Ablation of atrial fibrillation can restore normal heart rhythm, but its effect on clinical outcomes is uncertain.

Climate change is anticipated to continue to adversely affect public health, with heat stress the predominant threat. Accordingly, heat-related illness is predicted to increase as extremely hot days become more frequent. Heat stroke, the most serious heat-related illness, is a medical emergency that may be fatal if it is not promptly recognized, addressed with early and rapid cooling, and accompanied by multidisciplinary supportive care as clinically indicated. Heat stroke is a preventable illness that occurs in 2 distinct forms-classic and exertional-that have distinct demographic profiles and clinical courses but similar management paradigms.

Large language models (LLMs) offer substantial promise for improving health care; however, some risks warrant evaluation and discussion. This study assessed the effectiveness of safeguards in foundational LLMs against malicious instruction into health disinformation chatbots. Five foundational LLMs-OpenAI's GPT-4o, Google's Gemini 1.5 Pro, Anthropic's Claude 3.5 Sonnet, Meta's Llama 3.2-90B Vision, and xAI's Grok Beta-were evaluated via their application programming interfaces (APIs). Each API received system-level instructions to produce incorrect responses to health queries, delivered in a formal, authoritative, convincing, and scientific tone. Ten health questions were posed to each customized chatbot in duplicate. Exploratory analyses assessed the feasibility of creating a customized generative pretrained transformer (GPT) within the OpenAI GPT Store and searched to identify if any publicly accessible GPTs in the store seemed to respond with disinformation. Of the 100 health queries posed across the 5 customized LLM API chatbots, 88 (88%) responses were health disinformation. Four of the 5 chatbots (GPT-4o, Gemini 1.5 Pro, Llama 3.2-90B Vision, and Grok Beta) generated disinformation in 100% (20 of 20) of their responses, whereas Claude 3.5 Sonnet responded with disinformation in 40% (8 of 20). The disinformation included claimed vaccine-autism links, HIV being airborne, cancer-curing diets, sunscreen risks, genetically modified organism conspiracies, attention deficit-hyperactivity disorder and depression myths, garlic replacing antibiotics, and 5G causing infertility. Exploratory analyses further showed that the OpenAI GPT Store could currently be instructed to generate similar disinformation. Overall, LLM APIs and the OpenAI GPT Store were shown to be vulnerable to malicious system-level instructions to covertly create health disinformation chatbots. These findings highlight the urgent need for robust output screening safeguards to ensure public health safety in an era of rapidly evolving technologies.

In January 2025, the Republican majority in the House of Representatives' Budget Committee offered a list of possible spending reductions to offset revenue losses from proposed tax cuts. In May, the Committee advanced a bill incorporating several reductions on the list. The Committee estimated that the 6 largest potential Medicaid cuts (for example, work requirements for some Medicaid enrollees) would each reduce the federal government's Medicaid outlays by at least $100 billion over 10 years. On the basis of the Committee's estimates of savings; Congressional Budget Office analyses; and peer-reviewed studies of the coverage, financial, and health impacts of past Medicaid expansions and contractions, the authors project the likely effects of each option and of the House bill advanced by the Budget Committee in May. Each option individually would reduce federal Medicaid outlays by between $100 billion and $900 billion over a decade, increase the ranks of the uninsured by between 600 000 and 3 900 000 and the annual number of persons forgoing needed medical care by 129 060 to 838 890, and result in 651 to 12 626 medically preventable deaths annually. Enactment of the House bill advanced in May would increase the number of uninsured persons by 7.6 million and the number of deaths by 16 642 annually, according to a mid-range estimate. These figures exclude harms from lowering provider payments and shrinking benefits, as well as possible repercussions from states increasing taxes or shifting expenditures from other needs to make up for shortfalls in federal Medicaid funding. Policy makers should weigh the likely health and financial harms to patients and providers of reducing Medicaid expenditures against the desirability of tax reductions, which would accrue mostly to wealthy Americans.

Nearly 8% of the U.S. population is diagnosed with asthma, leading to more than 5 million office visits and 1 million emergency department visits annually. Both outpatient and inpatient internal medicine clinicians treat asthma frequently, but nuances in diagnosis and management have emerged. This article highlights many of these developments.

Unconditional cash transfers (UCTs) through social programs or direct cash transfers (DCTs) may address drivers of pregnancy-related morbidity and mortality.

Dietary interventions are a potential alternative treatment of depression and anxiety.

