High Blood Sugar at a Young Age May Raise Risk for Cardiovascular Complications
Adult-onset diabetes used to be an “adult” disease. However, as overweight and obesity are more common in adolescents, more are being diagnosed with this chronic condition at a younger age.
A recent study indicates that chronically elevated blood sugar and insulin resistance in this population significantly raise the risk of worsening structural and functional heart damage between the teenage years and young adulthood.
The study was done as a collaboration between the Baylor College of Medicine in the US, the University of Bern in Switzerland, Murdoch Children’s Research Institute in Australia, the Universities of Bristol and Exeter in the UK, and the University of Eastern Finland. The results were published in the highly esteemed Diabetes Care.
In this new study, nearly 1600 adolescents chosen from the University of Bristol’s Children of the 90s cohort were monitored from age 17 to 24 years. To evaluate the prevalence of prediabetes (elevated fasting blood sugar levels), two cutpoints were used: a strict cutpoint of ≥5.6 mmol/L recommended by the American Diabetes Association, and ≥6.1 mmol/L , which is the current recommendation in several countries.
When combined, 6.2% of 17-year adolescents had fasting blood sugars of ≥5.6 mmol/L, which increased almost fivefold to 26.9% by 24 years of age. Only 1.1% adolescents had a level of ≥6.1 mmol/L, but the prevalence increased fivefold to 5.6% by age 24.
Excessive heart enlargement (known as left ventricular hypertrophy) increased threefold from 2.4% at age 17 to 7.1% at age 24, and heart dysfunction went from 9.2% o 15.8% in young adulthood.
Chronically elevated fasting blood glucose levels of ≥5.6 mmol/L from age 17 to 24 years were linked with a 46% higher risk of left ventricular hypertrophy. This risk was threefold if fasting sugar was consistently ≥6.1 mmol/L.
Elevated blood sugar also reduced heart muscle relaxation, changed normal heart function, and significantly raised the pressure of blood flow returning to the heart. Chronic insulin resistance was linked with a 10% higher risk of premature and worsening heart damage. Within the 7-year growth period, increased blood sugar levels added 0.57 g/m to cardiac mass increase in females compared to a 0.11 g/m increase in males.
Past research in adults has shown the elevated blood sugar levels and insulin resistance at a young age greatly predict the risk of type 2 diabetes in individuals in their mid-fifties. In addition, it’s known that when a younger person is diagnosed with type 2 diabetes, more and severe complications may follow quickly.
Previous research hasn’t been conducted to focus on the earliest consequences of elevated blood sugar and insulin resistance on the heart because there are limited repeated echocardiography evaluations in large populations of healthy adolescents.
This new study is the biggest and longest to monitor glucose levels and repeated echocardiography studies in primarily young health populations in the world. The subjects’ fasting blood sugar levels and insulin were measured at ages 17 and 24 years. Echocardiography measurements of the heart function and structure were also completed at these ages.
Fasting glucose and insulin levels were used to evaluate insulin resistance. Blood samples of LDL cholesterol, HDL cholesterol, triglycerides and high-sensitivity C-reactive protein were also consistently measured. Also included in the analysis were blood pressure, heart rate, socio-economic status, family history of cardiovascular disease, smoking status, accelerometer measure of sedentary behavior and exercise as well as dual-energy X-ray absorptiometry measured fat mass and lean mass.
Agbaje, physician and associate professor (docent) of Clinical Epidemiology and Child Health at the University of Eastern Finland noted, “Earlier results from the same cohort indicate that late adolescence is a critical period in the evolution of cardiometabolic diseases. The current findings further confirm that even healthy-looking adolescents and young adults who are mostly normal weight may be on a path towards cardiovascular diseases, if they have high blood glucose and insulin resistance. Surprisingly, we observed that high blood sugar may aggressively damage females’ hearts five times faster than males’; therefore, special attention should be paid to girls in terms of prevention”.
Agbaje, the study’s senior author, concludes, “Worsening insulin resistance and increased fat mass have a bidirectional reinforcing vicious cycle. In the new study, we observed that two-thirds of the effect of insulin resistance on excessive heart enlargement was explained by increased total body fat. The five-fold increase in the prevalence of prediabetes within 7 years of growth from adolescence to young adulthood underscores the critical importance of lifestyle behavior and dietary habits, especially after adolescents have become independent from their family”.
Diabetes prevention in young adults is key. Below are tips to protect them:
· Be a role model. Avoid sugar-sweetened beverages, sports drinks, soda, tea, and energy drinks.
· Encourage physical activity as part of a healthy lifestyle.
· Don’t reward kids with food. This may set up a negative relationship with food and overeating.
· Choose whole grains, which have been shown to reduce the risk of diabetes. 2
· Encourage lean protein sources such as fish, poultry, and low-fat dairy products.
· Serve vegetables at most meals to encourage a plant-forward diet.
· Limit red meat and processed red meat, which have been associated with a higher risk of diabetes, heart disease, and other chronic conditions. 3
· Include low-fat dairy products such as yogurt, which may help prevent diabetes. 4
· Add beans or lentils to their diet for added fiber and a meatless meal option.
· Discourage the intake of fast food and convenience food.
Lisa Andrews, MEd, RD, LD
Reference:
Andrew O. Agbaje; Justin P. Zachariah; Alan R. Barker; Craig A. Williams; Dimitris Vlachopoulos; Christoph Saner; Tomi-Pekka Tuomainen. Persistent Hyperglycemia and Insulin Resistance With the Risk of Worsening Cardiac Damage in Adolescents: A 7-Year Longitudinal Study of the ALSPAC Birth Cohort. Diabetes Care, 2025 DOI: 10.2337/dc24-2459
Dietary fibre and whole grains in diabetes management: Systematic review and meta-analyses - PubMed
