The factors most commonly linked with OA are age, female, obesity, trauma, and loose joints. Postmenopausal women who are overweight and smoke may be at greatest risk.

Some studies show life expectancy decreases when the person has OA. OA in the finger joints is especially likely to predict a decrease in the number of years a person lives. The reason for this is unknown.

Genetics and heredity may also play a key role in OA. More study is needed to find the exact gene or genetic link between OA and death. Until then we can't say for sure your aunts' age at death was directly linked to their OA.