Prevalence and Risk of Polypharmacy among the Elderly in an Outpatient Setting: A Retrospective Cohort Study in the Emilia-Romagna Region, Italy

Background: Polypharmacy, the simultaneous taking of many medications, has been well documented and is a topic of much concern for those looking to improve the quality of care for the elderly. Elderly patients often develop complicated and multi-factorial health states that require extensive pharmacotherapy, leaving this population at risk for exposure to drug-drug interactions and other adverse events. Previous literature supports an association between an increase in the rate of adverse events as the number of drugs taken by a patient increases. Objective: We sought to evaluate the prevalence of polypharmacy, and to determine patient characteristics that are predictive of exposure to polypharmacy, in the elderly population of the Emilia-Romagna region in Italy. Methods: We conducted a retrospective cohort study of the 2007 Emilia-Romagna outpatient pharmacy database linked with patient information available from a demographic file of approximately 1 million Emilia-Romagna residents aged ≥65 years. The cohort was comprised of 887 165 elderly subjects who had at least one prescription filled during the study year. Using the World Health Organization’s defined daily dose (DDD) to determine the duration of treatment for a given drug, we defined a polypharmacy episode as overlapping treatment with five or more medications occurring for at least one day. The prevalence of polypharmacy was measured together with subject characteristics found to be predictive of polypharmacy exposure. Results: A total of 349 689 elderly people in the population (39.4%) were exposed to at least one episode of polypharmacy during the study period. The prevalence of polypharmacy substantially increased with age and with a higher number of chronic conditions. Over 35% of those exposed to polypharmacy were exposed for 101 or more days of the year. The top three classes of medications involved in polypharmacy were antithrombotics, peptic ulcer disease and gastro-oesophageal reflux disease agents and ACE inhibitors. The odds of exposure to polypharmacy were higher for older subjects, males and subjects living in urban areas. Conclusions: This study provides evidence that the prevalence of polypharmacy in the elderly in Emilia-Romagna is substantial. Educational programmes should be developed to inform clinicians about the magnitude of the polypharmacy phenomenon and the patient characteristics associated with polypharmacy. Raising physicians’ awareness of polypharmacy may help to ensure safe, effective and appropriate use of medication in the elderly

SYZ mirror symmetry for hypertoric varieties

We construct a Lagrangian torus fibration on a smooth hypertoric variety and a corresponding SYZ mirror variety using $T$-duality and generating functions of open Gromov-Witten invariants. The variety is singular in general. We construct a resolution using the wall and chamber structure of the SYZ base.Comment: v_2: 31 pages, 5 figures, minor revision. To appear in Communications in Mathematical Physic

Initial growth behavior and resulting microstructural properties of heteroepitaxial ZnO thin films on sapphire (0001) substrates

We have investigated the initial growth behavior and resulting microstructural properties of heteroepitaxial ZnO thin films prepared by pulsed laser deposition on sapphire (0001) substrates. High-resolution x-ray diffraction and transmission electron microscopy studies revealed that the initial growth behavior and the microstructure of the films significantly depend on the growth parameters. ZnO films grown at 700 oC with 20 mTorr O2 partial pressure initiated with a columnar growth mode and contained two kinds of domains. These domains were in-plane orientated either ZnO[112-0]//Al2O3[101-0] or ZnO[101-0]//Al2O3[101-0], and were surrounded by highly defective domain boundaries with threading dislocations. The films grown at 800 oC with 1 mTorr O2 showed 2-dimensional layered growth with only one in-plane epitaxial relationship, ZnO[112-0]//Al2O3[101-0]. Most of the defects in the layered grown films were basal plane stacking faults near the interface between ZnO and the substrate. The formation mechanism of the 30o-twisted domains with the in-plane orientation of ZnO[101-0]//Al2O3[101-0] is discussed.Comment: 20 pages, 4 figure

QED radiative corrections to the decay pi^0 to e^+e^-

We reconsider QED radiative corrections (RC) to the $\pi^{0}\to e^{+}e^{-}$ decay width. One kind of RC investigated earlier has a renormalization group origin and can be associated with the final state interaction of electron and positron. It determines the distribution of lepton pair invariant masses in the whole kinematic region. The other type of RC has a double-logarithmic character and is related to almost on-mass-shell behavior of the lepton form factors. The total effect of RC for the $\pi^{0}\to e^{+}e^{-}$ decay is estimated to be 3.2% and for the decay $\eta \to e^{+}e^{-}$ is 4.3%.Comment: 12 pages, 3 figure