Tourette's Syndrome and Attention Deficit Disorder with Hyper activity: Are They Genetically Related?

Abstract

Based on a series of 250 consecutive, unselected patients with Tourette's syndrome (TS), all examined in a prospective manner, we address the relationship between TS and attention deficit disorder (ADD) with hyperactivity. ADD with hyperactivity was present in 62% of TS male patients under 21 years of age. Examination of family pedigrees suggested that the TS gene could be expressed as ADD with hyperactivity but without tics. In 91 patients with hyperactivity sufficient information was available to determine the duration from onset of hyperactivity to onset of TS symptoms. The mean was 3.0 years. For 18 patients treated with stimulants before the onset of tics (Group IIA: hyperactivity stimulant medication tics) this duration was 5.3 years. For 35 patients treated with stimulants after the onset of tics (Group IIB: hyperactivity tics stimulant medication) this duration was 1.6 years. The presence of a positive family history for TS was not significantly different in these two groups—72.2% vs. 78.8%. When all patients with a simultaneous onset of hyperactivity and tics were removed from Group IIB, the duration from onset of hyperactivity to tics was 4.0 years, still less than in Group IIA. The combined data suggest that patients with hyperactivity who develop tics after treatment with stimulants had ADD due to a TS gene and probably would have developed tics without stimulant treatment.