A new risk score can predict which people may develop dementia, based on factors virtually the same as those already known to cause heart disease: obesity, high blood pressure and high cholesterol.

Dementia is a general term to describe the progressive decline in cognitive function due to damage or disease in the brain beyond what might be expected from normal aging. Like fever, dementia can have a variety of causes.

It can interfere with memory, attention, language and problem-solving abilities. In the later stages of the condition, affected persons may lose track of time and place, and may not even know who they are.

Scientists were able to develop the score-based system after analyzing data from the Cardiovascular Risk Factors, Aging and Dementia study, involving 1,500 middle-aged people from Finland. The test subjects were followed to see whether they developed signs of dementia after 20 years.

The new test has an accuracy level of 70 percent in identifying individuals most at risk for developing dementia within 20 years. However, lifestyle changes could alter those outcomes.

Up to now, the only way to identify those at risk has been a genetic test that identifies only one rare form of dementia. Although blood pressure and exercise levels previously have been linked to Alzheimer's, the most common cause of dementia, no other assessment has combined all of the factors included in the new questionnaire.

Dementia is rarely reversible, but health experts believe that some cases may be preventable. Obesity, hypertension and high cholesterol double the risk of developing dementia. People who scored the lowest on the new test had a 1 percent risk level, while those who scored highest had a 16 percent risk.

Scientists believe that the test provides a basis for awakening people to their health risk and encouraging lifestyle changes such as consuming a healthier diet.

Key guidelines include keeping saturated fat and salt consumption low, and favoring foods that are rich in vitamin B, omega 3 fatty acids and zinc. Good food choices are fish, white meat, brown rice, vegetables, fruit and eggs.