The number of people reaching the age of 85 will increase by 2020, putting extra pressure on health and social services, according to research.
Experts from the universities of Leicester and Newcastle suggested that people may live longer lives but may be affected by several diseases. They said planners need to look ahead to tackle this.
The study of more than 800 85-year-olds found "potential unmet needs" in relation to health and social care.
They discovered that while many of the participants felt in good health and were optimistic, a proportion had undiagnosed health problems.
Everyone in the study lived in Newcastle upon Tyne and North Tyneside and were followed via check-ups and analysis of their medical records.
The study found that 12% of the group were suffering moderate or severe mental decline, while 21% had incontinence.
A total of 60% had hearing problems and 37% had issues with their sight.
Overall, 58% of the group had high blood pressure, 52% had osteoarthritis and 47% had hardening and narrowing of the arteries. Some 47% had cataracts.
The authors concluded: "For planners of services, on the basis of present demographic trends, we can say that in the UK by 2020 the 85-year-old population will increase by 33%, 10% of whom currently require institutional care, 32% of whom have had an outpatient attendance, and 7% an attendance at an accident and emergency department in the past three months.
The research was published online in the British Medical Journal (BMJ).