CNS Drugs

, Volume 27, Issue 2, pp 155–161

Newly Initiated Opioid Treatment and the Risk of Fall-Related Injuries

A Nationwide, Register-Based, Case-Crossover Study in Sweden

Authors

    • Division of Global Health/IHCAR, Department of Public Health Sciences, Karolinska Institutet
    • Department of Clinical Pharmacology C1:68Karolinska University Hospital Huddinge
  • Lucie Laflamme
    • Division of Global Health/IHCAR, Department of Public Health Sciences, Karolinska Institutet
  • Jette Möller
    • Division of Public Health Epidemiology, Department of Public Health Sciences, Karolinska Institutet
Original Research Article

DOI: 10.1007/s40263-013-0038-1

Cite this article as:
Söderberg, K.C., Laflamme, L. & Möller, J. CNS Drugs (2013) 27: 155. doi:10.1007/s40263-013-0038-1

Abstract

Background

There is growing epidemiological evidence that opioids may increase the risk of unintentional injuries and it is plausible that the time of initiation is most critical in that respect. Studies on fall-related injuries remain few, limited and mostly focused on specific groups of elderly patients.

Objective

The objective of this study was to assess the short-term effects of newly prescribed opioids on the risk of fall-related injuries in the general adult population.

Methods

A case-crossover design was applied on national register data linking, at the individual level, fall-injury information involving adults aged 18 years and above identified in the Swedish National Inpatient Register (during the period 1 May 2006 to 31 December 2009) and dispensed drugs from the Swedish Prescribed Drug Register (n = 167,257 cases with a first fall-related injury). All types of opioid substances were considered, classified according to the Anatomical Therapeutic Chemical (ATC) classification system. We investigated newly dispensed opioids 28 days preceding the injury, compared with an earlier, and equally long, control period following a 3-month washout period. Conditional logistic regression was used to estimate odds ratio (OR) and 95 % confidence interval (CI). The analyses were also conducted stratified by age group, by type of fall and for each period of 1 week during the 28-day period.

Results

From among the fall-injured patients, 7,450 patients (4.5 %) had a new opioid dispensation within 28 days prior to the injury, of which the most frequent types were tramadol (2.0 %) and codeine (1.1 %). Consistently increased risks of fall-related injuries associated with a new prescription of any opioid were found and they were most pronounced among young adults, 18–29 years of age (OR, 7.17; 95 % CI 5.04–10.2). The closer the dispensation date to the injury, the higher the odds: an OR of 5.14 (95 % CI 4.76–5.55) during the first week of opioid treatment and 1.23 (95 % CI 1.10–1.38) for the fourth week. Of the documented falls, the risk was most pronounced for falls from ‘another, high level’ (OR, 5.33; 95 % CI 3.99–7.10).

Conclusions

Newly prescribed opioids may trigger injurious falls. The effect lowers over time and is less pronounced with increasing age. The risk is also higher for fall from height.

Copyright information

© Springer International Publishing Switzerland 2013