Association of visceral fat area with pre-frailty in Japanese community-dwelling older adults: a cross-sectional study.

BACKGROUND: Screening and intervention in pre-frailty can help prevent or delay frailty among older adults. Being overweight has shown associated with pre-frailty, and overweight is highly prevalent among community-dwelling older adults during COVID-19. However, the impact of visceral fat accumulation remains unclear. This study aimed to explore the association between visceral fat area and pre-frailty in community-dwelling older adults. METHODS: The participants of this study included community-dwelling older adults from three elderly welfare centers. The frailty phenotype was assessed using the frailty screening index. The body composition was measured using bioelectrical impedance analysis. RESULTS: A total of 214 community-dwelling older adults completed the questionnaire and measurements. After excluding 16 frail participants, 149 (75.3%) were pre-frailty. The mean age of participants was 75.4 ± 5.4 years, and 69.7% (138) of participants were women. There were 54 (27.3%) participants with high visceral fat area. The multivariable model showed that participants with high visceral fat area were at increased risk for pre-frailty (adjusted OR, 3.15; 95% CI, 1.26 - 7.87; P = 0.014), even after adjusted for age, sex, health status, and impact of COVID-19 pandemic. CONCLUSIONS: This study suggests that the association between visceral fat accumulation and pre-frailty may help to identify a new target for prevention. Further longitudinal studies are needed to determine their mechanisms in older adults.

Computed tomography-defined body composition as prognostic markers for unfavourable outcomes and in-hospital mortality in coronavirus disease 2019.

BACKGROUND: Low skeletal muscle mass (LSMM) and visceral fat areas can be assessed by cross-sectional images. These parameters are associated with several clinically relevant factors in various disorders with predictive and prognostic implications. Our aim was to establish the effect of computed tomography (CT)-defined LSMM and fat areas on unfavourable outcomes and in-hospital mortality in coronavirus disease 2019 (COVID-19) patients based on a large patient sample. METHODS: MEDLINE library, Cochrane, and Scopus databases were screened for the associations between CT-defined LSMM as well as fat areas and in-hospital mortality in COVID-19 patients up to September 2021. In total, six studies were suitable for the analysis and included into the present analysis. RESULTS: The included studies comprised 1059 patients, 591 men (55.8%) and 468 women (44.2%), with a mean age of 60.1 years ranging from 48 to 66 years. The pooled prevalence of LSMM was 33.6%. The pooled odds ratio for the effect of LSMM on in-hospital mortality in univariate analysis was 5.84 [95% confidence interval (CI) 1.07-31.83]. It was 2.73 (95% CI 0.54-13.70) in multivariate analysis. The pooled odds ratio of high visceral fat area on unfavourable outcome in univariate analysis was 2.65 (95% CI 1.57-4.47). CONCLUSIONS: Computed tomography-defined LSMM and high visceral fat area have a relevant association with in-hospital mortality in COVID-19 patients and should be included as relevant prognostic biomarkers into clinical routine.

Visceral adiposity, subcutaneous adiposity, and severe coronavirus disease-2019 (COVID-19): Systematic review and meta-analysis.

BACKGROUND AND AIMS: Body mass index (BMI) has previously been shown to increase mortality and disease severity in patients with COVID-19, but the pooled effect estimate was heterogeneous. Although BMI is widely used as an indicator, it cannot distinguish visceral from subcutaneous fat. This systematic review and meta-analysis aimed to investigate the association between visceral adiposity, subcutaneous fat, and severe COVID-19. METHODS: We performed a systematic literature search using the databases: PubMed, Embase, and EuropePMC. Data on visceral fat area (VTA), subcutaneous fat area (SFA), and total fat area (TFA) were collected. The outcome of interest was severe COVID-19. We used a REML random-effects model to pool the mean differences and odds ratio (OR). RESULTS: There were 5 studies comprising of 539 patients. Patients with severe COVID-19 have a higher VTA (mean difference 41.7 cm2 [27.0, 56.4], p < 0.001; I2: 0%) and TFA (mean difference 64.6 cm2 [26.2, 103.1], p = 0.001; I2: 0%). There was no significant difference in terms of SFA between patients with severe and non-severe COVID-19 (mean difference 9.3 cm2 [-4.9, 23.4], p = 0.199; I2: 1.2%). Pooled ORs showed that VTA was associated with severe COVID-19 (OR 1.9 [1.1, 2.2], p = 0.002; I2: 49.3%). CONCLUSION: Visceral adiposity was associated with increased COVID-19 severity, while subcutaneous adiposity was not. PROSPERO ID: CRD42020215876.