The leading cause of irreversible blindness and severely impaired eyesight--age related macular degeneration, or AMD for short--is expected to affect 77 million Europeans by 2050, reveal the latest calculations, published online in the British Journal of Ophthalmology.
This will require considerable extra healthcare resource and careful planning for decades to come, particularly as most cases will be in people aged 70+, warn the researchers.
AMD occurs when the small central portion of the retina, the light-sensing tissue at the back of the eye (macula), deteriorates with age. When advanced, it can be treated, but not cured.
To try and come up with an accurate estimate of the likely demands placed on healthcare services by AMD, the researchers calculated the numbers of existing (prevalent) and new (incident) cases across member states of the European Union (EU) up to the year 2050.
To do this, they pooled data from 22 prevalence (existing disease) studies involving 55,323 people, aged, on average, between 60 and 81, and from four incidence (new cases) studies from across Europe.
The resulting analysis showed that the number of existing cases is projected to rise by 15%, while the number of new cases is projected to rise by 75% up to 2050.
By that date, the estimated projections show that one in four older adults in the EU will have AMD, ranging from just under one in 10 of those younger than 65 to just under 27% of those over the age of 75.
And the proportion of those with advanced AMD will be just under 2.5% for all older ages combined, the calculations show.
To calculate the figures for new cases of advanced AMD, the researchers pooled the data for 7223 study participants from the four incidence studies.
They calculated an annual rate of 1.4 new cases of advanced AMD per 1000 people aged 50+, with comparable figures of 0.5/1000 for the under 70s, rising to 6.7/1000 for the over 70s.
Based on these figures, they estimate that 77 million people in the EU will have AMD by 2050, compared with 67 million as of 2015.
The steepest increase will likely be among those aged 75 and older, rising from 50 to 57.6 million (15%), as a result of population ageing, with the proportion of those with advanced AMD expected to rise by 20%, from 10 to 12 million up to 2050.
And the numbers of new cases of advanced AMD will increase from 400,000/year to 700,000 by 2050, with the highest numbers of such cases in Germany.
The researchers caution that most of the included studies came from Western Europe, so the findings may not be applicable to Eastern European countries. And the periods during which new cases were identified varied across the included studies, which may have affected the precision of the estimates they calculated.
Nevertheless, they estimate that both existing and new cases of all stages of AMD will steadily increase in Europe until 2050.
"This will require considerable additional healthcare service and resource allocation, which should be considered already today in all European healthcare systems," they warn.
Peer reviewed? Yes
Evidence type: Systematic review and meta-analysis