Ruling out alternative diagnoses. In assessing potentially depressed teenagers like Jane, ruling out conditions with similar symptoms is essential. Medical conditions to be considered in the differential diagnosis are anemia, malignancies, hypothyroidism, and mononucleosis—as well as other viral conditions. There is, however, no evidence to support routine lab testing (including for hypothyroidism) of adolescent patients. Laboratory and other diagnostic evaluation should, instead, be guided by history and targeted physical exam. TABLE 2 presents common medical causes of symptoms of depression that must be considered in the differential diagnosis.
Consider bipolar disorder. Depressive symptoms may also be part of a cycling mood disorder, such as bipolar disorder. In fact, most teens with bipolar disorder will first present with depressive symptoms. Adolescents with depression as part of a bipolar disorder are more likely to have adverse effects with antidepressants than are teens with depression alone. In order to adequately rule out bipolar depression, ask about:
- rapid onset of depressive symptoms: “She just woke up one day and couldn’t stop crying,” for instance
- psychotic symptoms
- family history of bipolar disorder, especially in first-degree relatives
- previous symptoms of mania while on antidepressant treatment (eg, hyperactive, rapid speech, decreased need for sleep).
If a patient has these symptoms or a history of bipolar disorder, refer her or him for a mental health consultation before starting antidepressant treatment.
TABLE 2
Is a medical cause to blame for those symptoms of depression?
| MEDICAL CAUSES | SYMPTOMS | INVESTIGATIONS |
|---|---|---|
| Hyper- or hypothyroidism | Insomnia, agitation, weight loss or gain | Thyroid function tests |
| Anemia | Fatigue, hypersomnia | Complete blood count |
| Sleep disorder | Fatigue, insomnia | Sleep assessment |
| Mononucleosis/viral infections | Fatigue, hypersomnia | EBV test |
| Medications | ||
| Steroids | • Low mood, weight gain, increased appetite | Complete history of medication use (temporal relationship to onset of symptoms) Medication re-challenge test |
| Albuterol sulfate (Ventolin) | • Irritability, insomnia | |
| Isotretinoin (Accutane) | • Low mood, suicidality |
Help in classifying the severity of depression
The severity of depression can vary considerably from one patient to another, and distinguishing mild, moderate, and severe depression has significant implications for treatment. Guidelines for grading depression severity are given in TABLE 3 . A common way to classify the severity of a depressive episode is to count the number of symptoms the teenager is displaying.7 If all 9 symptoms in the DSM-IV-TR criteria are present, the depression would be classified as severe. But even with fewer symptoms, depression should be considered severe if the teenager is suicidal (has a specific suicide plan, a clear intent, or has made a recent attempt); has psychotic symptoms; or functioning is severely impaired (eg, patient is unable to go to school). The Diagnostic and Statistical Manual of Mental Disorders: Primary Care Version (DSM-PC) is also a useful resource for distinguishing between transient depressive responses and depressive disorders.
TABLE 3
Grading the severity of depressive episodes
| In both the Diagnostic and Statistical Manual of Mental Disorders (DSM-IV-TR) and the International Statistical Classification of Diseases and Related Health Problems, 10th Revision (ICD-10), severity of depressive episodes is based on the number, type, and severity of symptoms, as well as the degree of functional impairment. The DSM-IV-TR guidelines are summarized in the table below. | |||
|---|---|---|---|
| DSM-IV-TR GUIDELINES FOR GRADING DEPRESSION SEVERITY | |||
| MILD | MODERATE | SEVERE | |
| Number of symptoms | 5-6 | * | Most† |
| Severity of symptoms | Mild | * | Severe |
| Degree of functional impairment | Mild impairment or normal functioning but with “substantial and unusual” effort | * | “Clear-cut, observable disability” |
Ask yourself: Is this teenager impaired?
Symptoms, in themselves, are not enough to clinch the diagnosis. The fundamental question is whether the symptoms prevent your patient from normal functioning. To judge the extent of a patient’s impairment, you need to assess overall functioning and ask about school, home, friends, and leisure activities. Impairment can be determined by asking the patient and parents the simple questions that every family physician is familiar with:
- How is Jane doing in school? Have her grades slipped lately?
- How is life at home? Does Jane’s mood affect family relationships?
- Does Jane have good friends she can talk to?
- Has her mood affected her ability to maintain friendships?
- What does Jane do for fun? Has she been doing those things lately?
First and foremost, keep your patient safe. Even if you can’t do a complete assessment, your evaluation must at least include the determination of acute risk of harm, either from self-inflicted injury or from impaired judgment. At minimum, assess for suicidality, self-injurious behavior, altered sensorium, substance use, and access to firearms.7 Again, this can be aided by the teen’s answers to symptom checklists.
GLAD-PC Recommendation III: Family physicians should assess for depressive symptoms based on diagnostic criteria established in the DSM-IV or International Statistical Classification of Diseases and Related Health Problems, 10th Revision (ICD-10) (SOR: B, epidemiological studies) and should use standardized depression tools to aid in the assessment (SOR: A, RCTs).
GLAD-PC Recommendation IV: Assessment for depression should include direct interviews with the patients and families/care-givers separately (SOR: B, cohort studies) and should include the assessment of functional impairment in different domains (SOR: C, expert opinion) and other existing psychiatric conditions (SOR: B, cohort studies).