Background: Multiple Sclerosis (MS) is a chronic neurological disorder affecting 2.8 million individuals worldwide, characterized by motor dysfunction and cognitive impairment that remain poorly addressed by pharmacological interventions alone. Transcranial Direct Current Stimulation (tDCS) has emerged as a promising non-invasive neuromodulation technique for symptom management in MS patients. Objectives: This systematic review and meta-analysis aimed to evaluate the efficacy of tDCS in improving motor and cognitive functions in patients with MS, and to assess its safety profile. Methods: A comprehensive literature search was conducted across PubMed, Scopus, EMBASE, Wiley Online Library, and Google Scholar databases. Studies were selected based on PICOS criteria, including randomized controlled trials and quasi-experimental studies involving adults (≥ 18 years) with all types of MS receiving tDCS interventions. Methodological quality was assessed using RoB 2.0 and ROBINS-I. Meta-analyses were performed using RevMan 5.4.1 with random-effects models for outcomes with substantial heterogeneity and fixed-effects models where I ² = 0%. Additionally, the protocol was prospectively registered with the Open Science Framework. Results: Twenty-two studies published between 2015 and 2025 were included in this review. Meta-analysis revealed that tDCS significantly improved information processing speed (SDMT: MD = 7.71, 95% CI: 1.60—13.82, p = 0.01) and functional mobility (TUG: MD = -1.03 s, 95% CI: -2.08—0.02, p = 0.05). While individual studies showed improvements in gait speed and balance, pooled analyses for these outcomes did not reach statistical significance (gait speed: MD = 0.16 m/s, 95% CI: -0.07—0.38, p = 0.18; Berg Balance Scale: MD = 1.18, 95% CI: -2.03—4.39, p = 0.47). Qualitative analysis revealed consistent improvements in manual dexterity, working memory, executive function, and complex attention. Additionally, no serious adverse events were reported across studies; mild and transient side effects (e.g., tingling, itching) were noted, and completion rates were high (98% in studies that reported them). Conclusion: This systematic review provides preliminary evidence supporting tDCS as a potentially beneficial adjunctive intervention for MS patients, particularly for cognitive processing speed enhancement based on two small studies. While individual studies reported motor improvements, pooled meta-analyses for gait speed and balance failed to demonstrate statistical significance, indicating insufficient evidence for definitive motor benefits despite positive signals in individual trials. The substantial limitation of small study numbers per meta-analysis (2—6 studies), combined with limited MS subtype-specific data in most studies, significantly constrains confidence in these findings and limits assessment of external validity across different MS populations. Larger, standardized, multi-center randomized controlled trials with adequate subgroup representation and extended follow-up periods are essential to establish clinical significance and treatment durability.

Background: Abdominal aortic aneurysm (AAA) remains an important cause of cardiovascular mortality in the United States despite advances in screening, surveillance, and aneurysm repair. Contemporary national analyses evaluating long-term AAA mortality trends across demographic and geographic subgroups remain limited, particularly following the COVID-19 pandemic period. Objective: To evaluate temporal trends in AAA-related mortality among U.S. adults aged ≥ 65 years from 1999 to 2024 and characterize demographic and geographic disparities. Methods: A retrospective population-based study was conducted using the CDC WONDER Multiple Cause of Death database. AAA-related deaths were identified using International Classification of Diseases, Tenth Revision (ICD-10) codes I71.3 and I71.4. Age-adjusted mortality rates (AAMRs) per 100,000 population were calculated using the 2000 U.S. standard population. Mortality trends were stratified by sex, age, race/ethnicity, census region, and urbanization status. Joinpoint regression analysis was used to estimate annual percent change (APC) and average annual percent change (AAPC). Results: Between 1999 and 2024, a total of 208,476 AAA-related deaths among U.S. adults aged ≥ 65 years were recorded. Overall AAMR declined significantly from 32.61 per 100,000 population in 1999 to 12.17 per 100,000 population in 2024 (AAPC −3.86%; 95% confidence interval [CI]: −4.43 to −3.30; p < 0.001). Mortality rates remained consistently higher among males, adults aged ≥ 85 years, non-Hispanic White individuals, residents of the Midwest, and non-metropolitan populations. Joinpoint analysis demonstrated sustained declines across most demographic groups. Although several subgroups exhibited a temporary plateau in declining mortality trends during the pandemic era, these trend changes did not reach statistical significance. Following 2021, mortality rates resumed a significant downward trend. Conclusions: AAA-related mortality among U.S. adults aged ≥ 65 years declined substantially between 1999 and 2024; however, important demographic and geographic disparities persist. Continued efforts aimed at risk factor reduction, equitable screening access, and preventive vascular care remain essential to further reduce AAA-related mortality among older adults.

Background: Coronary artery disease (CAD) and depression frequently coexist and may synergistically worsen outcomes through behavioral, inflammatory, and neuroendocrine mechanisms. However, national mortality trends involving both conditions remain incompletely characterized.Objective: To evaluate temporal trends and demographic disparities in mortality involving CAD and depression in the United States from 1999–2025.Methods: We conducted a retrospective population-based study using the CDC WONDER Multiple Cause of Death database. Adults aged ≥25 years with ICD-10 codes for CAD (I20–I25) and depression (F32, F33, F41.2) listed anywhere on the death certificate were identified. Age-adjusted mortality rates (AAMRs) per 100,000 population were standardized to the 2000 U.S. population. Joinpoint regression was used to estimate annual percent change (APC) and average annual percent change (AAPC), with analyses stratified by age, sex, race/ethnicity, geographic region, urbanization, and state.Results: A total of 85,806 deaths were identified, with an overall average AAMR of 1.42. Mortality declined from 1.81 (95% CI, 1.75–1.87) in 1999 to 1.31 (95% CI, 1.26–1.35) in 2025 (AAPC, −1.38; p=0.002), although rates increased significantly between 2017 and 2020. Mortality was highest among older adults but increased among middle-aged adults (AAPC, 1.10; p<0.001). Males had higher mortality than females. The Midwest had the highest regional burden, while the South showed no significant overall improvement. Mortality increased among Black individuals after 2014 and remained higher in nonmetropolitan areas.Conclusions: Mortality involving CAD and depression declined overall but remained heterogeneous, with persistent racial and geographic disparities and rising mortality among middle-aged adults.