Three-year latent class trajectories of attention-deficit/hyperactivity disorder (ADHD) symptoms in a clinical sample not selected for ADHD

L Eugene Arnold; Stephen J Ganocy; Katherine Mount; Eric A Youngstrom; Thomas Frazier; Mary Fristad; Sarah M Horwitz; Boris Birmaher; Robert Findling; Robert A Kowatch; Christine Demeter; David Axelson; Mary Kay Gill; Linda Marsh

doi:10.1016/j.jaac.2014.03.007

Three-year latent class trajectories of attention-deficit/hyperactivity disorder (ADHD) symptoms in a clinical sample not selected for ADHD

J Am Acad Child Adolesc Psychiatry. 2014 Jul;53(7):745-60. doi: 10.1016/j.jaac.2014.03.007. Epub 2014 Apr 30.

Authors

Affiliations

¹ The Ohio State University, Columbus, OH. Electronic address: l.arnold@osumc.edu.
² Case Western Reserve University, Cleveland.
³ The Ohio State University, Columbus, OH.
⁴ University of North Carolina at Chapel Hill, NC.
⁵ Center for Pediatric Behavioral Health and Center for Autism at the Cleveland Clinic, Cleveland.
⁶ New York University Langone Medical Center, New York.
⁷ Western Psychiatric Institute and Clinic, University of Pittsburgh Medical Center, Pittsburgh.
⁸ Johns Hopkins University and the Kennedy Krieger Institute, Baltimore.
⁹ The Ohio State University and Nationwide Children's Hospital.

Abstract

Objective: This study aims to examine trajectories of attention-deficit/hyperactivity disorder (ADHD) symptoms in the Longitudinal Assessment of Manic Symptoms (LAMS) sample.

Method: The LAMS study assessed 684 children aged 6 to 12 years with the Kiddie-Schedule for Affective Disorders and Schizophrenia (K-SADS) and rating scales semi-annually for 3 years. Although they were selected for elevated manic symptoms, 526 children had baseline ADHD diagnoses. With growth mixture modeling (GMM), we separately analyzed inattentive and hyperactive/impulsive symptoms, covarying baseline age. Multiple standard methods determined optimal fit. The χ(2) and Kruskal-Wallis analysis of variance compared resulting latent classes/trajectories on clinical characteristics and medication.

Results: Three latent class trajectories best described inattentive symptoms, and 4 classes best described hyperactive/impulsive symptoms. Inattentive trajectories maintained their relative position over time. Hyperactive/impulsive symptoms had 2 consistent trajectories (least and most severe). A third trajectory (4.5%) started mild, then escalated; and a fourth (14%) started severe but improved dramatically. The improving trajectory was associated with the highest rate of ADHD and lowest rate of bipolar diagnoses. Three-fourths of the mildest inattention class were also in the mildest hyperactive/impulsive class; 72% of the severest inattentive class were in the severest hyperactive/impulsive class, but the severest inattention class also included 62% of the improving hyperactive-impulsive class.

Conclusion: An ADHD rather than bipolar diagnosis prognosticates a better course of hyperactive/impulsive, but not inattentive, symptoms. High overlap of relative severity between inattention and hyperactivity/impulsivity confirms the link between these symptom clusters. Hyperactive/impulsive symptoms wane more over time. Group means are insufficient to understand individual ADHD prognosis. A small subgroup deteriorates over time in hyperactivity/impulsivity and needs better treatments than currently provided.

Keywords: ADHD; GMM; hyperactivity/impulsivity; inattention; longitudinal symptoms.

Publication types

Research Support, N.I.H., Extramural
Research Support, Non-U.S. Gov't

MeSH terms

Attention Deficit Disorder with Hyperactivity / classification
Attention Deficit Disorder with Hyperactivity / diagnosis*
Attention Deficit Disorder with Hyperactivity / epidemiology
Bipolar Disorder / diagnosis*
Bipolar Disorder / epidemiology
Child
Comorbidity
Disease Progression
Female
Humans
Longitudinal Studies
Male
Prognosis
Time Factors

Abstract

Publication types

MeSH terms

Grants and funding