In contrast, elevated serum alkaline phosphatase or reduced albumin did not provide a satisfactory explanation for the lower plasma pyridoxal 5'-phosphate level in rheumatoid arthritis, because the presence of disease remained a significant determinant of plasma pyridoxal 5'-phosphate concentrations after adjustment for serum alkaline phosphatase and albumin concentrations [34]. Here, ALB is linked to rheumatoid arthritis.