-
1.
Stimulant Drugs of Abuse and Cardiac Arrhythmias.
Dominic, P, Ahmad, J, Awwab, H, Bhuiyan, MS, Kevil, CG, Goeders, NE, Murnane, KS, Patterson, JC, Sandau, KE, Gopinathannair, R, et al
Circulation. Arrhythmia and electrophysiology. 2022;(1):e010273
-
-
Free full text
-
Abstract
Nonmedical use of prescription and nonprescription drugs is a worldwide epidemic, rapidly growing in magnitude with deaths because of overdose and chronic use. A vast majority of these drugs are stimulants that have various effects on the cardiovascular system including the cardiac rhythm. Drugs, like cocaine and methamphetamine, have measured effects on the conduction system and through several direct and indirect pathways, utilizing multiple second messenger systems, change the structural and electrical substrate of the heart, thereby promoting cardiac dysrhythmias. Substituted amphetamines and cocaine affect the expression and activation kinetics of multiple ion channels and calcium signaling proteins resulting in EKG changes, and atrial and ventricular brady and tachyarrhythmias. Preexisting conditions cause substrate changes in the heart, which decrease the threshold for such drug-induced cardiac arrhythmias. The treatment of cardiac arrhythmias in patients who take drugs of abuse may be specialized and will require an understanding of the unique underlying mechanisms and necessitates a multidisciplinary approach. The use of primary or secondary prevention defibrillators in drug abusers with chronic systolic heart failure is both sensitive and controversial. This review provides a broad overview of cardiac arrhythmias associated with stimulant substance abuse and their management.
-
2.
Idiopathic Hypersomnia and Other Hypersomnia Syndromes.
Trotti, LM, Arnulf, I
Neurotherapeutics : the journal of the American Society for Experimental NeuroTherapeutics. 2021;(1):20-31
-
-
Free full text
-
Abstract
There are numerous disorders of known or presumed neurologic origin that result in excessive daytime sleepiness, collectively known as the central disorders of hypersomnolence. These include narcolepsy types 1 and 2, idiopathic hypersomnia, Kleine-Levin syndrome, and hypersomnia due to or associated with medical disease, neurologic disease, psychiatric disease, medications or substances, and insufficient sleep durations. This chapter focuses on the treatment of nonnarcoleptic hypersomnia syndromes, from those that are commonly encountered in neurologic practice, such as hypersomnia due to Parkinson's disease, to those that are exceedingly rare but present with dramatic manifestations, such as Kleine-Levin syndrome. The level of evidence for the treatment of sleepiness in these disorders is generally lower than in the well-characterized syndrome of narcolepsy, but available clinical and randomized, controlled trial data can provide guidance for the management of each of these disorders. Treatments vary by diagnosis but may include modafinil/armodafinil, traditional psychostimulants, solriamfetol, pitolisant, clarithromycin, flumazenil, sodium oxybate, melatonin, methylprednisolone, and lithium.
-
3.
Effect of caffeine on vestibular evoked myogenic potential: a systematic review with meta-analysis.
Souza, MEDCA, Costa, KVTD, Menezes, PL
Brazilian journal of otorhinolaryngology. 2018;(3):381-388
Abstract
INTRODUCTION Caffeine can be considered the most consumed drug by adults worldwide, and can be found in several foods, such as chocolate, coffee, tea, soda and others. Overall, caffeine in moderate doses, results in increased physical and intellectual productivity, increases the capacity of concentration and reduces the time of reaction to sensory stimuli. On the other hand, high doses can cause noticeable signs of mental confusion and error induction in intellectual tasks, anxiety, restlessness, muscle tremors, tachycardia, labyrinthine changes, and tinnitus. OBJECTIVE Considering that the vestibular evoked myogenic potential is a clinical test that evaluates the muscular response of high intensity auditory stimulation, the present systematic review aimed to analyze the effects of caffeine on vestibular evoked myogenic potential. METHODS This study consisted of the search of the following databases: MEDLINE, CENTRAL, ScienceDirect, Scopus, Web of Science, LILACS, SciELO and ClinicalTrials.gov. Additionally, the gray literature was also searched. The search strategy included terms related to intervention (caffeine or coffee consumption) and the primary outcome (vestibular evoked myogenic potential). RESULTS Based on the 253 potentially relevant articles identified through the database search, only two full-text publications were retrieved for further evaluation, which were maintained for qualitative analysis. CONCLUSION Analyzing the articles found, caffeine has no effect on vestibular evoked myogenic potential in normal individuals.
