The health , economic , and social effects of cannabis use in Thailand

Controversy surrounds the harm and benefit of cannabis Background: use. Further research on the impact of cannabis might guide the government in developing appropriate policies. This research aims to examine the health, economic, and social effects of cannabis use in Thailand. From a prospective cohort of 261 cannabis users in Kalasin Methods: province, Thailand, we followed 45 cannabis users over 1 year as part of an in-depth study. Quantitative and qualitative data on the health, social, and economic consequences of use were gathered. In-depth interviews, participant observation by researchers during home visits , and self-report instruments were utilized. To supplement the cannabis users’ data, we also collected data from 10 health personnel, 16 community leaders, and 480 laypeople. Our results indicate that cannabis use causes health problems. Results: We determined the disability-adjusted life years of cannabis users and found a total loss of 120.09 years and a mean loss of 0.78 years. The possible economic impacts of cannabis treatment include medical expenses, loss of revenue for both cannabis users and their caregivers, and costs due to law enforcement and possible lawsuits. The economic costs measured during the study period totaled 1,561,460 baht, of which 1,347,950 was attributed to the costs of law enforcement and legal prosecution. However, we found no costs due to accidental losses. Cannabis does appear to not cause community conflict or crime. Despite this, cannabis use remains a social problem, and has been associated with outbreaks of illegal drug use. This study showed that using cannabis can harm users, their Conclusions: family, and society as a whole. This should be essential for policy advocacy.

Cannabis is the most commonly used illegal drug worldwide, with the fastest growing rate of use 1 . This may be due to growing research on the medical uses of cannabidiol (CBD) and delta-9-tetrahydrocannabinol (THC), both of which are found in cannabis plants and can be used to treat various medical diseases, including glaucoma 2,3 and epilepsy 4 . In addition, cannabis can be used to treat pain and reduce nausea in patients with cancer receiving chemotherapy or to increase the appetite of HIV patients 5,6 .
However, THC also binds to the brain's cannabinoid receptors, interfering with the body's natural cannabinoid system, resulting in possible euphoria, anxiety, hallucinations, or delusions 7 . For example, cannabis users are at least four times as likely to get in an accident while driving 8,9 . In addition, among employed workers, those using illicit drugs (including cannabis) are more likely to be fired 10 .
Cannabis has been recognized as a food ingredient and traditional herb throughout the history of Thailand, although it has been outlawed since 1934 11 . Although cannabis is illegal, the number of cannabis users is increasing throughout the country 12 . Increasingly, they are calling for the legalization of cannabis. Revision of such national policies, however, requires a considerable evidence base that should be taken into account. Thus, the health, economic, and social impacts of using cannabis should be explored. Such data could be of considerable benefit to policymakers as well as academics.

Study design
This was a prospective cohort study design. Kalasin province in the northeast of Thailand was selected as the study site because it is a major area of cannabis production.

Population and samples
A total of 261 cannabis users registered as patients in hospitals. Registered cannabis users in 2014 who settled in Kalasin province, a province chosen randomly from those with the greatest cannabis production in Thailand, were identified as the target population for this study, and were approached to participate in person at an appointment. All 261 agreed and gave their written consent to participate in a study on the burden of disease in April 2015. Of these, 58 cannabis users agreed and gave their written consent to participate in an in-depth study. These individuals gave their private telephone number to the research team and allowed the research team to visit them at home in April 2015. After 1 year, 13 cannabis users moved to other provinces or had lost contact with the research team. Thus, 45 cannabis users remained in April 2016. These 45 individuals lived in 16 communities in 10 districts in Kalasin province.
Besides cannabis users, 16 community leaders were recruited to provide information about community demographics and drug use. In addition, 480 laypeople from 16 communities (30 each of both sexes in various age groups) agreed to answer the Thai Addiction Stigma Scale 13 (for comparison with the cannabis users). All participants were recruited in April to May 2016.

Tools
In this study, investigators and research assistants were essential. One investigator had a PhD and over 20 years of experience in drug research, one had a PhD and 10 years of experience in drug research, and one had a master's degree with 5 years of experience in qualitative research. Assistance was provided by health officers who have worked with target communities for over 10 years.
A psychiatric nurse with a master's degree and over 20 years of experience working with drug addicts, developed three in-depth interview guidelines (for healthcare personnel, community leaders, and cannabis users). Diaries were created for cannabis users to self-report signs/symptoms, healthcare activities, healthcare and related expenditures, and cannabis-related expenditures. The Thai Addiction Stigma Scale (content validity index = 0.97, Cronbach's alpha = 0.77) 13 was used to gather data from the laypeople. This scale had a total score ranging from 16 to 120 and comprised 5 subscales: familiarity, risk perception, fear, social distance, and community response. Furthermore, data on burden of disease among cannabis users were gathered using the interview guidelines developed by Loeiyood 14 .

