Objectives: Few studies have evaluated the impact of risk factors and comorbidity on overall survival (OS) in patients with pancreatic ductal adenocarcinoma (PDAC). The aim was to investigate the prognostic importance of Charlson's age-comorbidity index (CACI) and other risk factors on prognosis in a clinical real-world cohort of PDAC patients. Methods: A total of 1,159 patients with PDAC who had received at least one cycle of adjuvant or palliative chemotherapy were included from the Danish BIOPAC study. We analysed OS according to CACI, tobacco smoking, alcohol intake, performance status (PS), BMI and diabetes. Hazard ratios (HRs) and 95% confidence intervals (CIs) were estimated for OS using Cox proportional hazards regression. Results: At the end of follow-up, 994 (86%) patients had died. The median OS was 298 days for all patients (range 3–3010) and shortest in patients with stage IV. No association with short OS was seen for CACI > 2, diabetes, alcohol abuse, tobacco smoking, hypertension, and high BMI. Multivariate analysis showed that stage (IV vs. I: HR = 9.05, 95% CI 5.17–15.84), PS (2 vs. 0: HR = 3.67, 2.92–4.61) and treatment with angiotensin-converting enzyme inhibitors (yes vs. no: HR = 1.31, 1.06–1.61) were independent negative prognostic factors. Conclusions: We found that CACI, diabetes, tobacco smoking, alcohol abuse, hypertension, and high BMI were not associated with OS in a real-world cohort of patients with PDAC treated with chemotherapy. Only stage and PS were prognostic parameters.