Working Memory Performance after Daily Caffeine Intake: Compromised Performance and Reduced Hippocampal Activity.

Neuroprotective effects of caffeine have been frequently reported in the context of disease and cognitive dysfunction as well as in epidemiological studies in humans. However, evidence on caffeine effects on neural and memory functions during daily intake in a healthy cognitive state remains scarce. This randomized double-blind placebo-controlled crossover study investigated working memory functions by N-back tasks and functional magnetic resonance imaging (fMRI) after daily caffeine intake compared to a placebo baseline and to acute caffeine withdrawal in 20 young healthy volunteers. Each volunteer was given 3 times 150 mg caffeine for 10 days in the daily caffeine condition, 3 times 150 mg mannitol for 10 days in the placebo condition, and 9-day caffeine plus 1-day mannitol in the acute withdrawal condition. During the 10th day, participants performed 4 N-back sessions (two loads each: 0- and 3-back) under controlled laboratory conditions. During the 4th session of N-Back (i.e. at 5.5 h, 36.5 h and > 10 days after the last caffeine intake in the caffeine, withdrawal, and placebo condition, respectively) we assessed blood-oxygen-level-dependent (BOLD) activity. During the entire 10th day, in 0-back tasks, we observed longer reaction times (RTs) in the withdrawal compared to the placebo (Cohens d = 0.7) and caffeine condition (Cohens d = 0.6), but no significant effects of conditions on error rates. In contrast, in 3-back tasks (controlled for 0-back), the RTs in the caffeine condition were longer compared to placebo (Cohens d = 0.6) and withdrawal (Cohens d = 0.5). Error rates were higher during both caffeine and withdrawal conditions compared to placebo (Cohens d of both contrasts = 0.4). Whole-brain analyses on fMRI data did not reveal significant condition-dependent differences in activities between task loads. Across task loads, however, we observed a reduced hippocampal activation (Cohens d = -1.3) during the caffeine condition compared to placebo, while no significant difference in brain activities between withdrawal and placebo conditions. Taken together, the worse working memory function and the hippocampal hypoactivation implicate a potential detrimental effect of daily caffeine intake on neurocognitive functions of healthy adults. Moreover, they echo the hippocampal volumetric reduction reported previously in the same volunteers. Lastly, acute withdrawal from daily caffeine intake impairs both low-order cognitive processes and working memory performance. Taking earlier studies on acute caffeine effects into account, our findings indicate that daily caffeine intake elicits a dynamic change in cerebral activities during the course of repeated consumption, with unknown consequences in the long run.

Use of therapeutic caffeine in acute care postoperative and critical care settings: a scoping review

Background Caffeine is the most utilised psychoactive drug worldwide. However, caffeine withdrawal and the therapeutic use of caffeine in intensive care and in the perioperative period have not been well summarised. Our objective was to conduct a scoping review of caffeine withdrawal and use in the intensive care unit (ICU) and postoperative patients. Methods PubMed, Embase, CINAHL Complete, Scopus and Web of Science were systematically searched for studies investigating the effects of caffeine withdrawal or administration in ICU patients and in the perioperative period. Areas of recent systematic review such as pain or post-dural puncture headache were not included in this review. Studies were limited to adults. Results Of 2268 articles screened, 26 were included and grouped into two themes of caffeine use in in the perioperative period and in the ICU. Caffeine withdrawal in the postoperative period increases the incidence of headache, which can be effectively treated prophylactically with perioperative caffeine. There were no studies investigating caffeine withdrawal or effect on sleep wake cycles, daytime somnolence, or delirium in the intensive care setting. Administration of caffeine results in faster emergence from sedation and anaesthesia, particularly in individuals who are at high risk of post-extubation complications. There has only been one study investigating caffeine administration to facilitate post-anaesthetic emergence in ICU. Caffeine administration appears to be safe in moderate doses in the perioperative period and in the intensive care setting. Conclusions Although caffeine is widely used, there is a paucity of studies investigating withdrawal or therapeutic effects in patients admitted to ICU and further novel studies are a priority.

Review Effect of Caffeine Overdose

Background: Caffeine is from methyl xanthine class which mainly stimulates the central nervous system. Caffeine is one of the most widely used psychoactive drugs in the world. It is commonly found in beverages, chocolates, cocoa containing products and in medications. Caffeine is recognized as legal and its consumption is unregulated all over of the world. Objectives: The objective of this study is to summarize the impact of caffeine on behavioral and health alterations, in both controlled and overdose conditions. Moreover, the specifics of caffeine withdrawal and a number of guidelines on how to handle reducing or quitting caffeine intake altogether is also highlighted. Methodology: To compose this review, more than seventy research and review articles were overviewed that were published over a period of last twenty years, using Google Scholar search engines. Results: Caffeine regular use causes physical dependence which may become the caffeine withdrawal sign that can consequently harm normal working. The most important function of caffeine is that it can reversibly blocks the adenosine performance on its receptor and as a result which prevent the beginning of drowsiness encouraged by adenosine. Caffeine also stimulates certain portions of the autonomic nervous system symptom including fatigue, drowsiness, depressed mood, headache, difficulty concentrating, decreased energy, decreased contentedness, decreased alertness, irritability and unclear headed. Conclusion: It is concluded that utilization of caffeine in a prescribed dose can have good impact on health and may decrease addictive symptoms. Additionally, reducing caffeine dosage over a six week period guides to successful, long-term caffeine cessation with very few side effects.

