Risk of atrial fibrillation among bisphosphonate users: a multicenter, population-based, Italian study

Summary: Bisphosphonate treatment is used to prevent bone fractures. A controversial association of bisphosphonate use and risk of atrial fibrillation has been reported. In our study, current alendronate users were associated with a higher risk of atrial fibrillation as compared with those who had stopped bisphosphonate (BP) therapy for more than 1 year.Introduction: Bisphosphonates are widely used to prevent bone fractures. Controversial findings regarding the association between bisphosphonate use and the risk of atrial fibrillation (AF) have been reported. The aim of this study was to evaluate the risk of AF in association with BP exposure.Methods: We performed a nested case-control study using the databases of drug-dispensing and hospital discharge diagnoses from five Italian regions. The data cover a period ranging from July 1, 2003 to December 31, 2006. The study population comprised new users of bisphosphonates aged 55 years and older. Patients were followed from the first BP prescription until an occurrence of an AF diagnosis (index date, i.e., ID), cancer, death, or the end of the study period, whichever came first. For the risk estimation, any AF case was matched by age and sex to up to 10 controls from the same source population. A conditional logistic regression was performed to obtain the odds ratio with 95 % confidence intervals (CI). The BP exposure was classified into current (<90 days prior to ID), recent (91–180), past (181–364), and distant past (≥365) use, with the latter category being used as a reference point. A subgroup analysis by individual BP was then carried out.Results: In comparison with distant past users of BP, current users of BP showed an almost twofold increased risk of AF: odds ratio (OR) = 1.78 and 95 % CI = 1.46–2.16. Specifically, alendronate users were mostly associated with AF as compared with distant past use of BP (OR, 1.97; 95 % CI, 1.59–2.43).Conclusion: In our nested case-control study, current users of BP are associated with a higher risk of atrial fibrillation as compared with those who had stopped BP treatment for more than 1 year

Liver injury due to amoxicillin vs. amoxicillin/clavulanate: a subgroupnalysis of a drug-induced liver injury case-control study in Italy

Several studies showed that amoxicillin plus clavulanic acid (co-amoxiclav) is one of the most common agents associated to serious Drug Induced Liver Injury (DILI). We estimated the risk of acute serious DILI associated with amoxicillin alone compared with co-amoxiclav, through a multicenter case-control study carried out in nine Italian hospitals from October 2010 to January 2014.Cases were adults, with a diagnosis of acute liver injury. Controls presented acute clinical disorders, not related to chronic conditions and not involving the liver. Adjusted Odds Ratio (ORs) with 95% CI were calculated initially with a bivariate and then multivariate analysis. We analysed 179 cases matched to 1770 controls. Seven cases were exposed to amoxicillin (adjusted OR 1.69, 95% CI 0.72-3.98) and 22 cases to co-amoxiclav (adjusted OR 3.00, 95% CI 1.76-5.40). Co-amoxiclav almost doubled the risk of serious acute liver injury compared to amoxicillin alone. The incidence of co-amoxiclav induced DILI is very low but the widespread use of this drug by the general population makes the risk clinically relevant. The often inappropriate prescription of antimicrobial agents, and in particular of co-amoxiclav, could expose a given patient to a life-threatening risk compared to a negligible clinical benefit

On Nontrival Equilibria in Finitely Repeated Games

Background: Data on the effect of oral bisphosphonates (BPs) on risk of upper gastrointestinal complications (UGIC) are conflicting. We conducted a large population-based study from a network of Italian healthcare utilization databases aimed to assess the UGIC risk associated with use of BPs in the setting of secondary prevention of osteoporotic fractures.Methods: A nested case-control study was carried out within a cohort of 68,970 patients aged 45 years or older, who have been hospitalized for osteoporotic fracture from 2003 until 2005. Cases were the 804 patients who experienced hospitalization for UGIC until 2007. Up to 20 controls were randomly selected for each case. Conditional logistic regression model was used to estimate odds ratio (OR) associated with current and past use of BPs (i.e. for drug dispensation within 30 days and over 31 days prior the outcome onset, respectively) after adjusting for several covariates.Results: Compared with patients who did not use BPs, current and past users had OR (and 95% confidence interval) of 0.86 (0.60 to 1.22) and 1.07 (0.80 to 1.44) respectively. There was no difference in the ORs estimated according with BPs type (alendronate or risedronate) and regimen (daily or weekly), nor with co-therapies and comorbidities.Conclusions: Further evidence that BPs dispensed for secondary prevention of osteoporotic fractures are not associated with increased risk of severe gastrointestinal complications is supplied from this study. Further research is required to clarify the role BPs and other drugs of co-medication in inducing UGI