A 45-year-old woman comes to the office due to fatigue, weight gain, and insomnia for the past 2 months. The patient has difficulty falling asleep, awakens at 4:00 AM, and stays awake for the rest of the day. She also describes nonspecific muscle aches and pains in her shoulders, neck, and abdomen. She says, "I was always pretty healthy, but now I worry that something is wrong or that I could have cancer." The patient has stopped exercising due to lack of motivation and has lost nearly all interest in spending time with friends or family. She has a history of hypertension, for which she takes hydrochlorothiazide. Physical examination is normal except that blood pressure is slightly higher than usual at 142/88 mm Hg and there has been a weight gain of 2.7 kg (6 lb). The patient admits that she has been forgetful recently, sometimes neglecting to take her medication. Laboratory evaluation, including thyroid function testing, is within normal range. The patient appears tense and anxious. Which of the following is the most likely diagnosis?
Major depressive disorder | |
Diagnosis |
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This patient's 2-month history of low energy, weight gain, insomnia with early morning awakening, impaired concentration (forgetfulness), and loss of interest is most consistent with major depressive disorder (MDD). Some individuals with MDD do not report feeling depressed due to poor recognition or concerns of stigma and may come to their primary care physicians with excessive worry over physical health, pain symptoms (eg, muscle aches, abdominal cramps, headaches), and other somatic symptoms (eg, fatigue, sleep disturbance, appetite change). When medical illness has been ruled out, MDD should be considered high in the differential diagnosis of patients with these symptoms.
(Choice A) Some signs and symptoms of MDD are identical to those of a general medical condition (eg, weight loss in cancer, fatigue in hypothyroidism). Depressive disorder due to another medical condition is diagnosed when there is evidence from the history, physical examination, or laboratory tests that the symptoms can be entirely explained by the physiologic mechanism of another illness. This patient's unremarkable physical examination and normal laboratory results make MDD more likely.
(Choice B) Patients with MDD can have worry and psychomotor agitation (eg, restlessness, fidgeting); however, generalized anxiety disorder is characterized by multiple worries, not just health anxiety, lasting ≥6 months.
(Choices C and E) Illness anxiety disorder involves an extreme level of worry about having a serious illness, followed by excessive health-related behaviors for ≥6 months. Somatic symptom disorder involves a focus on the seriousness of bodily symptoms with excessive thoughts, anxiety, or energy devoted to them for ≥6 months. Somatic symptoms and related disorders are not diagnosed if they arise only during an acute depressive episode.
Educational objective:
Major depressive disorder can present with loss of interest or pleasure without depressed mood. Patients may seek treatment in the primary care setting for somatic symptoms such as fatigue, sleep disturbance, and pain.