title: The effects of cannabis on heart rate variability and well-being in young men.
abstract: BACKGROUND
  The effects of cannabis use on the autonomic regulation of the heart had been identified in tests with volunteers. We studied these effects of cannabis use on young adults in everyday life.
  
  
  METHODS
  We measured heart rate variability (HRV) and well-being (WHO-5 score) in young men during a routine medical examination. Seventy-two men were identified with a positive drug screening test solely for tetrahydrocannabinol. The comparison group consisted of 72 men, matched according to age and body mass index, who used no illicit drugs or pharmaceuticals.
  
  
  RESULTS
  In the cannabis group, HRV was significantly increased compared to the control group. The median value of root mean square of successive differences (RMSSD) at rest was 56.2 ms in the drug users and 48.6 ms in the controls (p<0.05). The ratio of low-to-high frequency was higher in the controls (median 1.87 vs. 1.62; p<0.05). Psychological well-being, measured by WHO-5 score was significantly lower in cannabis users.
  
  
  CONCLUSIONS
  Our data support the hypothesis that the use of cannabis leads to a change in cardiovascular sympathovagal balance.
authors.affiliation: Institute and Outpatient Clinic for Occupational, Social and Environmental Medicine of the University Erlangen-Nuremberg, Erlangen, Germany. klaus.schmid@rzmail.uni-erlangen.de
authors.forename: K
authors.initials: K
authors.lastname: Schmid
authors.forename: J
authors.initials: J
authors.lastname: Schönlebe
authors.forename: H
authors.initials: H
authors.lastname: Drexler
authors.forename: M
authors.initials: M
authors.lastname: Mueck-Weymann
mesh_terms: D000203:Activities of Daily Living; D000293:Adolescent; D002186:Cannabinoids / Q000494:pharmacology*; D002188:Cannabis / Q000378:metabolism*; D016022:Case-Control Studies; D006339:Heart Rate / Q000187:drug effects*; D006801:Humans; D008297:Male; D012189:Retrospective Studies; D055815:Young Adult
chemical_list: D002186:Cannabinoids