A recent study found that millions of diabetes cases are possibly being missed under the current US screening guidelines, especially among Asian Americans, with the researchers suggesting that a better way to test for the condition would be to omit body weight from the equations.
Current guidelines from the US Preventive Services Task Force recommend screening adults aged between 35 and 70 who are considered overweight or obese (with a body mass index over 25).
However, racial and ethnic minority groups, especially Asian people, tend to develop diabetes at lower BMIs, so to identify more people with the condition across groups, all adults aged 35-70, regardless of their weight, should be screened, said the team, whose study was published in the American Journal of Preventive Medicine.
“It’s a strategy that’s most likely to promote health equity,” said Matthew O’Brien, lead author and an associate professor of medicine at Northwestern University Feinberg School of Medicine.
STAT reports that the researchers first looked at the number of cases that would be detected under current guidelines (last updated in 2021, lowering the minimum age for screening to 35 from 40).
Scrutinising a national survey that recorded people’s blood sugar levels, the researchers found that the new guidelines do detect a greater share of people with people with prediabetes or diabetes. However, the percentage of cases identified among Asian people is significantly lower than for other racial and ethnic groups.
The researchers then studied the number of cases that would be identified if all adults aged 35-70, regardless of BMI, were screened. That criteria detects more cases within the broad population and more equal percentages of diabetes cases across racial groups.
The team also looked at lowering the minimum age to 18. While that also increases the number cases identified in the broad population, it results in large differences in diabetes detection across racial groups.
The trade-off of expanding the eligibility pool for screening is that there’s also a greater chance of testing people who don’t have prediabetes or diabetes.
Elizabeth Selvin, a professor of epidemiology at the Johns Hopkins Bloomberg School of Public Health and who is unaffiliated with the study, said it doesn’t analyse the costs of expanded screening compared with the benefits.
O’Brien, though, argued that the blood test to screen for these conditions is cheap and comes with few risks. To him, the goal should be to find as many cases as possible.
“I think the best approach is really just to maximise the detection of diabetes across the entire population and across all demographic groups we care about,” he said. Given the serious harms linked to diabetes, including vision impairment, nerve damage, kidney disease, and heart disease, he added.
“The earlier you treat diabetes, it has huge dividends in… getting diabetes under control more easily and then preventing downstream complications.”
Study details
Screening for Prediabetes and Diabetes: Clinical Performance and Implications for Health Equity
Matthew O'Brien, Yan Zhang, Stacy Bailey, Giuseppina Imperatore,
Christopher S. Holliday, Kai McKeever Bullard et al.
Published in the American Journal of Preventive Medicine on 24 March 2023
Introduction
In 2021, the U.S. Preventive Services Task Force recommended prediabetes and diabetes screening for asymptomatic adults aged 35–70 years with overweight/obesity, lowering the age from 40 years in its 2015 recommendation. The U.S. Preventive Services Task Force suggested considering earlier screening in racial and ethnic groups with high diabetes risk at younger ages or lower BMI. This study examined the clinical performance of these U.S. Preventive Services Task Force screening recommendations as well as alternative age and BMI cutoffs in the US adult population overall, and separately by race and ethnicity.
Methods
Nationally representative data were collected from 3,243 non-pregnant adults without diagnosed diabetes in January 2017–March 2020 and analysed from 2021 to 2022. Screening eligibility was based on age and measured BMI. Collectively, prediabetes and undiagnosed diabetes were defined by fasting plasma glucose ≥100 mg/dL or haemoglobin A1c ≥5.7%. The sensitivity, specificity, and predictive values of alternate screening criteria were examined overall, and by race and ethnicity.
Results
The 2021 criteria exhibited marginally higher sensitivity (58.6%, 95% CI=55.5, 61.6 vs 52.9%, 95% CI=49.7, 56.0) and lower specificity (69.3%, 95% CI=65.7, 72.2 vs 76.4%, 95% CI=73.3, 79.2) than the 2015 criteria overall, and within each racial and ethnic group. Screening at lower age and BMI thresholds resulted in even greater sensitivity and lower specificity, especially among Hispanic, non-Hispanic Black, and Asian adults. Screening all adults aged 35–70 years regardless of BMI yielded the most equitable performance across all racial and ethnic groups.
Conclusions
The 2021 US Preventive Services Task Force screening criteria will identify more adults with prediabetes and diabetes in all racial and ethnic groups than the 2015 criteria. Screening all adults aged 35–70 years exhibited even higher sensitivity and performed most similarly by race and ethnicity, which may further improve early detection of prediabetes and diabetes in diverse populations.
STAT article – Study suggests diabetes screening should be guided by age, not weight (Open access)
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