Cardiovascular Complications of Marijuana and Related Substances: A Review

Cannabinoid-sensitive receptors in cardiac physiology and ischaemia

The classical cannabinoid receptors CB1 and CB2 as well as the cannabinoid-sensitive receptor GPR55 are widely distributed throughout the mammalian body. In the cardiovascular field, CB1 and CB2 crucially impact on diseases characterized by inflammatory processes, such as atherosclerosis and acute myocardial infarction. Both receptors and their endogenous ligands anandamide and 2-arachidonoylglycerol are up-regulated in the ischaemic heart in humans and animal models. Pharmacological and genetic interventions with CB1 and CB2 vitally affect acute ischaemia-induced cardiac inflammation. Herein, CB1 rather aggravates the inflammatory response whereas CB2 mitigates inflammation via directly affecting immune cell attraction, macrophage polarization and lymphocyte clusters in the pericardial adipose tissue. Furthermore, cannabinoids and their receptors affect numerous cardiac risk factors. In this context, cannabis consumption is debated to trigger arrhythmias and even myocardial infarction. Moreover, CB1 activation is linked to impaired lipid and glucose metabolism and therefore obesity and diabetes, while its antagonism leads to the reduction of plasma triglycerides, low-density lipoprotein cholesterol, leptin, insulin and glucose. On the other hand, activation of cannabinoid-sensitive receptors can also counteract unfavourable predictors for cardiovascular diseases. In particular, hypertension can be mitigated via CB1 agonism and impaired adrenoceptor responsiveness prevented by functional GPR55. Taken together, current insights identify the cannabinoid system as promising target not only to therapeutically interfere with the vasculature, but also to affect the heart as target organ. This review discusses current knowledge regarding a direct cardiac role of the cannabinoid system and points out its feasible therapeutic manipulation in the ischaemic myocardium.

Drug treatment strategies for insomnia in patients with post-traumatic stress disorder

INTRODUCTION

Insomnia is among the most reported sleep disturbances in patients with post-traumatic stress disorder (PTSD). The pervasiveness of this disorder among trauma-inflicted civilians and military personnel has been associated with reduced quality of life, impaired psychosocial functioning including cognitive impairments, negative mood swings, cardiovascular complications, and increased utilization of medical services.

AREAS COVERED

This review describes the current state of science with respect to the impact of the most dispensed pharmacological interventions for posttraumatic insomnia. At the present, there are no established treatment algorithms for PTSD-related insomnia. Pharmacotherapy offers an alternative treatment modality for patients with PTSD who fail or decline cognitive behavioral therapy (CBT). Selection of a hypnotic/sedative agent should be based on the patient's history, precipitating and perpetuating factors of insomnia, side effect profile, and potential medication-related interactions. Antipsychotics and benzodiazepines appear ineffective or are associated with significant harm in treating PTSD-related insomnia.

EXPERT OPINION

In the absence of randomized controlled trials, prescription patterns have been guided by anecdotal reports and expert opinion. Due to the complexity and multifactorial etiology of insomnia in PTSD, clinical investigations should examine available pharmacologic agents in comparative trials or in combination with CBT or complementary therapies to assess both short-term and long-term sleep outcomes in this population.

Prospects for the Use of Cannabinoids in Oncology and Palliative Care Practice: A Review of the Evidence

There is an increased interest in the use of cannabinoids in the treatment of symptoms in cancer and palliative care patients. Their multimodal action, in spite of limited efficacy, may make them an attractive alternative, particularly in patients with multiple concomitant symptoms of mild and moderate intensity. There is evidence to indicate cannabis in the treatment of pain, spasticity, seizures, sleep disorders, nausea and vomiting, and Tourette syndrome. Although the effectiveness of cannabinoids is limited, it was confirmed in neuropathic pain management and combination with opioids. A relatively favorable adverse effects profile, including no depressive effect on the respiratory system, may make cannabis complement a rather narrow armamentarium that is in the disposition of a palliative care professional.

Position Statement: A Pragmatic Approach for Medical Cannabis and Patients with Rheumatic Diseases

Objective.

Pain is one reason some rheumatology patients may consider use of medical cannabis, a product increasingly perceived as a safe and neglected natural treatment option for many conditions. Legalization of recreational cannabis in Canada will promote access to cannabis. Physicians must therefore provide patients with the best evidence-based information regarding the medicinal effects and harm of cannabis.

Methods.

The Canadian Rheumatology Association (CRA) mandated the development of a position statement for medical cannabis and the rheumatology patient. The current literature regarding the effects of medical cannabis for rheumatology patients was assessed, and a pragmatic position statement to facilitate patient care was developed by the Therapeutics Committee of the CRA and approved by the CRA board.

Results.

There are no clinical trials of medical cannabis in rheumatology patients. Evidence is insufficient about the benefit of pharmaceutical cannabinoids in fibromyalgia, osteoarthritis, rheumatoid arthritis, and back pain, but there is evidence of a high risk of harm. Extrapolating from other conditions, medical cannabis may provide some symptom relief for some patients. Short-term risks of psychomotor effects can be anticipated, but longterm risks have not been determined and are of concern.

Conclusion.

