• Users predominantly young males with friends being the most common introducers 
• High rates of dependence, polysubstance use, significant psychiatric morbidity  

Methamphetamine users in Sri Lanka are predominantly young males with high rates of dependence, polysubstance use including nicotine and heroin, and significant psychiatric morbidity, specifically substance-induced psychosis and depressive disorder.

These findings were made in a non-peer reviewed research paper on "Methamphetamine use and psychiatric morbidity in Sri Lanka: Sociodemographic insights from a tertiary care clinic" which was authored by J. Galhenage (at the time of conducting the study, he was a Senior Registrar in Psychiatry attached to the Colombo University’s Psychiatry Unit at the National Hospital of Sri Lanka, Colombo, and at present, he is a Consultant Psychiatrist attached to the Teaching Hospital, Polonnaruwa), A. Isuru (attached to the Rajarata University's Medicine and Allied Sciences Faculty), and M. Dayabandara and R. Hanwella (both attached to the Psychiatry Department of the Colombo University's Medical Faculty), that is pending publication. 

Methamphetamine is the second most widely used illicit psychoactive substance globally (the UN Office on Drugs and Crime' "World drug report 2016"). Its use is associated with a spectrum of psychotic presentations, ranging from brief intoxication-related states to persistent substance-induced psychotic disorders that may resemble schizophrenia (J.G. Bramness and E.B. Rognli's "Psychosis induced by amphetamines"). There is a wide array of health problems related to methamphetamine use. Beyond the direct psychiatric effects, methamphetamine-induced psychosis contributes to social and occupational dysfunction, violence, and poor treatment outcomes (R. McKetin, D.I. Lubman, J.M. Najman, S. Dawe, P. Butterworth and A.L. Baker's "Does methamphetamine use increase violent behaviour? Evidence from a prospective longitudinal study", and S. Glasner-Edwards, L.J. Mooney, P. Marinelli-Casey, M. Hillhouse, A. Ang and R.A. Rawson's "Psychopathology in methamphetamine-dependent adults three years after treatment"). L. Hides, G. Chan, S. Dawe, R. McKetin, D.J. Kavanagh, R.M. Young, M. Teesson and J.B. Saunders's "Direction of the relationship between methamphetamine use and positive psychotic symptoms in regular methamphetamine users: Evidence from a prospective cohort study" also suggests a bidirectional relationship between methamphetamine use and psychotic symptoms, where each can exacerbate the other. In Sri Lanka, per the National Dangerous Drugs Control Board's (NDDCB) "Survey on methamphetamine (ice) use related prevalence in 2020", 50 methamphetamine users reported a mean age of initiation of 19 years, with a common concurrent use of heroin, cannabis, alcohol, cigarettes, and other stimulants. The highest number of methamphetamine-related arrests (1,762) was reported in the Colombo District in 2022 (the NDDCB's "Handbook of drug abuse information"). In Sri Lanka, methamphetamine use and related offences and arrests have increased over the last seven years since 2017. 

Methodology 

Per information provided exclusively to The Daily Morning, Galhenage et al.'s study was a cross-sectional, descriptive one conducted among methamphetamine users attending the Substance Use Disorder Management Clinic, outpatient psychiatry clinics, and inpatient psychiatry referrals from other wards of the Colombo National Hospital. Patients were excluded if they had been receiving antipsychotic or antidepressant treatment for more than a month, had a pre-existing mental illness prior to methamphetamine use, or were critically unwell. The study identified methamphetamine users in the Colombo District, Western Province. The study was conducted from September 2020 to February 2021, during the Covid-19 pandemic, when the number of methamphetamine users presenting was lower than expected.

Results

Of the 245 respondents, 239 (97.6%) were males and 147 (60%) were single. The mean age was 31.30 years (standard deviation [SD] 9.74 years), the minimum age was 15 years, and the maximum age was 63 years. The majority were educated up to Grade 11 (173, 70.6%) and 108 (44.1%) had an income less than Rs. 50,000 per month. The majority were from the Substance Use Disorder Management Clinic (196, 80%) followed by the outpatient psychiatry clinic (32, 13.06%) and inpatient psychiatry referrals (17, 6.9%).

