Facial acne scarring is a widely prevalent dermatological disease manifested as a permanent aftereffect of acne vulgaris. While fractional CO₂ laser and needling procedures are essential to treating atrophic acne scars, comparative and safety data remains limited. This systematic review and meta-analysis directly compares their efficacy and safety. According to PRISMA guidelines, PubMed, Cochrane, Google Scholar, and ClinicalTrials.gov were systematically searched. Only studies comparing fractional CO₂ laser with needling-based monotherapy treating facial atrophic acne scars in adults were included. A random-effects model was employed for meta-analysis using Review Manager (RevMan) to compare efficacy and safety outcomes. A total of 17 studies were included in the meta-analysis. For primary efficacy outcomes, the results were non-significant for mean scar score reduction (SMD: -1.08, 95% CI: [-2.48, 0.32], I² = 97%) or mean quantitative scar reduction (SMD: 0.12, 95% CI: [-0.80, 1.04], I² = 92%), with significant heterogeneity. However, categorical treatment success was significantly high for CO₂ laser (RR: 1.10, 95% CI: [1.01, 1.20], I² = 0%). For safety outcomes, fractional CO₂ laser showed significantly high risk of post-inflammatory hyperpigmentation (PIH) as compared to standard microneedling (RR: 3.04, 95% CI: [1.49, 6.21], I² = 3%), but showed significantly low pain scores as compared to RF microneedling (SMD: -0.74, 95% CI: [-1.27, -0.21], I² = 0%). No significant differences were found for erythema, crusting/scabbing, or edema. Both fractional CO₂ laser and microneedling procedures show comparable efficacy in treating atrophic acne scars, however, patient variables such as skin type, scar type, and possible complications should be taken into consideration. Moreover, further tailored therapies are crucial to treating acne scars with low risk for complications.

Atrial fibrillation (AF)/flutter and renal dysfunction commonly coexist and are associated with substantial cardiovascular and thromboembolic risk. Despite this clinical overlap, national mortality patterns among individuals whose death certificates record both conditions have not been well characterized over an extended period. We examined changes over time in deaths documenting both AF/flutter and renal failure and assessed whether these patterns differed across demographic and geographic groups among U.S. adults aged ≥ 45 years from 1999 to 2023. We queried the Centers for Disease Control and Prevention Wide-ranging Online Data for Epidemiologic Research Multiple-Cause-of-Death database for death certificates of U.S. adults aged ≥ 45 years in which AF/flutter (International Classification of Diseases, Tenth Revision I48) and renal failure (N17–N19) were both recorded. Either diagnosis could appear as the underlying or a contributing cause of death. Mortality rates were age-standardized to the 2000 U.S. population and expressed per 100,000 persons. Joinpoint regression was used to evaluate changes in annual age-adjusted mortality rates and to estimate annual percentage changes (APCs). The study included 392,927 death certificates meeting these criteria. The age-adjusted mortality rate increased from 6.3 per 100,000 in 1999 to 20.6 per 100,000 in 2023. Significant upward trends occurred during 1999 to 2012 (APC, 6.21%) and 2015 to 2023 (APC, 9.62%). Rates were higher among men than women throughout the study period. In 2023, the age-adjusted mortality rate was 22.55 per 100,000 among non-Hispanic White individuals, 19.91 among non-Hispanic Black or African American individuals, 14.31 among non-Hispanic American Indian or Alaska Native individuals, 11.75 among Hispanic or Latino individuals, and 10.28 among non-Hispanic Asian or Pacific Islander individuals. The age-adjusted mortality rate for deaths documenting both AF/flutter and renal failure increased markedly among U.S. adults aged ≥ 45 years between 1999 and 2023. The magnitude of this mortality pattern differed by sex, race/ethnicity, and geographic location. Because the analysis is based on diagnoses documented on death certificates, the findings reflect population-level co-documentation of the 2 conditions and do not establish that either condition, alone or in combination, directly caused death. Individual-level studies are needed to determine the clinical and healthcare factors associated with these trends.