Altered Mental Status

Altered mental status (AMS) is a broad clinical term used to describe any change in a person’s level of consciousness, awareness, cognition, behaviour, or orientation. It is not a diagnosis itself but rather a symptom that may indicate an underlying medical, neurological, metabolic, or psychiatric condition requiring prompt assessment.

Patients with altered mental status may present with confusion, agitation, lethargy, reduced responsiveness, disorientation, memory impairment, or complete unconsciousness. The onset may be sudden or gradual, and the severity can range from mild cognitive changes to coma.

There are numerous potential causes of altered mental status, including:

• Neurological disorders such as stroke, traumatic brain injury, seizures, or intracranial haemorrhage.
• Metabolic abnormalities including hypoglycaemia, hyperglycaemia, electrolyte disturbances, renal failure, or hepatic encephalopathy.
• Infections such as sepsis, meningitis, encephalitis, or severe systemic illness.
• Respiratory or cardiovascular conditions leading to hypoxia or poor cerebral perfusion.
• Drug or alcohol intoxication, overdose, or withdrawal.
• Medication adverse effects and polypharmacy.
• Psychiatric disorders that may mimic or contribute to altered cognition.

The assessment of a patient with altered mental status begins with rapid evaluation of the airway, breathing, and circulation, followed by assessment of consciousness using recognised tools such as the ACVPU scale or the Glasgow Coma Scale (GCS). Vital signs, blood glucose measurement, neurological examination, and a focused clinical history are essential components of the initial assessment.

Further investigations are guided by the clinical presentation and may include blood tests, electrocardiography, imaging studies such as CT or MRI, toxicology screening, or lumbar puncture where appropriate. Prompt identification of reversible causes is critical, as many conditions associated with altered mental status are medical emergencies.

Clinical decision tools and risk scores may assist healthcare professionals in assessing patients with altered mental status, but they should always be interpreted alongside a comprehensive clinical examination and professional judgement.

Early recognition and systematic evaluation of altered mental status can significantly improve patient outcomes by enabling timely diagnosis, appropriate treatment, and rapid escalation of care when necessary.