BARCELONA – People diagnosed with type 2 diabetes when they are 18-39 years old have significantly higher cardiometabolic risk burden, compared with older people, according to the results of a large study from the United Kingdom presented at the annual meeting of the European Association for the Study of Diabetes.
Patients in that younger age group were found to have higher glycated hemoglobin (HbA1c) levels, along with higher levels of low-density lipoprotein cholesterol and higher body weight.
“We wanted to evaluate the population-level trend in the incidence of young-onset type 2 diabetes in the United Kingdom, compared with later-onset diabetes,” said senior study authorthe director of the Melbourne EpiCentre at the University of Melbourne at a press briefing during the meeting.
Other aims of the study were to compare temporal trends in the incidence of atherosclerotic cardiovascular disease in younger and older patients with type 2 diabetes, and to see how being “high risk” at diagnosis affected patients’ risk of ASCVD and subsequent risk of death.
High-risk status was defined as having at least two of the risk factors for ASCVD – smoking, high systolic blood pressure, high low-density lipoprotein cholesterol, or chronic kidney disease.
The investigators searched a nationally representative sample of primary care electronic medical records from The Health Improvement Network (THIN) database to find incident cases of type 2 diabetes that occurred between 2000 and 2017, with a total of 370,854 cases identified.
At diagnosis of type 2 diabetes, 8% of the sample (n = 29,678) was aged 18-39 years; 15% (n = 56,798), 40-49 years; 25% (n = 93,698), 50-59 years; 29% (n = 107,261), 60-69 years; and 23% (n = 83,419), 70-79 years. Follow-up was just more than 6 years.
Baseline HbA1c in the respective age groups was 8.6%, 8.4%, 8.1%, 7.8%, and 7.6%, with more than 55% of patients in the two youngest age groups having an HbA1c of 7.5% or higher, compared with 34%-47% in the three oldest age groups.
The percentage of patients with a high LDL cholesterol value (2.6 mmol/L or higher in those without ASCVD, and 1.8 or higher in those with ASCVD) was 71%, 75%, 74%, 69%, and 65%, from the youngest to oldest age groups. A respective 71%, 70%, 66%, 57%, and 44% of the patients had a body mass index of 35 kg/m2 or higher.
Few younger patients had ASCVD at diagnosis (2% of the 18-39 age group; 6% of the 40-49 group), with higher rates in the older age groups (13% of the 50-59 group; 23% of the 60-69 group; and 33% of the 70-79 group).
The percentage of patients considered to be at high risk of ASCVD at diagnosis was 23%, 37%, 45%, 50%, and 53%, respectively, across the five age groups.
Although high systolic blood pressure (SBP; 130 mmHg in those with ASCVD, 140 mmHg in those without) was more common in the older age groups (52% at 50-59 years; 60% at 60-69 years, and 64% at 70-79 years,) a substantial proportion of the younger patients also had a high SBP (27% at 18-39 years and 41% at 40-49 years).
, also of the Melbourne EpiCentre, presented the main findings of the study during the meeting, noting that the proportion of people diagnosed when they were younger than 50 years remained stable between 2000 and 2017, with a marginal increase in those diagnosed when they were aged 50-59 years, and a decline in those diagnosed when they were older than 70 years.
In the youngest and oldest age groups, equal numbers of men and women were diagnosed with type 2 diabetes, and more women than men were diagnosed in the 60-69 age group, Dr. Koye said. However, for the 40-49 and 50-59 age groups, there were more men than women diagnosed with type 2 diabetes.
Patients were followed for an average of just more than 6 years. “The rate of atherosclerotic cardiovascular disease was declining in all age categories during 2000-2006, but after that, we saw a stable and consistent pattern for all age categories after 2007,” Dr. Koye observed.
In regard to all-cause mortality, there was a 30% decline in the oldest age group (70-79 years), and a 20% decline in the 60-69 age group, but there was no significant decline in the younger age groups, he added.
The investigators determined the average time to event (ASCVD or all-cause mortality) by high-risk status at type 2 diabetes diagnosis for each age group. These analyses showed that there was little difference between the high- and low-risk groups for the average time to ASCVD or all-cause mortality in the youngest age group, with wider differences in the older patients of 1-2 years for ASCVD and 0.5-2 years for all-cause mortality.
Dr. Koye noted that people with young-onset type 2 diabetes had a risk of ASCVD or all-cause mortality that was similar to that of older people, irrespective of whether or not they were considered to be at high or low risk of events. “So we need a more focused treatment strategy for the youngest age group, irrespective of the cardiometabolic risk level at diagnosis,” he said.
Dr. Paul and Dr. Koye reported having no conflicts of interest.
SOURCE: Koye D et al. EASD 2019, .