Translation and validation of the Korean version of the Sarcopenia Quality of Life (SarQoL-K®) questionnaire and applicability with the SARC-F screening tool.

PURPOSE: The purpose of this paper was to translate and validate into the Korea language and setting the Sarcopenia Quality of Life (SarQoL®) questionnaire. METHODS: The participants consisted of 450 individuals in Namgaram-2 cohort who were followed up in 2019-2020. The study participants were divided into four groups: (1) SARC-F < 4, (2) SARC-F ≥ 4 and robust grip strength, (3) SARC-F ≥ 4, low grip strength, robust muscle mass, (4) SARC-F ≥ 4, low grip strength, and low muscle mass. To assess construct validity, population with sarcopenia-associated symptoms (SARC-F ≥ 4) apart from the Korean SarQoL (SarQoL-K®) completed the Korean versions of two generic questionnaires, the Short Form-36 and the EuroQoL 5-dimension. To validate the Korean SarQoL®, we assessed its validity (discriminative power, construct validity), reliability (internal consistency, test-retest reliability), and floor/ceiling effects. RESULTS: The SarQoL-K® questionnaire was translated without major difficulties. The mean SarQoL-K scores were 72.9 (95%, CI; 71.2-74.6) in SARC-F < 4, 54.6 (95%, CI; 50.7-58.3) in SARC-F ≥ 4 and robust grip strength, 47.0 (95%, CI; 43.8-50.1) in SARC-F ≥ 4, low grip strength, robust muscle mass, 46.6 (95%, CI; 43.0-50.1) in SARC-F ≥ 4, low grip strength, and low muscle mass. The results indicated good discriminative power across each four groups (p < 0.001), high internal consistency (Cronbach's alpha of 0.866), and excellent test-retest reliability (ICC = 0.977, 95% CI 0.975-0.979). No floor- or ceiling-effects were observed. CONCLUSIONS: This is the first study to confirm the reliability and validity of the Korean version of the SarQoL®. We demonstrated that the population with sarcopenia-associated symptoms (determined using the SARC-F questionnaire) has a lower quality of life.

Exercise training increases skeletal muscle strength independent of hypertrophy in older adults aged 75 years and older.

AIM: We investigated whether exercise-mediated acquisition of muscle mass and strength would occur in a concurrent manner in older adults. METHODS: A total of 152 community-dwelling older adults (young-old aged 65-74 years, old-old aged >75 years) were allocated into either 8-week comprehensive exercise training or the control group. Participants (n = 136) completed all pre- and post-intervention testing visits (young-old n = 73, old-old n = 63). Older adults in exercise groups were subjected to a series of programmed elastic band and free exercises twice per week at three to five sets of 15-20 repetitions. Body composition, skeletal muscle mass, knee strength (extensors and flexors) and gait-related physical function were evaluated as main variables. RESULTS: As expected, muscular mass and knee strength (both extensors and flexors) were inversely correlated with age in the old-old group (all P < 0.001). However, knee extensor strength was the only lower limb component inversely correlated with age in the young-old group (P < 0.043). Knee extensor strength was significantly increased by exercise training in both the young-old and old-old groups (young old P < 0.042, old-old P < 0.011). Training-induced muscle hypertrophy was observed only in the young-old group (P < 0.025). the correlation of knee extensor strength against gait-related physical function was the greatest, followed by knee flexor strength and muscle mass. CONCLUSIONS: The present results showed that age-associated strength decline of the knee extensor occurs earlier compared with the knee flexor during the aging process, and exercise training increases muscular strength without significant changes of muscle mass in older adults aged aged ≥75 years. Geriatr Gerontol Int 2019; 19: 265-270.