Patient selection: patient receiving opioids for cancer-related pain
Prevalence of cognitive dysfunction: about one third of study population (possible or definite)
Modifiable risk factors for cognitive dysfunction:
(1) daily dose of opioids >= 400 mg oral morphine or equivalent
(2) absence of breakthrough pain
Nonmodifiable risk factors for cognitive dysfunction:
(1) lung cancer
(2) recent diagnosis of cancer (< 15 months)
(3) low Karnofsky Performance Status (KPS) = unable to care for self (10 to 40)
(4) older age (>= 70 years of age)
Factors associated with a reduced risk for cognitive impairment:
(1) age < 60 years
(2) able to carry out normal activities = KPS 80 to 100
where:
• The absence of breakthrough pain suggests that the dose of opioids may be higher than necessary.
