Initial assessments suggest that the awareness of, and compliance with the LRCUG’s recommendations among cannabis users in Canada is reasonably good, but with room for improvement. Further evaluations are required. Because patterns and cultures of cannabis use are rather similar in New Zealand and North America, the LRCUG offer a readily available, credible and tested population health tool for reducing cannabis use related risks and the related public health burden in New Zealand. This is, generally, the case and pertinent irrespective of whether legalization will eventually be implemented or not. We urge relevant decision-makers and respectively mandated organizations to consider, adopting and effectively disseminating the LRCUG in the interest of advancing and improving cannabis use-related public health in New Zealand. Beyond the specific scenario of New Zealand, the LRCUG may serve as a valuable intervention concept or tool in at least two ways – especially in jurisdictions that are considering moving away from strict prohibition towards more health-oriented cannabis policy approaches. The LRCUG respond to the concrete need and create awareness for targeted prevention among both health policy-makers and the sizable populations of people who make the choice for cannabis use, and may concretely contribute to reduce the public health burden from cannabis through ‘lower-risk’ cannabis use. Depending on context, the LRCUG’s recommendations may need to be adapted to local norms and cultures related to cannabis use. Overall, the LRCUG offer a useful element towards ‘normalizing’ policy and intervention approaches for cannabis towards public health similar to those in place for other everyday activities that come with risks for health that are intended to be minimized.Dr. Fischer acknowledges support from the Hugh Green Foundation Chair in Addiction Research, Faculty of Medical & Health Sciences, University of Auckland; he furthermore reports grants and contract funding on cannabis-related topics from public only agencies.
Dr. Farrell directs the National Drug & Alcohol Research Centre, funded by the Australian Federal Government Department of Health, and has received unrestricted research funding from Indivior, Sequeris and Mundipharma and the Therapeutic Goods Authority in Australia to assess the effectiveness of medicinal cannabinoids and to develop clinical guidance. Dr. Newcombe has received grant funding from the New Zealand Health Promotion Agency,trim bin tray a public agency partially funded by the levy on alcohol produced or sold in New Zealand. Other authors report no related competing interests.Cannabis is one of the most consumed illicit drugs in India . Its consumption has increased in recent decades because of its decriminalization in some parts of the world. However, its cultivation and consumption are not fully legalised in India. The most commonly found and studied variety in India is Cannabis sativa. Therefore, in this study, cannabis refers to Cannabis sativa unless otherwise specifified. The current users of any cannabis product among the age group 10–75 years in India are 3.1 crores, constituting 2.8% of the general population . Bhang, ganja, and hashish are the common preparations of cannabis consumed in India. Bhang is the only preparation that is legalised in India. The prevalence of bhang and ganja/charas users is 2% and 1.2%,respectively . Although bhang users are comparatively more across the country, dependence is higher for ganja/charas, so it’s harmful effect. Smoking is the most preferred method of ganja/charas because the desired effects are rapid and reach within minutes. As many as 565 different chemical constituents have been isolated from Cannabis sativa till 2015, broadly divided into cannabinoids and non-cannabinoid groups . Cannabinoids have a specific C21 terpenophenolic structure and are more relevant to public health. As many as 120 cannabinoids are known, categorised into 11 different classes: ∆9-tetrahydrocannabinol , ∆8-THC, cannabigerol, cannabichromene, cannabinol, cannabitriol, cannabidiol, cannabinodiol, cannabielsoin, cannabicyclol and miscellaneous category .∆9-tetrahydrocannabinol is the primary psychoactive component of cannabis. ∆8-tetrahydrocannabinol, cannabinol, and cannabidiol are the other cannabinoids found in the plant act synergistically with THC . Cannabinoids affect the human body via two receptors, namely cannabinoid receptors, Type 1 and Type 2 . Both receptors are G-protein coupled receptors. CB-1 receptors are present exclusively in the brain, peripheral tissues, skeletal muscles, heart, liver, and fat. CB-2 receptors are present exclusively in spleen macrophages and immune cells like B & T lymphocytes, macrophages, neutrophils .
CB-1 & CB-2 receptor plays significant role in cardio-metabolic harm and atherogenic progression . In addition, both receptors are expressed in vascular and cardiac tissues like cardiomyocytes, endothelium, smooth muscle cells and their upregulation are responsible for various cardiac dysfunction . Cannabis is a potential risk factor for acute coronary episodes, particularly in young males. It triggers atrial ischemia, possibly affecting coronary microcirculation, leading to atrial fibrillation . In addition, cannabis initiates the formation of reactive oxygen species, thereby increases cellular oxidative stress. These reactive oxygen species via CB-1 receptor causes endothelial dysfunction and stimulates arterial vasospasm . Studies demonstrated the occurrence of sudden death in chronic cannabis users following strenuous activity, without any known history of coronary artery disease . The immediate effects of cannabis smoking include peripheral vasodilatation leading to postural hypotension & reflex tachycardia, conjunctival congestion and reduced work performance. Acute cannabis smoking has been shown to cause reversible changes in ECG parameters . Hypoxia secondary to chronic smoking is suggested to induce irreversible changes in coronary microcirculation, possibly by inducing atherosclerosis. Thus, it is believed that prolonged consumption of cannabis causes irreversible damage to cardiovascular system . The findings on the association between marijuana use and adverse cardiovascular outcomes have not always been replicated. Few studies also postulated the positive association of cannabis use and long term cardiovascular effects. As the number of countries legalizing cannabis is on the surge, concern about the long term safety profile of cannabis is obvious . Enough evidence in the form of case reports and retrospective studies are available suggesting the occurrence of acute cardiac events following recent cannabis intake even in healthy individuals . However, epidemiological studies suggesting the same are limited and the long-term effects of cannabis abuse on the cardiovascular system are still not fully known. The present study aims to explore cardiovascular abnormalities in asymptomatic cannabis smokers by comparing their electrocardiogram with tobacco smokers and non-smokers.A hospital-based, analytical, cross-sectional study was conducted at All India Institute of Medical Sciences , Rishikesh, Uttarakhand, from January 2018 to December 2019.
