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Why Are We Waiting To Treat Diabetes Until A1c Reaches 6.5%?

Jan 6, 2018

Getting type 2 diabetes at an early age increases risk for all diabetes complications, including death.

Going back years, the diagnosis of diabetes was a fasting plasma glucose (FPG) of 180 mg/dl. Today, it’s an FPG of 126 mg/dl or greater, or an A1C of 6.5% or greater. But should the diagnostic standard move even further, to 100 mg/dl, a lower A1C, and treatment for diabetes start much earlier?


(Chart: ADA 2018 Standards of Care)

To examine the association between early onset of type 2 diabetes mellitus (DM) and clinical  behavioral risk factors for later complications of diabetes, 5,115 people with type 2 were enrolled in a cross-sectional study. Risk factors at time of diagnosis among those diagnosed at ≤45 years (early onset) with diagnosis age 46 to 55, 56 to 65 (average onset = reference), 66 to 75, and >75 years (late onset) were recorded.

According to the analysis, being diagnosed with type 2 diabetes at a young age comes with more serious complications and higher rates of death than being diagnosed later in life.

We know that it takes many years to develop complications in diabetes and having type 2 at a younger age equates to a higher lifetime risk of complications given the projected length of exposure to high glucose and other risk factors. This includes higher death rates, which rose to six times higher when subjects were in early middle age.

Those diagnosed between ages 15 and 30 had more severe nerve damage and signs of early kidney disease than those who had lived with the disease for a similar amount of time but were diagnosed between ages 40 and 50, researchers found. The younger group also had much higher risk of death than peers without diabetes.

We can look at poor glucose control, i.e., HbA1c ≥ 8.0% in the early-, average-, and late-onset groups as the main cause for poorer outcomes. People first diagnosed in middle age had death rates comparable to the general population in their own age group, in contrast. Elevated glucose in an older person may not add all that much in terms of long-term risk, over and above the impact of age itself. It makes sense that the longer you live with elevated blood glucose, the greater the risk for complications and death.

In another study, researchers analyzed data for 354 patients diagnosed with type 2 diabetes in adolescence and early adulthood, and 1,062 patients with more typical onset between ages 40 and 50. The study team used the Royal Prince Alfred Hospital Diabetes electronic database linked to the Australian National Death Index to track complications and deaths related to diabetes.

Patients diagnosed at a young age were matched to patients diagnosed at an older age who had had diabetes for a similar length of time. Both groups tended to have similar rates of metabolic syndrome. They all had abdominal obesity, high cholesterol, and high blood pressure that raised the risk of heart disease. But those diagnosed at an older age were more likely to have been treated for their high blood pressure and cholesterol.

Those diagnosed at a younger age had more severe albuminuria, high levels of protein in the urine that are an early sign of diabetic kidney disease, according to the U.S. National Kidney Foundation. The younger people also had more severe nerve damage than those diagnosed at an older age, the researchers reported in Diabetes Care.

On average, the patients were followed for 10 years until death or the end of the study. The overall risk of death was lower for those diagnosed younger, but diabetes had a stronger effect on that risk for the younger group. Relative to the general population in their own age group, the people diagnosed with type 2 diabetes young had more than three times higher death rates. That rose to six times higher when they were in early middle age.

People first diagnosed in middle age had death rates comparable to the general population in their own age group, in contrast. The impact of type 2 diabetes on younger people should not be underestimated.

The hope is that this type of research will serve to highlight that type 2 diabetes in the young is a serious condition that should be recognized by treating clinicians as such and managed accordingly. Doctors   should give more than just lifestyle advice to young people with type 2 diabetes and even those with prediabetes.

Extrapolating from studies in older type 2 diabetes, excellent metabolic control and aggressive vascular risk factor management early in the course of diabetes should be the norm.

Early onset T2DM is an increasingly common problem, which leads to the premature development of microvascular and macrovascular complications. Although we do not yet have a full understanding of the natural history of this condition, the impact on the individual, service delivery, and finances will be substantial. Those with early onset T2DM represent a high risk group with specific issues and needs. They merit an aggressive and supportive management in a multidisciplinary setting to prevent the development of significant morbidity during their most productive years. Continuing to tackle childhood obesity, one of the main modifiable risk factors for diabetes, should also be a priority for preventing diabetes and applied earlier in life, rather than waiting to be diagnosed with an A1c of 6.5% or a fasting blood sugar of 125mf/dL.

Practice Pearls:

  • Younger adults with type 2 diabetes are more likely to have cardiovascular disease (CVD) risk factors — such as severe obesity, hyperlipidemia, low-grade inflammation, physical inactivity, and smoking — compared with adults who developed diabetes later in life.
  • Physicians may underestimate the risk in early onset T2DM, which is further reflected in the consistent undertreatment of both hypertension and hyperlipidemia in both pediatric and young adult groups.
  • By the fourth decade, those with early onset T2DM in the UK (mean age 34 years) have a cardiovascular risk profile (overweight, hyperlipidemia, hypertension) similar to that of an older adult with T2DM (mean age 67 years).


Benhalima et al. 2011; Shield et al. 2009: Gunathilake et al. 2010 ; Diabetes Care, online March 16, 2016.

Diabetes/Metabolism Research and Reviews. Dec 11, 2017