Paravertebral Myosteatosis is Associated with 1-Year Mortality in Older Adults Hospitalized for Covid-19 Infection

Rationale: Sarcopenia has emerged as a predictor of poor outcomes in COVID-19 patients, but the predictive value of muscle quality, i.e. fat infiltration of the muscle (myosteatosis) on subsequent mortality has been rarely assessed in older adults. The aim of this study was to determine if myosteatosis was associated with 1-year mortality in hospitalized older adults with COVID-19 infection. Methods: This is an ancillary study of a multicenter retrospective study that included adults aged ≥70, hospitalized for COVID-19 in 13 geriatric acute care wards. We included patients with a thoracic CT-scan performed within 5 days after the diagnosis in two centers. Paravertebral muscle data were measured at T12 level: skeletal muscle mass index and the severity of myosteatosis using the Goutallier classification (five-level visual scale ranging from 0 (no myosteatosis) to 4 (very severe myosteatosis)). Cox model evaluated the associations of clinical and thoracic imaging data with 1-year mortality. Results: Among the 90 participants (46% women, mean age 84 years), 29 (32%) died within one year. The lung COVID-19 injury severity and the severity of paravertebral myosteatosis were associated with 1-year mortality. In contrast, the skeletal muscle index was not associated with survival. In Cox model adjusted on lung injury severity, hypertension, obesity and Charlson comorbidity index, the most severe degrees of myosteatosis were associated with 1-year mortality: HR (95% CI) for Goutallier classification 3-4 vs 0-1, 2.46 [1.20 - 6.48], p=0.01. Conclusion: The myosteatosis was independently associated with 1-year mortality in older adults hospitalized for COVID-19. Muscle quality, and not only muscle mass, should be considered in older adults. The Goutallier classification is an easy-to-use, visual method to quantify myosteatosis, yet to be evaluated in other clinical situations and populations. Disclosure of Interest: None declared