Kinetic tremor: Differences between smokers and non-smokers

Abstract

Tremor is among the acute effects of nicotine exposure. Published studies have focused on smokingrelated postural (static) hand tremor rather than kinetic tremor (tremor during hand use), and gender differences in smoking-related tremor have not been examined. In a group of adults who were sampled from a population (mean ± SD = 65.7 ± 11.5 years, range = 18 -92 years), the investigator assessed whether the severity of postural and kinetic tremors differed in smokers versus non-smokers, and whether this difference was influenced by gender. Twenty-seven (9.9%) of 273 subjects were current smokers. Greater tremor was observed in smokers than non-smokers during a variety of activities (drawing a spiral, using a spoon, finger-nose-finger maneuver, all p < 0.05) and smokers had a higher total tremor score than non-smokers (5.15 ± 3.06 vs. 3.41 ± 2.88, p < 0.01), even after adjusting for age, caffeine intake and other potential confounding factors. The difference between smokers and non-smokers in terms of hand tremor was more apparent in women than in men. In women, the number of cigarettes smoked on the day of testing was weakly correlated with the total tremor score (r = 0.17, p = 0.03). In summary, smokers had more kinetic hand tremor than nonsmokers. This difference between smokers and non-smokers was more apparent in women than in men. These results suggest that smoking habits should be considered carefully in order to avoid overor underestimating the effects of occupational and non-occupational exposures to other tremorproducing neurotoxins.

Tremor in School-Aged Children: A Cross-Sectional Study of Tremor in 819 Boys and Girls in Burgos, Spain

“…We found that tremor scores in the left hand were higher than those in the right (usually dominant) hand. A study of 273 normal adults in New York similarly reported that tremor scores in the left hand were higher than those in the right hand [16] . Motor control, in general, is superior in the dominant than non-dominant arm, and this is one possible explanation.…”

“…Having rigidly fixed task goals places more pressure on the subject, which worsens their tremor [15] . Also, tremor on spirals was previously rated in a study of 273 normal adults in New York [16] but these results are difficult to compare again because spirals were drawn free-hand and furthermore, a rating of 0.5 was not used in that study, which likely resulted in lower tremor scores in that study. The other possibility, alluded to above, is that tremor may indeed be more common in children than previously suspected and this could be an additional feature of an immature motor-coordination/ cerebellar system.…”

“…There are no other data in children but there are similar data in adults. A clinical study of 273 normal adults in New York (age 65.7 8 11.5 years, range 18-92) similarly reported that tremor scores in males were greater than those in females [16] . An accelerometric study of 117 normal German adults aged 20-94 noted a trend for tremor amplitude to be higher in males than females but this trend did not reach statistical significance [13] .…”

Smoking, Dopamine Transporter, and Hand Tremor

“…Nicotine is believed to act by binding the nico- tinic cholinergic receptors in skeleton muscle. [12][13][14] This study was not designed to capture the acute effects of smoking; tremor was not measured in smokers immediately after they smoked a cigarette. The interest of our study was the nonacute effects of smoking on the frequency of hand tremor.…”

“…It has been reported that tobacco smoking increased tremor. [12][13][14] Some studies reported an inverse association between smoking and Parkinson disease (PD). [15][16][17] We are interested in differentiating the hand tremor in smokers from that in Parkinsonism.…”