A recent study has revealed that Alzheimer's disease comes in three types, suggesting that each variation would need to be treated differently.
The UCLA finding could lead to more highly targeted research and, eventually, new treatments for the debilitating neurological disorder, which robs people of their memories.
The study further found that one of the three variations, the cortical subtype, appears to be fundamentally a different condition than the other two, said author Dale Bredesen.
Because the presentation varies from person to person, there has been suspicion for years that Alzheimer's represents more than one illness, said Bredesen, adding that when laboratory tests go beyond the usual tests, they find these three distinct subtypes.
He added that the important implications of this are that the optimal treatment may be different for each group, there may be different causes, and, for future clinical trials, it may be helpful to study specific groups separately.
The subtypes are "inflammatory," in which markers such as C-reactive protein and serum albumin to globulin ratios are increased, "non-inflammatory," in which these markers are not increased but other metabolic abnormalities are present, and "cortical," which affects relatively young individuals and appears more widely distributed across the brain than the other subtypes of Alzheimer's.
No effective therapy for Alzheimer's exists. And scientists have yet to completely identify the cause, although multiple studies have pointed to metabolic abnormalities such as insulin resistance, hormonal deficiencies and hyperhomocysteinemia, a condition characterized by an abnormally high level of an amino acid in the blood.
The findings appear in the current issue of the peer-reviewed journal Aging.