Caffeine and headaches

Effects of caffeine on intracranial pressure and pain perception in freely moving rats

OBJECTIVE

Caffeine, a non-selective adenosine receptor (AR) antagonist, is the most consumed psychostimulant in the world. Caffeine has been suggested to regulate cerebrospinal fluid secretion and is known both to alleviate and to trigger headache; however, its effect on the regulation of intracranial pressure (ICP) is not known. Therefore, we aimed to investigate the effects of caffeine on ICP and nociceptive responses.

METHODS

Female Sprague-Dawley rats were implanted with a novel telemetric device for continuous ICP recordings, which allowed for continuous recordings in freely moving rats. A single dose of caffeine (30 or 120 mg/kg intraperitoneally) was given. In a second group (non-implanted), the acute effects of 30 mg/kg caffeine on periorbital threshold using Von Frey testing and spontaneous behavior were utilized using an automated behavioral registration platform (Laboratory, Animal, Behavior, Observation, Registration and Analysis System) in a randomized cross-over study. Quantitative polymerase chain reaction and immunofluorescence were used to localize ARs in the choroid plexus.

RESULTS

A single dose of 30 mg/kg caffeine lowered the ICP by 35% at 165 min after administration (saline: 0.16 ± 0.9 vs caffeine: -1.18 ± 0.9 ΔmmHg, p = 0.0098) and lasted up to 12 h. Administration of 120 mg/kg caffeine showed a faster onset of decrease in ICP within 15 min by 50% (p = 0.0018) and lasted up to 12 h. The periorbital pain thresholds were higher after 1 h (saline: 224.6 ± 15.1 vs caffeine: 289.5 ± 8.7 g, p = 0.005) and lasted up to 5 h. Caffeine-treated rats had increased locomotor activity, speed, and changed grooming behavior. Expression of AR1 was found in the choroid plexus.

CONCLUSIONS

This study demonstrates that caffeine has a lowering effect on ICP as an acute treatment. Interestingly, caffeine acutely caused an increased response in cephalic thresholds supporting hypoalgesic effects. Future studies investigating the beneficial effects of caffeine for elevated ICP are warranted.

All Roads Lead to the Gut: The Importance of the Microbiota and Diet in Migraine

Migraine, a prevalent neurological condition and the third most common disease globally, places a significant economic burden on society. Despite extensive research efforts, the precise underlying mechanism of the disease remains incompletely comprehended. Nevertheless, it is established that the activation and sensitization of the trigeminal system are crucial during migraine attacks, and specific substances have been recognized for their distinct involvement in the pathomechanism of migraine. Recently, an expanding body of data indicates that migraine attacks can be prevented and treated through dietary means. It is important to highlight that the various diets available pose risks for patients without professional guidance. This comprehensive overview explores the connection between migraine, the gut microbiome, and gastrointestinal disorders. It provides insight into migraine-triggering foods, and discusses potential diets to help reduce the frequency and severity of migraine attacks. Additionally, it delves into the benefits of using pre- and probiotics as adjunctive therapy in migraine treatment.

Synergistic Effects of Caffeine in Combination with Conventional Drugs: Perspectives of a Drug That Never Ages

Plants have been known since ancient times for their healing properties, being used as preparations against human diseases of different etiologies. More recently, natural products have been studied and characterized, isolating the phytochemicals responsible for their bioactivity. Most certainly, there are currently numerous active compounds extracted from plants and used as drugs, dietary supplements, or sources of bioactive molecules that are useful in modern drug discovery. Furthermore, phytotherapeutics can modulate the clinical effects of co-administered conventional drugs. In the last few decades, the interest has increased even more in studying the positive synergistic effects between plant-derived bioactives and conventional drugs. Indeed, synergism is a process where multiple compounds act together to exert a merged effect that is greater than that of each of them summed together. The synergistic effects between phytotherapeutics and conventional drugs have been described in different therapeutic areas, and many drugs are based on synergistic interactions with plant derivatives. Among them, caffeine has shown positive synergistic effects with different conventional drugs. Indeed, in addition to their multiple pharmacological activities, a growing body of evidence highlights the synergistic effects of caffeine with different conventional drugs in various therapeutic fields. This review aims to provide an overview of the synergistic therapeutic effects of caffeine and conventional drugs, summarizing the progress reported to date.

