A new study led by researchers in the Divison of Geriatrics of the David Geffen School of Medicine at the University of California, Los Angeles, found that cognitive decline in women occurs earlier than previous research has indicated.
The researchers examined data on more than 2,000 healthy women enrolled in the Study of Women’s Health Across the Nation (SWAN). The women were in their 40s when they enrolled in the study in 1996 and were tested every one to two years over the next decade.
The data shows that women’s average decline in mental processing ability was 5 percent during the decade-long period. Cognitive processing speed, which includes speed of perception and reaction, showed an average decline of around 1 percent every two years and verbal memory declined on average around 1 percent every five years.
The authors conclude that women in their 40s and 50s who find they are forgetting things more often or think they are slower to react may only be experiencing usual aging, analogous to gradual slowing of physical reaction time, running speed, metabolic rate, and other declines common in midlife.
The study, “Evidence for Cognitive Aging in Midlife Women: Study of Women’s Health Across the Nation,” was published on the website of PLOS One. It may be found here.