Chapter 18 Depression (Unipolar)
INTRODUCTION
Description: Depression is a biochemically mediated state in which anger, frustration, loss of pleasure, and withdrawal predominate. This must be separated from normal stress reactions and grief.
Prevalence: Twenty million American adults per year, one in six to eight lifetime risk, 6% to 14% of primary care visits, 2 : 1 female to male ratio (1 : 1 after age 55). Depression is the fourth most common reason to seek medical care.
ETIOLOGY AND PATHOGENESIS
Causes: Proposed—alteration in norepinephrine or serotonin through impaired synthesis of neurotransmitters, increased breakdown or metabolism of neurotransmitters, increased uptake of neurotransmitters.
Risk Factors: Strong family history (depression, suicide, alcoholism, substance abuse). Women are at greatest risk during adolescence (up to 60% meet criteria), the premenstrual period, pregnancy, the postpartum period, perimenopause, after pregnancy loss (three times risk) and with infertility (two times risk). Women are especially vulnerable to depression after giving birth.
CLINICAL CHARACTERISTICS
(Hallucinations and delusions may appear in profound cases.)