Both Malcolm Young, guitarist with the band AC/DC, and David Cassidy, 1970s teen musical sensation, have been in the news lately due to their young onset dementia. Young, 64, died Nov.18, and Cassidy, 67, died Nov. 21.

What types of dementia occur in people under 65? Most typically, these are Alzheimer’s and frontotemporal dementia. Young onset is far more typical in frontotemporal dementia than in Alzheimer’s. Younger adults also are more likely to have a rare form of dementia. People can be in their 30s when symptoms are first noticed but more likely would be 50-65 years old.

Young onset dementia usually progresses more quickly than types of dementia first seen after 65. For instance, Malcom Young is said to have had dementia for only three years. However, at the time of diagnosis, the person and their family often can look back and recognize early signs began some years ago.

To learn more about the differences between dementia and forgetfulness, download our single page guide, “Does my loved one have dementia, or is it normal age-related forgetfulness?”

We are grateful for the music and talent Malcolm Young and David Cassidy shared with their devoted fans and the rest of the world. Our thoughts are with their families and friends.