The sample size was decided on the basis of previous records of patient visits at the deaddiction clinic since we couldn’t find any published literature on a similar topic either done in our study region or India. The study included three groups; cannabis , tobacco and non-smokers . A total of 150 participants were selected, with 50 participants in each group. Mixing cannabis with tobacco is a common practice worldwide. According to some estimates, 90 percent of cannabis smokers mix marijuana with tobacco. Combining cannabis with tobacco increases the risk of dependence compared with using either drug alone . It is challenging to identify exclusive cannabis smokers. That is why we have added a second group of tobacco smokers in our study to counteract the effects of tobacco from cannabis group. The preparation of cannabis commonly used in Uttarakhand region is hashish , a black resinous material obtained by rubbing leaves and stems of cannabis plant with hands. Hashish, in this region, is smoked as ‘Joint’ after separating it into tiny pieces and mixing with crushed tobacco leaves, either filling this mixture in cigarettes, bidis, or clay pipes. On average, all cannabis users smoked 3 to 4 hashish joints/day for a period not less than five years. Other forms of cannabis users were excluded from the study. Based on the cumulative history given by the participants, a single joint contains about 0.3 to 0.5 gs of hashish and tobacco equal to the amount present in one standard cigarette. On average, tobacco users smoked 3 to 5 cigarettes/day for not less than five years. A standard cigarette weighs about 1 gram, containing 0.712 gs of tobacco .The cannabis smokers were self-reported consecutive patients who attended the de-addiction clinic of AIIMS Rishikesh at their first visit, without any diagnosed medical comorbidity. Tobacco smokers and nonsmokers were volunteered healthy individuals who responded to advertisements on our college website, hospital campus and nearby residential colonies. The age criteria for inclusion were between 18 and 40 years to avoid age as a risk factor for cardiovascular diseases for all the groups. Written informed consent was obtained from the participants before enrolment. Dependence on cannabis and tobacco was confirmed as per “International Statistical Classification of Diseases 10th revision Diagnostic criteria for research” . The Control group was free from any addiction or known medical ailment.
Participants were asked to abstain from smoking cannabis/tobacco or caffeinated drinks at least 2 h before ECG recording. ECG was recorded in resting supine position by a 12 lead BPL Electrocardiograph Model- CARDIART 6208 VIEW. Two ECGs were recorded in a gap of 5 min to eliminate artefacts.A medical history and a general physical examination, including pulse rate, respiratory rate, and systemic cardiovascular examination, were assessed to rule out any present illness. The following parameters were evaluated for comparison: Age, Heart rate, RR-interval, P-wave duration, PR-interval, QRS-complex duration, QT-interval, QTc-interval, ST-segment duration, pollen trim tray and T-wave duration. Each small box on an ECG graph paper represents 40 milliseconds along the horizontal axis. Heart rate was calculated by dividing 1500 with the number of small boxes present between two R-waves. RRinterval was calculated by counting the small boxes between the peak of two consecutive R-wave. PR-interval was calculated from the onset of P-wave until the onset of QRS-complex. QT-interval was calculated from the beginning of Q-wave till the end of T-wave. QTc-interval was calculated by dividing the QT-interval with square root of heart rate per minute . ST-segment was calculated from the beginning of S-wave till the beginning of T-wave. The count of small boxes was multiplied by 40 msec to get the duration in milliseconds.The acute adverse cardiovascular events of cannabis smoking are well documented in many studies and case reports. A study concluded that the risk of MI is almost five times within 60 min of cannabis smoking. The results of a systematic review found a significant association between cannabis use and coronary artery disease. Several other support the assertion that cannabis can significantly cause cardiac dysfunctions and mortality . Furthermore, some testimonies do not support the above findings. Recent research did not found any association between marijuana use and adverse cardiovascular outcomes. A community-based study found no consistent evidence of cumulative lifetime or recent marijuana with incidences of cardiovascular diseases. Such mixed opinion raises concern over the safety of long term cannabis intake either for recreational or therapeutic purposes. The present study evaluates the long term cardiovascular effects of cannabis smoking using ECG as a screening tool. The mean age of cannabis smokers in our study was comparatively younger compared to cigarette smokers and non-smokers . All the participants reported to us were males. Our results matched with numerous other studies and case reports. In a similar study, the mean age of cannabis users was 34.3 years, with 86% of participants being male . A retrospective study , enrolling 3854 participants, showed marijuana users were more likely to be men and younger than non-users.
The acute intake of cannabis causes tachycardia and an increase in supine blood pressure due to stimulation of the sympathetic nervous system and inhibition of the parasympathetic nervous system . Benowitz et al. reported the cardiovascular effects of continued cannabis ingestion over a trial period of 1 month. Tachycardia was seen in the initial trial phase but not in the later stage or after drug discontinuation. Heart rate returned to normal limits similar to predrug limits. Similarly, our study did not report any significant difference in heart rate among chronic cannabis smokers because repeated use of cannabis de-velops tolerance, masking the acute effects.Considering the QRS-complex, Benowitz and Jones proposed prolonged cannabis administration has an insignificant effect on QRS complex. On the contrary, our study showed a statistically significant shortening of QRS-complex in chronic cannabis smokers than tobacco smokers. This could be because we included participants with a history of cannabis use for more than five years. In addition, the sample size of our study was nearly four times the referenced study, hence disclosing the risk.