Data collection
In April 2015, data on medical history, cannabis use patterns, and personal characteristics were collected from cannabis users though in-depth interviews. A total of 261 cannabis users who gave their consent were interviewed at their home, without anyone else present, after their regular appointment at a hospital. At each appointment, cannabis users provided 30-60 minutes for the research team to interview them. When we did not reach data saturation for a particular participant, we asked participants to take part in another interview at their next appointment and repeated this until the data were saturated (ranging from 1 to 3 times). We did not use voice or video recording or take photographs of the interviews or users. However, notes were taken during the interview. For the 58 cannabis users who consented to the in-depth study, the research team visited them at home for another private interview and participant observation during daily activities on a monthly basis, half a day each. Again, recording devices were not used. Diaries were given to each cannabis user to enable them to record data on the symptoms and expenditures of cannabis use. This diary was exchanged with a researcher once per month based on appointments until April 2016. During the monthly appointments, cannabis users were asked to clarify what they had recorded in the diary and were interviewed in more detail. During the fieldwork period, we interviewed 10 healthcare personnel and 16 community leaders. The Thai Addiction Stigma Scale was administered to the laypeople in early 2016. On cannabis users' last appointment, around April 2016, they were interviewed about the burden of disease and their medical history in the past year.

Analysis
Data from cannabis users' diaries and interviews were triangulated with data from the health personnel and community leaders. Content analysis was employed for the interview data, while the health events in the diaries were tallied. To evaluate the burden of disease, we calculated users' disability-adjusted life years (DALYs) from their 1-year medical history. The direct economic costs, both public (e.g., hospital expenses for -medication, supplies, admission) and private (e.g., food, transportation, and others), of cannabis use were tallied. Furthermore, we calculated the economic losses based on individual non-working hours/days. The costs incurred from other cannabis-related events were also tallied.

Data analysis
Once data were collected from the participants, the researchers used data coding to categorized information. Data analysis was conducted by considering the essence of the content of the health, economic, and social effects of cannabis use in Thailand.

Ethics statement
During the data collection stage, participants provided their written informed consent. Personal identifiers (names, full addresses) were stripped from the dataset. This research project was approved by the Human Research Ethical Committee of Khon Kaen University (HE 571473) based on the principles of the Declaration of Helsinki and the Good Clinical Practice standards of the International Council for Harmonisation of Technical Requirements for Pharmaceuticals for Human Use (ICH).

Study background and demographic information
The 261 cannabis users we initially selected made 2,698 visits to healthcare facilities in the past 12 months due to illness. Furthermore, 150 out of these 261 users visited the hospital due to cannabis-related illness. Approximately 150 users reported psychiatric problems and 3 experienced multi-drug use. A total of 14 users had road accidents, 6 users were injured by others, and 1 user made a suicide attempt.
Of the 45 participants who completed the in-depth study, all were male and had an average age of 43.51 years. The majority were married (55.53%) and had primary degrees (53.33%), and 37.77% worked as farmers. For most respondents, alcohol was their first drug (53.33%), and they later moved to cannabis. The average age at which participants first used cannabis was 19.02 years. The primary method of cannabis use was bamboo pipes. Participants had used cannabis for an average of 26.86 years. All of them perceived that they were addicted to cannabis. The most common frequency of use was three times per day (42.22%), and the average amount was about 1 g per use.
When researchers followed up with 45 participants after one year, they examined the health, economic, and social effects of cannabis. While none of the users died over the study period, there was a considerable loss of DALYs, at 120.09, with a mean loss of 0.78. Interestingly, among the three users of multiple drugs, cannabis was not the gateway-they had used other drugs before cannabis

Health impacts
Although a number of cannabis users had received treatment for illness over the study year, they generally perceived themselves to be of good health. Of the 45 respondents, 3 reported that they had a preexisting medical condition (one had diabetes and two had epilepsy). One participant told researchers: "My mother and brother are diabetic. 15  In addition, 87.33% users reported that they did not believe they were abusing drugs, despite their continuous cannabis use. For example, respondents said: "I can repay everyone. People who use cannabis alone will be healthier. However, if cannabis is used in combination with other drugs like alcohol, then people might be exposed to certain health risks." "Most old people in the past, they smoked cannabis, and did not see anyone as crazy or schizophrenic. In contrast, it's good for smokers...good health and longevity."