Among methamphetamine users, 23 (9.4%) were in job category III (owners of businesses, sales representatives, managers, or administrators). The most common modes of referrals were by the user or family members (142, 58%) followed by courts (68, 27.5%) for medical treatments. A total of 112 (45.7%) had a history of imprisonment. A total of 76 (31%) had a history of substance use among first degree family members and 9.8% had a family history of major mental illness. The commonest mental illness, other than meth use disorder, was newly diagnosed substance induced psychosis (26, 10.6%) followed by depressive disorder (12, 4.9%) and schizophrenia (nine, 3.7%).

The majority of the meth users’ were resident within the Colombo District, and 83 (33.9%) were from Districts outside Colombo. The highest number of substance users was reported from the Colombo (52, 21.1%), Thimbirigasyaya (28, 11.4%) and Kolonnawa (23, 9.4%) Divisional Secretariat areas. 

The mean age of onset of methamphetamine use  was 29.16 years (SD 10.02 years), with the minimum age of onset of use being 14 years and the maximum age of onset of use being 62 years. The drug was first introduced by a friend (213, 86.9%), a workmate (five, 2%), a relation or spouse or partner (five, 2.4%), and a prison inmate (five, 2%). The source of the drug was an illegal drug market (138, 56.3%), and friends or relatives (100, 40.8%). The mode of administration was snorting by heating on a glass plate (241, 98.4%), smoking through a bong (three, 1.2%), and by using an aluminum coil and cylinder (one, 0.4%). The settings where the first use took place were at a friend's place (96, 39.2%), at home or a place near the home (47, 19.1%), at a party (39, 15.9%), at a workplace (24, 9.8%), at a funeral house (eight, 3.3%), in prison (six, 2.4%), in a rented room (four, 1.6%), at school (one, 0.4%), among others. The most common place of use was at a friend's place (124, 50.6%), at home or a nearby place (71, 29%), at a hotel or restaurant or dance hall (10, 4.1%), at a workplace (10, 4.1%), in a three-wheeler or car (two, 0.8%), at funeral houses (one, 0.4%) and in prison (one, 0.4%). The frequency of use was once a week or more but less than daily among 108 (44.1%), less than once a month among 55 (22.4%), daily among 39 (15.9%), and once a month or more but less than once a week among 27 (11%). The duration of use was more than one year among 111 (45.3%), 91 days to one year among 74 (30.2%), less than 30 days among 47 (19.2%), and 31 days to 90 days among 13 (5.3%). Last use was within one month to one year among 141 (57.6%), one day to seven days among 55 (22.4%), eight days to 30 days among 37 (15.1%), and within the last 24 hours among nine (3.7%). A total of 149 (60.8%) were dependent on methamphetamine (at least twice over the last 12 months - at least two of the 11 American Psychiatric Association’s Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition, diagnostic criteria were fulfilled over the past 12 months). A total of 234 (95.5%) concurrently used other drugs. The most common concurrent drugs were nicotine, and heroin. They were used weekly (228, 93.1%) or more often (181, 73.9%). The next most common drugs among methamphetamine users included cannabis (116, 47.3%), Pregabalin  (74, 30.2%) and alcohol (26, 10.6%). The other such substances used included Benzodiazepine, Corex-D, Tramadol, Thool or Mava, ecstasy, lysergic acid diethylamide, and Benzhexol/Trihexyphenidyl. 

The most common psychotic symptoms were somatic concerns, anxiety symptoms, grandiosity, depressed mood, hostility, suspiciousness, and hallucinating behaviour.

The analysis of the socio-demographic variables with the psychiatric ratings revealed several significant associations and all associations were statistically significant. Methamphetamine dependence was significantly associated with psychosis.

