Examining the prevalence of sarcopenic obesity and its association with frailty in community-dwelling middle aged and older females
Sarcopenic obesity is the co-existence of low muscle mass and excess fat mass and can place frail individuals at increased risk of disability, chronic diseases, and mortality. Due to a lack of standardized criteria, the prevalence of sarcopenic obesity varies across definitions. The purpose of this cross-sectional study is to determine the prevalence of sarcopenic obesity using different published diagnostic criteria and its association with frailty in a population of Manitoba females, aged 55 years and older. Further, the prevalence of sarcopenic obesity and its association with frailty with the addition of handgrip strength (HGS) stratified by Body Mass Index (BMI) to sarcopenic obesity diagnostic criteria was examined to determine if the inclusion of HGS as part of existing diagnostic criteria strengthens the association between sarcopenic obesity and frailty. Finally, the relationship between BMI, waist circumference (WC) and frailty were explored to determine if a U-shaped relationship was observed in the study cohort. The relationship between Percentage Body Fat (%BF), WC, and frailty was also explored to determine if %BF exhibits a similar relationship with frailty compared to BMI. Diagnostic criteria were selected for analysis if body composition was measured using Bioelectric impedance analysis (BIA) and sex-specific (female) cut-off values were included. 20 diagnostic criteria were considered for analysis. The association between frailty and sarcopenic obesity was determined using a Spearman’s correlation. An unpaired t-test was performed in any models that were correlated in order to compare the frailty index scores between sarcopenic obesity levels. The prevalence of sarcopenic obesity ranged from 0% - 39%. Sarcopenic obesity was only significantly associated with frailty when using weight-adjusted or unadjusted diagnostic criteria, whereas there was no difference in frailty index scores in height-adjusted definitions. The addition of HGS lowered the prevalence of sarcopenic obesity in this cohort, ranging from 0%-5% and did not change the association with frailty in any criteria that did not already demonstrate an association. Lastly, a U-shaped relationship was not observed in this cohort, however, frailty index scores were higher in those within the top two BMI (30.1-35 kg/m2 and >35kg/m2) and top two %BF (37-41.7% and >41.8%) categories in the high WC group. This research expands the understanding of current sarcopenic obesity published diagnostic criteria and their association with frailty. The research revealed that weight-adjusted sarcopenic obesity criteria detect differences in frailty. Further, this thesis demonstrated that the inclusion of HGS in criteria did not improve the association between sarcopenic obesity and frailty. Finally, the cohort did not have a U-shaped relationship between frailty and BMI, or frailty and %BF in either low or high WC groups.