Epidemiology and pattern of care of breakthrough cancer pain in a longitudinal sample of cancer patients: results from the Cancer Pain Outcome Research Study Group.
OBJECTIVE
Breakthrough cancer pain (BTcP) is a frequent event in cancer patients, with a prevalence from 19% to 95%. The reasons for such variability are explained by several factors, including different definitions across studies. In the framework of a wider initiative, we have analyzed the epidemiology of BTcP and identified factors associated with the pattern of care.


METHODS
This study reports the results from a multicenter, prospective, nonrandomized, longitudinal study carried out in Italy between 2006 and 2007 on patients with cancer and pain. Transient exacerbations of pain were assessed with 3 different questions, and 1 composite variable to operationally define BTcP was then used as main outcome. After univariate analysis, a logistic model was also fitted to identify prognostic and predictive factors.


RESULTS
One hundred and ten centers recruited 1801 cases of which 40.3% had BTcP at baseline. Most patients did not receive rescue therapy at the time of study inclusion. Univariate analysis identified several associations with clinical variables. A strong association has been also found with the type of recruiting centers, with oncologic wards reporting a somewhat lower proportion of patients with BTcP (-30%) when compared with palliative centers. Patients with BTcP had a high probability of dying (OR=1.4, 95% CI: 1.1-1.7, P-value 0.006) and to change of the opioid with another for analgesic failure or for side effects (OR=1.4, 95% CI: 1.0-1.9, P-value 0.040)


CONCLUSIONS
These findings confirm the high prevalence of BTcP and substantial undertreatment and identify a few factors associated with prevalence and prognosis.
Greco
Maria Teresa
MT
Center for the Evaluation and Research on Pain (CERP), Istituto di Ricerche Farmacologiche Mario Negri, University of Milano, Via La Masa 19, Milan, Italy.
Corli
Oscar
O
Montanari
Mauro
M
Deandrea
Silvia
S
Zagonel
Vittorina
V
Apolone
Giovanni
G
D000368:Aged; D005260:Female; D006801:Humans; D007558:Italy; D016015:Logistic Models; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D009369:Neoplasms / Q000150:complications*; D010146:Pain / Q000188:drug therapy* / Q000453:epidemiology* / Q000209:etiology; D010147:Pain Measurement; D011237:Predictive Value of Tests; D011379:Prognosis; D011446:Prospective Studies; D011795:Surveys and Questionnaires; D016896:Treatment Outcome