Automated pupillometry may help predict dosing of opioid agonist therapy for opioid use disorder

Boston, MA: In a new study, Crandall E. Peeler and colleagues found that automated pupillometry exhibited a minor but significant change in mean pupil size within 15 minutes after opioid agonist therapy (OAT) dosage and was linked with low withdrawal ratings. The findings of this study were published in the Journal of Addiction Medicine.

The severity of opioid withdrawal is graded using a crude visual assessment of pupil size. Little research has been conducted to investigate the clinical value of more precise automated pupillometry measures. Keeping this in mind, the following research was conducted to see if there is a statistically significant change in pupil size and reactivity, assessed to the hundredth millimeter using automated pupillometry, related with acceptable withdrawal symptom management in a diverse convenience sample of patients on methadone or buprenorphine for OUD. The secondary goal was to see how rapidly this change might be identified after OAT treatment.

During an acute hospitalization, 27 patients were included in this prospective cohort research to receive OAT to treat cravings or withdrawal. Six sets of automated pupillometry measurements were taken at regular intervals before and after OAT delivery. Pre and after OAT Clinical Opiate Withdrawal Scale readings were taken. The primary objectives included pupil size in both dim and bright lighting (mm). Secondary results were pupillary light response latency (s), constriction and dilation velocity (mm/s), and percent constriction (percent).

As a result, in both dim and strong light, the mean predosing pupil size was 4.33 1.40 mm and 2.96 0.79 mm, respectively. At 15 minutes post-dosingidentify, a substantially reduced mean pupil size was identified (4.01 1.34 mm, P = 0.0115 for dim lighting; 2.71 0.72 mm, P = 0.0003 for bright illumination), and this reduction in pupil size remained at further post dosing timepoints. Those who had a Clinical Opiate Withdrawal Scale 5 following dose saw a larger decrease in black pupil size. The remaining pupil reactivity metrics did not alter much.

In conclusion, it has been reported that using automated pupillometry, a minor but substantial shift in pupil size is identified immediately after OAT dose, which is linked with effective management of withdrawal symptoms. With further research, it is hoped that this objective measure can assist to teach or empower more healthcare practitioners to manage opioid withdrawal and improve outcomes for individuals with OUD.

Reference:

Peeler, C. E., Gorgy, M., Sadlak, N., Sathe, S., Tamashunas, N., Fiorello, M. G., Cabral, H., Paasche-Orlow, M. K., & Weinstein, Z. M. (2020). A Pilot Study of Automated Pupillometry in the Treatment of Opioid Use Disorder. In Journal of Addiction Medicine (Vol. 15, Issue 6, pp. 477–483). Ovid Technologies (Wolters Kluwer Health). https://doi.org/10.1097/adm.0000000000000794