Clinical and demographic characteristics of people who smoke versus inject crystalline methamphetamine in Australia: Findings from a pharmacotherapy trial

Correlates of poor oral health related quality of life in a cohort of people who use methamphetamine in Australia

OBJECTIVES

Methamphetamine use impacts oral health, but little is known about its impacts on oral health related quality of life (OHRQoL). In this study we examined OHRQoL in a cohort of people who use methamphetamine and assessed associations with sociodemographic, behavioural, psychosocial and dental service utilisation correlates. A secondary aim was to examine the relationship between methamphetamine route of administration and OHRQoL, to test whether smoking the drug is associated with reduced OHRQoL.

METHODS

Cross-sectional analysis was performed, using data from VMAX, a cohort of people who use methamphetamine at least monthly in Victoria, Australia (n = 194). Utilising the oral health impact profile (OHIP-14), we assessed three OHRQoL outcomes: OHIP-14 prevalence, OHIP-14 extent and OHIP-14 severity. Regression analyses examined associations between independent variables and the three OHIP-14 outcome measures.

RESULTS

A significant segment of the cohort (35%) reported poor OHRQoL. Overall, no statistically significant association was detected between methamphetamine route of administration and the three OHIP-14 outcomes. Participants living in rural areas, with moderate-to-severe self-reported depression and with methamphetamine dependence had significantly worse OHRQoL levels, which persisted after adjusting for other covariates.

CONCLUSION

Overall, VMAX cohort participants reported reduced OHRQoL levels. Our findings highlight the need for upstream interventions to improve the OHRQoL of people who use methamphetamine, with specific focus on those living in rural locations. Further research on the links between OHRQoL and mental health among people who use methamphetamine is required.

Urinary profiles of methoxyphenamine and its metabolite after inhalation of methoxyphenamine smoke in humans: aiming to distinguish between active and passive exposure

PURPOSE

Methamphetamine (METH) is commonly abused through smoking. However, the lack of evidence regarding differences in urinary METH excretion after its active and passive inhalation has resulted in complications where the accused claims passive exposure. This study aimed to determine the differences in urinary excretion after active and passive inhalation of the drug, using methoxyphenamine (MPA) as a model for METH.

METHODS

Body temperature and locomotor activity were measured in mice as indicators of central nervous system toxicity. Six healthy adult male subjects were exposed to passive or active inhalation of MPA smoke in a small room, and urine samples were taken. MPA concentrations were measured using liquid chromatography-tandem mass spectrometry (LC-MS/MS).

RESULTS

There were no signs of toxicity in mice exposed to MPA smoke, ensuring the safety of the clinical study. Urinary MPA concentrations were significantly lower with passive inhalation compared with those of active inhalation. The maximum urinary MPA concentration in passive inhalation was 13.4 ng/mL, which was 1/60 of active inhalation with 800 ng/mL. The urinary excretion in passive inhalation until 24 h was 8.21 μg, which was 1/76 of active inhalation with 625 μg.

CONCLUSIONS

Since METH and MPA are expected to be excreted similarly, urinary METH concentrations in passively exposed persons are expected to be lower than the cutoff value of the screening kit. If the urine screening test is positive, the suspect should be considered a METH user.

TRIAL REGISTRATION NUMBER

jRCTs031210604, registration date: Feb. 9, 2022.

Cross-border Activities Associated With Pattern of Amphetamine-type Stimulants Usage Among Drug Users in Southwest of China

Cross-border activities are possibly associated with the use of amphetamine-type stimulants (ATS), this study was to explore poly-substance of ATS use and influencing factors among ATS use populations in southwest China. A cross-sectional study was conducted by response driven and continuous samplings from January to July 2021. Descriptive, univariate and logistic regression were carried out. ATS users accounted for 95.6% of the target population, of whom one-third had cross-border experiences with 4.1% of the cross-border purchase of drugs. ATS users were mainly over 31 years old (53.9%), male (98.7%), minority (79.1%), and unmarried (72.7%). Cross-border users consumed more ketamine (8%) and methamphetamine (40%) (P < .05). After adjusting for socioeconomic-demographic factors, cross-border activity [OR: 0.336 (0.141, 0.799)], occupation [OR: 0.273 (0.080, 0.929)], injecting drug behavior [OR: 6.239 (1. 087, 35.811)], frequency [OR: 0.251 (0.073, 0.859)], and ATS use location [OR: 2.915 (1.040, 8.168)] were possible factors influencing ATS use patterns (P < .05). Cross-border activity may be associated with polydrug use, especially predominantly methamphetamine use, among ATS users along the Southwest border. It implied that the focus of drug prevention and control in border areas should be on cross-border populations.

