Opioid Treatment Associated With Cognitive Dysfunction
Possible or definite cognitive dysfunction seen in one-third of opioid-treated cancer patients
TUESDAY, March 1 (HealthDay News) -- One-third of opioid-treated patients with cancer have possible or definite cognitive dysfunction, according to a study published online Feb. 28 in the Journal of Clinical Oncology.
Geana P. Kurita, Ph.D., from the University of Southern Denmark in Copenhagen, and colleagues examined the prevalence and associated factors of cognitive dysfunction in cancer patients treated with opioids. The study included 1,915 adult participants of the European Pharmacogenetic Opioid Study who had cancer with moderate or severe pain and were treated with opioids for at least three days. Using Mini-Mental State Examination (MMSE) scores, cognitive function was characterized as definite cognitive dysfunction (scores < 24), possible cognitive dysfunction (scores 24 to 26), and no cognitive dysfunction (scores > 26). Factors affecting cognitive dysfunction were also assessed.
The investigators found that 32.9 percent of patients had MMSE scores lower than 27. Compared to other cancers, patients with lung cancer had an increased likelihood of lower MMSE scores (odds ratio [OR], 1.46). Compared to patients receiving daily opioid doses of less than 80 mg, those receiving 400 mg or more of oral morphine equivalents every day had an increased likelihood of having lower MMSE scores (OR, 1.75). Older age, time since diagnosis (less than 15 months), low Karnofsky performance status, and absence of breakthrough pain were associated with cognitive dysfunction.
"We found in a large sample of opioid-treated patients with cancer that one-third of patients had possible or definite cognitive dysfunction (MMSE scores < 27)," the authors write.
One author disclosed financial relationships with Mundipharma, Nycomed, and Pfizer. Another author disclosed an honorary relationship with Mundipharma.