Neuroepidemiology study of headache in the region of Jammu of north Indian population: A cross-sectional study

Background

Headache disorders now represent a major public health problem globally. It is more prevalent in developing countries with the rising trends of headache disorders observed in young adults affecting their quality of life negatively. Very little information is available on the epidemiology of headache disorders in the Jammu Division of the north Indian population.

Aim

The aim of the present study was to find out the prevalence of headache and its two major types, i.e., migraine and tension-type headache (TTH), in the population of the Jammu Division.

Methods

The present study was conducted in two phases: (Phase I: face-to-face interview and Phase II: E-based sampling) and the sufferers of headaches were incorporated into the study based on the International Classification of Headache Disorder-3 (ICHD-3) criteria for a representative sample. Frequency distribution and mean ± standard deviation were used in descriptive statistics to describe the data sets, while a t-test, chi-square test, multiple logistic regression, and prevalence ratio were used in inferential statistics.

Results

In the present study, a total of 3,148 patients were recruited, with an overall prevalence of headache of 53.84%, with a majority of females (38.18%) over males (15.66%). As regards the type of headache, migraine was found to be of the more prevalent (33.25%) type than the TTH (20.58%). Females suffering from migraine showed the highest prevalence (25.28%), in contrast to females suffering from the TTH (12.89%). Sociodemographic variables, such as gender [female; AOR = 2.46, 95% CI (2.12-2.85), p-value < 0.0001] and marital status [married; AOR: 1.46, 95% CI (1.11-1.92) p-value = 0.006], showed a significant association with the headache.

Conclusion

The present study shows that the prevalence of headache is high in the Jammu Division of Jammu and Kashmir (J&K) India, with migraine being the highly prevalent type.

Coadministration of ibuprofen/caffeine on bleaching-induced tooth sensitivity: A randomized clinical trial

This clinical trial evaluated the effect of the coadministration of ibuprofen/caffeine on bleaching-induced tooth sensitivity (TS). A triple-blind, parallel-design, randomized clinical trial was conducted on 84 patients who received ibuprofen/caffeine or placebo capsules. The drugs were administered for 48 hours, starting 1 hour before the in-office bleaching. Two bleaching sessions were performed with 35% hydrogen peroxide gel with 1-week interval. TS was recorded up to 48 hours after dental bleaching with a 0-10 visual analogic scale (VAS) and a 5-point numeric rating scale (NRS). The color was evaluated with VITA Classical and VITA Bleachedguide scales (ΔSGU) and VITA Easyshade spectrophotometer (ΔE*ab and ΔE00). The absolute risk of TS in both groups was evaluated using Fischer's exact test. Comparisons of the TS intensity (NRS and VAS data) were performed by using the Mann-Whitney test and a two-way repeated measures ANOVA, respectively. The color alteration between the groups was compared with the Student's t test. The significance level was 5%. There was no statistically significant difference between the groups for the absolute risk of TS (p = 1.00) or for the intensity of TS (p > 0.05). A bleaching of approximately 7 shade guide units was observed on the Vita Classical and Vita Bleachedguide scales, with no statistical difference between the groups. It was concluded that coadministration of ibuprofen and caffeine did not reduce the absolute risk or intensity of TS and did not interfere with the efficacy of dental bleaching.

