El número de pacientes necesarios a tratar para producir daño. Medicamentos que salen del mercado. Europa #patientsafety
The number needed to treat to be harmed: medicines withdrawn from the European market. #patientsafety
http://www.tandfonline.com/doi/abs/10.1080/14740338.2016.1217989
Objective:  To explore the usefulness of number needed to treat to be harmed  (NNTH), in benefit-risk assessments, by studying the agreement between  NNTH values and withdrawals of medicines from European market due to  safety reasons.
Methods:  Medicines with data from longitudinal studies were included. Studies  were identified from European Medicines Agency’s Reports. Meta-analyses  were performed to pool odds ratios (OR) with 95% confidence-intervals  (CI). Published control event rates were applied to ORs to calculate  NNTHs (95%CI) for selected adverse events.
Results:  NNTH (95%CI) decreased from pre- to post-marketing for the eight  medicines included: peripheral neuropathy (∞ vs. 12[non-significant; NS]  with almitrine; heart valve disease with benfluorex (∞ vs. NNTH ranging  from 7[4–13] to 7[5–9]); myopathy (−4096[NS] vs. 797[421–1690]),  new-onset diabetes (113[NS] vs. 390[425–778]), bleeding (∞ vs.  517[317–1153]), and infection (∞ vs. 253[164–463]) with  niacin-laropiprant; psychiatric disorders (12[7–34] vs. 9[5–24]) with  rimonabant; myocardial infarction (MI) [−1305 vs. 270[89–4362]) with  rofecoxib; MI (−510 vs. NNTH ranging from 152[55–4003] to 568[344–1350])  with rosiglitazone; cardiovascular events (∞ vs. 245[129–1318]) with  sibutramine; and liver injury (∞ vs. 5957[NS]) with ximelagatran.
Conclusion:  NNTH have potential of use as a supportive tool in benefit-risk  re-evaluations of medicines and may help regulators to making decisions  on drug safety.
-un saludo juan gérvas