Summary: A new research study suggests that older adults who suffer from symptoms of depression have a smaller brain and a 55% greater likelihood of developing vascular lesions in the brain versus those who don’t suffer from depression.
According to a new study published in the May 9th issue of Neurology older adults who suffer from depression may suffer from more extensive memory problems. The study also revealed the fact that older adults who suffer from depression may also have structural differences in their brains when compared to those who don’t suffer from depression.1
Study author Adin Zeki Al Hazzouri, Phd, MS, of the University of Miami Miller School of Medicine in Florida says, “since symptoms of depression can be treated, it may be possible that treatment may also reduce thinking and memory problems. With as many as 25 percent of older adults experiencing symptoms of depression, it’s important to better understand the relationship between depression and memory problems.”
There were 1,111 stroke-free individuals averaging 71 years of age involved in the study. Most were Caribbean Hispanic. Each participant underwent a brain scan, psychological exam and a variety of assessments for memory and thinking skills at the beginning of the study. Five years later their memory and thinking skills were retested.
Initial data showed that 22% of the participants had what would be considered greater symptoms of depression. This was defined as a score of 16 or higher on a test where scores could range from 0 – 60. A score of 16 or greater is considered at risk for clinical depression.
The test involved participants reporting how often in the past week they agreed with certain statements. These included statements such as “I was bothered by things that usually don’t bother me” and “I did not feel like eating.”
After adjusting for age, race, anti-depressive medications and other variables, greater symptoms of depression were linked to worse episodic memory. The term episodic memory is defined as a person’s ability to remember specific experiences and events.
Scores on tests were lower by .21 of a standard deviation when compared to those who didn’t score high for symptoms of depression.
A difference in brain volume and size was also found in those with greater symptoms of depression. In addition, those with higher depression symptoms also had a 55% greater chance of having small vascular lesion in the brain.
The researchers didn’t find any evidence of a relationship between greater depression symptoms and changes in thinking skills over the five-year study.
“Small vascular lesions in the brain are markers of small vessel disease, a condition in which the walls in the small blood vessels are damaged,” said Zeki Al Hazzouri. “Our research suggests that depression and brain aging may occur simultaneously, and greater symptoms of depression may affect brain health through small vessel disease.”
This study provides information about depression and memory and thinking skills, particularly related to those of Hispanic descent. This population has been insufficiently studied in the past during studies related to this topic. Which according to the study’s author is unfortunate because they can be at increased risk of dementia later in life.
The authors also noted that the study did have a few limitations including the fact that the subjects had to be healthy enough to have an MRI. Which means that they may have been healthier than the general population. In addition, the study was done over five years which may not have given researchers enough time to identify meaningful changes in memory and thinking abilities over a longer period of time.