The Medicinal Chemistry of Caffeine

The purine alkaloid caffeine is the most widely consumed psychostimulant drug in the world and has multiple beneficial pharmacological activities, for example, in neurodegenerative diseases. However, despite being an extensively studied bioactive natural product, the mechanistic understanding of caffeine's pharmacological effects is incomplete. While several molecular targets of caffeine such as adenosine receptors and phosphodiesterases have been known for decades and inspired numerous medicinal chemistry programs, new protein interactions of the xanthine are continuously discovered providing potentially improved pharmacological understanding and a molecular basis for future medicinal chemistry. In this Perspective, we gather knowledge on the confirmed protein interactions, structure activity relationship, and chemical biology of caffeine on well-known and upcoming targets. The diversity of caffeine's molecular activities on receptors and enzymes, many of which are abundant in the CNS, indicates a complex interplay of several mechanisms contributing to neuroprotective effects and highlights new targets as attractive subjects for drug discovery.

Caffeine and Primary (Migraine) Headaches-Friend or Foe?

Background: The actions of caffeine as an antagonist of adenosine receptors have been extensively studied, and there is no doubt that both daily and sporadic dietary consumption of caffeine has substantial biological effects on the nervous system. Caffeine influences headaches, the migraine syndrome in particular, but how is unclear. Materials and Methods: This is a narrative review based on selected articles from an extensive literature search. The aim of this study is to elucidate and discuss how caffeine may affect the migraine syndrome and discuss the potential pathophysiological pathways involved. Results: Whether caffeine has any significant analgesic and/or prophylactic effect in migraine remains elusive. Neither is it clear whether caffeine withdrawal is an important trigger for migraine. However, withdrawal after chronic exposure of caffeine may cause migraine-like headache and a syndrome similar to that experienced in the prodromal phase of migraine. Sensory hypersensitivity however, does not seem to be a part of the caffeine withdrawal syndrome. Whether it is among migraineurs is unknown. From a modern viewpoint, the traditional vascular explanation of the withdrawal headache is too simplistic and partly not conceivable. Peripheral mechanisms can hardly explain prodromal symptoms and non-headache withdrawal symptoms. Several lines of evidence point at the hypothalamus as a locus where pivotal actions take place. Conclusion: In general, chronic consumption of caffeine seems to increase the burden of migraine, but a protective effect as an acute treatment or in severely affected patients cannot be excluded. Future clinical trials should explore the relationship between caffeine withdrawal and migraine, and investigate the effects of long-term elimination.

Headache in the elderly

Headache is the most common neurologic symptom and affects nearly half the world's population at any given time. Although the prevalence declines with age, headache remains a common neurologic complaint among elderly populations. Headaches can be divided into primary and secondary causes. Primary headaches comprise about two-thirds of headaches among the elderly. They are defined by clinical criteria and are diagnosed based on symptom pattern and exclusion of secondary causes. Primary headaches include migraine, tension-type, trigeminal autonomic cephalalgias, and hypnic headache. Secondary headaches are defined by their suspected etiology. A higher index of suspicion for a secondary headache disorder is warranted in older patients with new-onset headache. They are roughly 12 times more likely to have serious underlying causes and, frequently, have different symptomatic presentations compared to younger adults. Various imaging and laboratory evaluations are indicated in the presence of any "red flag" signs or symptoms. Head CT is the procedure of choice for acute headache presentations, and brain MRI for those with chronic headache complaints. Management of headache in elderly populations can be challenging due to the presence of multiple medical comorbidities, polypharmacy, and differences in drug metabolism and clearance.

A Multicenter Phase II Study of AMG 337 in Patients with MET-Amplified Gastric/Gastroesophageal Junction/Esophageal Adenocarcinoma and Other MET-Amplified Solid Tumors

PURPOSE

MET gene amplification is associated with poor prognosis in gastric/gastroesophageal junction/esophageal (G/GEJ/E) cancers. We determined antitumor activity, safety, and pharmacokinetics of the small-molecule MET inhibitor AMG 337 in MET-amplified G/GEJ/E adenocarcinoma or other solid tumors.Patients and Methods: In this phase II, single-arm study, adults with MET-amplified G/GEJ/E adenocarcinoma (cohort 1) or other MET-amplified solid tumors (cohort 2) received AMG 337 300 mg/day orally in 28-day cycles. The primary endpoint was objective response rate (ORR; cohort 1). Secondary endpoints included ORR (cohort 2), progression-free survival (PFS), overall survival (OS), and safety.

