Benzodiazepines and hip fracture

Case-control studies

Abstract

Introduction: benzodiazepines (BZD) are widely used drugs in the clinical practice. They are effective in the symptomatic treatment of anxiety, short-term insomnia, epileptic seizures, alcohol withdrawal effect and anesthetic induction. In the elderly, they may cause adverse effect such as lack of motor coordination and muscle weakness which can lead to falling, increasing the risk of hip fracture.
Objective: to determine whether the consumption of benzodiazepine may be associated with hip fracture.
Method: a case-control study was designed (1:2) and conducted (three months in 2013 and three months in 2014) . A “case” was defined for patients with a traumatic hip injury. “Control” was defined for patients of same sex and age (± 5 años) who had been admitted in the same week for a different cause (medical or surgical). Demographic data was collected, as well as the consumption of drugs potentially involved in hip fracture. The study considered patients had consumed benzodiazepine when it had been received within five days prior to the fracture. Odd ratios were calculated and confidence intervals were 95%.
Results: 29 cases and 60 controls were obtained. Average age (standard deviation) in the cases group was 82,8 (6.4) years old and 82.1 (5.2) years old in the control group (p > 0.05). Female: 25 (86%) in the cases group and 49 (82%) in the control group (p > 0.05). BZD were consumed by 16/29 (61.5%) cases and 13/60 (21.7%) controls (p < 0.05). All patients who had consumed BZD in both groups had done so for over six weeks. The odd ratio for hip fracture in patients who consumed BZD was 4.5 (confidence interval 95% - 1.7-11.6).
Conclusions: the study points out that BZD increases the risk of hip fracture, and that patients consume it for non-advisable periods of time. National policies should be devised to encourage a rational use of these drugs.