Despite lack of evidence for use of medical cannabis in rheumatology patients, we acknowledge the need to provide empathetic and pragmatic guidance for patient care. This position statement aims to facilitate the dialogue between patients and healthcare professionals in a mutually respectful manner to ensure harm reduction for patients and society.

Cannabinoids and Cardiovascular System

Cannabinoids influence cardiovascular variables in health and disease via multiple mechanisms. The chapter covers the impact of cannabinoids on cardiovascular function in physiology and pathology and presents a critical analysis of the proposed signalling pathways governing regulation of cardiovascular function by endogenously produced and exogenous cannabinoids. We know that endocannabinoid system is overactivated under pathological conditions and plays both a protective compensatory role, such as in some forms of hypertension, atherosclerosis and other inflammatory conditions, and a pathophysiological role, such as in disease states associated with excessive hypotension. This chapter focuses on the mechanisms affecting hemodynamics and vasomotor effects of cannabinoids in health and disease states, highlighting mismatches between some studies. The chapter will first review the effects of marijuana smoking on cardiovascular system and then describe the impact of exogenous cannabinoids on cardiovascular parameters in humans and experimental animals. This will be followed by analysis of the impact of cannabinoids on reactivity of isolated vessels. The article critically reviews current knowledge on cannabinoid induction of vascular relaxation by cannabinoid receptor-dependent and -independent mechanisms and dysregulation of vascular endocannabinoid signaling in disease states.

Recurrent STEMI Precipitated by Marijuana Use: Case Report and Literature Review

Marijuana abuse is rapidly growing and currently it is the most coimnon drug of abuse in the United States due to increased legalization for recreational and medicinal use. Delta 9-tetrahydrocannibol, the main psychoactive compound in marijuana, acts via the endocannabinoid system to elicit various cardiovascular physiological effects, and has been associated with many adverse cardiovascular effects such as acute coronary syndrome, arrhythmias, and sudden cardiac death that have previously been reported by our group and others. We present a case of a 30-year-old African-American male with no cardiovascular disease (CVD) risk factors with recurrent ST-segment elevation myocardial infarctions (STEMI) whose coronary angiography revealed recurrent 100% occlusion of the left anterior descending artery (LAD) in the setting of marijuana smoking. It was the patient's third STEMI with 100% occlusion of the LAD with each STEMI secondary to thrombosis of a different region of the LAD. Marijuana use was confirmed by urine toxicology screening at each STEMI presentation. Coronary angiography on multiple occasions was negative for stenosis of other epicardial coronary arteries, and coronary calcimn scoring was zero. Evaluation for other cardiovascular risk factors including family history of premature coronary artery disease, dyslipidemia, diabetes, and hypercoagulable disorders was negative. Further studies are required to elucidate the mechanisms of marijuana-associated coronary thrombosis and myocardial infarction.

Weighing the Benefits and Risks of Medical Marijuana Use: A Brief Review

Despite federal prohibition of medical marijuana possession, sale, and use, marijuana use continues to escalate as state legalization persists and expands. The purpose of this discussion is to provide a brief summary of the evidence regarding both potential benefits and risks of medical marijuana use.

Complete Heart Block From Chronic Marijuana Use

Marijuana is the most commonly used illicit drug in the world. Over the last decade, the potency of marijuana has increased tremendously. Its use is associated with harmful health consequences including adverse cardiovascular effects, such as arrhythmias, myocardial infarction, cardiomyopathy and stroke. It has been reported to cause bradycardia. This report describes the case of a 51-year-old female with no significant past medical history who presented with complete heart block due to chronic marijuana use, requiring a permanent pacemaker. To our knowledge, this is the first reported case of complete heart block due to chronic marijuana use. Advanced conduction system abnormalities can be a potential complication of chronic marijuana use, which the physicians need to be aware of. With increasing push for medical marijuana, physicians are likely to encounter more of such cases.

Prenatal exposure to tobacco and cannabis: Effects on autonomic and emotion regulation

Tobacco and cannabis are often used together in pregnancy and both have effects on children's regulatory system. Yet, little is known about the impact of co-use on the development of emotion regulation at the developmentally salient age of 2 years. One pathway linking co-exposure to tobacco and cannabis to toddler regulation may be via poor autonomic regulation in infancy. In addition, substance using mothers may be more dysregulated themselves, which may have direct effects on toddler regulation, but may also affect parenting, particularly maternal sensitivity during mother-child interactions. Thus, a second pathway linking exposure to toddler regulation may be via maternal dysregulation and low maternal sensitivity. We examined a conceptual model linking prenatal exposure to toddler regulation via these two pathways in a prospective sample (N = 247) of mother-child dyads recruited in the first trimester of pregnancy. Results indicated significant effects of co-exposure on poor autonomic regulation in infancy, which in turn predicted poor toddler emotion regulation. Mothers who used both tobacco and cannabis displayed lower sensitivity during play interactions with their infants. Maternal sensitivity was modestly stable from infant to toddler period and was predictive of higher toddler emotion regulation. Continued postnatal exposure to tobacco was also a significant, unique predictor of lower toddler emotion regulation. Results highlight the importance of examining co-exposure effects and suggest that this common pattern of use may be associated with higher infant/toddler risks.