Discussion

A majority of the methamphetamine users (60%) were single males with a mean age of 31.30 years. A.R. Jayamaha, N.D. Dharmarathna, N.D. Herath, N.D. Ranadeva, M.M. Fernando, K.L. Samarasinghe, P.N. Amarabandu, B. Senanayake, T. Darshana, N. Renuka, I.H. Rajapakse, C.P. Gunasekara, L. Meegoda and N. Fernando's "The pattern of substance use and characteristics of the individuals enrolled in residential treatment at selected rehabilitation centres in Sri Lanka: A descriptive cross-sectional study" found that 60.5% were single and 98.5% were males. Approximately half of the methamphetamine users were reported to have a history of conflict with the law enforcement authorities, which aligns with increased methamphetamine and other substance-related imprisonments noted recently. A total of 13,720 were arrested by the law enforcement agencies in 2021 for methamphetamine related offences, and its use has risen considerably in the country during the 2021-2022 period. A family history of substance use was present among 9.8%. The majority of the users’ first introducer was a friend, and most had used methamphetamine at a friend’s place or their own home. No participant reported intravenous methamphetamine use, and eight (3.3%) users indicated that they started methamphetamine at night gatherings at funeral houses. The most common comorbid substances were tobacco (33.97%), and alcohol (18.76%), followed by heroin (14.25%). This study identified three common comorbid substances among methamphetamine users: tobacco, heroin and cannabis. A significant proportion met the criteria for methamphetamine and heroin codependence, although heroin use was not assessed using standard diagnostic criteria for dependency. This may be due to their commonly held belief that methamphetamine acts as an opioid substitute to counteract the effects of heroin (M.S. Ellis, Z.A. Kasper and T.J. Cicero's "Twin epidemics: The surging rise of methamphetamine use in chronic opioid users").

Methamphetamine-associated psychosis revealed a unique pattern of psychiatric symptoms. The most common mental illnesses were substance-induced psychosis (10.6%), depression and schizophrenia. P. McInnis and A. Lee's "Methamphetamine use in an early psychosis service: A cross-sectional, retrospective cohort study", using only 19 individuals, revealed schizophreniform disorder, schizoaffective disorder, bipolar affective disorder and unspecified psychotic disorder as the most common psychiatric illnesses among methamphetamine users. A Chinese study (H. Dong, M. Yang, L. Liu, C. Zhang, M. Liu, Y. Shen, H. Liu and W. Hao's "Comparison of demographic characteristics and psychiatric comorbidity among methamphetamine-, heroin- and methamphetamine-heroin co-dependent males in Hunan") found that both methamphetamine-dependents and methamphetamine-heroin codependent groups had a higher prevalence of current and lifetime risks of developing psychotic disorder. In this study, schizophrenia was diagnosed in only 3.7%. In M-F. Su, M-X. Liu, J-Q. Li, J.M. Lappin, S-X. Li, P. Wu, Z-M. Liu, J. Shi, L. Lu and Y. Bao's "Epidemiological characteristics and risk factors of methamphetamine-associated psychotic symptoms", the prevalence of methamphetamine-associated psychotic symptoms was 17%, and the top three psychotic symptoms were somatic concerns (36.7%), feelings of guilt (93, 36.7%) and excitement (33.9%). In this study, the most common psychiatric symptoms were suspiciousness, hostility, and depressed mood. In another Chinese study (J. Ma, X-J. Sun, R-J. Wang, T-Y. Wang, M-F. Su, M-X. Liu, S-X. Li, Y. Han, S-Q. Meng, P. Wu, J. Shi, Y-P. Bao and L. Lu's "Profile of psychiatric symptoms in methamphetamine users: Greater risk of psychiatric symptoms with a longer duration of use"), 57.6% of dependent individuals had any type of psychiatric symptoms including depression, anxiety and psychotic symptoms, a dose-response relationship was found, and psychiatric symptoms were more common, with psychotic symptoms associated with methamphetamine dependency and the increased duration of use.

In this study, 86 (36%) had above-average psychiatric rating scores which were significantly associated with the presence of dependence and methamphetamine use for more than 90 days. The association of psychosis with methamphetamine use within the last seven days may be due to transient psychotic symptoms in a proportion of methamphetamine users, which may not constitute a psychotic disorder (S. Glasner-Edwards and L.J. Mooney's "Methamphetamine psychosis: Epidemiology and management"). In methamphetamine induced psychotic disorder, symptoms must last beyond the expected effects of intoxication or withdrawal. Heroin use, Pregabalin use, and the marital status were significant predictors of above-average psychiatric rating scores among methamphetamine users.

Methamphetamine dependence was independently associated with a higher psychiatric symptom burden. 

These findings, according to Galhenage et al., underscore the urgent need for early detection, integrated treatment approaches, and targeted prevention strategies to mitigate the growing public health impact of methamphetamine use in Sri Lanka.