08/20/2026
Same intensity, different engine. Bipolar disorder affects about 2.8% of U.S. adults; borderline personality disorder about 1.4%—and they’re often confused. In bipolar, mood shifts come in episodes that last days to weeks and change sleep, energy, and activity. In borderline, shifts are faster, often tied to relationships and stress, with patterns of sensitivity and impulsivity. If this sounds familiar, a careful evaluation can sort out what’s happening and point to treatment that fits.