# Associations of cannabis, alcohol, and tobacco use combinations with sleep health

## TL;DR

Using cannabis with alcohol or tobacco is linked to worse sleep quality and satisfaction compared to using cannabis alone.

## Contribution

The study reveals that polysubstance use, especially with cannabis, has a stronger negative impact on sleep health than cannabis alone.

## Key findings

- Polysubstance use is associated with worse sleep quality and satisfaction compared to cannabis alone.
- Higher cannabis dependence correlates with increased sleepiness and poorer sleep quality.
- Combined use of cannabis, alcohol, and tobacco is linked to higher sleep disturbance scores.

## Abstract

•Greater cannabis dependence linked with worse sleep quality and greater sleepiness.•Polysubstance use linked with worse sleep satisfaction compared to cannabis alone.•Polysubstance use linked with worse sleep scale scores.

Greater cannabis dependence linked with worse sleep quality and greater sleepiness.

Polysubstance use linked with worse sleep satisfaction compared to cannabis alone.

Polysubstance use linked with worse sleep scale scores.

Cannabis is often used alongside other substances, including cigarettes and alcohol. The objective of this study was to identify how the combination of these substances may affect sleep health.

Data from an online, national survey of 518 adults (35.2 ± 13.4 years old; 65% female) were analyzed. Respondents reported their cannabis, cigarette, and alcohol use. Hazardous cannabis use was assessed using the Cannabis Use Disorder Identification Test – Revised (CUDIT-R). Sleep, insomnia, and daytime sleepiness were assessed using the Pittsburgh Sleep Quality Index (PSQI), Insomnia Severity Index (ISI), and Epworth Sleepiness Scale (ESS), respectively. Sleep health was assessed using PSQI and ISI items about sleep quality, satisfaction, trouble staying awake, bedtime, waketime, sleep efficiency, and duration. Linear regression models examined associations of CUDIT-R and substance use with sleep scales and the individual sleep items, adjusting for sociodemographic factors.

One-quarter used only cannabis, 45% alcohol and cannabis, 12% cigarettes and cannabis, and 19% all three substances (polysubstance use). Average scores were 10.4 ± 5.7 on the CUDIT-R, 8.0 ± 4.1 on the PSQI, 11.3 ± 6.2 on the ISI, and 6.4 ± 4.2 on the ESS. A higher CUDIT-R was associated with higher PSQI (β = 0.09, 95% CI = 0.01, 0.17) and ESS scores (β = 0.16, 95% CI = 0.07, 0.26). Compared to individuals who only use cannabis, individuals with polysubstance use had higher PSQI, ISI, and ESS scores and reported worse sleep quality and less sleep satisfaction.

Sleep quality and satisfaction were most impaired by polysubstance use, whereas hazardous cannabis use increased sleepiness. The combined use of substances is detrimental to sleep health and highlights an area for public health messaging and awareness.