RESULTS

Of 2101 patients screened for MET amplification, 132 were MET-amplified and 60 were enrolled: 45 in cohort 1, and 15 in cohort 2. Fifty-six patients (97%) had metastatic disease; 57 had prior lines of therapy (1 prior line, 29%; ≥2 prior lines, 69%). A protocol-permitted review showed efficacy that was lower-than-expected based on preliminary data from a first-in-human study, and enrollment was stopped. Fifty-eight patients received ≥1 AMG 337 dose. ORR in cohort 1 was 18% (8 partial responses). No responses were observed in cohort 2. Of 54 evaluable patients, median (95% CI) PFS and OS were 3.4 (2.2-5.0) and 7.9 (4.8-10.9) months, respectively. The most frequent adverse events (AEs) were headache (60%), nausea (38%), vomiting (38%), and abdominal pain, decreased appetite, and peripheral edema (33% each); 71% had grade ≥3 AEs and 59% had serious AEs.

CONCLUSIONS

AMG 337 showed antitumor activity in MET-amplified G/GEJ/E adenocarcinoma but not in MET-amplified non-small-cell lung cancer.See related commentary by Ma, p. 2375.

Diagnosis and Treatment of Primary Headache Disorders in Older Adults

OBJECTIVES

To provide a unique perspective on geriatric headache and a number of novel treatment options that are not well known outside of the headache literature.

DESIGN

Review of the most current and relevant headache literature for practitioners specializing in geriatric care.

RESULTS

Evaluation and management of headache disorders in older adults requires an understanding of the underlying pathophysiology and how it relates to age-related physiological changes. To treat headache disorders in general, the appropriate diagnosis must first be established, and treatment of headaches in elderly adults poses unique challenges, including potential polypharmacy, medical comorbidities, and physiological changes associated with aging.

CONCLUSION

The purpose of this review is to provide a guide to and perspective on the challenges inherent in treating headaches in older adults. J Am Geriatr Soc 66:2408-2416, 2018.

Caffeine in the management of patients with headache

Caffeinated headache medications, either alone or in combination with other treatments, are widely used by patients with headache. Clinicians should be familiar with their use as well as the chemistry, pharmacology, dietary and medical sources, clinical benefits, and potential safety issues of caffeine. In this review, we consider the role of caffeine in the over-the-counter treatment of headache. The MEDLINE and Cochrane databases were searched by combining “caffeine” with the terms “headache,” “migraine,” and “tension-type.” Studies that were not placebo-controlled or that involved medications available only with a prescription, as well as those not assessing patients with migraine and/or tension-type headache (TTH), were excluded. Compared with analgesic medication alone, combinations of caffeine with analgesic medications, including acetaminophen, acetylsalicylic acid, and ibuprofen, showed significantly improved efficacy in the treatment of patients with TTH or migraine, with favorable tolerability in the vast majority of patients. The most common adverse events were nervousness (6.5%), nausea (4.3%), abdominal pain/discomfort (4.1%), and dizziness (3.2%). This review provides evidence for the role of caffeine as an analgesic adjuvant in the acute treatment of primary headache with over-the-counter drugs, caffeine doses of 130 mg enhance the efficacy of analgesics in TTH and doses of ≥100 mg enhance benefits in migraine. Additional studies are needed to assess the relationship between caffeine dosing and clinical benefits in patients with TTH and migraine.

