Hand function is altered in individuals with a history of illicit stimulant use

Verity Pearson-Dennett; Stanley C Flavel; Robert A Wilcox; Dominic Thewlis; Adam P Vogel; Jason M White; Gabrielle Todd

doi:10.1371/journal.pone.0115771

Hand function is altered in individuals with a history of illicit stimulant use

PLoS One. 2014 Dec 29;9(12):e115771. doi: 10.1371/journal.pone.0115771. eCollection 2014.

Authors

Verity Pearson-Dennett¹, Stanley C Flavel¹, Robert A Wilcox², Dominic Thewlis³, Adam P Vogel⁴, Jason M White¹, Gabrielle Todd¹

Affiliations

¹ School of Pharmacy and Medical Sciences and Sansom Institute, University of South Australia, South Australia, Australia.
² Department of Neurology, Flinders Medical Centre, South Australia, Australia; Human Physiology, Medical School, Flinders University, South Australia, Australia.
³ School of Health Sciences and Sansom Institute, University of South Australia, South Australia, Australia.
⁴ Speech Neuroscience Unit, University of Melbourne, Victoria, Australia.

Abstract

Use of illicit stimulant drugs such as methamphetamine, cocaine, and ecstasy are a significant worldwide problem. However, little is known about the effect of these drugs on movement. The aim of the current study was to investigate hand function in adults with a history of illicit stimulant use. We hypothesized that prior use of illicit stimulant drugs is associated with abnormal manipulation of objects. The study involved 22 subjects with a history of illicit stimulant use (aged 29±8 yrs; time since last use: 1.8±4.0 yrs) and two control groups comprising 27 non-drug users (aged 25±8 yrs) and 17 cannabis users with no history of stimulant use (aged 22±5 yrs). Each subject completed screening tests (neuropsychological assessment, medical history questionnaire, lifetime drug history questionnaire, and urine drug screen) prior to gripping and lifting a light-weight object with the dominant right hand. Horizontal grip force, vertical lift force, acceleration, and first dorsal interosseus electromyographic (EMG) activity were recorded during three trials. In trial one, peak grip force was significantly greater in the stimulant group (12.8±3.9 N) than in the control groups (non-drug: 10.3±4.6 N; cannabis: 9.4±2.9 N, P<0.022). However, peak grip force did not differ between groups in trials two and three. The results suggest that individuals with a history of stimulant use overestimate the grip force required to manipulate a novel object but, are able to adapt grip force in subsequent lifts. The results suggest that movement dysfunction may be an unrecognized consequence of illicit stimulant use.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Adolescent
Adult
Cannabis
Female
Hand / physiology*
Hand Strength / physiology
Humans
Illicit Drugs / pharmacology*
Lifting
Male
Methamphetamine / pharmacology*
Middle Aged
Motor Skills / drug effects*
N-Methyl-3,4-methylenedioxyamphetamine / pharmacology*
Neuropsychological Tests
Young Adult

Substances

Illicit Drugs
Methamphetamine
N-Methyl-3,4-methylenedioxyamphetamine

Grants and funding

This work was supported by the Ramaciotti Foundation (GT holds an Establishment Grant; ID2974/2010), National Health and Medical Research Council of Australia (GT holds a Career Development Award: ID 627003; APV holds an Early Career Research Fellowship: ID 1012302), Australian Government (VPD holds an Australian Postgraduate Award), and the University of South Australia (GT holds a Research SA Fellowship and Division of Health Sciences Research Grant, SCF held an Australian Postgraduate Award, and VPD holds a Top-up Scholarship. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.