Impact of comorbidity on survival of invasive bladder cancer patients, 1996-2007: a Danish population-based cohort study.
OBJECTIVE
To examine (i) the prevalence of comorbidity among invasive bladder cancer (IBC) patients, and (ii) the effect of comorbidity on IBC survival and mortality in Northern Denmark. Comorbidity has shown to be associated with treatment selection and survival in patients who undergo radical cystectomy for IBC.


METHODS
Patients with a diagnosis of IBC from Danish hospitals between 1996 and 2007 within a population of 1.6 million were identified through the Danish National Patient Registry. From hospital diagnosis data, we computed Charlson Comorbidity Index scores (0, 1-2, 3+) for IBC patients and computed absolute survival and relative mortality estimates according to comorbidity level.


RESULTS
We identified 3997 patients with IBC among whom 1715 (43%) had comorbidities. The prevalence of comorbidity tended to increase during the study period with those having scores 3+ increasing from 8%-12%. Three- and 5-year mortality rates were higher for patients with comorbidity, with mortality rates more than 2-fold higher among those with scores of 3+ and 1.5-fold higher among those with scores of 1-2 compared with no comorbidity. Generally, the same pattern was seen for 1-year relative survival rates.


CONCLUSIONS
Comorbidity was seen among 43% of IBC patients and severe comorbidity was a predictor of poorer survival.
Lund
Lars
L
Department of Urology, Viborg Hospital 8800, Viborg, Denmark. Dr.LL@Dadlnet.dk
Jacobsen
Jacob
J
Clark
Peter
P
Borre
Michael
M
Nørgaard
Mette
M
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015331:Cohort Studies; D003718:Denmark; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009361:Neoplasm Invasiveness; D015995:Prevalence; D015996:Survival Rate; D013997:Time Factors; D001749:Urinary Bladder Neoplasms / Q000150:complications* / Q000401:mortality* / Q000473:pathology