Headaches: a Review of the Role of Dietary Factors

Dietary triggers are commonly reported by patients with a variety of headaches, particularly those with migraines. The presence of any specific dietary trigger in migraine patients varies from 10 to 64 % depending on study population and methodology. Some foods trigger headache within an hour while others develop within 12 h post ingestion. Alcohol (especially red wine and beer), chocolate, caffeine, dairy products such as aged cheese, food preservatives with nitrates and nitrites, monosodium glutamate (MSG), and artificial sweeteners such as aspartame have all been studied as migraine triggers in the past. This review focuses the evidence linking these compounds to headache and examines the prevalence of these triggers from prior population-based studies. Recent literature surrounding headache related to fasting and weight loss as well as elimination diets based on serum food antibody testing will also be summarized to help physicians recommend low-risk, non-pharmacological adjunctive therapies for patients with debilitating headaches.

Effect of exclusion of frequently consumed dietary triggers in a cohort of children with chronic primary headache

BACKGROUND

Although dietary factors are known to trigger headaches, the relationship between food and headache in children remains unclear. This prospective, observational case series aimed to evaluate the effect of exclusion of frequently-consumed foods in a cohort of children with headache.

METHODS

One hundred and fifteen children aged 3-15 (mean 10.5) years with primary headache were followed in a paediatric outpatient clinic. Patients who frequently consumed foods or food additives known to trigger headaches were advised to exclude them for six weeks and to return for follow-up with headache and food diary.

RESULTS

One hundred patients attended follow-up. Of these 13 (13%) did not respond to dietary exclusion; 87 (87%) achieved complete resolution of headaches by exclusion of 1-3 of the identified food(s). Caffeine was the most common implicated trigger (28), followed by monosodium glutamate (25), cocoa (22), aspartame (13), cheese (13), citrus (10) and nitrites (six). One patient was sensitive to tomatoes.

CONCLUSIONS

This study demonstrates the potential scale and significance of seven frequently consumed foods or food additives as triggers for primary headache in children. Also this is the first study to show that headaches can be triggered by the cumulative effect of a food that is frequently consumed, rather than by single time ingestion.

Caffeine: cognitive and physical performance enhancer or psychoactive drug?

Caffeine use is increasing worldwide. The underlying motivations are mainly concentration and memory enhancement and physical performance improvement. Coffee and caffeine-containing products affect the cardiovascular system, with their positive inotropic and chronotropic effects, and the central nervous system, with their locomotor activity stimulation and anxiogenic-like effects. Thus, it is of interest to examine whether these effects could be detrimental for health. Furthermore, caffeine abuse and dependence are becoming more and more common and can lead to caffeine intoxication, which puts individuals at risk for premature and unnatural death. The present review summarizes the main findings concerning caffeine’s mechanisms of action (focusing on adenosine antagonism, intracellular calcium mobilization, and phosphodiesterases inhibition), use, abuse, dependence, intoxication, and lethal effects. It also suggests that the concepts of toxic and lethal doses are relative, since doses below the toxic and/or lethal range may play a causal role in intoxication or death. This could be due to caffeine’s interaction with other substances or to the individuals' preexisting metabolism alterations or diseases.

Medication overuse and chronic migraine: a critical review according to clinical pharmacology

INTRODUCTION

Chronic migraine is often complicated by medication-overuse headache (MOH), a headache due to excessive intake of acute medications. Chronic migraine and MOH are serious and disabling disorders. Since chronic migraine derives from the progression of originally episodic migraine, the fundamental therapeutic strategy is prevention. This narrative review describes how to try to prevent the development of MOH and how to manage it once it has appeared.

AREAS COVERED

A PubMed database search (from 1988 to January 2015) and a review of published studies on chronic migraine and MOH were conducted.

EXPERT OPINION

In spite of progress in migraine treatment, the prevalence of chronic headaches and MOH has not changed in the course of time. Today, a large number of migraine patients have turned to numerous expert physicians and experienced all sorts of prophylactic treatments without decisive benefits. Their condition seems to have crystallized even more as chronic and intractable. This means that to prevent chronification and MOH, we need more effective drugs and better strategies to use them. In particular, we must detect disease biomarkers and predictive factors for drug response that allow for personalized treatment when migraine is still episodic and make analgesic overuse pointless.

Caffeine and headache: specific remarks

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.