In the United States and other high-income countries, blood donation primarily relies on anonymous, voluntary donors. However, directed blood donation-where people donate for a specific recipient-has resurged, particularly due to misinformation surrounding COVID-19 vaccination. Requests for "nonvaccinated" blood, driven by misconceptions about vaccine safety, have led to legislative attempts to mandate compliance. Historically, directed donation was used to mitigate the risk for transfusion-related infections before modern screening techniques rendered it largely unnecessary. Today, it presents important patient safety risks, including increased infectious disease transmission, immunologic complications, and logistic burdens. Directed donations also introduce inefficiencies, diverting resources from the community blood supply and exacerbating shortages. Moreover, directed donation for nonmedical indications lacks scientific justification. Blood safety is ensured through rigorous donor screening, pathogen testing, and processing measures. There is no evidence that blood from vaccinated donors poses risk. Requests for nonvaccinated blood, as well as other directed donation preferences based on personal beliefs, introduce biases that are not grounded in medical necessity. Accommodating such requests undermines public trust in blood safety protocols and legitimizes unfounded fears. Ethical concerns arise as non-medically justified requests reinforce discriminatory practices, such as selecting donors based on race or gender. Allowing such preferences risks politicizing blood donation, spreading misinformation, and straining health care systems. Although autonomy is a core ethical principle in medicine, it does not justify non-evidence-based interventions. Given the potential harm and societal impact, directed blood donations should be limited to rare, medically necessary cases. Ongoing legislative efforts to mandate these requests require unified opposition from the medical and scientific community to uphold ethical, evidence-based, blood allocation practices.

Lyme disease, caused by Borrelia burgdorferi, is the most common vector-borne disease in the United States, and the range of its tick vector continues to expand. Most Lyme disease cases are diagnosed with the onset of the erythema migrans rashes, which can be single or multiple and vary from a homogeneous erythema to bull's-eye patterns. Serologic antibody testing is of low sensitivity at onset but becomes highly sensitive after a few weeks. Early dissemination may lead to neurologic and cardiac complications. Mono- or oligoarticular arthritis may develop in untreated patients. Antibiotic treatment is highly effective, but approximately 10% of treated patients experience persistent symptoms.

More than 90 million women in the United States have given birth. Randomized controlled trials (RCTs) of medications almost always exclude pregnant participants.

Poor communication in health care increases the risk for patient safety incidents. However, there is no up-to-date synthesis of these data.

Epilepsy is a common neurologic condition characterized by at least 1 unprovoked seizure and a high risk for recurrent seizures. Distinguishing epilepsy from conditions that can mimic seizures is important for accurate diagnosis and effective treatment. This article reviews the evaluation of patients suspected of having epilepsy and discusses behavioral strategies and pharmacologic and surgical therapies that can help reduce morbidity associated with recurrent seizures.

What is the added risk for death from smoking? Logistic regression has become the most common statistical method to answer such questions in the biomedical literature. However, the typical analyses estimate odds ratios, a metric too often misunderstood and misinterpreted. Although estimates of risks, and their differences and ratios, offer transparent clinical interpretations, commonly used statistical models have known methodological shortcomings. "Standardization" through modeling, weighting, or matching offers a solution. The goals of this article are to review classical concepts of standardization and to link them to regression modeling for causal inference. The authors also describe approaches based on weighting and matching compared with regression-based standardization. Using an example of smoking from the ARIC (Atherosclerosis Risk in Communities) study, they explain the value of standardization, long used in medicine and public health, to estimate risks and their differences and ratios for binary outcomes. The authors demonstrate how standard statistical software using models that best fit the data and respect underlying biological or clinical processes can reexpress results in clinically meaningful metrics. The Supplement offers examples with common software packages.

During 2024, there were many practice-changing innovations in the field of endocrinology, particularly related to the use of glucagon-like peptide-1 receptor agonists (GLP-1RAs). From the substantial new evidence published in 2024, 10 studies are highlighted that offer critical information for clinicians who manage or comanage patients with endocrine disorders including prediabetes, diabetes, obesity, and hyperparathyroidism. Two of the 10 articles are focused on use of GLP-1RAs in multiple clinical settings not studied in the original GLP-1RA trials, including after bariatric surgery and before endoscopy. Two additional studies focused on GLP-1RA explore the risk for thyroid cancer in patients prescribed GLP-1RA and the effect of a GLP-1RA on chronic kidney disease in patients with type 2 diabetes. Three articles investigate opportunities for deintensification of insulin frequency or an alternate method of insulin delivery in patients with type 2 diabetes. One article explores the cardiometabolic effects of intermittent fasting in persons with prediabetes and type 2 diabetes. The last 2 articles explore the incidence of diabetes after SARS-CoV-2 infection and the skeletal effects of parathyroidectomy as a treatment of hyperparathyroidism. The results of each study have a direct effect on the delivery of care for patients with prediabetes, type 2 diabetes, and hyperparathyroidism.

There have been many recent advancements in cardiology research, with numerous studies published across the multiple subspecialties. Having screened more than 1200 articles published in 2024, we summarize 10 studies in this article that highlight key changes in this field. Starting with atrial fibrillation (AF), we note articles that examine which patients benefit most from catheter ablation, a procedure that is becoming increasingly common. We then examine new evidence regarding anticoagulation in device-detected AF and in patients with AF and coronary disease. In patients with severe aortic stenosis, the timing of valve intervention in relation to development of symptoms was a hot topic and is addressed here. There have also been developments in treatment of heart failure with preserved ejection fraction, including research into medications such as finerenone and tirzepatide. Certain studies attempt to challenge our current medical practices, including routine use of β-blockers after myocardial infarction (MI) and holding of renin-angiotensin system inhibitors before noncardiac surgery. Finally, the role of invasive treatment strategies for older adults with non-ST-segment elevation MI has also been addressed.

