The impact of opioid-induced constipation among chronic pain patients with sufficient laxative use

Background The impact of sufficient laxative use on opioid-induced constipation (OIC) is not known. Aim To understand the experience and symptom burden over time among chronic non-cancer pain patients with OIC who are sufficient laxative users. Methods A prospective longitudinal study was conducted in United States, Canada, Germany and UK which included medical record abstraction, patient surveys and physician surveys. Patients on daily opioid therapy for ≥ 4 weeks for chronic non-cancer pain with OIC were recruited from physician offices and completed the survey at Baseline and Weeks 2, 4, 6, 8, 12, 16, 20 and 24. Sufficient laxative use was defined as at least one laxative remedy 4 or more times in the prior 2 weeks. Results Of the 489 patients who completed the Baseline survey and met OIC criteria, 234 (48%) were categorised as sufficient laxative users; 65% were female; 90% were white and 75 (32%) maintained sufficient laxative use for > 7 of the 8 follow-up periods. Patient Assessment of Constipation-Symptom (PAC-SYM) and Patient Assessment of Constipation-Quality of Life (PAC-QOL) scores indicated moderate symptom severity and impact. PAC-SYM and PAC-QOL scores remained relatively unchanged over time with a maximum score change of 0.5 points. Work productivity and activity impairment remained relatively constant. Mean per cent activity impairment because of constipation was 37% at Baseline and 34% at Week 24. Conclusions These findings demonstrate constipation persists despite sufficient laxative use with little improvement in symptoms, HRQL or activity impairment. This ongoing burden emphasises the need to identify more efficacious constipation therapies for this chronic pain patient population.