Study links brain lesions with depression in the elderly

French scientists have demonstrated a clear link between depression in the elderly and the presence of white matter lesions (WMLs) in the brain.

The researchers carried out cerebral magnetic resonance imaging (MRI) scans on over 1,500 people aged between 65 and 80. At the same time, they assessed the study participants for depressive
symptoms. Four years later, a follow-up MRI was carried out on a majority of the subjects. The researchers’ results are published in the journal Biological Psychiatry.

The MRIs revealed that people with a history of depression had a higher volume of white matter lesions than those with no history of major depression. Furthermore, these people’s lesions grew
faster during the four years of the study than other people’s.

For people with no history of depression, the presence of widespread white matter lesions at the start of the study was associated with an increased risk of developing depression during the
following four years.

WMLs are found when parts of the brain suffer from poor blood flow. Age and high blood pressure both increase the risk of developing lesions. For some time, researchers have wondered whether
depression in the over 65s could be linked to vascular problems such as high blood pressure, diabetes or high cholesterol.

‘Our study, which brings to light a link between white matter lesions and depression in elderly subjects, strongly reinforces the plausibility of the existence of a vascular-related depression
in older people,’ said Carole Dufouil of the French National Institute for Medical and Health Research (INSERM).

Depression among the elderly is a serious problem; in retirement homes, between 15% and 45% of the residents are thought to be affected. These latest results reinforce the importance of
addressing vascular risk factors in older people, the researchers note.