Sarcopenia index based on serum creatinine and cystatin C is associated with 3-year mortality in hospitalized older patients

Abstract

To investigate the association of the sarcopenia index (SI, serum creatinine value/cystatin C value × 100) with 3-year mortality and readmission among older inpatients, we reanalyzed a prospective study in the geriatric ward of a teaching hospital in western China. Older inpatients aged ≥ 60 years with normal kidney function were included. Survival status and readmission information were assessed annually during the 3-year follow-up. We applied Cox regression models to calculate the hazard ratio (HR) and 95% confidence intervals (CIs) of sarcopenia for predicting mortality and readmission. We included 248 participants (mean age: 81.2 ± 6.6 years). During the follow-up, 57 participants (23.9%) died, whereas 179 participants (75.2%) were readmitted at least one time. The SI was positively correlated with body mass index (BMI) (r = 0.214, p = 0.001), calf circumference (CC) (r = 0.253, p < 0.001), handgrip strength (r = 0.244, p < 0.001), and gait speed (r = 0.221, p < 0.001). A higher SI was independently associated with a lower risk of 3-year all-cause mortality after adjusting for potential confounders (HR per 1-SD = 0.80, 95% CI: 0.63-0.97). The SI was not significantly associated with readmission (HR per 1-SD = 0.97, 95% CI: 0.77-1.25). In conclusion, the SI is associated with 3-year all-cause mortality but not readmission in a study population of hospitalized older patients.

Serum creatinine/cystatin C ratio as a case-finding tool for low handgrip strength in Chinese middle-aged and older adults

“…Moreover, we recently found that the sarcopenia index was correlated with handgrip strength (r 2 = 0.24, p < 0.001) among older Chinese inpatients 15 . A more recent report has indicated that handgrip strength in 677 community-dwelling older Japanese adults was correlated with the Cr/CysC ratio 16 .…”

Towards Personalized Management of Sarcopenia in COPD

“…Moreover, Hirai et al 71 demonstrated that the Cr/CysC may serve as a surrogate marker for sarcopenia in COPD, with a cut-off of 0.71 in male patients. However, Tang et al 72 recently suggested that the Cr/CysC ratio could only serve as a potentially valuable biomarker to predict adverse outcomes in elderly, but not necessarily as a surrogate marker for sarcopenia, since other factors, such as chronic kidney disease, 73 a frequent comorbidity in COPD patients, 74 might also influence serum Cr levels. Therefore, although serum Cr and CysC can be easily determined in clinical practice, better validation is required before this can be applied in clinical practice.…”

“…Therefore, although serum Cr and CysC can be easily determined in clinical practice, better validation is required before this can be applied in clinical practice. 72 • In the search for reliable biomarkers to reflect muscle damage, urinary titin, a sarcomeric protein that is excreted in urine, has been investigated and was found to correlate with blood markers of muscle damage. 75 More recently, elevated levels of urinary titin were demonstrated to correlate with rectus femoris muscle atrophy in intensive care patients.…”

Association between self‐reported appetite and clinical outcomes of peritoneal dialysis patients: Findings from a low middle‐income country

“…Although there was no statistical or numerical difference in baseline serum albumin across levels of appetite in the current study, it is possible that baseline serum albumin was not sensitive enough to differentiate nutritional status, and using time‐average serum albumin may have better reflected dialysis‐associated malnutrition. Nonetheless, a progressive decrease in serum creatinine with poorer appetite suggested a higher prevalence of sarcopenia in poor appetite patients 28,29 . Given the similar body mass index, lower serum creatinine also raises the possibility of subclinical overhydration in the poor appetite group, preceding overt malnutrition 30 .…”