Hypothyroidism-related cognitive impairment: Hypothyroidism can cause cognitive symptoms, including memory problems and difficulty concentrating. This condition is a direct consequence of the thyroid hormone deficiency affecting brain function.

Sleep disorders: Sleep apnea, insomnia, or other sleep disorders can cause memory problems and confusion upon waking, especially in older adults.
Depression: Common in older adults and those with chronic conditions like hypothyroidism, depression can manifest as memory difficulties, among other symptoms.
Medication side effects: Certain medications, including those used to treat hypothyroidism or other common conditions in older adults, can have side effects that include memory problems.

Vitamin B12 deficiency: Although less common, a deficiency in vitamin B12 can cause neurological symptoms, including memory loss and confusion. It's crucial to diagnose and treat this condition to prevent permanent neurological damage.
Transient ischemic attack (TIA) or stroke: While less likely, sudden onset of memory difficulty could be a sign of a TIA or stroke, especially in older adults. Prompt diagnosis and treatment are critical to prevent further brain damage.
Infections: Certain infections, such as urinary tract infections (UTIs) in older adults, can present with confusion and memory problems as primary symptoms.

Creutzfeldt-Jakob disease: A rare, degenerative, fatal brain disorder that can cause memory loss, among other neurological symptoms.
Normal pressure hydrocephalus (NPH): Characterized by the buildup of cerebrospinal fluid in the brain's ventricles, leading to increased pressure and symptoms that can include memory problems, difficulty walking, and urinary incontinence.
Chronic traumatic encephalopathy (CTE): A rare condition associated with repeated blows to the head, leading to brain damage and symptoms that can include memory loss, confusion, and difficulty with coordination and balance.