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The following is a summary of “Exploring the association between computed tomography (CT)-derived skeletal muscle mass and short- and long-term mortality in critically ill patients: a systematic review and meta-analysis,” published in the June 2025 issue of Critical Care by Maluf et al. 

Low skeletal muscle mass, commonly observed at hospital admission, has been linked to unfavorable outcomes.  

Researchers conducted a retrospective study to examine the relationship between computed tomography (CT)–derived skeletal muscle mass at the lumbar level and both short- and long-term mortality in patients with critical illness.  

They followed PRISMA 2020 guidelines to include studies of adults with critical illness (≥ 18 years) admitted to intensive care units (ICU) that measured CT–derived skeletal muscle mass at the lumbar vertebral level within ± 7 days of admission. Mortality was the primary outcome, divided into short-term (ICU, hospital, 28- and 30-day) and long-term (> 30 days) categories, MEDLINE and Embase were searched without date limits. Screening was done using Rayyan, data extraction by a custom tool, and quality was assessed using the JBI Cohort Study Checklist. Meta-analyses were performed on studies reporting mortality by muscle mass status and on the prevalence of low muscle mass subgroups.  

The results showed that out of 1,248 unique records, 35 studies met inclusion criteria, involving 9,366 participants. Most of the studies were across 4 continents, including varied populations such as patients with sepsis, COVID-19, and trauma. Sample sizes ranged from 36 to 939, with ages mostly between 40 and 70 years and 62% male predominance. Skeletal muscle mass was primarily measured as skeletal muscle index at the third lumbar vertebra. Short-term mortality was mainly reported at 28 or 30 days, while 11 studies assessed long-term mortality at 90 days, 6 months, or 1 year. A meta-analysis found low skeletal muscle mass area and index significantly increased risks of short-term mortality (OR = 2.33, CI 1.90–2.87, I²  = 41.39%) and long-term mortality (OR = 2.67, CI 1.45–4.92, I²  = 62.24%). The overall prevalence of low muscle mass was 42% (CI 34–49%, I²  = 98.2%).  

Investigators concluded that CT-assessed skeletal muscle mass at the lumbar level on ICU admission was associated with short- and long-term mortality and could serve as a prognostic marker. 

Source: ccforum.biomedcentral.com/articles/10.1186/s13054-025-05427-2