“Clinical Research Bites” –⁠ 2025/39

A “Beer Belly” Is More Dangerous for the Heart Than a High BMI

A new German study has shown that excess visceral fat damages the heart through different mechanisms than obesity defined by a high body mass index (BMI). While a high BMI is associated with cardiac hypertrophy, visceral obesity leads to concentric cardiac remodeling. One possible explanation is that general obesity increases blood volume and cardiac workload, causing hypertrophy and ventricular dilation, whereas excess visceral fat triggers metabolic stress and chronic inflammation, contributing to the development of cardiac hypertrophy without dilation.

In 2,173 individuals aged 45–74 years without known heart disease from the population-based Hamburg City Health study, 3T cardiovascular MRI demonstrated that increasing waist-to-hip ratio (WHR) was associated with greater left ventricular mass and reduced stroke volume of both the left and right ventricles. This association was stronger in men than in women. With increasing BMI, left ventricular mass and stroke volume increased, while right ventricular stroke volume did not change significantly.

According to German cardiologists, assessment of visceral obesity —⁠ commonly seen in German and Czech individuals who regularly consume beer —⁠ should be an integral part of cardiovascular risk evaluation. Relying solely on BMI may lead to underestimation of the risk of concentric cardiac remodeling.

Source: Ellis B. “Beer belly” can cause cardiac damage differently from general obesity. Medscape, 2025 Dec 11. Available at: www.medscape.com/viewarticle/beer-belly-can-cause-cardiac-damage-differently-than-general-2025a1000ys4

Sentinel Lymph Node Biopsy May Not Be Necessary in Early Breast Cancer

According to results of the BOOG 2013-08 study presented at the December San Antonio Breast Cancer Symposium (SABCS), sentinel lymph node biopsy (SLNB) may be omitted in the treatment of early-stage breast cancer. Five-year regional recurrence–free survival (RRFS) was comparable in patients who underwent SLNB and those who did not. Omitting SLNB is cost-effective and reduces the risk of lymphedema, thereby improving quality of life and accelerating recovery.

The study included 1,733 women with a mean age of 61 years with unilateral breast cancer cT1–T2 < 5 cm (87% HR⁺/HER2‾), without lymph node involvement. Patients underwent breast-conserving surgery and whole-breast radiotherapy. Systemic treatment, including chemotherapy ± targeted therapy and hormonal therapy, was similar in both groups. Five-year RRFS was 96.6% in the SLNB group and 94.2% in the group without SLNB, with the difference remaining within the non-inferiority margin.

According to the study authors, SLNB can therefore be safely omitted in these patients. It remains unclear, however, whether this also applies to patients receiving de-escalated radiotherapy. The study is ongoing and is expected to be completed in July 2027.

Source: Brooks M. OK to skip sentinel node biopsy in some early breast cancers. Medscape, 2025 Dec 12. Available at: www.medscape.com/viewarticle/ok-skip-sentinel-node-biopsy-some-early-breast-cancers-2025a1000yxf

FDA Approves At-Home Transcranial Brain Stimulation System for Depression in the USA

The U.S. Food and Drug Administration (FDA) has approved FL-100 —⁠ the first transcranial direct current stimulation (tDCS) system for at-home use in adults with moderate to severe major depressive disorder (MDD). Its use is indicated following a recent episode as monotherapy or adjunctive treatment. In the United States, the system will be available by prescription as an app for iOS and Android, likely in the second quarter of 2026. It enables electrical stimulation of the prefrontal cortex —⁠ a brain region involved in mood regulation and stress response that often shows reduced activity in people with depression.

The system was evaluated in a randomized, double-blind, sham-controlled trial. Patients (n = 174) self-administered the treatment at home under remote supervision for 30 minutes, five times per week for three weeks, followed by three times per week for seven weeks. Results showed a greater reduction in HDRS scores (Hamilton Depression Rating Scale: –9.4 vs. –7.1 points; p = 0.012), as well as a higher proportion of clinical responses (58 vs. 38%; p = 0.017) and remissions (45 vs. 22%; p = 0.004) in the tDCS group. Adverse events were mild and transient, most commonly including skin dryness, irritation or redness with prolonged use, headache, or itching at the application site. Incorrect placement of electrode pads could result in skin burns.

Source: Brooks M. FDA OKs first at-home brain stimulation device for depression. Medscape, 2025 Dec 11. Available at: www.medscape.com/viewarticle/fda-oks-first-home-brain-stimulation-device-depression-2025a1000yu4

WHO Reaffirms No Link Between Vaccination and Autism

On December 11, 2025, Reuters reported on a statement by the World Health Organization’s (WHO) vaccine safety committee that a new review of scientific evidence found no association between vaccination and the occurrence of autism spectrum disorders. This reaffirmed conclusions published more than 20 years ago.

The WHO Global Advisory Committee on Vaccine Safety reviewed two systematic reviews including studies published between 2010 and August 2025. Vaccines were evaluated overall, as well as vaccines containing thiomersal —⁠ a mercury-based preservative long suspected of potentially increasing autism risk. Of 31 studies, 20 found no evidence of an association between vaccination and autism. The remaining 11 studies suggesting a possible link were found to have significant methodological limitations and a high risk of bias.

Source: WHO reaffirms no link between vaccines and autism. Reuters, Medscape, 2025 Dec 11. Available at: www.medscape.com/s/viewarticle/who-reaffirms-no-link-between-vaccines-and-autism-2025a1000yro

Editorial Team, Medscope.pro