Causes of Increased Mortality in Schizophrenia The mortality rate is elevated in patients with schizophrenia. The following are the common natural and unnatural causes of increased mortality in patients with schizophrenia. Unnatural Causes Approximately 60% of the increased mortality is because of unnatural causes, especially suicide and accidents. Natural Causes Nearly 40% of the increased risk is because of natural causes, such as: Cardiovascular disease Smoking Sedentary lifestyle Obesity Medication side effects