of Method or short description Participants’ current emotional states, alertness and blood pressure were assessed outside the scanner twice: before treatment (baseline) and 2 h after receiving caffeine or placebo (post-treatment). Specific equipment not provided.
  • Comments Comments (
    0
    ) |
Caffeine (general) Caffeine (general)
  • Comments Comments (
    0
    ) |
Coffee, Chocolate, energy drink, gum, medicine/supplement, soda, tea, other?
  • Comments Comments (
    0
    ) |
Measured or self reported? Measured
  • Comments Comments (
    0
    ) |
Children, adolescents, adults, or pregnant included? Adults
  • Comments Comments (
    0
    ) |
What was the reference, comparison, or control group(s)? (e.g. high vs low consumption, number of cups, etc.) Placebo vs. caffeine exposed group.
  • Comments Comments (
    0
    ) |
What were the listed confounders or modifying factors as stated by the authors? (e.g. multi-variable components of models.  Copy from methods) Key inclusion criteria were: male, right-handed dominance, aged between 18 and 65 years, good physical and mental health, which included no current or past medical or psychiatric illness, in particular anxiety/stress disorders, hypertension and/or heart disease, and not currently receiving medication (apart from occasional aspirin or paracetamol), no MRI contraindications, current non/infrequent dietary caffeine intake (see below), willingness to attend test sessions that would include MRI scanning and the consumption of caffeine, being a non-smoker or a light smoker (</= 5 cigarettes or equivalent a day), and blood pressure within normal range (cut-offs for systolic and diastolic blood pressure were >/= 140 and >/= 90 mmHg, respectively). Information on participants’ caffeine intake over recent weeks (the 8 weeks preceding testing) was recorded during the week preceding testing using a caffeine intake questionnaire that assessed the frequency of consumption of teas, coffees, colas, other caffeine-containing drinks (e.g. Red Bull) and products (e.g. Pro-Plus), and chocolate. Change from baseline data were calculated for self-rated anxiety and mental alertness, and (systolic and diastolic) blood pressure, by subtracting the baseline data from the post-treatment data. These data were analyzed for effects of caffeine using paired t- tests (caffeine vs placebo). Effects of caffeine (caffeine vs placebo) and threat (angry/fearful faces vs happy faces) on face-matching accuracy (percentage correct) and reaction time (ms) were also assessed with paired t- tests.
  • Comments Comments (
    0
    ) |
What conflicts of interest were reported? The authors declare that over the past 3 years J.E.S. has received a PhD maintenance grant from Unilever Research and Development Vlaardingen, the Netherlands. P.J.R. has received consulting fees from Unilever; and grants for research from Cadbury, DSM, GSK and Unilever.
  • Comments Comments (
    0
    ) |
Refid 21972425
  • Comments Comments (
    0
    ) |
What were the sources of funding? Support for this study was provided by grants from the University of Bristol’s Faculty of Science, a Career Development Award from the Medical Research Council UK (to R.G.W) and The Wales Institute of Cognitive Neuroscience (to A.D.L.)
  • Comments Comments (
    0
    ) |




Results & Comparisons

No Results found.