Economic impacts
Of the 45 cannabis users, 17 reported contact with law enforcement since using cannabis is illegal in Thailand. Using data from the self-report diary, we analyzed the private costs of cannabis use, and found that economic losses tended to result from law enforcement-both direct costs (e.g., fines, lawyer fees, transportation) and indirect costs (for both the self and relatives, e.g., production losses, litigation, and accidental losses such as compensation for accident and injury and related costs).
The total medical costs for the cannabis users, including the treatment of addiction, amounted to 142,560 baht (4,537 USD), with an average of 3,168 baht (101 USD) per case. Meanwhile, the total of loss of income, other than prosecution amounted to 32,500 baht (1035 USD), with average of 723 bath (23 USD) per case.
The total costs related to law enforcement and prosecution litigation amounted to 1,445,330 baht (44,267 USD), with an average of 85,019 baht (2,604 USD) per case (range: 12.3-5997.1 USD). Of these total costs, direct costs for litigation (e.g., fines, lawyer fees, bailout) accounted for 1,230,000 baht (39,145 USD), or about 85.1% of all private costs, with an average of 72,353 baht (2,303 USD) per case (range: 0-5,360 USD). The indirect cost accounted for 14.9% of the total costs, and included loss of income during prosecution (82,266 baht or 2,519.6 USD) and caregiver expenses (133,064 baht or 4,075.5 USD), which included transportation/food/accommodation costs during prosecution (102,900 baht or 3,151.6 USD) and loss of caregiver income during prosecution (30,614 baht or 923.9 USD). In addition, the loss of income due to prosecution process was 38,450 baht (1212 USD), an average of 854 baht (27 USD) per case.
Interestingly, we found no costs associated with accidents or property destruction due to drug-related accidents. This may be because when individuals use cannabis, they are careful to keep to themselves or in small groups. Cannabis users do not drive and are often not social while under the influence, as demonstrated by the following responses: "Since using cannabis, I have never had an accident. I have never heard of anyone using cannabis having an accident. When you smoke cannabis, it puts you in a relaxing, calm mood and you are careful to smoke it by yourself…" "Do not connect accidents with cannabis use. Cannabis does not cause impulsive moods and thoughts like amphetamines or alcohol."

Social impact
Social impact in this study was defined as stigma related to cannabis. The 45 cannabis users lived in 16 communities. Within these 16 communities, the addiction stigma score of the 480 laypeople was analyzed. We found a mean stigma score of 84.23 with an SD of 13.44 (95% CI [83.15, 85.31]) and a range of 50 to 111 score. This indicates a moderate level of addiction.
Addiction stigma reflects the negative perception of drug use among community members, and scale scores reflect the degree to which community members attribute various problems in their communities to drug users, including cannabis users. Cannabis users, on the other hand, perceived that cannabis use itself did not cause these social problems, nor did it have an impact on their work or the likelihood of crime, as shown by the following responses:

Discussion
The study analyzed the effects of cannabis use and found that cannabis is not a gateway to the use of other additive drugs. These results are in contrast to those of previous studies 15 .
Participants that reported using cannabis medically might not use it over the long-term, but still reported a change in their perceived health status. Although this shift may be gradual, it reflects the findings of Lev-Ran et al., who conducted a literature review of 14 studies and found that cannabis users have a 17% lower risk of developing depression than do nonusers; in people who use large amounts of cannabis this number increases to a 62% lower risk of depression 16 .
Our study showed that cannabis use has a notable economic impact in terms of the government's incurred costs regarding medical treatment, loss of income (for the user and caregiver), and law enforcement and prosecution costs for cannabis-related offenses. Our findings of unemployment of cannabis use are similar to those from a previous study. Past-year job loss preceded pastmoth cannabis use, among those who were not using cannabis previously. Moreover, the prior cannabis use presented as a risk factor for unemployment 10 . In contrast, our findings differ from those of previous studies in that we did not find any costs associated with accidents. In the United States, for example, in 2006, more than one third of motorists who suffer a fatal road accident used cannabis either before or during their drive 9 . However, our results indicate that cannabis users are self-conscious of their impairment and do not use the drug before or during a drive.

Conclusions
Cannabis use led to a pronounced disease burden and considerable economic losses. However, it does not appear to lead to violence or crime within either the family or community. Despite this, the associated stigma of cannabis use might harm the community. Once the community has labelled drugs as an epidemic, the community begin surveilling the drugs much more intensively, thereby disrupting the normal lives of villagers.
This research admittedly has limitations. This study only included males, and the study period only covered 1 year. In addition, the findings might not be applicable to studies of cannabis use in other locations.

Data availability
Raw datasets have not been made available at the request of the ethics committee in order to maintain participant confidentiality. Access to the complete raw data can be obtained upon request and with the permission of Ethics Committee of Khon Kaen University (www.ekku.ac.th); since all data were collected in Thai, all data including quotes are only available in Thai. Anyone wishing to access the data should first contact the corresponding author who will facilitate contact with the ethical review board (Contact email: manopkanato@gmail. com). Access will be granted to researchers that wish to use the data for grant applications or similar.

Grant information
The authors would like to thank the Office of the Narcotics Control Board (ONCB75/2558) for funding support of this research project.