Is diabetes screening important? Not! What matters is early pharmacological intervention!

Prediabetes and type 2 diabetes are common, and risk factors associated with developing diabetes in adults include old age, family history, overweight and obesity, dietary and lifestyle factors, environmental exposures, and more
.
Currently, there are three tests that can be used to identify diabetes or prediabetes: glycosylated hemoglobin (HbA1c) concentration, fasting blood glucose level, or oral glucose tolerance test
.

Screening for prediabetes and type 2 diabetes

In 2015, the U.
S.
Preventive Services Task Force (USPSTF) recommended screening for blood glucose levels in overweight or obese adults ages 40 to 70 as part of
a cardiovascular risk assessment.
In addition, clinicians are advised to provide counseling and intensive interventions for patients with abnormal blood glucose levels to promote healthy eating and physical activity in high-risk populations (recommendation B).

This study evaluates the latest evidence for
prediabetes screening in the United States.

The investigators reviewed 89 publications (N = 68882).

Two randomised clinical trials (RCTs) (25,120 participants) found no significant difference in
all-cause or cause-specific mortality at 10 years between screening and control groups.
In a prospective diabetes study in the UK, sulfonylureas or insulin enhanced glycaemic control improved health
.

For example, for all-cause mortality, the 20-year relative risk (RR) was 0.
87 (assessed after 10 years of trials).

For overweight people, metformin enhanced glycaemic control improved health outcomes and benefited longer
at 10 years of follow-up.
Lifestyle interventions (most interventions longer than 360 minutes) in obese or overweight people with prediabetes were associated
with reduced diabetes incidence.
Lifestyle interventions were also associated with improvements in intermediate outcomes such as weight loss, body mass index, systolic and diastolic blood pressure
.
Metformin is associated
with a significant reduction in the incidence of diabetes and a reduction in body weight and body mass index.

Results of a meta-analysis of trials evaluating interventions for people with a prodrous diabetes disorder

This evidence assesses the benefits and harms
of prediabetes and diabetes screening.
For the benefit of screening, evidence from two trials (25,120 total participants) suggests no significant benefit of diabetes screening on mortality reduction, and data on outcomes other than mortality are limited because data are missing for most participants and trials may have been followed up for too short a benefit
on health outcomes.
Neither trial assessed prediabetes screening, nor did they assess initial screening
for HbA1c or fasting blood glucose.

Regarding the harms of screening, the trials reported no significant differences between the screening and control groups in anxiety, depression, anxiety or self-reported health, and did not include studies
on labeling, harms, burden, inconvenience or unnecessary testing and treatment of false-positive results.

Overall, no significant benefit
of diabetes screening tests in improving mortality was found.
However, interventions improved health outcomes for people with newly diagnosed (not screened) diabetes, and for obese or overweight patients with prediabetes, the intervention was associated
with reduced diabetes incidence and improved other intermediate outcomes.

References: Jonas DE, Crotty K, Yun JDY, et al.
Screening for Prediabetes and Type 2 Diabetes:Updated Evidence Report and Systematic Review for the US Preventive Services Task Force .
JAMA.
2021; 326(8):744–760.
doi:10.
1001/jama.
2021.
10403