A diagnosis of prediabetes should be a warning for people to make lifestyle changes to prevent both full-blown diabetes and cardiovascular disease (CVD), according to scientists at Wake Forest School of Medicine.
"We know that having diabetes increases the risk of developing
cardiovascular disease, so in our study we wanted to determine what the
absolute risk or probability of developing heart disease was for people
who were only at a pre-diabetic level of blood sugar," said the study's
lead author Michael P. Bancks, Ph.D., assistant professor of
epidemiology and prevention at Wake Forest's medical school, a part of
Wake Forest Baptist Health.
The study is published in the current issue of Diabetes Care.
Prediabetes is indicated by a fasting blood sugar level between100
and 125 mg/dL (5.6 to 6.9 mmol/L), while a fasting blood sugar level of
less than 100 mg/dL (5.6 mmol/L) is considered normal. A level of 126
mg/dL (7 mmol/L) and higher is the diagnostic threshold for diabetes,
In the study, the researchers used data from seven observational
studies that included both white and black men and women who were
followed from 1960 through 2015. Prior research focused on white
Americans of European descent, whereas this study included
African-Americans so the findings could be generalized to a broader
population, Bancks said.
The sample included 19,630 individuals who had not had a prior CVD
event, considered here as heart disease or stroke. Absolute risk of CVD
was determined through analysis of participants' fasting glucose
category beginning at age 55 through 85.
Bancks and colleagues found that the risk for CVD ranged from 15
percent (non-diabetic) to 38 percent (diabetic) among women and from 21
percent (non-diabetic) to 47 percent (diabetic) among men. Increases in
glucose to the diabetic level during mid-life were associated with
substantially higher cardiovascular risk than when glucose levels stayed
below the diabetes threshold.
"Although we found that individuals who had pre-diabetic levels of
blood glucose did not have a higher absolute risk for cardiovascular
disease, we know that most people go on to develop diabetes unless they
take measures to reduce their blood sugar levels," Bancks said.
"Our study provides further evidence that if you can avoid diabetes
you may be able to stave off cardiovascular disease. Pre-diabetes should
serve as a red flag to doctors to closely monitor their patient's blood
sugar to try to prevent diabetes through lifestyle interventions like
better diet and increased physical activity, and if necessary, with