Q. We have a 16-year-old cat named Meow who lives up to her name. She cries all night long. She never used to do this, and it’s steadily been getting worse. We can sleep thanks to earplugs, but worry that she’s anxious or unhappy.

Nighttime vocalization is a common problem among senior cats. It’s one of many symptoms of cognitive decline. While some cats display signs of dementia such as pacing, disorientation and alterations in their sleep-wake cycles, others will meow –– sometimes very loudly.

For most, anxiety plays a big role. Hearing or vision loss can also contribute. Others, however, vocalize for no discernible reason.

That said, there are plenty of medical causes for this behavior, too. That’s why the first thing step is to have a veterinarian perform a full physical examination, blood work, and urinalysis.

Hyperthyroidism is one disorder that must be ruled out. When an ailing thyroid gland produces an excess of thyroid hormone, it can lead to restless behavior that’s easily mistaken for dementia-related nighttime vocalization.

Pain and the restlessness associated with finding a comfortable spot to rest is another possible. Anxiety related to a reduced status in the household’s feline pecking order can also elicit this behavior.

Once all medical causes have been ruled out, owners can address the anxiety associated with dementia. Your veterinarian can recommend medication or supplements that should help.

Dr. Patty Khuly has a veterinary practice in South Miami and blogs at dolittler.com. Send questions to khulyp@bellsouth.net, or Dr. Dolittler, Tropical Life, The Miami Herald, 1 Herald Plaza, Miami, FL 33132.