[15O]water pharmacokinetics: influence of age and gender in normal subjects

To compile a normal database for the characterization of global [15O]water pharmacokinetic behavior.

The influences of age, gender, and body habitus on the pharmacokinetics of [15O]water were investigated in a series of normal subjects, N = 100 (50 males, 50 females, age = 19-79) who were participants in cognitive activation studies. Arterial blood was analyzed by autosampler and parametric images were constructed using a 40-second summed image and the autoradiographic model.

Males and females were comparable with respect to age, number of injections administered, and dose (mCi) administered per injection but differed significantly with respect to height, weight, and normalized dose (mCi/kg). There were significant gender-based differences in the bolus arrival time, global cerebral blood flow (gCBF), area-under-the-curve (AUC), summed image concentration, and dose-normalized concentration but not dose-normalized AUC. Bolus arrival time, gCBF and dose-normalized AUC were significantly influenced by age.

Age and gender are significant determinants of [15O]water pharmacokinetic behavior.