The relationship between thumb adductor muscle thickness, fat-free mass and muscle strength in hospitalized adults

Abstract

Introduction: the measurement of thumb adductor muscle thickness (TAMT) is a new technique for evaluating muscle mass during hospitalization.

Objective: to determine the relationship between TAMT, fat-free mass (FFM) and muscle strength (MS) in adults hospitalized at Hospital Universitario Nacional de Colombia (HUN).

Materials and methods: this was an observational, cross-sectional, analytical study. A total of 157 patients were included during 2018 and 2019. Socioeconomic and clinical variables were evaluated, along with TAMT, anthropometry, FFM and MS. The statistical analysis included measures of central tendency, correlation, ROC curves for TAMT cut-off points, and multiple and logistic regression.

Results: the study population was 61% male and 39% female; the average age was 63.3±17.0 years; 75% were over the age of 60. The majority (44%) were pre-obese and obese. The TAMT in the dominant hand (TAMTD) was 17±3.7 mm. In men, the average value was 18±3.4 mm, and in women it was 15.3±3.6 mm; for those under the age of 60, the average was 18.1±3.3 mm and for those over the age of 60, the average was 16.6±3.8 mm. A TAMTD less than 13.4 mm was considered undernutrition. The relationship between TAMTD and FFM showed a significant association (r =0.45), but TAMTD is not a predictor of FFM. Muscle strength and FFM had a significant correlation (r = 0.69); however, MS does not predict FFM. A significant correlation was found between TAMTD and MS (r = 0.53), but TAMTD is not a predictor of MS.

Conclusions: most of the patients were overweight. The TAMT was greater in the dominant hand and in men, decreased with age and predicted undernutrition. There was a significant, but not predictive, association between MS and FFM. The TMAT was significantly associated with FFM and MS but is not a useful predictor of these variables.