Patients' diagnosis decisions in Alzheimer's disease: the influence of family factors.

It is surprising to observe that the number of patients receiving a late diagnosis for Alzheimer's disease (AD) remains high even in countries promoting early diagnosis campaigns. We explore the impact of family history and family support on the risks of receiving a delayed diagnosis. We use French data of 1131 patients diagnosed between 1991 and 2005. We find that the presence of AD history in the family increased the risks of receiving a delayed diagnosis. This was true especially when AD history involved brothers, sisters and other relatives (uncles or cousins). The presence of an informal caregiver at the time of the first warning signs reduced the risks of receiving a late diagnosis, regardless of the informal caregiver concerned (spouse, son, daughter etc.). We identify several opportunities for early detection campaigns. Families with history of disease should be targeted. Campaigns should also target isolated patients, who do not benefit from informal care. Our results underline the importance of improving the diagnosis access for old patients and for men.