Prospective, longitudinal study of tic, obsessive-compulsive, and attention-deficit/hyperactivity disorders in an epidemiological sample

Objective: Understanding the interrelatedness of ties, obsessive-compulsive disorder (OCD), and attention-deficit, hyperactivity disorder (ADHD) has b een complicated by studying only cross-sectional samples of clinically refe rred subjects. The authors report the cross-sectional and longitudinal asso ciations of these disorders in an epidemiological sample of children follow ed prospectively into early adulthood. Method: Structured diagnostic interv iew information was acquired on 976 children, aged 1 to 10 years, who were randomly selected from families living in upstate New York in 1975. Reasses sments were acquired in 776 of these subjects 8, 10, and 15 years later. Di agnostic prevalences were estimated at each time point. The associations am ong ties, OCD, and ADHD were assessed within and across time points, as wer e their associations with comorbid illnesses and demographic risk factors. Results: In temporal cross-section, ties and ADHD symptoms were associated with OCD symptoms in late adolescence and early adulthood after demographic features and comorbid psychiatric symptoms were controlled. In prospective analyses, ties in childhood and early adolescence predicted an increase in OCD symptoms in late adolescence and early adulthood. ADHD symptoms in ado lescence predicted more OCD symptoms in early adulthood, and OCD in adolesc ence predicted more ADHD symptoms in adulthood. The associations of ties wi th ADHD were unimpressive in temporal cross-section and were not significan t in prospective analyses. Ties, OCD, and ADHD shared numerous complex asso ciations with demographic and psychopathological risk factors. ADHD was ass ociated with lower IQ and lower social status, whereas OCD was associated w ith higher IQ. Conclusions: Ties and OCD were significantly associated in t his sample, as were OCD and ADHD. These findings are in general consistent with those from family studies, and they help to define the natural history , comorbid illnesses, and interrelatedness of these conditions.