â– LECTURE OVERVIEW: Major Depressive Disorder (MDD) is a common, debilitating mood disorder diagnosed biochemically by meeting specific clinical criteria outlined in the DSM-5.
â– THE SIGECAPS CRITERIA:
1. Diagnostic threshold: Requires at least 5 of 9 symptoms present during the same 2-week period, representing a change from previous functioning, where at least one symptom must be depressed mood or anhedonia (loss of interest/pleasure).
2. The mnemonic:
- S - Sleep disturbances (insomnia or hypersomnia).
- I - Interest loss (profound anhedonia).
- G - Guilt or feelings of worthlessness.
- E - Energy depletion or fatigue.
- C - Concentration difficulties or indecisiveness.
- A - Appetite and weight changes (increase or decrease).
- P - Psychomotor agitation or retardation.
- S - Suicidal ideation or recurrent thoughts of death.
â– SPECIAL CLINICAL POPULATIONS & METABOLIC DEVIATIONS:
Infants display higher body water ratios and immature renal filtration capacity, whereas geriatric cohorts exhibit reduced physiologic reserves, progressive heart/renal decline, and polypharmacy interactions.
â– GERIATRIC PHYSIOLOGIC ADJUSTMENTS:
Older patients display reduced physiological reserves, altered muscle-to-fat distributions, and distinct renal filtration profiles.
[HY-BOARD-1134]
🌟 Dynamic Clinical Key:
First-line pharmacological treatment is selective serotonin reuptake inhibitors (SSRIs; e.g., Sertraline, Escitalopram). Sexual dysfunction and weight gain are the most common reasons for treatment non-adherence and discontinuation. Adjust weight-based dosing for pediatric cohorts and use the 'start low and go slow' approach for seniors. Always adjust therapeutic doses based on age-related glomerular filtration clearance.