Association of psychologic and nonpsychologic factors with primary dysmenorrhea

Background:

Primary dysmenorrhea seems to be one the most common gynecologic condition in women of childbearing age.

Objectives:

The aim of this research was to evaluate psychologic and nonpsychologic risk factors of primary dysmenorrhea.

Materials and Methods:

A cross-sectional study was conducted on medical sciences students of Babol University of Medical Sciences. In this study, 180 females with dysmenorrhea and 180 females without dysmenorrhea were enrolled. Psychological risk factors were evaluated in four domains including affect, social support, personality, and alexithymia. Four questionnaires were used to assessed aforementioned domains, namely, Social Support Questionnaire (SSQ), depression, anxiety, stress (DAS-21), 20-item Toronto Alexithymia Scale (TAS-20), and NEO-Five Factor Inventory of Personality (NEO-FFI). In addition, nonpsychologic factors were evaluated in three domains including demographic characteristics, habits, and gynecologic factors. Data were analyzed using the χ2 test and multiple logistic regression analysis.

Results:

The strongest predictor of primary dysmenorrhea was low social support (OR = 4.25; 95% CI, 2.43-7.41). Risk of dysmenorrhea was approximately 3.3 times higher in women with alexithymia (OR = 3.26; 95% CI, 1.88-5.62), 3.1 times higher in women with menstrual bleeding duration ≥ 7 days (OR = 3.06; 95% CI, 1.73-5.41), 2.5 times higher in women with a neurotic character (OR = 2.53; 95% CI, 1.42-4.50), 2.4 times higher in women with a family history of dysmenorrhea (OR = 2.43; 95% CI, 1.42-4.50), and twice higher in women with high caffeine intake (OR = 1.97; 95% CI, 1.09-3.59).

Conclusions:

Low social support, alexithymia, neuroticism trait, long menstrual bleeding, family history of dysmenorrhea, and high-caffeine diet are important risk factors for women with primary dysmenorrhea. This study recommended considering psychologic factors as an adjuvant to medical risks in evaluation and treatment of primary dysmenorrhea.

Headache and sleep: shared pathophysiological mechanisms

OBJECTIVE

The objective of the current article is to review the shared pathophysiological mechanisms which may underlie the clinical association between headaches and sleep disorders.

BACKGROUND

The association between sleep and headache is well documented in terms of clinical phenotypes. Disrupted sleep-wake patterns appear to predispose individuals to headache attacks and increase the risk of chronification, while sleep is one of the longest established abortive strategies. In agreement, narcoleptic patients show an increased prevalence of migraine compared to the general population and specific familial sleep disorders have been identified to be comorbid with migraine with aura.

CONCLUSION

The pathophysiology and pharmacology of headache and sleep disorders involves an array of neural networks which likely underlie their shared clinical association. While it is difficult to differentiate between cause and effect, or simply a spurious relationship the striking brainstem, hypothalamic and thalamic convergence would suggest a bidirectional influence.

The study of interactions between active compounds of coffee and willow (Salix sp.) bark water extract

Coffee and willow are known as valuable sources of biologically active phytochemicals such as chlorogenic acid, caffeine, and salicin. The aim of the study was to determine the interactions between the active compounds contained in water extracts from coffee and bark of willow (Salix purpurea and Salix myrsinifolia). Raw materials and their mixtures were characterized by multidirectional antioxidant activities; however, bioactive constituents interacted with each other. Synergism was observed for ability of inhibition of lipid peroxidation and reducing power, whereas compounds able to scavenge ABTS radical cation acted antagonistically. Additionally, phytochemicals from willow bark possessed hydrophilic character and thermostability which justifies their potential use as an ingredient in coffee beverages. Proposed mixtures may be used in the prophylaxis or treatment of some civilization diseases linked with oxidative stress. Most importantly, strong synergism observed for phytochemicals able to prevent lipids against oxidation may suggest protective effect for cell membrane phospholipids. Obtained results indicate that extracts from bark tested Salix genotypes as an ingredient in coffee beverages can provide health promoting benefits to the consumers; however, this issue requires further study.

