Sleep and body mass index in depressed children and healthy controls
Received 24 November 2008; received in revised form 22 January 2009; accepted 2 February 2009.
Abstract
Objective
Higher body mass index (BMI) has been associated with more sleep disturbance and depressive symptoms, but the combined effects of depression and BMI on sleep have not been studied in children. This study evaluated the relationship between BMI and polysomnography in children with major depressive disorder (MDD), compared to healthy controls (HCs).
Method
The sample of 104 subjects included 72 children, 8–17years old, with MDD and 32 similarly aged HCs with no personal or family history of psychopathology. BMI was adjusted using the CDC formula for percentiles by age. Subjects were categorized as (1) normal weight (5–84th percentile) or (2) high weight, which included at risk of overweight and overweight (⩾85th percentile). All analyses were adjusted for sex and Tanner maturational stage scores.
Results
In the MDD group only, higher BMI was significantly correlated with decreased sleep efficiency, decreased percentage of rapid eye movement sleep (REM%), and higher percentage of time spent awake and moving (TSPAM). In the HC group only, higher BMI correlated with higher total sleep time. Multivariate analyses revealed significant interactions between the BMI and diagnostic groups for several REM sleep parameters, such that high-weight children from the HC and MDD groups had increases and decreases in REM sleep, respectively. TSPAM increased in the high-weight MDD group, but decreased in the high-weight HC group.
Conclusions
Although limited by small sample size, these findings suggest that children and adolescents with MDD and a high BMI have more fragmented sleep than other children. The increased REM sleep patterns observed with MDD in this and other studies normalized in high-weight children with MDD. Prevention and treatment strategies should target both sleep and weight as factors that can potentially influence the development and course of MDD.
aUniversity of Michigan, Department of Psychiatry, Ann Arbor, MI, United States
bMedical University of Warsaw, Department of Psychiatry, Warsaw, Poland
cUniversity of Texas Southwestern Medical Center at Dallas, Dallas, TX, United States
Corresponding author. Address: University of Michigan, Department of Psychiatry, 4250 Plymouth Road, SPC 5740, Ann Arbor, MI 48109-2700, United States. Tel.: +1 734 232 0294; fax: +1 734 998 7992.
ABSTRACT