Long-term opioid use in seniors following hip and knee arthroplasty in Ontario: a historical cohort study

PURPOSE

Canadian seniors who undergo hip and knee arthroplasty often experience significant postoperative pain, which could result in persistent opioid use. We aimed to document the impact of preoperative opioid use and other characteristics on postoperative opioid prescriptions in elderly patients following hip and knee replacement before widespread dissemination of opioid reduction strategies.

METHODS

We conducted a historical cohort study to evaluate postoperative opioid use in patients over 65 yr undergoing primary total hip and knee replacement over a ten-year period from 1 April 2006 to 31 March 2016, using linked de-identified Ontario administrative data. We determined the use of preoperative opioids and the duration of postoperative opioid prescriptions (short-term [1-90 days], prolonged [91-180 days], chronic [181-365 days], or undocumented).

RESULTS

The study included 49,638 hip and 85,558 knee replacement patients. Eighteen percent of hip and 21% of knee replacement patients received an opioid prescription within 90 days before surgery. Postoperatively, 51% of patients filled opioid prescriptions for 1-90 days, while 24% of hip and 29% of knee replacement patients filled prescriptions between 6 and 12 months, with no impact of preoperative opioid use. Residence in long-term care was a significant predictor of chronic opioid use (hip: odds ratio [OR], 2.64; 95% confidence interval [CI], 1.93 to 3.59; knee: OR, 2.46; 95% CI, 1.75 to 3.45); other risk factors included female sex and increased comorbidities.

CONCLUSION

Despite a main goal of joint arthroplasty being relief of pain, seniors commonly remained on postoperative opioids, even if not receiving opioids before surgery. Opioid reduction strategies need to be implemented at the surgical, primary physician, long-term care, and patient levels. These findings form a basis for future investigations following implementation of opioid reduction approaches.

Stereological and histopathological evaluation of doxorubicin-induced toxicity in female rats' ovary and uterus and palliative effects of quercetin and vitamin E

Doxorubicin (DOX) is a widely used chemotherapeutic agent with demonstrated reproductive toxicity. This study sought to determine the DOX-induced toxicity in the ovary and uterus and the preventive effects of quercetin (QCT) and vitamin E (Vit.E). Female rats were divided into six groups as follows: control, QCT (20 mg/kg), Vit.E (200 mg/kg), DOX (accumulative 15 mg/kg), DOX/QCT, and DOX/Vit.E. After 3 weeks, the toxicity of DOX in ovarian and uterine tissues and the potential palliative effects of QCT and Vit.E were evaluated by histopathological-stereological methods. The findings indicate a dramatic decline in the number of ovarian follicles (p < 0.001), ovarian and its associated structures volume, the volume of the uterus, its layers, and related structures (p < 0.05). Coadministration of QCT and Vit.E with DOX-treated rats demonstrated an alleviative effect on most of the studied parameters. Nevertheless, few adverse effects were recognized concerning these antioxidants administration (p < 0.05). In conclusion, the findings of this study support the protective role of these dietary supplements in the prevention of DOX-induced toxicity in uterine and ovarian tissues.

The experimental and theoretical QM/MM study of interaction of chloridazon herbicide with ds-DNA

We report a multispectroscopic, voltammetric and theoretical hybrid of QM/MM study of the interaction between double-stranded DNA containing both adenine-thymine and guanine-cytosine alternating sequences and chloridazon (CHL) herbicide. The electrochemical behavior of CHL was studied by cyclic voltammetry on HMDE, and the interaction of ds-DNA with CHL was investigated by both cathodic differential pulse voltammetry (CDPV) at a hanging mercury drop electrode (HMDE) and anodic differential pulse voltammetry (ADPV) at a glassy carbon electrode (GCE). The constant bonding of CHL-DNA complex that was obtained by UV/vis, CDPV and ADPV was 2.1×10(4), 5.1×10(4) and 2.6×10(4), respectively. The competition fluorescence studies revealed that the CHL quenches the fluorescence of DNA-ethidium bromide complex significantly and the apparent Stern-Volmer quenching constant has been estimated to be 1.71×10(4). Thermal denaturation study of DNA with CHL revealed the ΔTm of 8.0±0.2°C. Thermodynamic parameters, i.e., enthalpy (ΔH), entropy (ΔS°), and Gibbs free energy (ΔG) were 98.45 kJ mol(-1), 406.3 J mol(-1) and -22.627 kJ mol(-1), respectively. The ONIOM, based on the hybridization of QM/MM (DFT, 6.31++G(d,p)/UFF) methodology, was also performed using Gaussian 2003 package. The results revealed that the interaction is base sequence dependent, and the CHL has more interaction with ds-DNA via the GC base sequence. The results revealed that CHL may have an interaction with ds-DNA via the intercalation mode.