MINNEAPOLIS -- May 20, 2015 -- People with depression may be more likely to develop Parkinson’s disease, according to a large study published in the May 20, 2015, online issue of the journal Neurology.

 

“We saw this link between depression and Parkinson’s disease over a timespan of more than two decades, so depression may be a very early symptom of Parkinson’s disease or a risk factor for the disease,” said Peter Nordström, PhD, Umeå University, Umeå, Sweden.

 

The researchers also examined siblings, and found no link between one sibling having depression and the other having Parkinson’s disease.

 

“This finding gives us more evidence that these 2 diseases are linked,” said Dr. Nordström. “If the diseases were independent of each other but caused by the same genetic or early environmental factors, then we would expect to see the two diseases group together in siblings, but that didn’t happen.”

 

For the study, researchers started with all Swedish citizens aged 50 years and older at the end of 2005. From that, they took the 140,688 people who were diagnosed with depression from 1987 to 2012. These people were then matched with 3 control participants of the same sex and year of birth who had not been diagnosed with depression, for a total of 421,718 control participants.

 

The participants were then followed for up to 26 years. During this time, 1,485 people with depression developed Parkinson’s disease (1.1%), while 1,775 people (0.4%) of those who did not have depression developed Parkinson’s disease.

 

Parkinson’s disease was diagnosed an average of 4.5 years after the start of the study. The likelihood of developing Parkinson’s disease decreased over time. People with depression were 3.2 times more likely to develop Parkinson’s disease within 1 year after the study started than people who did not have depression. By 15 to 25 years after the study started, people with depression were about 50% more likely to develop Parkinson’s disease.

 

People with more serious cases of depression were also more likely to develop Parkinson’s disease. People who had been hospitalised for depression 5 or more times were 40% more likely to develop Parkinson’s disease than people who had been hospitalised for depression only 1 time. People who had been hospitalised for depression were also 3.5 times more likely to develop Parkinson’s disease than people who had been treated for depression as outpatients.

 

The link between depression and Parkinson’s disease did not change when researchers adjusted for other conditions related to depression, such as traumatic brain injury, stroke, and alcohol and drug abuse.

 

SOURCE: American Academy of Neurology

MINNEAPOLIS -- May 6, 2015 -- People who eat a healthy diet with lots of fruits and vegetables, nuts, fish, moderate alcohol use, and not much red meat may be less likely to experience declines in their memory and thinking skills, according to a study published in the May 6, 2015, online issue of the journal Neurology.

 

“Adoption of a healthy diet probably begins early in life, and a healthy diet might also go along with adoption of other healthy behaviours,” said Andrew Smyth, McMaster University, Hamilton, Ontario.

 

For the study, 27,860 people in 40 countries were followed for an average of about 5 years. All participants were aged 55 years or older and had diabetes or a history of heart disease, stroke or peripheral artery disease. People who had experienced a recent stroke, congestive heart failure, and other serious conditions were not included in the study.

 

Participants’ thinking and memory skills were tested at the start of the study, after two years and after about five years. Participants were asked at the beginning of the study how often they ate certain types of foods, including fruits and vegetables, nuts and soy proteins, whole grains, deep fried foods and drank alcohol, as well as the ratio of fish to meat and eggs in their diet.

 

The study participants were followed until they experienced a myocardial infarction (MI), stroke, hospitalisation for congestive heart failure or death from cardiovascular disease or until the end of the study.

 

The thinking and memory tests yielded total scores with a maximum of 30 points. Participants were considered to have declined in their skills if their scores dropped by 3 or more points during the study. A total of 4,699 people had a decline in their thinking and memory skills.

 

People with the healthiest diets were 24% less likely to have cognitive decline than people with the least healthy diets. Among the 5,687 people with the healthiest diet, 782 (14%) had cognitive decline, compared with 987 (18%) of the 5,459 people with the least healthy diets.

 

The results were the same when researchers accounted for other factors that could affect the results, such as physical activity, high blood pressure, and history of cancer.

 

SOURCE: American Academy of Neurology