Genetic and environmental contributions to stability and change of ADHD symptoms between 8 and 13 years of age : a longitudinal twin study

• Objective: To study the genetic and environmental contributions to stability and change of attention-deficit/hyperactivity disorder (ADHD) symptoms between 8 and 9 and 13 and 14 years of age.Method: The sample included 1,480 twin pairs born in Sweden between May 1985 and December 1986. At wave 1 in 1994, when twins were 8-9 years old, 1,106 (75%) of the parents responded to a mailed questionnaire, and at wave 2 when the twins were 13-14 years old, 1,063 (73%) responded. A checklist with 14 items based on the 14 DSM-III-R symptoms for ADHD was completed. Structural equation modeling was used to analyze the data.Results: A relatively high stability of ADHD symptoms over this 5-year period was found. This continuity was mainly due to the same genetic effects operating at both points in time. Change in symptoms between childhood and early adolescence was to a large extent due to new genetic effects in early adolescence but also due to new nonshared environmental effects that became important during adolescence.Conclusions: The genetic stability highlights the importance of the continuing search for genes and endophenotypes of ADHD.

Ämnesord

MEDICIN OCH HÄLSOVETENSKAP  -- Klinisk medicin -- Psykiatri (hsv//swe)

MEDICAL AND HEALTH SCIENCES  -- Clinical Medicine -- Psychiatry (hsv//eng)

SAMHÄLLSVETENSKAP  -- Psykologi (hsv//swe)

SOCIAL SCIENCES  -- Psychology (hsv//eng)

MEDICIN OCH HÄLSOVETENSKAP  -- Klinisk medicin -- Pediatrik (hsv//swe)

MEDICAL AND HEALTH SCIENCES  -- Clinical Medicine -- Pediatrics (hsv//eng)

Nyckelord

Attention-deficit/hyperactivity disorder

longitudinal study

stability

change

twin study

Publikations- och innehållstyp

ref (ämneskategori)

art (ämneskategori)