Personality, depression, and premorbid lifestyle in twin pairs discordant for Parkinson’s disease
- aDepartment of Neurology, Medical University of Lubeck, Germany, bNeurological Clinic, Kantonsspital St Gallen, Switzerland
- Dr Peter Vieregge, Department of Neurology, Medical University of Lubeck, Ratzeburger Allee 160, D-23538 Lubeck, Germany. Telephone 0049 451 500 2928; fax 0049 451 500 2489.
- Received 27 July 1996
- Revised 29 July 1997
- Accepted 31 July 1997
Present personality traits (Freiburg personality inventory, FPI-R), depression (von Zerssen’s depression scale), and self assessed state of health were evaluated in 15 twin pairs (six monozygotic and nine dizygotic; mean age 62.5 years) discordant for idiopathic Parkinson’s disease and in 17 unrelated healthy control subjects. The twins had additional questionnaire based interviews on premorbid lifestyle.
For disability, twins with Parkinson’s disease scored lower on FPI-R than controls in “achievement orientation” and “extraversion”, higher in “inhibitedness”, “somatic complaints”, and “emotionality”. They scored higher for depression and for state of health than unaffected twins and controls. For zygosity, monozygotic twins scored lower than dizygotic twins in “achievement orientation”, “aggressiveness”, and “strain”. Monozygotic twins had less “achievement orientation” and “extraversion” and more “somatic complaints” than controls. Monozygotic twins had a lower within pair difference than dizygotic twins in “social orientation”. During premorbid times the affected twin with later Parkinson’s disease was estimated to have been “less often the leader” in the twin pair.
Although small in sample size, this twin study indicates a genetic impact for some personality features beyond the Parkinson’s disease motor syndrome.