Decreased Copper Level in the Blood Serum of Male Stutterers and the Occurrence of the Vibratio Brevis Phenomenon

Abstract

The blood serum copper level and the phonation start were investigated in sixteen male subjects with developmental stuttering (mean age = 25.8 years). A statistically significant decrease in blood serum copper level was revealed in the stutterers under study. The differences between their mode and mean values and that of the control group were 4.6 µmol/l and 3.1 µmol/l, respectively. The negative linear regression between the copper level in serum and the vibratio brevis phenomenon was registered in the stutterers under study. A decreased copper level can be involved in the biochemical abnormalities of male developmental stutterers and it can be included among the factors participating in pathophysiology of an uncertain phonation start.

Copper in Developmental Stuttering

“…The result from Pesak and Opavsky [11] of low serum Cu in stuttering men was supported by a pilot study of stuttering men in our laboratory, without a control group (n = 23, plasma Cu = 14 mol/l vs. 14.1 mol/l Cu in the study by Pesak and Alm Opavsky [11] ). The pilot study also indicated a low level of Cp and a high level of estimated free Cu.…”

“…Alpha was set at 0.05 for all statistical tests. One-tailed tests were used for plasma Cu and Cp, based on the result of Pesak and Opavsky [11] . A two-tailed test was used for estimated free Cu.…”

“…A group of 16 male persons with developmental stuttering had signifi cantly lower mean serum Cu levels than controls (p ! 0.001): 14.1 mol/l (SD 2.1 mol/l) in the stuttering group compared with 17.2 mol/l (SD 2.3 mol/l) in the control group [11] , making a difference in means of 3.1 mol/l. Furthermore, the level of Cu showed a negative correlation (r = -0.57) with the severity of stuttering (uncertain phonation starts).…”

“…A possible relation between copper (Cu) and developmental stuttering is suggested in a study by Pesak and Opavsky [10,11] . A group of 16 male persons with developmental stuttering had signifi cantly lower mean serum Cu levels than controls (p !…”

“…The primary purpose was to replicate the study by Pesak and Opavsky [11] of Cu in men with stuttering, and to expand it by estimating the level of free Cu based on an analysis of Cp. In the present study also females were included, but the statistical analysis was limited to men, because of diffi culties in achieving a suffi cient number of female participants who stutter, especially since the level of Cu is affected by estrogenic contraceptives.…”