Conclusion
Cognitive abilities, particularly those involving speed and problem solving, decline as part of normal aging, although many older adults retain high levels of cognitive function.
These changes do not inevitably lead to dementia.

Assessment of premorbid ability is important in determining whether there has been abnormal cognitive decline and cognitive screening may also be helpful. Patients should be encouraged to have an active lifestyle and reduce cardiovascular risk factors in order to reduce the risk of cognitive decline.

Summary of important points
• In normal aging there is nonpathological cognitive decline.
• Memory complaints are common in later life. Depending on presentation they may indicate normal aging, depression or impending cognitive decline.
• Risk factors for cognitive aging include age, low education,  the APOE genotype and risk factors for cardiovascular disease.

Conflict of interest: None.

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Kaarin J Anstey,
BA (Hons), PhD, is NHMRC Career Development Fellow in Population Health, Director, Ageing Research Unit, Centre for Mental Health Research, Australian National University, and a psychologist, Canberra, Australian Capital Territory.

Lee-Fay Low,
BSc (Hons), is a PhD candidate, Centre for Mental Health Research, Australian National University, and a psychologist, Canberra, Australian Capital Territory.
Reprinted from Australian Family Physician Vol. 33, No. 10, October 2004