The suitability of caffeinated drinks for children: a systematic review of randomised controlled trials, observational studies and expert panel guidelines

BACKGROUND

The increased availability of caffeinated drinks raises questions about the level of caffeine that is appropriate for children, as well as the benefits and risks associated with their consumption.

METHODS

Using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, this systematic review evaluates evidence from randomised controlled trials investigating the effects of caffeine on cognition, behaviour, mood and exercise performance in children. Observational studies and expert panel guidelines are also discussed.

RESULTS

One hundred and nine studies were found, with 11 randomised controlled trials and 13 observational studies meeting the criteria. High caffeine intakes (e.g. >5 mg kg(-1) body weight day(-1)) were associated with an increased risk of anxiety and withdrawal symptoms. However, smaller amounts were not linked with such effects and may benefit cognitive function and sports performance based on adult studies. The evidence suggests that children and adolescents should limit daily caffeine consumption to 2.5 mg kg(-1) body weight day(-1), equating to one or two cups of tea or one small cup of coffee. Lower contributors of caffeine, such as tea, may be more appropriate for children because they contribute to daily fluid intakes and provide flavonoids. By contrast, caffeinated soft drinks may be less suitable options for children as a result of their acidity, higher caffeine content, presence of added sugar (in some cases) and absence of bioactive compounds.

CONCLUSIONS

More studies are needed to determine the intakes that represent a risk and whether there may be benefits for alertness and sports performance with moderate intakes of caffeine.

The Emerging Health Benefits of Coffee with an Emphasis on Type 2 Diabetes and Cardiovascular Disease

Debate persists whether coffee is beneficial or problematic for human health. Coffee consumption has been associated with a decrease in risk of developing type 2 diabetes, and numerous epidemiological studies have demonstrated that healthy, habitual coffee drinkers are more protected from the risk of contracting diabetes than individuals who do not drink coffee. Coffee consumption has been associated with a reduced incidence of impaired glucose tolerance, hyperglycaemia and insulin sensitivity. Data suggest that several coffee components, such as chlorogenic acids, are involved in the health benefits of coffee. Various mechanisms for this protective effect have been proposed, including effects on incretin release, liver glucose metabolism and insulin sensitivity. Epidemiological data support numerous other health benefits for coffee, including reduced cardiovascular disease (CVD), a protective effect against some neurodegenerative conditions, a favourable effect on liver function and a protective effect against certain cancers These associations are based mainly on observational studies and are currently insufficient to recommend coffee consumption as an interventional strategy for risk reduction in type 2 diabetes and other metabolic diseases While excessive consumption can have adverse effects on some conditions, particularly in terms of sleep quality, these effects vary among individuals and most people do not have any symptoms from coffee drinking. Moderate coffee consumption is associated with no or little risk of severe diseases and may offer substantial health benefits. Thus, coffee is a safe, low-energy beverage and suitable for most adult people.

Depression in headaches: chronification

PURPOSE OF REVIEW

Recent evidence supports the suggestion that migraine is a chronic disorder with episodic attacks that increase in frequency in a subgroup of patients, transforming migraine into a refractory chronic condition with poor outcome and severe impact. Among the risk factors for migraine chronification depression figures notably. Early diagnosis and management of risk factors in migraineurs prevent migraine chronification and its consequences. The scope of this article is to review depression as a potential cofactor for migraine chronification.

RECENT FINDINGS

Population-based studies revealed that migraineurs often have symptoms of depression, with strongest associations for migraine with aura. Patients with depression also have an increased risk for migraine, migraine with aura in particular. Twin studies showed similar findings. This bidirectional relationship suggests that migraine and depression may share common causative factors, possibly genetically determined, that might control migraine chronification. Migraine patients may develop depression as a result of the demoralizing experience of recurrent and disabling headaches and depressed patients may develop migraine because of increased pain sensitivity, in the basis of a common genetic background.

