(HealthDay News) — Older individuals who develop cancer have better memory and slower memory decline than those who remain cancer-free, according to a study published online June 21 in JAMA Network Open.
Monica Ospina-Romero, M.D., from the University of California in San Francisco, and colleagues compared long-term memory trajectories in patients before and after they developed incident cancer to those of similarly aged individuals not diagnosed with cancer. Data were included for 14,583 U.S. adults born before 1949 with no cancer history.
The researchers found that 2,250 participants had a cancer diagnosis and 12,333 had no cancer diagnosis during a mean follow-up of 11.5 years. In the decade before a cancer diagnosis, the rate of memory decline was 10.5 percent (95 percent confidence interval [CI], 6.2 to 14.9 percent), which was slower than memory decline in similarly aged individuals without cancer diagnosis. The mean memory function immediately before diagnosis was 0.096 standard deviation (SD) units (95 percent CI, 0.060 to 0.133 SD units) higher for individuals diagnosed at 75 years of age versus similarly aged cancer-free individuals. Compared with memory before diagnosis, a new cancer diagnosis correlated with a short-term memory decline of −0.058 SD units (95 percent CI, −0.084 to −0.032 SD units). The rate of memory decline was 3.9 percent (95 percent CI, 0.9 to 6.9 percent) slower after diagnosis in individuals with versus without a cancer diagnosis.
“These novel findings support the possibility of a common pathologic process working in opposite directions in cancer and Alzheimer disease,” the authors write. “Identification of a potential association between carcinogenesis and neurodegeneration may open a new avenue in research for prevention and treatment of Alzheimer disease.”