10% of Diabetes Cases among Adults aged 50+ are Undiagnosed

Posted on: 13 November 2015

New research shows that 10% of adults aged 50 and over in Ireland, the equivalent to 120,000 older adults, have type 2 diabetes, rising to 16% in those aged 80 and over. The study from the Irish Longitudinal Study on Ageing (TILDA), led by Trinity College Dublin  further reveals that one in ten cases of the disease are undiagnosed in this population. A further 5.5% of the older population have pre-diabetes, placing them at increased risk of developing type 2 diabetes in the future.  The new research   has just been published in the prestigious Diabetes Research and Clinical Practice and was discussed last week at  a  Tilda Conference for better policies for ageing in Ireland.

 Key Findings:

•  1 in 10 of the population aged over 50 in Ireland had diabetes, the equivalent to 120,000 people aged over 50 in Ireland. The majority had their diabetes diagnosed but a substantial proportion of those with diabetes were undiagnosed (1 in 10).
•  The prevalence of pre-diabetes was 5.5%. These people are at increased risk of developing diabetes.
• Type 2 diabetes was more common in men (12%) than women (7%) and increased with age from 5% in 50-59 year olds to 16% in those aged 80+.
• There is a strong relationship between being male and both diabetes and pre-diabetes. A self-reported history of hypertension and being centrally obese also had strong relationships with both diabetes and pre-diabetes.
• There was a strong relationship with increasing age, a self-reported history of high cholesterol, having poor or fair self-rated health and reporting low levels of physical activity with having diabetes.
• Undiagnosed type 2 diabetes was more common outside of Dublin; compared to those living in Dublin city or county, persons living in other urban or rural areas were more likely to have undiagnosed diabetes,
• Private health insurance holders were less likely to have undiagnosed diabetes compared to those with neither public nor private medical costs cover.

This research is unique because it provides the first national prevalence of diagnosed, undiagnosed and pre-diabetes in older Irish adults and shows that our rates of diabetes are similar to those of other European countries.

Type 2 diabetes is a leading cause of death and disability in Ireland and internationally. Diabetes is associated with an increased risk of heart attacks, heart failure, kidney disease and falls, resulting in disability, loss of independence and early mortality. Consequently, diabetes accounts for approximately 10% of Irish healthcare expenditure.

The study also shows that diabetes is more common in men than women. People with diabetes, compared to those without the condition, are more likely to be obese, have low levels of physical activity and suffer from other health conditions such as high cholesterol and high blood pressure.

Speaking about the findings, lead author, Dr. Siobhan Leahy said “These findings confirm for the first time the total burden of type 2 diabetes in older adults in Ireland. While efforts are underway to improve care and access to services for those with diabetes a significant number of older adults with diabetes remain undiagnosed and therefore untreated. Lifestyle factors are clearly associated with diabetes and pre-diabetes and public health campaigns promoting the benefits of a healthy lifestyle may help reduce the future incidence of diabetes in Ireland and lessen complications in those with diagnosed diabetes”

Principal Investigator of the TILDA Study and senior author of the study, Professor Rose Anne Kenny added: “Diabetes and its related complications account for up to 10% of healthcare expenditure annually. Timely diagnosis and treatment of the disease are key to reducing this healthcare burden. However our findings emphasise that there is still a significant proportion of Irish adults with diabetes who remain undiagnosed, and targeted screening may help to reduce this.”

The full paper is available here: http://dx.doi.org/10.1016/j.diabres.2015.10.015

Notes to the Editor:

Diagnosed diabetes

Diagnosed was defined using self-reported doctors’ diagnosis and information about anti-glycaemic medications.

Undiagnosed diabetes and pre-diabetes

Laboratory analysis of blood tested for glycated haemoglobin (HbA1c) was then used to identify undiagnosed and pre-diabetes. Pre-diabetes and undiagnosed diabetes were defined by measurement of glycated haemoglobin (HbA1c) as per American Diabetes Association cut-off values. HbA1c reflects an individual’s average glycaemic control over the previous 8-12 weeks and is an accepted method for the identification of diabetes and pre-diabetes

About TILDA

The Irish Longitudinal Study on Ageing (TILDA) was launched in November 2006 to study a representative cohort of over 8,000 people aged 50 and over and resident in Ireland, charting their health, social and economic circumstances over a 10-year period. It the most comprehensive study of ageing ever carried out in Ireland and is modelled closely on long-running ‘sister’ studies worldwide, such as the US Health and Retirement Survey and the English Longitudinal Study on Ageing. The study is being carried out by Trinity College Dublin in collaboration with an interdisciplinary panel of scientific researchers, with expertise in various fields of ageing from the Economic and Social Research Institute (ESRI), National University of Ireland Galway (NUIG), Royal College of Surgeons in Ireland (RCSI), University College Cork (UCC) and Waterford Institute of Technology (WIT). A group of international scientists advises the TILDA investigators. Funding has been provided by the Department of Health, Irish Life and the Atlantic Philanthropies.