A 12-year study involving 1,221 married couples ages 65 or older (part of the Cache County (Utah) Memory Study) has revealed that husbands or wives who care for spouses with dementia are six times more likely to develop Alzheimer’s themselves than those whose spouses don't have it. The increased risk is of comparable size to having the ‘Alzheimer's gene’. The researchers speculate that the great stress of caregiving might be responsible for the increased dementia risk, emphasizing the need for greater caregiver support.
 Greater Risk of Dementia When Spouse Has Dementia? The Cache County Study. Journal of the American Geriatrics Society [Internet]. 2010 ;58(5):895 - 900. Available from: http://dx.doi.org/10.1111/j.1532-5415.2010.02806.x