The effects of licit and illicit recreational drugs on prospective memory: a meta-analytic review

Abstract

Rationale There are no recent reports summarising the magnitude of prospective memory (PM) impairments in recreational drug users. Objective We performed a meta-analysis of studies (with a parallel group design) examining PM performance in users of common recreational drugs (including alcohol and tobacco) who were not intoxicated during testing. Studies were also evaluated for the presence of methodological bias. Methods Twenty-seven studies were included in the meta-analysis following literature searches of MEDLINE, EMBASE and PsycINFO. Effect sizes (standardised mean difference; SMD) were calculated separately for the effects of alcohol, cannabis, ecstasy, methamphetamine and tobacco use. The influences of drug use and study characteristics on effect sizes were explored using meta-regressions. Sources of study bias were also assessed. Results Heavy drinkers and regular drug users tended to perform worse than controls on event and time-based PM tasks. Effect sizes (standardised mean differences; SMDs) for event-based PM impairment across the different drug-using groups/heavy drinkers ranged between − 1.10 and − 0.49, with no 95% CI crossing 0.00. SMDs for time-based PM ranged between − 0.98 and − 0.70. Except for the CIs associated with the ES for smokers’ time-based PM performance, no CIs crossed 0.00. Conclusions Although all drug-using groups showed moderate-large impairments in event and time-based PM, effect sizes had low precision and moderate-high levels of heterogeneity. In addition, several methodological and reporting issues were identified in the majority of studies. As such, considerable uncertainty remains regarding the role of confounds and the magnitude of PM impairments in non-intoxicated recreational drug users. Electronic supplementary material The online version of this article (10.1007/s00213-019-05245-9) contains supplementary material, which is available to authorized users.

Cognitive Test Performance in Chronic Cannabis Flower Users, Concentrate Users, and Non-Users

“…Findings from the present study indicating detrimental effects of regular cannabis ( ower or concentrate) use are consistent with previous studies demonstrating moderate-sized detrimental effects on tests of verbal memory [20,21] and small-to-moderate sized effects on prospective memory [21,43,44] . Although effects of chronic cannabis use on executive functioning, attention, psychomotor speed, and decisionmaking tests have been previously reported [21,22] , we did not replicate them in this study.…”

Evidence on the acute and residual neurocognitive effects of cannabis use in adolescents and adults: a systematic meta‐review of meta‐analyses

“…More precisely, a meta‐analysis by Platt et al . [57], including six studies ( n = 356) and four studies ( n = 159), further distinguished between event‐ and time‐based prospective memory, respectively. There was a small and moderate‐to‐large effect size, with the cannabis groups performing worse on both types of tasks (event‐based: SMD = –0.31, CI = –0.63, −0.004 and time‐based: SMD = –0.70, CI = –0.80, −0.61).…”

“…The systematic search retrieved 2306 potential articles that were screened for eligibility after removing duplicates. Among the retrieved articles, 10 meta-analyses were selected providing 71 effects sizes [38,[51][52][53][54][55][56][57][58][59]. Each meta-analysis included two to 40 studies, with samples ranging between 65 and 5683 individuals (n = 43 761).…”

“…More precisely, a meta-analysis by Platt et al [57], including six studies (n = 356) and four studies (n = 159), further distinguished between event-and time-based prospective memory, respectively.…”

Cannabinoids and Their Role in Chronic Pain Treatment: Current Concepts and a Comprehensive Review

“…Many systematic reviews and meta-analyses have stated neurocognitive impairment with cannabis use including reasoning, association, flexibility, speed of information processing, verbal memory, language, motor inhibition, conceptual set-shifting, attention, working memory, learning impairments, visuospatial abilities, motor functioning, executive function/abstraction, verbal immediate recall, verbal delayed recall, verbal recognition, prospective memory, total memory, visual learning, verbal learning, prospective event-based and time-based Memories, forgetting, perceptual-motor and reaction time. [86][87][88][89][90][91][92][93][94][95] CARCINOGENIC SIDE EFFECTS Cannabis use increases the risk of non-seminoma testicular germ cell tumor (TGCT), and with insufficient evidence, oral, Pharyngeal, lung, and esophageal cancers. 96,97 However, some studies showed no increased risk of head and neck cancer, anal, penile, seminoma-TGCT, non-Hodgkin lymphoma, colorectal, or overall cancer.…”