Malnutrition is a major contributor to muscle loss and muscle dysfunction, known as sarcopenia. Malnutrition is common in patients with inflammatory bowel disease (IBD). IBD includes ulcerative colitis (UC) and Crohn’s disease (CD). The number of patients with IBD has recently been increasing. More severe malnutrition is often seen in CD compared to UC, probably due to CD affecting the main site of nutrient absorption, extensive mucosal lesions, fistulas, short bowel syndrome after resection, or obstruction of the gastrointestinal tract. A recent meta-analysis showed the high prevalence of sarcopenia in patients with IBD, and thus sarcopenia is a very important problem for IBD. Although IBD is more common in younger patients, sarcopenia can develop through a variety of mechanisms, including malnutrition, chronic inflammation, increased inflammatory status in adipose tissue, vitamin deficiency, and imbalance of the muscle–gut axis. In addition, sarcopenia has a negative impact on postoperative complications and hospital stay in patients with IBD. Appropriate intervention for sarcopenia may be important, in addition to clinical remission and endoscopic mucosal healing in patients with IBD. Much more attention will thus be paid to sarcopenia in patients with IBD. In this review, we outline IBD and sarcopenia, based on the current evidence.

Background: In recent years, various biomarkers of ulcerative colitis (UC) have emerged; however, few studies have simultaneously examined the utility of multiple biomarkers for monitoring disease activity. Additionally, serum leucine-rich alpha-2 glycoprotein (LRG), a new biomarker, may show a blunt response to anti-TNF antibody therapy. This prospective study explored effective biomarkers that could monitor disease activity changes in patients with UC. In addition, we examined the effect of anti-TNF antibody therapy on changes in LRG. Methods: Blood and stool samples were collected twice from patients with UC: at baseline and at least 8 weeks later. Changes in serum LRG, interleukin (IL)-6, prealbumin (pre-Alb), high-sensitivity C-reactive protein (hs-CRP), CRP, and fecal calprotectin (FC) were measured and correlated with changes in disease activity. The relationship between anti-TNF antibody therapy and LRG levels was also examined in patients with the same disease activity. Results: Forty-eight patients with UC (96 samples) were analyzed. ΔLRG and ΔIL-6 correlated strongly with the change in the partial Mayo (pMayo) score between the two time points (ΔpMayo) (r = 0.686, 0.635, respectively). In contrast, FC and IL-6 were particularly accurate predictors of clinical remission, and their area under the curves (AUCs) were significantly higher than that of CRP (AUC: 0.81, 0.76 vs. 0.50; p = 0.001, 0.005). No association was found between the administration of anti-TNF antibody preparations and the LRG values. Conclusions: Correlations were found between changes in UC disease activity and LRG, IL-6, pre-Alb, hs-CRP, CRP, and FC. LRG reflects disease activity during anti-TNF antibody therapy.

SARC-F is a screening tool for sarcopenia. We sought to compare the SARC-F scores of patients with different gastrointestinal diseases (n = 1282 (762 males): upper gastrointestinal disease (UGD, n = 326), lower gastrointestinal disease (LGD, n = 357), biliary and pancreatic disease (BPD, n = 416), and liver disease (LD, n = 183)). Factors associated with SARC-F ≥4 points (highly suspicious of sarcopenia) were also examined. The median age was 71 years. Patients with SARC-F ≥4 points were found in 197 (15.4%). Advanced cancer was found in 339 patients (26.4%). The proportion of SARC-F ≥4 points in groups of UGD, LGD, BPD, and LD were 17.5% (57/326) in UGD, 12.0% (43/357) in LGD, 17.3% (72/416) in BPD, and 13.7% (25/183) in LD, respectively (overall p = 0.1235). In patients with and without advanced cancer, similar tendencies were observed. In the multivariate analysis, age (p < 0.0001), gender (p = 0.0011), serum albumin (p < 0.0001), lymphocyte count (p = 0.0019), C reactive protein (p = 0.0197), and the presence of advanced cancer (p = 0.0424) were significant factors linked to SARC-F ≥4 points. In patients with advanced cancer, SARC-F scores correlated well with their Glasgow prognostic scores. In conclusion, sarcopenia in gastrointestinal diseases may be affected not by disease type (i.e., the primary origin of the disease) but by aging, nutritional condition, inflammatory condition, and cancer burden.

