Carpal Tunnel Syndrome: This condition is a common cause of hand numbness, especially at night, due to compression of the median nerve in the wrist. It is more prevalent in women and can be associated with activities that involve repetitive wrist flexion or extension.

Cervical Radiculopathy: Numbness in the hands can also be caused by nerve root compression in the cervical spine, which is common in older adults due to degenerative changes.
Ulnar Neuropathy: Compression of the ulnar nerve at the elbow or wrist can cause numbness, typically in the little and ring fingers.
Peripheral Neuropathy: This condition, often associated with diabetes, vitamin deficiencies, or alcohol abuse, can cause numbness in the hands and feet.

Thoracic Outlet Syndrome: Although less common, this condition involves compression of the nerves and/or blood vessels that pass into the thoracic outlet (the space between your collarbone and first rib), which can cause numbness in the hands.
Multiple Myeloma: A type of blood cancer that can cause peripheral neuropathy, among other symptoms. It's crucial to consider in older adults presenting with unexplained neuropathic symptoms.
Vitamin B12 Deficiency: Can cause peripheral neuropathy and is important to diagnose due to its potential for irreversible neurological damage if left untreated.

Amyloidosis: A group of diseases that can cause peripheral neuropathy due to the deposition of abnormal proteins (amyloid) in various tissues, including nerves.
Sjögren's Syndrome: An autoimmune disorder that can cause peripheral neuropathy, among other symptoms like dry eyes and mouth.
Lyme Disease: In its late stages, Lyme disease can cause neuropathy, although this would be less common in the presentation of isolated hand numbness at night without other systemic symptoms.