title: The importance of creatinine flow, age and 24 h urinary output in the interpretation of the MHPG flow.
abstract: The 3-methoxy-4-hydroxyphenylglycol (MHPG) flow, the creatinine flow in 24 h urine and the plasma creatinine level were determined in 42 psychiatric control patients. The creatinine clearance was calculated. The relationship between MHPG flow in 24 h urine and creatinine clearance, creatinine flow, 24 h urinary output, age, sex and weight of the patient were studied by means of single and multiple regression methods. The MHPG flow was significantly correlated with creatinine clearance (r = 0.597), creatinine flow (r = 0.646) and sex of the patient (rpb = 0.434). The variance of the MHPG flow can be explained by the regression with creatinine flow, age and urinary output for a maximum 51.5%. These variables have to be taken into account for the interpretation of data concerning the MHPG flow in subsequent experimental designs. The results of the measurements of the MHPG flow can best be expressed as the residual values obtained after partialling out the predictable component calculated by multiple regression with creatinine flow, age and 24 h urine output.
mesh_terms: D000328:Adult; D000367:Age Factors; D003404:Creatinine / Q000097:blood / Q000378:metabolism* / Q000652:urine; D005260:Female; D005919:Glomerular Filtration Rate; D006018:Glycols / Q000378:metabolism*; D006801:Humans; D008297:Male; D001523:Mental Disorders / Q000378:metabolism*; D008734:Methoxyhydroxyphenylglycol / Q000378:metabolism*; D012107:Research Design; D012737:Sex Factors
chemical_list: D006018:Glycols; D008734:Methoxyhydroxyphenylglycol; D003404:Creatinine