Type 2 Diabetes, Adults
The AAFP recommends screening for type 2 diabetes in adults aged 40 to 70 years who have overweight or obesity. (2021) B recommendation
The AAFP concludes that the evidence is insufficient to assess the benefits and harms for screening for type 2 diabetes in adults aged 35-39 years. (2021) I Statement
Clinical consideration from USPSTF: https://www.uspreventiveservicestaskforce.org/uspstf/recommendation/screening-for-prediabetes-and-type-2-diabetes#bootstrap-panel--6
Gestational Diabetes, Pregnant Individuals
The AAFP supports the USPSTF recommendation for screening for gestational diabetes in asymptomatic pregnant persons at 24 weeks of gestation or after. (2021) B recommendation
The AAFP supports the USPSTF statement that there is insufficient evidence to assess the balance of benefits and harms of screening for gestational diabetes in asymptomatic pregnant persons before 24 weeks of gestation. (2021) I statement
Clinical Considerations from USPSTF: https://www.uspreventiveservicestaskforce.org/uspstf/recommendation/gestational-diabetes-screening#bootstrap-panel--6
The AAFP has reviewed the U.S. Preventive Services Task Force evidence report and agrees that asymptomatic pregnant individuals should be screened for gestational diabetes at 24 weeks gestation or after. The AAFP also agrees that there is insufficient evidence for screening prior to 24 weeks gestation.1
The AAFP has also reviewed the US Preventive Services Task Force evidence report and agrees that nonpregnant adults aged 40 to 70 who have obesity or overweight be screened for type 2 diabetes as part of risk assessment for cardiovascular disease.2 Screening in this setting refers to measuring fasting plasma glucose, HbA1c level, or using an oral glucose tolerance test. A fasting plasma glucose level of 126 mg/dL (6.99 mmol/L) or greater, an HbA1c level of 6.5% or greater, or a 2-hour post-load glucose level of 200 mg/dL (11.1 mmol/L) or greater are considered to be consistent with the diagnosis of type 2 diabetes.
Patient preferences should be taken into account when determining which test is used and a diagnosis of type 2 diabetes should be confirmed before offering interventions. There is limited evidence on the best rescreening intervals for adults with normal results but screening every 3 years is a reasonable option.
However, the AAFP feels that there is currently insufficient evidence to recommend screening adults aged 35 to 39. Almost all of the evidence that was presented looked at adults over the age of 40 and there were no subgroup analyses that specifically examined screening at younger ages. Further, in contrast to individuals diagnosed with diabetes due to symptoms, there was no demonstrated improvement in mortality, cardiovascular events, or other health outcomes in individuals with screen-detected type 2 diabetes.
The AAFP does not agree that there is evidence to support screening for prediabetes. While AAFP acknowledges that diabetes, like all chronic conditions, exists on a continuum and that insulin resistance is a risk factor for developing diabetes, the current evidence does not show improvement in long term health outcomes for screening for prediabetes in adults who have obesity or overweight. Screening for prediabetes is neither sensitive nor specific and may result in false positives (overdiagnosis) or false negatives (false reassurance).
The evidence did show a reduction in the incidence of diabetes in individuals at risk for diabetes who received intense lifestyle interventions or metformin, however there was not an associated improvement in health outcomes. The impact of the interventions was observed to be greatest at shorter lengths of follow up with the included trials providing data for 1-3.9 years. Lifestyle interventions to prevent progression for prediabetes to diabetes are effective in reducing weight, blood pressure and cholesterol and would likely be recommended and beneficial for these individuals, even in the absence of screening.
Moreover, the AAFP is concerned that harms of screening and the resulting labeling or stigmatizing of individuals have not been adequately assessed and may lead to impacts on patient health and wellbeing. Instead, there may be an increase in the number of individuals who are on medications as the provision or referral to intensive lifestyle interventions is not readily accessible in rural and underserved areas. There is also concern that persons of color will be disproportionately stigmatized and face additional barriers to care. Increases in labeling is a great concern as there is stigma around diabetes both within and outside of the healthcare system as diabetes is routinely viewed as a disease resulting from “poor life choices” and “lack of self-control” rather than a combination of genetics and social determinants of health.
These recommendations are provided only as assistance for physicians making clinical decisions regarding the care of their patients. As such, they cannot substitute for the individual judgment brought to each clinical situation by the patient's family physician. As with all clinical reference resources, they reflect the best understanding of the science of medicine at the time of publication, but they should be used with the clear understanding that continued research may result in new knowledge and recommendations. These recommendations are only one element in the complex process of improving the health of America. To be effective, the recommendations must be implemented.