Hypoglycemia Hospitalizations Are Getting Deadlier and More Expensive in the US

When blood sugar crashes below 70 mg/dL, the body sounds an alarm: sweating, palpitations, tremors, hunger, and dizziness. Below 55 mg/dL, confusion can set in, and for tens of thousands of Americans each year, the crisis ends in a hospital bed. A new national analysis of US inpatient data from 2017 to 2022 reveals a troubling paradox: while the rate of hospitalizations primarily caused by hypoglycemia fluctuated over the six-year window, the patients who were admitted became sicker, stayed longer, died more often, and generated steadily rising hospital bills. The findings, drawn from the largest publicly available all-payer inpatient database in the United States, show that severe low blood sugar is increasingly affecting patients with a heavy burden of chronic cardiometabolic disease.

The research team analyzed the National Inpatient Sample, a 20 percent stratified sample of discharges from US community hospitals sponsored by the Agency for Healthcare Research and Quality. After applying discharge weights, the final cohort included 330,910 adult hospitalizations with a principal diagnosis of hypoglycemia, identified through ICD-10-CM codes capturing drug-induced, diabetes-related, and other or unspecified forms of the condition. The typical patient was 67 years old, and women accounted for 52 percent of admissions. White individuals formed the largest racial group at 53 percent, followed by Black individuals at 28 percent and Hispanic individuals at 12 percent. The burden was concentrated in the South, which hosted 44 percent of admissions, and in urban teaching hospitals, which accounted for 70 percent. Medicare covered 70 percent of the hospitalizations, underscoring how heavily the condition weighs on older, chronically ill populations.

The comorbidity profile reads like a catalog of the American chronic disease epidemic. Type 2 diabetes was present in 91 percent of admissions, chronic kidney disease in 47 percent, hyperlipidemia in 53 percent, hypertension in 40 percent, atrial fibrillation in 18 percent, and obesity in 17 percent. Despite this heavy disease load, overall in-hospital mortality was 1.6 percent, with 5,300 admissions ending in death. The median length of stay was 3.0 days, and the median inflation-adjusted total hospital cost, standardized to 2022 dollars, was $7,319. But those headline numbers conceal a dynamic and deteriorating picture that only emerged when the researchers tracked outcomes year by year.

Admission rates followed a nonlinear arc. Primary hypoglycemia discharges peaked near 2019 at roughly 195 per 100,000 adult discharges, then declined during 2020 and 2021, before partially rebounding in 2022. Meanwhile, the outcomes within those admissions worsened. In-hospital mortality rose after 2019 and reached its highest point around 2021. Mean length of stay climbed from about 3.9 days in 2017 to about 4.5 days in 2022, and mean inflation-adjusted costs rose from under $10,000 in 2017 to above $11,000 by 2021 and 2022. In adjusted models, compared with 2017, the odds of in-hospital death were significantly higher in 2020, 2021, and 2022, with 2021 showing the largest increase at an odds ratio of 1.44. Length of stay and cost showed parallel elevations across the same later years.

The strongest predictors of death were not the most common conditions. Congestive heart failure carried nearly three-fold higher adjusted odds of in-hospital mortality, the largest association in the entire model, and atrial fibrillation raised mortality odds by 51 percent. Advanced age added 2 percent higher odds per year, and men had higher adjusted mortality than women, whose odds were 20 percent lower. Patients from micropolitan areas had 50 percent higher mortality odds than those from large metropolitan areas, and small metropolitan residents had 23 percent higher odds, a pattern the authors attribute to delayed access to care, fewer endocrinologists, weaker emergency services, and less continuity after discharge. Small hospitals showed lower mortality odds than large ones, likely reflecting case selection, since the most complex patients are often transferred to larger centers.

In a striking inversion, several of the most prevalent comorbidities were associated with lower adjusted mortality. Diabetes, hypertension, obesity, hyperlipidemia, and chronic kidney disease all showed reduced odds of death in the model. The researchers caution against interpreting these inverse associations as biological protection. Patients with these chronic conditions who were hospitalized primarily for hypoglycemia may represent a comparatively lower-acuity subgroup than those whose low blood sugar was secondary to more severe illness, and differential comorbidity coding in administrative data may further contribute. Similar paradoxical relationships between common cardiometabolic conditions and short-term mortality have been reported elsewhere and are generally attributed to confounding by indication or selection rather than true protective mechanisms.

