Comparison of the urinary metabolite profile of caffeine in young and elderly males.

Abstract

The urinary metabolite profile of caffeine was compared in a group of seven healthy young men aged 18‐29 years and in a group of five healthy elderly men aged 66‐71 years. All subjects were given 5 mg/kg doses of caffeine as an aqueous oral solution or an intravenous infusion on two separate occasions in a randomized crossover design. Urine samples were collected for 24 h after dosing and analysed for caffeine and eleven of its metabolites by high‐performance liquid chromatography. The effects of age, route of administration, and order of administration by route on the metabolite profile of caffeine were examined. The route of administration and the order of administration by the two routes were found not to influence the urinary metabolite pattern significantly. The urinary metabolite profile did not vary substantially with age except for the observation that significantly greater amounts of 1‐ methyluric acid, 7‐methyluric acid and 1,7‐dimethyluric acid were excreted by the elderly subjects.

Urine Excretion of Caffeine and Select Caffeine Metabolites Is Common in the US Population and Associated with Caffeine Intake

“…The association of age, sex, and race-ethnicity with caffeine metabolism is not straightforward; however, there is some evidence suggesting that these demographic factors may have limited influence on biomarker behavior. Age has been shown in males to have no significant effect on peak plasma concentration, time to reach peak concentration, or half-life of caffeine metabolites (29,30), although urine excretion of 17U, 1U and 7U was statistically higher in older subjects (31). No sex-based differences in caffeine metabolism have been observed based on urine metabolites and metabolite ratios (32), although CYP1A2 activity, which affects multiple stages of caffeine metabolism, has been shown to be higher in men vs. women (33).…”

Estimation of caffeine intake from analysis of caffeine metabolites in wastewater

“…1.47 1.87 (Scott et al, 1986) (Grant et al, 1983) 300 mg 68 24 6 1.9 (Blanchard et al, 1985) (Grant et al, 1983) 300 mg 68 24 1.1 0.6 (Blanchard et al, 1985) 5 mg/kg 5 (elderly) 7 (young) 24 * (Senta et al, 2015) …”

“…Precursor and products ions of the analyzed compounds with the associated collision energies Table S4. Linearities, recoveries, repeatibilities and quantification limits 4 Dan-Shya et al, 1983) Theophylline (7.5 mg/kg) and caffeine (7.5 mg/kg) 2 weeks later 6 60 7.1 1.7 (Callahan et al, 1982) (Grant et al, 1983) 300 mg 68 24 4.8 2.4 (Blanchard et al, 1985) 5 mg/kg 5 (elderly) 7 (young) 24 3.37 3.49…”

Urinary caffeine metabolites in man

“…The incomplete solubility of 1 U in acidified solvents then realised, which would account for the differences in findings obtained by the original method, and the great variability of 1 U-excretion reported in many previous studies [9,13,26,27,32]. The incomplete solubility of 1 U in acidified solvents then realised, which would account for the differences in findings obtained by the original method, and the great variability of 1 U-excretion reported in many previous studies [9,13,26,27,32].…”

“…However, the possi-* Present address: Department of Ear, Nose, Throat Diseases, University of G6ttingen, Robert-Koch-Strasse, W-3400 G/3ttingen, FRG ** Present address: Dean, Medical Faculty, University of Witten/Herdecke, Beckweg 4, W-5804 Herdecke, FRG bilities of noninvasive measurement of those enzyme activities have been limited until now [4,5]. Caffeine is safe, its metabolism results from the activity of multiple enzymes and its major metabolites can now be measured in urine [6][7][8][9][10][11][12][13]. Caffeine is safe, its metabolism results from the activity of multiple enzymes and its major metabolites can now be measured in urine [6][7][8][9][10][11][12][13].…”