Prolonged, Disabling Fatigue in Teens Common, Undertreated

Megan Brooks

May 02, 2013

Extreme, persistent fatigue in US adolescents is common, highly disabling, and often coexists with mood disorders, new research shows.

A survey conducted by investigators from the National Institute of Mental Health showed that prolonged fatigue, defined as lasting 3 months or longer, was reported in 3% of teens aged 13 to 18 years, and more than half of these youth reported severe or very severe difficulties in school, family, or social situations.

Among teens with prolonged fatigue, 1.4% had prolonged fatigue alone, and 1.6% had prolonged fatigue with comorbid depression or anxiety.

"Many parents complain their adolescents are 'lazy' because they tend to sleep late on weekends and do not seem to have much energy. Our data suggest that fatigue may be an indicator of either physical or mental disorders that should be followed up by their physician," Kathleen Merikangas, PhD, from the National Institute of Mental Health, told Medscape Medical News.

The study is published in the May issue of the American Journal of Psychiatry.

The investigators studied the prevalence and correlates of prolonged fatigue in a representative sample of 10,123 US adolescents aged 13 to 18 years. They defined prolonged fatigue as extreme fatigue with at least 1 associated symptom, including pain, dizziness, headache, sleep disturbance, inability to relax, and irritability, that does not resolve by rest or relaxation and lasts at least 3 months.

Dr. Merikangas said what she found most interesting was "the extent to which persistent fatigue alone, without comorbid anxiety or depression, was associated with disability in adolescents from the general population."

Nearly 60% of the adolescents with prolonged fatigue only had severe or very severe disability, and their rates of poor physical and mental health were on par with those of adolescents with mood or anxiety disorders, the investigators say.

Adolescents with prolonged fatigue plus a mood or anxiety disorder had significantly greater disability, poorer mental health, and more health service use than those with either condition alone.

Dr. Kathleen Merikangas

"Extreme fatigue that continues even after rest and interferes with adolescents' ability to participate academically, socially, or at home is a pathological condition, yet it's not being recognized and treated," Dr. Merikangas commented in a statement. "Also, teens with a depressive or anxiety disorder plus persistent fatigue appear to be sicker than those without fatigue."

"Fatigue should be routinely assessed by healthcare providers. Among youth with mood or anxiety disorders, fatigue may be an important indicator of negative health behaviors (eg, smoking, drug use) and disability," she said.

In an accompanying editorial, Gijs Bleijenberg, PhD, and Hans Knoop, PhD, of Radboud University Nijmegan Medical Centre, the Netherlands, write that the prevalence of persistent fatigue without anxiety or depression was "surprisingly high."

Perhaps of even greater concern was that 60% of this group had disabling fatigue, yet most did not seek medical help.

They note that is not unusual for adolescents to engage in extreme behavior and exhaust themselves. However, fatigue that does not resolve when teens modify their behavior has significant health implications for social, emotional, and intellectual development and warrants medical attention.

The research was funded by the National Institute of Mental Health. Dr. Merikangas has disclosed no relevant financial relationships. A complete list of author disclosures is presented with the original article.

Am J Psychiatry. 2013;170:502-510. Abstract, Editorial


Comments on Medscape are moderated and should be professional in tone and on topic. You must declare any conflicts of interest related to your comments and responses. Please see our Commenting Guide for further information. We reserve the right to remove posts at our sole discretion.