All-Ireland study: Almost 210,000 adults in Ireland have diabetes, according to the most accurate figures for the disease ever produced here.
Diabetes is slightly more common in Northern Ireland (5.4 per cent of the population) than in the Republic (4.7 per cent), while in both parts of the island, diabetes is more common among adult females than adult males.
The first comprehensive estimate of the prevalence of diabetes was published yesterday by the All Ireland Population Health Observatory of the Institute of Public Health (IPH). The study was overseen by the Irish Diabetes Prevalence Working Group, representing charities, professional organisations and government agencies on the island.
Using a model designed to estimate the total number of people with diabetes (both diagnosed and undiagnosed) at a local level in the population, the researchers found that in Northern Ireland, just under a quarter of all diabetes cases among those aged 17 years and over are undiagnosed. Because of inadequate primary care data, it was not possible to calculate a similar figure for the Republic.
In 2005, of the 67,063 adults in Northern Ireland with the disease, the prevalence increased with age, with 14 per cent of people aged over 60 having diabetes. Among the 141,063 adults with diabetes in the Republic, a similar trend was seen with a disease prevalence of 13.8 per cent of those aged 60 and over.
The Asian population is the ethnic group most at risk of developing diabetes in the North. Prevalence estimates for ethnic minorities were not available for the Republic due to a lack of data.
Diabetes causes sugar levels in the blood to rise above normal levels. Left untreated, the disease causes damage to the cardiovascular system, the eyes and the kidneys. Diabetes is caused by a lack of the hormone insulin, which regulates blood sugar levels.
There are two types of diabetes: type 1, which occurs in younger people, is the result of the pancreas gland producing no insulin and requires regular insulin injections for treatment; type 2 is more common in older people and results from the cells in the body becoming resistant to insulin. It usually responds to diet and oral medication.
Type 2 diabetes is associated with being overweight and obese. Because of rising obesity levels, the prevalence of type 2 diabetes is expected to rise sharply in the years ahead.
Asked why the prevalence of diabetes was slightly lower in the Republic compared with Northern Ireland, the associate director of the IPH, Dr Kevin Balanda, said the finding was partly due to the slightly younger population in the Republic. The lack of ethnic data was also a factor.
"We now have a reliable method of calculating the number of people on the island with diabetes," Dr Balanda said.
"If we had decent national diabetes registers, we could get a good idea of the number of people at local level who were not diagnosed or treated, which would help GPs in prevention and case finding.
"There is no doubt that the number of people with diabetes on the island is on the increase because our population is growing, it is ageing and obesity rates are rising," he said.
Among the report's recommendations is the establishment of diabetes registers in both jurisdictions to allow for socioeconomic variations in diabetes prevalence to be assessed. It also calls for a comprehensive all-Ireland system for monitoring the prevalence of obesity.
Kieran O'Leary, chief executive of the Diabetes Federation of Ireland, said: "While we welcome the report as a first step we strongly support the need for a national diabetes register."