-
4.
The Role of Genetics in Moderating the Inter-Individual Differences in the Ergogenicity of Caffeine.
Southward, K, Rutherfurd-Markwick, K, Badenhorst, C, Ali, A
Nutrients. 2018;(10)
Abstract
Caffeine use is widespread among athletes following its removal from the World Anti-Doping Agency banned list, with approximately 75% of competitive athletes using caffeine. While literature supports that caffeine has a small positive ergogenic effect for most forms of sports and exercise, there exists a significant amount of inter-individual difference in the response to caffeine ingestion and the subsequent effect on exercise performance. In this narrative review, we discuss some of the potential mechanisms and focus on the role that genetics has in these differences. CYP1A2 and ADORA2A are two of the genes which are thought to have the largest impact on the ergogenicity of caffeine. CYP1A2 is responsible for the majority of the metabolism of caffeine, and ADORA2A has been linked to caffeine-induced anxiety. The effects of CYP1A2 and ADORA2A genes on responses to caffeine will be discussed in detail and an overview of the current literature will be presented. The role of these two genes may explain a large portion of the inter-individual variance reported by studies following caffeine ingestion. Elucidating the extent to which these genes moderate responses to caffeine during exercise will ensure caffeine supplementation programs can be tailored to individual athletes in order to maximize the potential ergogenic effect.
-
5.
Mendelian Randomization Studies of Coffee and Caffeine Consumption.
Cornelis, MC, Munafo, MR
Nutrients. 2018;(10)
Abstract
Habitual coffee and caffeine consumption has been reported to be associated with numerous health outcomes. This perspective focuses on Mendelian Randomization (MR) approaches for determining whether such associations are causal. Genetic instruments for coffee and caffeine consumption are described, along with key concepts of MR and particular challenges when applying this approach to studies of coffee and caffeine. To date, at least fifteen MR studies have investigated the causal role of coffee or caffeine use on risk of type 2 diabetes, cardiovascular disease, Alzheimer's disease, Parkinson's disease, gout, osteoarthritis, cancers, sleep disturbances and other substance use. Most studies provide no consistent support for a causal role of coffee or caffeine on these health outcomes. Common study limitations include low statistical power, potential pleiotropy, and risk of collider bias. As a result, in many cases a causal role cannot confidently be ruled out. Conceptual challenges also arise from the different aspects of coffee and caffeine use captured by current genetic instruments. Nevertheless, with continued genome-wide searches for coffee and caffeine related loci along with advanced statistical methods and MR designs, MR promises to be a valuable approach to understanding the causal impact that coffee and caffeine have in human health.
-
6.
Administration of Caffeine in Alternate Forms.
Wickham, KA, Spriet, LL
Sports medicine (Auckland, N.Z.). 2018;(Suppl 1):79-91
-
-
Free full text
-
Abstract
There has been recent interest in the ergogenic effects of caffeine delivered in low doses (~ 200 mg or ~ 3 mg/kg body mass) and administered in forms other than capsules, coffee and sports drinks, including chewing gum, bars, gels, mouth rinses, energy drinks and aerosols. Caffeinated chewing gum is absorbed quicker through the buccal mucosa compared with capsule delivery and absorption in the gut, although total caffeine absorption over time is not different. Rapid absorption may be important in many sporting situations. Caffeinated chewing gum improved endurance cycling performance, and there is limited evidence that repeated sprint cycling and power production may also be improved. Mouth rinsing with caffeine may stimulate nerves with direct links to the brain, in addition to caffeine absorption in the mouth. However, caffeine mouth rinsing has not been shown to have significant effects on cognitive performance. Delivering caffeine with mouth rinsing improved short-duration, high-intensity, repeated sprinting in normal and depleted glycogen states, while the majority of the literature indicates no ergogenic effect on aerobic exercise performance, and resistance exercise has not been adequately studied. Studies with caffeinated energy drinks have generally not examined the individual effects of caffeine on performance, making conclusions about this form of caffeine delivery impossible. Caffeinated aerosol mouth and nasal sprays may stimulate nerves with direct brain connections and enter the blood via mucosal and pulmonary absorption, although little support exists for caffeine delivered in this manner. Overall, more research is needed examining alternate forms of caffeine delivery including direct measures of brain activation and entry of caffeine into the blood, as well as more studies examining trained athletes and female subjects.
