Environmental Exposure: This is the most likely cause of hypothermia in the elderly, as they may be more susceptible to cold temperatures due to decreased mobility, social isolation, or inadequate heating in their homes.

Hypothyroidism: Hypothyroidism can cause decreased metabolism, leading to hypothermia, and is more common in the elderly population.
Diabetes: Diabetes, particularly if uncontrolled, can lead to hypothermia due to impaired glucose regulation and decreased metabolic rate.
Medication Side Effects: Certain medications, such as sedatives, antidepressants, and antipsychotics, can increase the risk of hypothermia in the elderly by impairing the body's ability to regulate temperature.
Malnutrition: Malnutrition can lead to hypothermia due to decreased energy reserves and impaired metabolic function.

Sepsis: Sepsis can cause hypothermia, and it is essential to consider this diagnosis, as it can be life-threatening if not promptly treated.
Myxedema Coma: Myxedema coma is a life-threatening complication of hypothyroidism that can cause hypothermia, and it requires immediate medical attention.
Adrenal Insufficiency: Adrenal insufficiency can cause hypothermia, and it is crucial to consider this diagnosis, as it can be fatal if not treated promptly.
Stroke or Intracranial Hemorrhage: Stroke or intracranial hemorrhage can cause hypothermia due to impaired brain function, and it is essential to consider this diagnosis, as it can be life-threatening.

Pituitary Apoplexy: Pituitary apoplexy is a rare condition that can cause hypothermia due to impaired pituitary function.
Wernicke's Encephalopathy: Wernicke's encephalopathy is a rare condition caused by thiamine deficiency, which can lead to hypothermia.
Neuroleptic Malignant Syndrome: Neuroleptic malignant syndrome is a rare but life-threatening condition caused by certain medications, which can lead to hypothermia.