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The number needed to treat to be harmed: medicines withdrawn from the European market.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.