Hand tremor related to smoking habits and the consumption of caffeine in male industrial workers.
Tremor was measured in 49 smokers/snuffers and in 49 non-smokers/non-snuffers in a cross-sectional study. The Kløve-Matthews static steadiness test and TREMOR 7.0 from the CATSYS test system were used to assess the hand tremor. The creatinine (cr) corrected arithmetic mean concentrations of cotinine in urine were 11 microg/g cr (range 0.1-430) in the non-smokers/non-snuffers compared to 1,417 microg/g cr (range 45-3,780) in the smokers/snuffers. The geometric mean urinary caffeine concentrations were 797 microg/g cr (range 0.5-13,330) in the non-smokers/non-snuffers versus 654 microg/g cr (range 0.9-7,470) in the smokers/snuffers. Increased tremor was found in the group of smokers/snuffers compared to the non-smokers/non-snuffers for several parameters on the tremor measurements, e.g. geometric mean tremor intensity of 0.14 m/s(2) (range 0.09-0.40) in the smokers/snuffers versus 0.11 m/s(2) (range 0.07-0.22) in the non-smokers/non-snuffers for the dominant hand were quantified. Also the mean scores on the static steadiness test were inferior in the smokers/snuffers, in particular for the number of touches. The results further indicate that the frequency dispersion is smaller in the smokers/snuffers compared to the non-smokers/non-snuffers. No systematic association was observed between the biomarkers of nicotine and caffeine exposure and the tremor measurements. However, older age appeared to be an important predictor for the magnitude of tremor in the smokers/snuffers, but not in the non-smokers/non-snuffers.
National Institute of Occupational Health, P.O. Box 8149 Dep, N-0033 Oslo, Norway. dag.ellingsen@stami.no
Dag G
DG
Ellingsen
Rita
R
Bast-Pettersen
Jon
J
Efskind
Merete
M
Gjølstad
Raymond
R
Olsen
Yngvar
Y
Thomassen
Paal
P
Molander
D000328:Adult; D000368:Aged; D000704:Analysis of Variance; D002104:Cadmium / Q000097:blood; D002110:Caffeine / Q000009:adverse effects*; D000697:Central Nervous System Stimulants / Q000009:adverse effects*; D002851:Chromatography, High Pressure Liquid / Q000379:methods; D003404:Creatinine / Q000652:urine; D003430:Cross-Sectional Studies; D006184:Habits; D006801:Humans; D008297:Male; D008875:Middle Aged; D016272:Occupational Health; D015203:Reproducibility of Results; D012720:Severity of Illness Index; D012907:Smoking / Q000009:adverse effects* / Q000652:urine; D014202:Tremor / Q000139:chemically induced*
D000697:Central Nervous System Stimulants; D002104:Cadmium; D002110:Caffeine; D003404:Creatinine