Prevalence and Risk Factors Associated with Use of QT-Prolonging Drugs in Hospitalized Older People.

AIMS: The objective of this study was to evaluate the prevalence of the prescription of QT-prolonging drugs at hospital admission and discharge and the risk factors associated with their use in older people (aged 65 years and older). METHODS: Data were obtained from the REPOSI (REgistro POliterapie SIMI [Società Italiana di Medicina Interna]) registry, which enrolled 4035 patients in 2008 (n = 1332), 2010 (n = 1380), and 2012 (n = 1323). Multivariable logistic regression was performed to determine the risk factors independently associated with QT-prolonging drug use. QT-prolonging drugs were classified by the risk of Torsades de Pointes (TdP) (definite, possible, or conditional) according to the Arizona Center for Education and Research on Therapeutics (AzCERT) classification. Specific drug combinations were also assessed. RESULTS: Among 3906 patients prescribed at least one drug at admission, 2156 (55.2%) were taking at least one QT-prolonging drug. Risk factors independently associated with the use of any QT-prolonging drugs were increasing age (odds ratio [OR] 1.02, 95% CI 1.01-1.03), multimorbidity (OR 2.69, 95% CI 2.33-3.10), hypokalemia (OR 2.79, 95% CI 1.32-5.89), atrial fibrillation (OR 1.66, 95% CI 1.40-1.98), and heart failure (OR 3.17, 95% CI 2.49-4.05). Furosemide, alone or in combination, was the most prescribed drug. Amiodarone was the most prescribed drug with a definite risk of TdP. Both the absolute number of QT-prolonging drugs (2890 vs. 3549) and the number of patients treated with them (2456 vs. 2156) increased at discharge. Among 1808 patients not prescribed QT-prolonging drugs at admission, 35.8% were prescribed them at discharge. CONCLUSIONS: Despite their risk, QT-prolonging drugs are widely prescribed to hospitalized older persons. The curriculum for both practicing physicians and medical students should be strengthened to provide more education on the appropriate use of drugs in order to improve the management of hospitalized older people.

The influence of age on the recovery of the ERG photostress test.

INTRODUCTION: Focal ERG associated with photostress test could be a useful diagnostic method for evaluating macular visual function. The main aim of this study was to evaluate the effect of age on the recovery time constant of the ERG photostress test. The second aim was to assess the sources of variability which affect the measurements. METHODS: Fifty-four healthy subjects (108 eyes), aged between 21 and 77, with corrected VA of 20/20 or more and absence of any ocular or systemic disease, were recruited. For each eye ERG response to focal (20° in diameter) 42-Hz stimulation was recorded: three series of 200 summations in base conditions and a six series of 42-Hz ERGs (100 summations each) at 10, 40, 80, 180, 300 and 420 s after bleaching by a white spot of light (20° in diameter) from a direct ophthalmoscope (800 cd/m²) pointed at macular region for 30 s. Fourier analysis was performed and amplitude of the first harmonica calculated. The relationship of basal amplitudes with subject age and gender, and the kinetics of macular function recovery were assessed through mixed-effects models. RESULTS: Mean basal amplitude decreases by 0.046 µV for year of life. The recovery after bleaching is proportional to age with an increase of 4.31 s for decade. Restoration of amplitude is slower in older subjects. DISCUSSION: There is a significant decrease in macular ERG amplitude with age. The macular recovery after photostress shows exponential kinetics that are less efficient in older subjects: this could be related to lower effectiveness of photopigment restoration in advanced age.