Having diabetes can turn into a slippery slope for the body’s health if left unchecked, according to a new study published in JAMA Psychiatry, which found that diabetes patients who developed symptoms of depression also began to show cognitive decline at faster rates.

Previous studies have shown that people with type 2 diabetes are more susceptible to depression, according to the American Diabetes Association, which says that nerve damage and trouble keeping blood sugar levels balanced could lead to feelings of being out of control. Furthermore, having diabetes puts patients at a higher risk of having a heart attack or stroke.

“Depression appears to be an important risk factor for dementia and cognitive decline among patients with diabetes,” Dr. Mark Sullivan, lead author of the study and professor of psychiatry at the University of Washington, told Reuters.

Diabetes, Depression, And Cognitive Decline

Sullivan and his team looked at type 2 diabetes patients who were part of the Action to Control Cardiovascular Risk in Diabetes-Memory in Diabetes (ACCORD-MIND) trial. Participants, who on average had diabetes for nine years, were tested on reaction times to stimuli, their ability to memorize words, and their ability to use memories to execute plans, pay attention, and inhibit behaviors. These abilities were tested along with their depressive symptoms at the beginning of the study, 20 months, and 40 months.

Of the 2,600 participants who completed the study, 18 percent began with depression, 17 percent became depressed during the study, and 62 percent exhibited no signs of depression during the entire study. Participants whose scores indicated depression “showed greater cognitive decline during 40-month follow-up on all tests,” the study authors write. Although cognitive decline does not necessarily mean someone will develop dementia or Alzheimer’s disease — the most common type of dementia — it does put people at a higher risk.

The study found that those who suffered from depression tended to be women, younger, non-Hispanic whites, and overweight or obese. They also had higher blood sugar levels and cholesterol than any other participants. Diabetes, depression and cognitive decline were associated even after accounting for other risk factors, such as age, gender, race, obesity, smoking, and alcohol use.

“Depression in patients with type 2 diabetes was associated with greater cognitive decline in all domains, across all treatment arms, and in all participant subgroups assessed,” the researchers write. “Future randomized trials will be necessary to determine if depression treatment can lower the risk of cognitive decline in patients with diabetes.”

Noticing Depressive Symptoms

The American Diabetes Association offers some ways to spot depression, which the organization says can often go unnoticed until they begin to interfere with diabetes care. Signs and symptoms include:

· Losing interest in activities you used to like.

· Change in sleep patterns, including being unable to fall asleep or waking up during the night.

· Waking up earlier than usual.

· Changes in appetite, including passing up on food altogether.

· Trouble concentrating because sad feelings get in the way.

· Loss of energy.

· Nervousness.

· Guilt that you aren’t doing something right, or feeling as if you’re a burden to others.

· Feeling worse during the morning than during the rest of the day

· Suicidal thoughts.

Source: Sullivan M, Katon W, Lovato L, et al. Association of Depression With Accelerated Cognitive Decline Among Patients With Type 2 Diabetes in the ACCORD-MIND Trial. JAMA Psychiatry. 2013.