Traditional Persian Medicine Suggestions to Prevent Fasting Headache

Headache is one of the most common medical problems experienced by the majority of general population. In the latest version of the International Classification of Headache Disorders (ICHD-III) beta in 2013, fasting headache, has been classified as a secondary headache, and a subheading of “Headache attributed to fasting”. Suggested controversial hypothesis of this medical condition include associations with hypoglycemia, sleep quality and caffeine withdrawal, although these relationships have not been confirmed yet. The principal purpose of the present study is to review the etiology and proposed preventive and treating strategies regarding fasting headache in Persian Medicine (PM) literature. This complaint is regarded as a headache associated with dryness in PM. Therefore, words related to "dryness" from PM references. Relevant keywords were also searched in modern medical literature and PubMed, Scopus, Google scholar, Web of science and Sid databases. Obtained results were subsequently compared following classification. Fasting plays a causative role in increasing heat in the heart, liver, and stomach (and other organs), and also decreasing body moisture. Therefore, the effective management as proposed by PM is reducing the heat and increasing body moisture. More research is needed to provide academic evidence in this regard.

Use of Therapeutic Caffeine in Acute Care Post-operative and Critical Care Settings: a Scoping Review

BackgroundCaffeine is the most utilised psychoactive drug worldwide. However, caffeine withdrawal and the therapeutic use of caffeine in intensive care and in the peri-operative period have not been well summarised. Our objective was to conduct a scoping review of caffeine withdrawal and use in the intensive care unit (ICU) and post-operative patients. MethodsPubMed, Embase, CINAHL Complete, Scopus and Web of Science were systematically searched for studies investigating the effects of caffeine withdrawal or administration in ICU patients and in the peri-operative period. Areas of recent systematic review such as pain or post-dural puncture headache were not included in this review. Studies were limited to adults. ResultsOf 2268 articles screened, 26 were included and grouped into two themes of caffeine use in in the peri-operative period and in the ICU. Caffeine withdrawal in the post-operative period increases the incidence of headache, which can be effectively treated prophylactically with peri-operative caffeine. There were no studies investigating caffeine withdrawal or effect on sleep wake cycles, daytime somnolence, or delirium in the intensive care setting. Administration of caffeine results in faster emergence from sedation and anaesthesia, particularly in individuals who are at high risk of post-extubation complications. There has only been one study investigating caffeine administration to facilitate post-anaesthetic emergence in ICU. Caffeine administration appears to be safe in moderate doses in the peri-operative period and in the intensive care setting. ConclusionsAlthough caffeine is widely used, there is a paucity of studies investigating withdrawal or therapeutic effects in patients admitted to ICU and further novel studies are a priority.

Caffeine Consumption & Perception of Its Effects Amongst University Students

Introduction: A variety of research studies have shown that caffeine usage is highly prevalent among university students and many of them have different perception of its effect on their mental and physical health. These perceptions can influence the intake of caffeine which may lead to its addiction, resulting in serious public health consequences. Aims & Objectives: The objective of the study is to determine the frequency of caffeine consumption and the perception of its effects among university students. Place and duration of study: This study was conducted within 6 months duration, from May 2018 to October 2019 among students of three private universities in Lahore, Pakistan. Material & Methods: This was a descriptive cross-sectional study. A sample size of 670 university students was taken and the data were collected from three private universities of Lahore through convenience sampling technique. The perception of effects of caffeine was determined through a pre-validated questionnaire, Caffeine Expectancy Questionnaire (CaffEQ) from consumers and nonconsumers of caffeine. Results: A total of 670 university students participated in the study, out of which, 278 (41.5%) were males and 392 (58.5%) were females. 506 (75.5%) participants were consumer of caffeine, while 164 (24.5%) were non consumer. The occurrence of caffeine consumption was more in males (79.9%) than in females (72.4%). Participants reported that they consume caffeine because it makes them feel more alert (83.4%), they experience caffeine withdrawal without caffeine (83%) and caffeine makes them feel more energetic (80.6%). The perceptions due to which participants don't consume caffeine were that they expect caffeine makes their heartbeat irregular (81.7%), they don't like the way caffeine makes them feel (80.5%) and caffeine makes them irritable (76.8%). Conclusion: The study concludes that male students had more tendencies towards caffeine consumption than females. Perceptions for consuming caffeine were feeling of alertness, experiencing caffeine withdrawal symptoms, feeling of energy and ability to work over long periods of time after having caffeine. The perceptions for not consuming caffeine were irregular heartbeat, bad feelings, irritability, and sleep disturbances.