Relationship Between Clinical Symptoms and Skin Autofluorescence in Hemodialysis Patients as a Measure of Advanced Glycation End-Product Accumulation

Background The purpose of this study was to investigate the relationship between skin autofluorescence (SAF), as a measure of advanced glycation end-product (AGE) accumulation and osteoporosis and clinical symptoms in hemodialysis patients. Methodology The study participants were 156 hemodialysis patients (97 males, 59 females, mean = 66.9 years, range = 25-92 years) who visited our hospital between October 2019 and March 2020. The average dialysis period was 10.4 years (range = 1-40 years). Age, years of dialysis, bone mineral density, bone metabolism markers (Ca, P, intact parathyroid hormone, total N-terminal propeptide of type 1 collagen, tartrate-resistant acid phosphatase-5b), clinical symptoms, and SAF were evaluated. Clinical symptoms were evaluated using the visual analog scale (VAS) score for low back pain (LBP) and leg pain ranging from 10 mm (extreme amount of pain) to 0 mm (no pain); the Japanese Orthopaedic Association Back Pain Evaluation Questionnaire (JOABPEQ; 0-100 points); and the Roland-Morris Disability Questionnaire (RDQ; 0-24 points). We calculated Pearson correlation coefficients to assess the correlation of SAF with age, years of hemodialysis, bone density, bone metabolism markers, clinical symptoms, and biochemical markers. Results The SAF of dialysis patients averaged 4.11, higher than previous reports for non-dialysis patients. Age (r = 0.435, p = 0.0001) was moderately positively correlated and hemodialysis period (r = 0.214, p = 0.00907) was weakly positively correlated with SAF. Among the clinical symptoms measured by the JOABPEQ, social life dysfunction (r = -0.257, p = 0.0108) had a weak negative correlation with SAF. Conclusions The level of AGEs implied by SAF was elevated in hemodialysis patients. SAF correlated with social life disorders, suggesting that SAF may be involved in disorders of activities of daily living in hemodialysis dialysis patients.