We sought to elucidate the prognostic impact of the SARC-F score among patients with gastrointestinal advanced malignancies (n = 421). A SARC-F score ≥ 4 was judged to have a strong suspicion for sarcopenia. In patients with ECOG-PS 4 (n = 43), 3 (n = 61), and 0–2 (n = 317), 42 (97.7%), 53 (86.9%) and 8 (2.5%) had the SARC-F score ≥ 4. During the follow-up period, 145 patients (34.4%) died. All deaths were cancer-related. The 1-year cumulative overall survival (OS) rate in patients with SARC-F ≥ 4 (n = 103) and SARC-F < 4 (n = 318) was 33.9% and 61.6% (p < 0.0001). In the multivariate analysis for the OS, total lymphocyte count ≥ 1081/μL (p = 0.0014), the SARC-F score ≥ 4 (p = 0.0096), Glasgow prognostic score (GPS) 1 (p = 0.0147, GPS 0 as a standard), GPS 2 (p < 0.0001, GPS 0 as a standard), ECOG-PS 2 (p < 0.0001, ECOG-PS 0 as a standard), ECOG-PS 3 (p < 0.0001, ECOG-PS 0 as a standard), and ECOG-PS 4 (p < 0.0001, ECOG-PS 0 as a standard) were independent predictors. In the receiver operating characteristic curve analysis on the prognostic value of the SARC-F score, the sensitivity/specificity was 0.59/0.70, and best cutoff point of the SARC-F score was two. In conclusion, the SARC-F score is useful in patients with gastrointestinal advanced malignancies.

We sought to examine the relationship between the SARC-F score and the Controlling Nutritional Status (CONUT) score in patients with gastrointestinal diseases (GDs, n = 735, median age = 71 years, and 188 advanced cancer cases). The SARC-F score ≥ 4 (highly suspicious of sarcopenia) was found in 93 cases (12.7%). Mild malnutritional condition was seen in 310 cases (42.2%), moderate in 127 (17.3%) and severe in 27 (3.7%). The median SARC-F scores in categories of normal, mild, moderate and severe malnutritional condition were 0, 0, 1 and 1 (overall p < 0.0001). The percentage of SARC-F score ≥ 4 in categories of normal, mild, moderate and severe malnutritional condition were 4.4%, 12.9%, 26.8% and 25.9% (overall p < 0.0001). The SARC-F score was an independent factor for both the CONUT score ≥ 2 (mild, moderate or severe malnutrition) and ≥5 (moderate or severe malnutrition). In the receiver operating characteristic (ROC) curve analysis for the CONUT score ≥ 2, C reactive protein (CRP) had the highest area under the ROC (AUC = 0.70), followed by the SARC-F score (AUC = 0.60). In the ROC analysis for the CONUT score ≥ 5, CRP had the highest AUC (AUC = 0.79), followed by the SARC-F score (AUC = 0.63). In conclusion, the SARC-F score in patients with GDs can reflect malnutritional status.

A certain number of patients with ulcerative colitis (UC) are refractory to anti-TNF-α antibodies; biomarkers are thus needed to predict treatment efficacy. This study aimed to evaluate whether serum biomarkers that were reported to be associated with UC or anti-TNF-α antibody could predict the response to golimumab, a human anti-TNF-α monoclonal antibody, in bio-naïve patients with UC. We prospectively enrolled 23 consecutive patients with UC who were treated with golimumab. Serum samples were collected before the first golimumab dose. Eleven molecules were measured by electrochemiluminescence (ECL) or enzyme-linked immunosorbent assay (ELISA) and their association with efficacy after 10 weeks of golimumab treatment. Among the serum biomarkers, IL-13 levels were significantly higher in the non-remission group than in the remission group (p = 0.014). IL-15 levels were significantly lower in the non-response group than in the response group (p = 0.04). For clinical remission at week 10, the IL-13 0.20 concentration of pg/mL was associated with a sensitivity and specificity of 82.4% and 83.3%, respectively. Serum IL-13 may be a biomarker to predict golimumab efficacy in biologic-naïve patients with UC, and thus may help to tailor personalized treatment strategies.