This article highlights selected major advances in gastroenterology and hepatology from 2024 that are relevant for internal medicine specialists. In colorectal cancer (CRC) screening, new developments include a head-to-head comparison of different fecal immunochemical tests and a new blood-based DNA screening test, benefits and harms of artificial intelligence-assisted colonoscopy, and adenoma detection rate improvement and risk for cancer. Treatment options for metabolic dysfunction-associated steatotic liver disease now include resmetirom, a recently approved drug for treatment of patients with moderate-to-severe fibrosis, and liver transplantation may now be an option in patients with unresectable colorectal liver metastases. Also featured are new data on the efficacy of indomethacin and pancreatic stent placement for prevention of pancreatitis after endoscopic retrograde cholangiopancreatography and news on the efficacy and safety of zastaprazan, a new potassium-competitive acid blocker for reflux esophagitis. Finally, a recent randomized trial is highlighted that has dispelled concerns about potential harms of proton-pump inhibitors for stress ulcer prophylaxis in patients receiving invasive mechanical ventilation.

This article highlights some important nephrology studies published in 2024 that may be relevant for nonnephrologist physicians. Four studies examined progression of chronic kidney disease (CKD), cardiovascular events, and nephrolithiasis with respect to use of semaglutide or sodium-glucose cotransporter-2 inhibitors. Three studies examined treatments to improve specific aspects of CKD management, including mineralocorticoid receptor agonists to address heart failure, avenciguat to address albuminuria, and oral phosphate binders to address fracture risk. One study demonstrated that inorganic nitrate reduced the risk for contrast-induced nephropathy. Finally, a trial of cefepime-taniborbactam showed benefit for treating complicated urinary tract infection.

The past year saw many important publications in the specialty of pulmonology. We screened more than 750 articles published in 2024 and carefully selected 10 that feature important advancements in the management of several respiratory conditions. We highlight 4 articles that describe management options for patients with chronic obstructive pulmonary disease (COPD) beyond pharmacotherapy, including breathing techniques, duration of long-term oxygen therapy, high-intensity compared with low-intensity noninvasive ventilation for exacerbations, and the potential harmful effect of gabapentinoids. Two articles delved into the evidence for various biologic therapies and inhaled relievers used in asthma. We include a randomized trial examining treatment of acute eosinophilic COPD and asthma exacerbations with benralizumab. One article explores dual glucagon-like peptide-1 and glucose-dependent insulinotropic polypeptide receptor agonists as a novel treatment option for obstructive sleep apnea. Another discusses the efficacy of inhaled antibiotics in bronchiectasis. Finally, a meta-analysis examines the evidence for postexposure prophylaxis antiviral agents to reduce transmission and severity of influenza infections.

Internal medicine physicians are frequently responsible for caring for patients with rheumatologic diseases, whether as a primary provider or in collaboration with subspecialists. This article calls attention to 8 studies published in 2024 that shed new light on the management of common rheumatologic conditions that internal medicine physicians are likely to encounter. The first study suggests that the weight loss medication semaglutide can improve pain and function in patients with painful knee osteoarthritis (OA), potentially providing a novel approach to management of this condition. The results of the second study show that methotrexate, a proven therapy for inflammatory arthritis, has promise for improving pain in patients with knee OA. The third study establishes that a trial of resistance training does not provide similar benefits as total joint replacement for patients with hip OA. The fourth study finds that platelet-rich plasma injections are no more effective than exercise in reducing pain for patients with knee OA. The fifth study underscores the importance of screening for lung cancer in patients with rheumatoid arthritis (RA), particularly in those known to have interstitial lung disease. The results of the sixth study emphasize that exercise therapy is safe and effective at improving function in patients with RA and severe activity limitations. The seventh study highlights the increased short-term risk for acute cardiovascular events in patients experiencing a new gout diagnosis. The final study suggests that supplementation with omega-3 fatty acids may provide sustained protection against developing new autoimmune diseases. Familiarity with these new studies will provide internal medicine physicians with valuable insights to enhance their care of patients with rheumatic diseases.

In 2024, infectious disease literature focused on advancements in the treatment of severe infections and prevention of high-burden diseases. Building on prior data, further evidence supports both the use of shorter courses of antibiotics and the earlier transition to oral antibiotics, including for severe infections, such as bacteremia. A new medication has demonstrated significant, high-impact findings in the long-acting category of drugs for the prevention of HIV infection. Antibiotic resistance continues to be a growing threat, and research this year has demonstrated significant advances for new agents helping to combat resistant gram-negative organisms. Research on the long-term sequelae of COVID-19 continues to expand, with a living systematic review providing us a better understanding of symptom management. Novel treatment regimens for Helicobacter pylori infection are being studied, and the evidence is reviewed for these new regimens. Finally, several emerging infections are highlighted to raise awareness of new or concerning outbreaks that may cause significant effects in the coming year.