Explained | What is late-life depression and how can you navigate it? Premium

Late-life depression is verily treatable. The onus lies on us to take care of our elderly.

Psychiatrists are often asked if people become more depressed as they grow old. If yes, is depression more difficult to treat in old age? Late-life depression (LLD) is caused by multiple factors working together. It has three broad risk factors: biological, psychological, and social.

Scientists are yet to identify a candidate biomarker – a biological molecule in blood, body fluids, or other tissues, that is a sign of a disease process – for LLD. On the other hand, studies have found some evidence for genetic contribution to LLD. Scientists have also advanced several hypotheses involving the genes that code for serotonin synthesis, norepinephrine transporter, and the neurotrophic factor, but these ideas require more tests. A subset of LLD, called vascular depression, may be associated with cerebrovascular lesions.

Stress that accumulates over one’s life leads to a sustained secretion of cortisol, the hormone that regulates the body’s stress response. Increased cortisol levels lead to the loss of brain cells in the hippocampus, which is implicated in memory and learning. (This brain cell loss can be partially mitigated by the use of antidepressants.)

Researchers have proposed a vascular theory based on the observation that depression is a frequent outcome in people who have had a stroke. Vascular depression is associated with brain lesions, which appear as bright spots on brain scans. These spots, called white matter hyperintensities, disrupt brain signalling and brain circuits.

Heart attacks and heart conditions often lead to LLD, as do diabetes and hip fracture. Depressive symptoms can also manifest if a person doesn’t optimally recover from physical illnesses.

Personality attributes may colour the origin and expression of depressive symptoms in older adults. Neuroticism – the personality disposition to experience negative emotions, anger, irritability, and emotional instability – is consistently implicated in LLD.

Depressed individuals may overreact to life events or misinterpret them. Recent adverse life events (loss of a job, bereavement, etc.) are more frequently reported among depressed elderly people than among non-depressed older adults.