-
7.
The Influence of Caffeine Expectancies on Sport, Exercise, and Cognitive Performance.
Shabir, A, Hooton, A, Tallis, J, F Higgins, M
Nutrients. 2018;(10)
Abstract
Caffeine (CAF) is widely consumed across sport and exercise for its reputed ergogenic properties, including central nervous stimulation and enhanced muscular force development. However, expectancy and the related psychological permutations that are associated with oral CAF ingestion are generally not considered in most experimental designs and these could be important in understanding if/how CAF elicits an ergogenic effect. The present paper reviews 17 intervention studies across sport, exercise, and cognitive performance. All explore CAF expectancies, in conjunction with/without CAF pharmacology. Thirteen out of 17 studies indicated expectancy effects of varying magnitudes across a range of exercise tasks and cognitive skills inclusive off but not limited to; endurance capacity, weightlifting performance, simple reaction time and memory. Factors, such as motivation, belief, and habitual CAF consumption habits influenced the response. In many instances, these effects were comparable to CAF pharmacology. Given these findings and the lack of consistency in the experimental design, future research acknowledging factors, such as habitual CAF consumption habits, habituated expectations, and the importance of subjective post-hoc analysis will help to advance knowledge within this area.
-
8.
Caffeine and headache: specific remarks.
Espinosa Jovel, CA, Sobrino Mejía, FE
Neurologia (Barcelona, Spain). 2017;(6):394-398
Abstract
Caffeine is the most widely used psychostimulant worldwide. Excessive caffeine consumption induces a series of both acute and chronic biological and physiological changes that may give rise to cognitive decline, depression, fatigue, insomnia, cardiovascular changes, and headache. Chronic consumption of caffeine promotes a pro-nociceptive state of cortical hyperexcitability that can intensify a primary headache or trigger a headache due to excessive analgesic use. This review offers an in-depth analysis of the physiological mechanisms of caffeine and its relationship with headache.
-
9.
Aneurysmal subarachnoid hemorrhage and severe, catheter-induced vasospasm associated with excessive consumption of a caffeinated energy drink.
Grant, RA, Cord, BJ, Kuzomunhu, L, Sheth, K, Gilmore, E, Matouk, CC
Interventional neuroradiology : journal of peritherapeutic neuroradiology, surgical procedures and related neurosciences. 2016;(6):674-678
-
-
Free full text
-
Abstract
Excessive consumption of over-the-counter stimulants is associated with coronary vasospasm, thrombotic complications, and sudden cardiac death. Their effects on cerebrovascular physiology are not yet described in the neurointerventional literature. Patients are increasingly exposed to high levels of these vasoactive substances in the form of caffeinated energy drinks and specialty coffees. We report a case of aneurysmal subarachnoid hemorrhage (SAH) and severe, catheter-induced vasospasm during attempted endovascular repair of a ruptured anterior communicating artery (AComA) aneurysm in the setting of excessive energy drink consumption. We review the literature and alert clinicians to this potentially serious complication.
-
10.
The Role of Caffeine in Noninvasive Respiratory Support.
Dobson, NR, Patel, RM
Clinics in perinatology. 2016;(4):773-782
-
-
Free full text
-
Abstract
Caffeine is one of the most commonly prescribed medications in preterm neonates and is widely used to treat or prevent apnea of prematurity. Caffeine therapy is safe, effectively decreases apnea, and improves short- and long-term outcomes in preterm infants. In this review, the authors summarize the role of caffeine therapy for preterm infants receiving noninvasive respiratory support. As caffeine is already widely used, recent data are summarized that may guide clinicians in optimizing the use of caffeine therapy, with a review of the timing of initiation, dose, and duration of therapy.