Comorbidity and ovarian cancer survival in Denmark, 1995-2005: a population-based cohort study.

The impact of comorbid diseases on ovarian cancer survival is largely unknown. We therefore examined (i) the prevalence of comorbidity among ovarian cancer patients and (ii) the impact of comorbidity on ovarian cancer survival and mortality. Using hospital discharge data, we identified Danish women diagnosed with ovarian cancer between 1995 and 2005 (n= 1995 within a population of 1.6 million) and then computed Charlson comorbidity index scores (0, 1-2, and 3+). We estimated the prevalence of comorbidity and computed absolute survival and relative mortality rate ratios (MRRs) according to comorbidity level, using patients with Charlson score 0 as the reference group. During the study period, the proportion of patients without comorbidity fell from 81% to 75%, while the proportion of patients with comorbidity score 1-2 and 3+ rose from 16% to 21% and from 4% to 5%, respectively. Overall 1-year survival increased from 68% in 1995-1997 to 70% in 1998-2000 and to 73% in 2001-2004. For patients with Charlson score 1-2, 1-year adjusted MRRs were 1.1 (95% CI, 0.8-1.6) in 1995-1997, 1.3 (95% CI, 1.0-1.8) in 1998-2000, and 1.7 (95% CI, 1.3-2.4) in 2001-2004. For patients with Charlson score 3+, 1-year adjusted MRRs were 2.4 (95% CI, 1.4-4.3) in 1995-1997, 1.6 (95% CI, 1.0-2.7) in 1998-2000, and 2.2 (95% CI, 1.3-3.8) in 2001-2004. The 5-year MRRs were similar to the 1-year MRRs. One quarter of Danish women with ovarian cancer were found to have comorbid conditions, and 5% had severe comorbidity. Severe comorbidity was a predictor of poorer survival.

Improved survival of patients with ovarian cancer in Northern Denmark, 1985-2004.

OBJECTIVE: Ovarian cancer is a serious disease with a high mortality. Our aim was to examine changes in the survival of patients with ovarian cancer in Northern Denmark. STUDY DESIGN AND SETTING: Patients (no. = 3,719) with an incident discharge diagnosis of ovarian cancer (1985-2004) from any hospital in four Danish counties (population, 1.6 million) were included and tracked for mortality through the Danish Civil Registration System. We determined survival and mortality rates stratified by age, and used Cox proportional hazard regression analyses to assess changes over time. RESULTS: Overall survival rate improved between 1985 and 2004. One-year survival increased from 61% to 73%, and five-year survival from 30% to 38%. Compared with the period 1985-1989 the age-adjusted one-year mortality rate ratio (MRR) was 0.65 (2000-2004) and the age-adjusted five-year MRR was 0.80 (1995-1999). The improvement was most pronounced in patients older than 40 years. CONCLUSION: The survival of ovarian cancer patients has improved in Denmark in recent decades. This change may be the result of improved treatment.

Accuracy of ovarian cancer ICD-10 diagnosis in a Danish population-based hospital discharge registry.

OBJECTIVE: We estimated the accuracy of ICD-10 diagnosis of ovarian cancer in a Danish discharge registry (HDR) by comparing it with Cancer Registry data (DCR). STUDY DESIGN AND SETTING: Patients (N=489) living in North Jutland County, Denmark with ovarian cancer or borderline tumour registered in the HDR or the DCR. We estimated the completeness and positive predictive value (PPV) of ovarian cancer discharge diagnosis. Mortality rates were constructed for both registries. RESULTS: The completeness in the HDR for ovarian cancer was 96% (95% confidence interval [CI]: 94%-98%) and PPV was 87% (95% CI: 85%-90%). 87 (18%) of the patients coded with ovarian cancer in the HDR had borderline tumours. When borderline tumours were excluded from the DCR, the PPV declined to 69% and the completeness did not change. The mortality rate ratio for ovarian cancer registered in the HDR compared to the DCR was 1.08 (95% CI: 0.90-1.29). CONCLUSION: The discharge data (ICD-10) had some misclassification, but can be a valuable tool in assessment of the prognosis of ovarian cancer.