The relationship between objective measures of physical function and serum lactate dehydrogenase in older adults with cancer prior to treatment

BACKGROUND: Lactate dehydrogenase (LDH) reflects tumor burden and is a prognosticator of all-cause mortality in patients with cancer. Objective measures of physical function are associated with clinically relevant outcomes in older adults with cancer. However, whether physical function is associated with LDH in geriatric oncology is unknown. The objective of this study was to assess the relationship between objective measures of physical function and serum LDH in older adults with cancer prior to treatment. METHODS: Data from older adults with cancer prior to treatment were retrieved from an institutional database and medical records within a tertiary cancer centre. Physical function measures involved muscle strength and physical performance. Muscle strength and physical performance were assessed through grip strength and the Short Physical Performance Battery (SPPB), respectively. LDH was log transformed using the natural logarithm. Multivariable logistic regression was used to examine the relationship between objective measures of physical function and LDH prior to treatment in all participants. Stratified analyses were performed for participants with solid and hematological cancers. RESULTS: A total of 257 participants (mean age: 80.2y) were included in the analysis. Most participants were females (50.6%) and were diagnosed with locally advanced (26.8%), gastrointestinal disease (35.0%). The multivariable analysis indicated that SPPB was inversely associated with LDH in all participants (B = -0.019, 95%CI = -0.036 to -0.002, p = 0.028). Notably, the inverse relationship between SPPB and LDH persisted only in patients with hematological malignancies in the multivariable model of the stratified analysis (B = -0.049, 95%CI = -0.087 to -0.011, p = 0.013). Neither grip strength alone nor the combination of low grip strength and/or SPPB were associated with LDH. Compared to participants with metastatic disease, those with localized or locally advanced disease had lower serum LDH. CONCLUSION: Physical performance is inversely associated with serum LDH in older adults with hematological cancers prior to treatment.