Isotope dilution gamma spectrometry (IDGS) for determination of the Pu concentration, using high resolution gamma-ray spectrometry (HRGS) in the 40–150 keV energy range, is developed and described. The methodology involves purification of Pu by an anion exchange procedure, followed by the determination of Pu isotopic composition using HRGS. For isotope dilution, a pre-calibrated power reactor grade Pu (∼ 70 at. % 239Pu) solution from an Indian PHWR was used as a spike for research reactor grade Pu (∼ 95 at. % 239Pu) samples and vice versa. Changes in 240Pu/239Pu (45.24 keV/51.62 keV) and 241Pu/239Pu (148.57 keV/129.29 keV) activity ratios in the spiked samples were determined by gamma spectrometry. Using the atom ratios calculated from the measured activity ratios, the concentration of Pu in the sample was calculated using two different efficiency calibration methods. The isotopic composition and concentration of Pu samples both from power reactor and research reactor grade agreed well with the values obtained by isotope dilution-thermal ionization mass spectrometry. The present method also shows the superiority of using the 240Pu/239Pu atom ratio against the 241Pu/239Pu atom ratio in IDGS with respect to the accuracy and precision.
Non-adherence to diabetes medication leads to poor outcomes and increased healthcare costs. Multiple factors affecting adherence in adults with type 2 diabetes (T2D) have been identified, but pediatric data is sparse. We aimed to determine whether initiation of additional oral medications or insulin affects adherence to primary study medication (PSM) in the Treatment Options for type 2 Diabetes in Adolescents and Youth (TODAY) study.
Six hundred and ninety-nine youth (aged 10–17 years) with recent-onset T2D were randomized in the TODAY study. Participants were categorized as adherent (≥80% taken by pill count) or non-adherent (<80%), and adherence was compared between those on additional medications or not. Subgroup analyses to assess influence of race/ethnicity, gender, medication type, or depression were performed.
At 36 months, 46.3% of participants were taking additional oral medications and 31.9% were on insulin. There was no difference in study medication adherence with additional oral medications (55.1%, 67.1%, and 56.7% at month 36 in those prescribed 0, 1, or 2+ additional medications; p = 0.16). Girls on oral contraceptives (OC) had higher adherence (65.2% vs. 55.8% at month 36; p = 0.0054). Participants on insulin had lower adherence (39.7% vs. 59.3% at 36 months; p < 0.0001). There was decreased adherence in participants with baseline depression (p = 0.008).
Additional oral medications did not influence adherence to diabetes medications in TODAY. Addition of insulin led to reduced adherence. In subgroup analyses, OC use was associated with higher adherence in girls, while baseline depression was associated with lower adherence overall. Further studies examining potentially modifiable risk factors of adherence in pediatric T2D are needed.