What is the most common cause of death in survivors of spinal cord injuries?

Rationale: A. Cancer can occur in individuals with spinal cord injuries, particularly due to long-term factors such as chronic inflammation, smoking, or reduced screening access. However, it is not the leading cause of death in this population. Although life expectancy has improved, cancer-related deaths are still less frequent compared to respiratory complications. B. Pneumonia is the most common cause of death in survivors of spinal cord injuries. This is primarily due to impaired respiratory function. Injury to the spinal cord, especially at higher levels (such as cervical injuries), can weaken or paralyze the diaphragm and intercostal muscles, leading to shallow breathing and poor lung expansion. In addition, the cough reflex is often ineffective, preventing proper clearance of secretions. This leads to mucus accumulation, creating an environment for bacterial growth and infection. Immobility and prolonged bed rest further increase the risk of atelectasis and infection. Over time, repeated respiratory infections significantly increase mortality risk, making pneumonia the leading cause of death in this population. C. Individuals with spinal cord injuries have a higher risk of depression, social isolation, and psychological distress, which can increase the risk of suicide. However, despite this elevated risk, suicide is not the most common cause of death when compared to medical complications such as respiratory infections. D. Pulmonary embolism is a significant risk, particularly in the acute phase after injury due to immobility, venous stasis, and hypercoagulability. Preventive measures such as anticoagulation and compression devices have reduced its incidence. While it remains a serious complication, it is not the leading long-term cause of death compared to pneumonia.