SUMMARY

We suggest that clinicians consider depression as part of migraine management in order to optimize treatment and avoid migraine progression.

Migraine chronification

Migraine is a disorder with variable natural history. In some sufferers, migraine evolves over time into a state of headaches on more days than not. This process of migraine chronification is poorly understood, but risk factors have been clearly identified. Herein, we first discuss the role of heritability and of genetic risk factors on migraine chronification. We follow with a discussion of the role of comorbid conditions and environmental exposures. We suggest that clinicians consider risk factor modification as part of migraine management, aspiring to not just relieve current pain and disability, but to avoid migraine progression. Reducing attack frequency, avoiding medication overuse, appropriately using preventive drugs and behavioral therapies, and encouraging weight loss should be part of migraine therapy to improve current pain and disability and also to avoid future pain and disability by preventing chronification.

Methylxanthines and pain

Caffeine, an antagonist of adenosine A(1), A(2A) and A(2B) receptors, is known as an adjuvant analgesic in combination with non-steroidal anti-inflammatory drugs (NSAIDs) and acetaminophen in humans. In preclinical studies, caffeine produces intrinsic antinociceptive effects in several rodent models, and augments the actions of NSAIDs and acetaminophen. Antagonism of adenosine A(2A) and A(2B) receptors, as well as inhibition of cyclooxygenase activity at some sites, may explain intrinsic antinociceptive and adjuvant actions. When combined with morphine, caffeine can augment, inhibit or have no effect depending on the dose, route of administration, nociceptive test and species; inhibition reflects spinal inhibition of adenosine A(1) receptors, while augmentation may reflect the intrinsic effects noted above. Low doses of caffeine given systemically inhibit antinociception by several analgesics (acetaminophen, amitriptyline, oxcarbazepine, cizolirtine), probably reflecting block of a component of action involving adenosine A(1) receptors. Clinical studies have demonstrated adjuvant analgesia, as well as some intrinsic analgesia, in the treatment of headache conditions, but not in the treatment of postoperative pain. Caffeine clearly exhibits complex effects on pain transmission; knowledge of such effects is important for understanding adjuvant analgesia as well as considering situations in which dietary caffeine intake may have an impact on analgesic regimens.

Sleep and headache

There is a strong interaction between sleep and headache. Sleep and headache disorders overlap epidemiologically, and share elements of anatomy and physiology. Perhaps as a result, their treatment is often mutually interdependent. Despite this, headache and sleep disorders tend to be treated separately, by different subspecialties of neurology. The headache disorders and their relationship to sleep, the commonalities of headache and sleep pathophysiology, and headache disorders that are particularly susceptible to sleep modulation (and vice versa) are reviewed. Practical management advice for sleep-modulated headaches is provided.

What predicts the change from episodic to chronic migraine?

PURPOSE OF REVIEW

Because migraine worsens in a sizeable subgroup of sufferers, but not in most, identifying factors that predict the change from episodic into chronic migraine is of extreme interest and should be seen as a priority in headache research.

RECENT FINDINGS

Potentially remediable risk factors include frequency of migraine attacks, obesity, excessive use of medications containing opioids and barbiturates, caffeine overuse, stressful life events, depression, sleep disorders and cutaneous allodynia.

SUMMARY

While we wait for evidence regarding the benefits of risk factor modifications in the prevention of chronic migraine, several interventions are justifiable based on their other established benefits. For example, decreasing headache frequency with behavioral and pharmacological interventions will decrease current disability even if it does not modify clinical course. Monitoring the body mass index and encouraging maintenance of normal body weight is good practice in patients with and without migraine. Avoiding overuse of caffeine is desirable apart from its potential benefit in preventing progression. Sleep problems should be investigated and treated. Psychiatric comorbidities should be identified and addressed. Medications containing opioids and barbiturates should be reserved for a few selected cases of migraine, and their use should be monitored. For these interventions, the possibility of preventing progression may motivate clinicians to offer good care and patients to engage in the treatment plan.