So far, two local studies have examined the age of onset of dementia in Hong Kong. According to a retrospective case notes review of 454 consecutive people with dementia and mild cognitive impairment at Princess Margaret Hospital in Hong Kong from 1999 to 2004, the average age of dementia onset was 76.7 ± 8.7. The median duration from the symptom onset to medical consultation was 2 years (range from 4 months to 10 years) with a mean of 14.8 months (Sheng, Law, & Yeung, 2009). Another earlier study found that the age of onset of Alzheimer’s disease was related to the frequency of Apolipoprotein E epsilon 4 allele (ApoE) among 65 people with dementia. The mean age of onset identified was 73.7 (Mak et al., 1996).

References:

Mak, Y., Chiu, H., Woo, J., Kay, R., Chan, Y., Hui, E., et al. (1996). Apolipoprotein E genotype and Alzheimer’s disease in Hong Kong elderly Chinese. Neurology, 46(1), 146-149. https://doi.org/10.1212/wnl.46.1.146

Sheng, B., Law, C. B., & Yeung, K. M. (2009). Characteristics and diagnostic profile of patients seeking dementia care in a memory clinic in Hong Kong. International psychogeriatrics, 21(2), 392-400. https://doi.org/10.1017/S104161020800817X