Trends in adverse drug reactions related to oral weak opioid analgesics in therapeutic use in adults: A 10-year French vigilances retrospective study

Endogenous opiates and behavior: 2023

This paper is the forty-sixth consecutive installment of the annual anthological review of research concerning the endogenous opioid system, summarizing articles published during 2023 that studied the behavioral effects of molecular, pharmacological and genetic manipulation of opioid peptides and receptors as well as effects of opioid/opiate agonists and antagonists. The review is subdivided into the following specific topics: molecular-biochemical effects and neurochemical localization studies of endogenous opioids and their receptors (1), the roles of these opioid peptides and receptors in pain and analgesia in animals (2) and humans (3), opioid-sensitive and opioid-insensitive effects of nonopioid analgesics (4), opioid peptide and receptor involvement in tolerance and dependence (5), stress and social status (6), learning and memory (7), eating and drinking (8), drug and alcohol abuse (9), sexual activity and hormones, pregnancy, development and endocrinology (10), mental illness and mood (11), seizures and neurologic disorders (12), electrical-related activity and neurophysiology (13), general activity and locomotion (14), gastrointestinal, renal and hepatic functions (15), cardiovascular responses (16), respiration and thermoregulation (17), and immunological responses (18).

Probing polypharmacy, ageing and sex effects on physical function using different tests

BACKGROUND

Ageing, sex and polypharmacy affect physical function.

OBJECTIVES

This mouse study investigates how ageing, sex and polypharmacy interact and affect grip strength, balance beam and wire hang, correlating and comparing the different test results between and within subgroups.

METHODS

Young (2.5 months) and old (21.5 months) C57BL/6 J male and female mice (n = 10-6/group) were assessed for physical function at baseline on grip strength, balance beam and wire hang with three trials of 60 s (WH60s) and one trial of 300 s (WH300s). Mice were randomised to control or diet containing a high Drug Burden Index (DBI, total anticholinergic and sedative drug exposure) polypharmacy regimen (metoprolol, simvastatin, citalopram, oxycodone and oxybutynin at therapeutic oral doses). Following 6-8 weeks of treatment, mice were reassessed.

RESULTS

High DBI polypharmacy and control mice both showed age group differences on all tests (p < 0.05). Only control mice showed sex differences, with females outperforming males on the WH60s and balance beam for old mice, WH300s for young mice (p < 0.05). Polypharmacy reduced grip strength in all subgroups (p < 0.05) and only in old females reduced wire hang time and cumulative behaviour and balance beam time and %walked (p < 0.05). Physical function assessments were all correlated with each other, with differences between subgroups (p < 0.05), and mice within subgroups showed interindividual variability in performance.

CONCLUSION

Age, sex and polypharmacy have variable effects on different tests, and behavioural measures are useful adjuvants to assessing performance. There was considerable within-group variability in change in measures over time. These findings can inform design and sample size of future studies.