Demographic and geographic shifts in the preferred route of methamphetamine administration among treatment cases in the US, 2010-2019

BACKGROUND

Methamphetamine use disorder has increased rapidly in the past decade. Injecting is also increasing and has multifaceted implications for disease severity, overall health, and treatment outcomes, but less is known about where or among whom injecting has shifted the most. This national study assessed temporal changes in the preferred route of methamphetamine administration by race/ethnicity and within urban/rural geographies.

METHODS

We used the Treatment Episode Dataset-Discharges (2010-2019) to identify outpatient treatment cases who reported methamphetamine as their primary drug of choice at admission (N = 531,799; 2010 n = 33,744; 2019 n = 81,885). We created a combined variable indicating race/ethnicity and the rural/urban location of treatment, and used logistic regression to model the predicted probability of cases reporting injection, smoking, or snorting as their preferred route of administration. We included an interaction term to determine differences over time (race/ethnicity/rurality*year).

RESULTS

Across all years, smoking methamphetamine was the most common route of administration (66%), followed by injection (24%) and snorting (10%). Over time and among most sub-groups, the rates of injection increased while the rates of smoking decreased. Compared to 2010, the odds of injecting methamphetamine in 2019 were highest among Black cases in urban areas (aOR = 2.30, 95% CI = 1.76-3.00, p < 0.0001).

CONCLUSION

Increasing methamphetamine injection was most pronounced among Black treatment cases in more urban areas, which is in contrast to the longstanding narrative that methamphetamine is a White and rural drug. Methamphetamine prevention, treatment, and harm reduction should target populations with high injection prevalence and growing incidence.

Health Service Use for Mental Health Reasons in a Cohort of People Who Use Methamphetamine Experiencing Moderate to Severe Anxiety or Depression

This study examined health service use for mental health reasons in a cohort of people who use methamphetamine and experience anxiety or depression. Data were derived from baseline surveys of a subset of 429 participants from the ‘VMAX’ study. Anxiety and depression were measured using the Generalized Anxiety Disorder-7 instruments and the Patient Health Questionnaire-9. Sequential logistic regression determined correlates of health service use for mental health reasons. Lower odds of health service use for mental health reasons were evident for those living in a medium/small rural town (aOR = 0.27, CI = 0.12, 0.62), ≥ weekly methamphetamine use (aOR = 0.51, CI = 0.27, 0.99), and not utilising professional support for methamphetamine use in the 12 months prior (aOR = 0.19, CI = 0.12, 0.30). People who use methamphetamine frequently use health services for mental health issues. Further work is needed to determine the effectiveness of these services for this population.

Efficacy of Repetitive Transcranial Magnetic Stimulation in Patients With Methamphetamine Use Disorder: A Systematic Review and Meta-Analysis of Double-Blind Randomized Controlled Trials

BACKGROUND

Repetitive transcranial magnetic stimulation (rTMS) has demonstrated therapeutic potential for treating patients with methamphetamine use disorder (MUD). However, the most effective target and stimulation frequency of rTMS for treating MUD remains unclear. This meta-analysis explored the effect of rTMS on MUD.

METHODS

In this study, PubMed, Cochrane Systematic Reviews, and the Cochrane Collaboration Central Register of Controlled Clinical Trials were searched electronically for double-blind randomized controlled trials that used rTMS for treating MUD. We used published trials to investigate the efficacy of rTMS in MUD up to March 5, 2022, and pooled studies using a random-effect model to compare rTMS treatment effects. Patients who were diagnosed with MUD according to the criteria of the Diagnostic and Statistical Manual of Mental Disorders were recruited. Clinical craving scores between baseline and after rTMS were compared using the standardized mean difference (SMD) with 95% confidence intervals (CIs). The heterogeneity of the included trials was evaluated through a visual inspection of funnel plots and the I² statistic.

RESULTS

We identified seven trials with 462 participants with MUD that met the inclusion criteria. All the studies evaluated craving scores, with rTMS demonstrating a more significant effect than the sham treatment on reducing craving scores (SMD = 0.983, CI = 0.620-1.345, p ≤ 0.001). A subgroup meta-analysis revealed that intermittent theta-burst stimulation (iTBS) had a greater positive effect than 10-Hz rTMS. A metaregression revealed that the SMDs increased with the increase in baseline craving scores, whereas they decreased with the increase in the proportion of men and duration of abstinence.

CONCLUSION

The meta-analysis suggests that rTMS may be associated with treatment effect on craving symptoms in patients with MUD. iTBS may have a greater positive effect on craving reduction than 10-z rTMS.