INS and diabetes mellitus: Regarding past medical history, hypertension was defined as patients requiring anti-hypertensive therapy to maintain blood pressure under 140/90 mmHg; diabetes mellitus (DM) was defined as patients requiring oral antidiabetic drugs/insulin therapy and diagnosed prior to admission; asthma was defined as a reversible obstructive airway disease based on lung function tests prior to admission; heart failure (HF) was defined as patients suffering from cardiomyopathy and presenting with dyspnea and lower limb edema.