We defined the prevalence and impact on survival of clinical bedside variables in 385 patients with symptomatic congestive heart failure (CHF), of whom there were 176 with and 209 without diabetes mellitus. Patients were consecutively hospitalized and admitted for various acute conditions. Following discharge all-cause mortality was recorded. Prevalence and association of various variables with mortality were statistically analyzed. Prevailing in the diabetics versus nondiabetics were younger age (p < 0.05), pulmonary edema on admission (p = 0.002), using furosemide >80 mg/day (p < 0.01) for >1 year (p < 0.01) and hyponatremia (p = 0.01). Less prevalent were chronic lung disease (p < 0.01) and cardiac arrhythmias (p = 0.001). On follow-up extending up to 60 months, diabetic patients, especially those with fasting blood glucose levels on admission ≧180 mg/dl, survived for a shorter period of time than nondiabetics (p = 0.02). Associated with increased mortality in the diabetic group were female gender (p = 0.04), furosemide ≧80 mg/day (p < 0.001) and renal dysfunction (RD; p = 0.04). The respective variables in the nondiabetics were advanced age (p < 0.001) and RD (p = 0.002). Although they were younger, diabetic patients presented more severe CHF. It is recommended that special attention should be given to diabetic females, those using higher furosemide dosages and those suffering from RD.