Is it depression or Alzheimer’s or both?

The overlap

Karen Miller | 5/18/2015, 6 a.m.
Some symptoms of depression are also symptoms of Alzheimer’s disease. Regardless of the cause, depression should be evaluated and treated.
Dr. Olivia Okereke is the academic director of the Geriatric Psychiatry Program at Brigham and Women’s Hospital. Photo courtesy Brigham and Women’s Hospital

No longer interested in activities you once enjoyed? Having trouble concentrating or remembering things? Sounds like a clear-cut case of depression. Not so fast, says Dr. Olivia Okereke, the academic director of the Geriatric Psychiatry Program at Brigham and Women’s Hospital. “Symptoms of depression and dementia overlap,” she explained. Especially in the early stages it can be hard to distinguish between the two. Further complicating the issue is that both often occur together.

Yet, these symptoms — regardless of the cause — are frequently overlooked in older adults. That’s because symptoms of Alzheimer’s disease are often considered normal signs of aging. In a recent survey conducted for the Alzheimer’s Foundation of America, two-thirds of caretakers who participated in the survey, reported that prior to the diagnosis, they believed the behavior of their loved ones was “just a normal part of aging.” Unfortunately, this misperception delayed the diagnosis for the majority of the patients.

Likewise, symptoms of depression are misunderstood, or even expected, in older adults. “Depression is not a normal part of aging,” explained Okereke.

Symptoms of depression

Is it depression or is it dementia?

  • Difficulty concentrating, remembering details and making decisions
  • Fatigue and decreased energy
  • Feelings of guilt, worthlessness and/or helplessness
  • Feelings of hopelessness and/or pessimism
  • Disturbances in sleep patterns
  • Irritability, restlessness
  • Loss of interest in activities or hobbies once pleasurable
  • Overeating or appetite loss
  • Persistent aches or pains, headaches, cramps or digestive problems that do not ease even with treatment
  • Persistent sad, anxious or "empty" feelings
  • Thoughts of suicide or suicide attempts

The symptoms that are highlighted tend to be correlated to both depression and dementia.

The consequences of both these conditions take a hefty toll. Mental health disorders, including depression and anxiety, are the sixth leading cause of disability in this county, as noted by the Council for Disability Awareness. As the population ages, the prevalence of AD is expected to climb. It strikes almost 50 percent of those aged 85 and older.

Yet, though different, scientists believe there is a relationship between depression and dementia. Researchers at Rush University in Chicago set out to prove that depression is actually a risk factor for dementia. They screened 1,700 older adults who did not have dementia or depression. The participants were re-evaluated every year for about eight years. During the course of the study fifty-two percent of the participants developed mild cognitive impairment, a less serious form of memory decline, while 18 percent developed dementia. Those who developed dementia had displayed more symptoms of depression before their diagnosis.

The link between depression and dementia is not clear. One theory is that depression and chronic stress may damage the brain.

Regardless of the cause of the symptoms the root of the problem must be established to ensure appropriate treatment. That’s where Okereke comes in. After a thorough medical and psychiatric evaluation she recommends a course of treatment that may include medication or counseling or both. A re-evaluation following the treatment will usually give the answer. “If mood improves and cognitive performance gets better, that would indicate depression is the main issue. If depression symptoms resolve, but performance does not change, the issue is likely more than a mood problem,” she said.