Resource use told a more consistent story. Congestive heart failure increased adjusted length of stay by 64 percent and adjusted cost by 64 percent, the largest effects in both models. Iron deficiency anemia followed, raising stay duration by 25 percent and cost by 24 percent, while atrial fibrillation increased both by roughly 11 to 13 percent. Chronic kidney disease, alcohol abuse, and obesity mainly drove costs upward. Geography and hospital type mattered as well: urban teaching hospitals had 25 percent longer stays than rural hospitals, the West showed the largest regional cost increase at 27 percent above the Midwest, and the Northeast followed at 18 percent. Black patients had longer adjusted stays and higher adjusted costs than White patients, findings that parallel national data showing greater inpatient and emergency department spending among Black Americans despite lower ambulatory-care spending.

The temporal pattern of admissions may owe as much to the pandemic as to the disease itself. The researchers point out that COVID-19 severely disrupted outpatient management of heart failure, atrial fibrillation, chronic kidney disease, and diabetes. During the early outbreak, participation of heart failure patients in outpatient clinics, cardiac rehabilitation centers, and remote monitoring systems fell drastically, and by early 2020, 88.5 percent of heart failure outpatient visits had shifted to telehealth. The 2020 to 2021 decline in hypoglycemia admissions, the authors argue, may therefore reflect reduced care-seeking and disrupted outpatient management rather than a genuine fall in disease severity, while the later rebound and worsening mortality, length of stay, and cost may reflect the accumulated effect of delayed chronic disease care in a population whose cardiometabolic burden was already increasing.

The analysis also exposes a gap in how the United States tracks and prevents severe hypoglycemia compared with other nations. Programs such as the 2014 national action plan for adverse event prevention and the 2017 Avalere Hypoglycemia Prevention Initiative were launched to curb medication-related low blood sugar, but their implementation was segmented rather than national, and even the Diabetes Self-Management Education and Support system is used by only 5 percent of Medicare beneficiaries during the first year of diagnosis. By contrast, the Danish Adult Diabetes Registry, operating at the national level, has been linked to a fall of more than 60 percent in diabetes-related hypoglycemia hospitalizations between 1998 and 2018. In the United Kingdom, the National Diabetes Inpatient Audit tracked severe hypoglycemic episodes among inpatients with diabetes as they declined from 12 percent in 2010 to 7 percent in 2019, with injectable rescue treatment falling from 2.4 percent to 1.4 percent.

The authors acknowledge important limitations. Administrative discharge data capture only severe events that reached a hospital, missing hypoglycemic episodes that never prompted a visit. Clinical parameters such as HbA1c, blood glucose levels, and medication records could not be analyzed, and the retrospective design means the observed associations mark risk rather than prove causation. The six-year study period also limits finer characterization of temporal changes. Still, the message is clear: older adults, men, micropolitan and small metropolitan residents, and patients with heart failure or atrial fibrillation form the highest-risk groups, and heart failure, iron deficiency anemia, and atrial fibrillation are the major drivers of resource use. The researchers call for a unified national hypoglycemia surveillance and prevention system, stronger outpatient monitoring, and better coordination between diabetes, cardiovascular, and renal care.

Subject of Research: National trends and predictors of adverse outcomes in US hypoglycemia hospitalizations, 2017-2022

Article Title: National Trends and Predictors of Adverse Outcomes in Hypoglycemia Hospitalizations in the United States, 2017–2022

Article References: Bin Gulzar, A. H., Hakeem, S., Sohail, M. U., Tahir, A., Tariq, T., Shehroz, R., Khan, M. S., Rahim, I., Aiman, U., Ashraf, M. A., Rai, S., Mavora, M., Cheema, A. A. A., & Nadeem, H. (2026). National Trends and Predictors of Adverse Outcomes in Hypoglycemia Hospitalizations in the United States, 2017–2022. Endocrinology, Diabetes & Metabolism, 9(6), Article e70370. https://doi.org/10.1002/edm2.70370

Image Credits: AI Generated

DOI: 10.1002/edm2.70370

Keywords: hypoglycemia, hospitalization, diabetes, heart failure, atrial fibrillation, inpatient mortality, healthcare costs, National Inpatient Sample, COVID-19, chronic kidney disease, National, Trends