diabetes mellitus, type 2

Importance Heart failure with preserved ejection fraction (HFpEF), defined as HF with an EF of 50% or higher at diagnosis, affects approximately 3 million people in the US and up to 32 million people worldwide. Patients with HFpEF are hospitalized approximately 1.4 times per year and have an annual mortality rate of approximately 15%.

Observations Risk factors for HFpEF include older age, hypertension, diabetes, dyslipidemia, and obesity. Approximately 65% of patients with HFpEF present with dyspnea and physical examination, chest radiographic, echocardiographic, or invasive hemodynamic evidence of HF with overt congestion (volume overload) at rest. Approximately 35% of patients with HFpEF present with “unexplained” dyspnea on exertion, meaning they do not have clear physical, radiographic, or echocardiographic signs of HF. These patients have elevated atrial pressures with exercise as measured with invasive hemodynamic stress testing or estimated with Doppler echocardiography stress testing. In unselected patients presenting with unexplained dyspnea, the H2FPEF score incorporating clinical (age, hypertension, obesity, atrial fibrillation status) and resting Doppler echocardiographic (estimated pulmonary artery systolic pressure or left atrial pressure) variables can assist with diagnosis (H2FPEF score range, 0-9; score >5 indicates more than 95% probability of HFpEF). Specific causes of the clinical syndrome of HF with normal EF other than HFpEF should be identified and treated, such as valvular, infiltrative, or pericardial disease. First-line pharmacologic therapy consists of sodium-glucose cotransporter type 2 inhibitors, such as dapagliflozin or empagliflozin, which reduced HF hospitalization or cardiovascular death by approximately 20% compared with placebo in randomized clinical trials. Compared with usual care, exercise training and diet-induced weight loss produced clinically meaningful increases in functional capacity and quality of life in randomized clinical trials. Diuretics (typically loop diuretics, such as furosemide or torsemide) should be prescribed to patients with overt congestion to improve symptoms. Education in HF self-care (eg, adherence to medications and dietary restrictions, monitoring of symptoms and vital signs) can help avoid HF decompensation.

Conclusions and Relevance Approximately 3 million people in the US have HFpEF. First-line therapy consists of sodium-glucose cotransporter type 2 inhibitors, exercise, HF self-care, loop diuretics as needed to maintain euvolemia, and weight loss for patients with obesity and HFpEF.

Based upon the following two meta-analyses:
1. Alexander JT, et al. The longer-term benefits and harms of glucagon-like peptide-1 receptor agonists: A Systematic review and meta-analysis. JGIM, 2021; 7(2): 415-43.
2. Alexander JT, et al. Longer-term benefits and risks of sodium-glucose cotransporter-2 inhibitors in type 2 diabetes: A systematic review and meta-analysis. JGIM, 2021; 37(2): 439-44, plus Supplementary materials at https://doi.org/10.1007/s11606-021-07227-0.

Selection criteria for the RCTs was that the study period was at least 52 weeks in duration. I assume the average duration of the studies was at least 2 years. So, an absolute risk reduction of mortality of 0.5% would be per 2+ years.

Importance: Gestational diabetes is diabetes that develops during pregnancy. Prevalence of gestational diabetes in the US has been estimated at 5.8% to 9.2%, based on traditional diagnostic criteria, although it may be higher if more inclusive criteria are used. Pregnant persons with gestational diabetes are at increased risk for maternal and fetal complications, including preeclampsia, fetal macrosomia (which can cause shoulder dystocia and birth injury), and neonatal hypoglycemia. Gestational diabetes has also been associated with an increased risk of several long-term health outcomes in pregnant persons and intermediate outcomes in their offspring.

Objective: The USPSTF commissioned a systematic review to evaluate the accuracy, benefits, and harms of screening for gestational diabetes and the benefits and harms of treatment for the pregnant person and infant.

Population: Pregnant persons who have not been previously diagnosed with type 1 or type 2 diabetes.

Evidence assessment: The USPSTF concludes with moderate certainty that there is a moderate net benefit to screening for gestational diabetes at 24 weeks of gestation or after to improve maternal and fetal outcomes. The USPSTF concludes that the evidence on screening for gestational diabetes before 24 weeks of gestation is insufficient, and the balance of benefits and harms of screening cannot be determined.

Recommendation: The USPSTF recommends screening for gestational diabetes in asymptomatic pregnant persons at 24 weeks of gestation or after. (B recommendation) The USPSTF concludes that the current evidence is insufficient to assess the balance of benefits and harms of screening for gestational diabetes in asymptomatic pregnant persons before 24 weeks of gestation. (I statement).

Not available.