Approximately one in eight older adults developed depression for the first time during the pandemic, according to a study conducted in Canada.

For those who had experienced depression in the past, the numbers were even worse, the study said. By the autumn of 2020 almost half (45 per cent) of this group of 20,000 older adults reported being depressed.

The researchers from University of Toronto analysed responses from the Canadian Longitudinal Study on Aging, which collected data from participants for an average of seven years, the study said.

"The high rate of first-onset depression in 2020 highlights the substantial mental health toll that the pandemic caused in a formerly mentally healthy group of older adults," said first author Andie MacNeil, University of Toronto.

While the surge in prevalence of depression among older adults during the pandemic is well known, few studies prior to this have identified the percentage of people who experienced it for the first time or the percentage of people with a history of the disorder who experienced a relapse, the study published in the International Journal of Environmental Research and Public Health said.

"The devastation of the pandemic which upended so many aspects of daily life hit those with a history of depression particularly hard," said co-author Sapriya Birk.

"Health professionals need to be vigilant in screening their patients who had mental health problems at an earlier time in their life," said Birk.

The researchers identified several factors that were associated with depression among older adults during the pandemic, including inadequate income and savings, loneliness, chronic pain, trouble accessing healthcare, a history of adverse childhood experiences, and family conflict, the study said.

Older adults who, prior to the pandemic perceived their income to be inadequate for satisfying their basic needs, and those who had fewer savings were more likely to develop depression during the pandemic, the study said.

"These findings highlight the disproportionate mental health burden borne by individuals with low socioeconomic status during the pandemic. "Many of these socioeconomic risk factors may have been exacerbated by the economic precarity of the pandemic, particularly for individuals with fewer resources," said co-author Margaret de Groh.

According to the study, individuals who experienced various dimensions of loneliness, such as feeling left out, feeling isolated, and lacking companionship had approximately 4 to 5 times higher risk of both incident and recurrent depression.

"It is not surprising that the lock-down was particularly difficult for older adults who were isolated and lonely during the pandemic. Social connections and social support are essential for well-being and mental health. Better support and outreach are needed for those who are isolated," said co-author Ying Jiang.

Older adults in chronic pain and those who had trouble accessing their usual healthcare, medication or treatments were more likely to be depressed during the autumn of 2020, the study said.

"This finding underlines the importance of streamlining service provision to ensure less disruption of medical services when future pandemics arise," said co-author Professor Paul J. Villeneuve.

Also, according to the study, individuals with a childhood history of adversity were more likely to be depressed during the Autumn of 2020. Older adults who experienced family conflict during the pandemic had more than triple the risk of depression compared to their peers who did not.

"Family conflict is a major stressor that can impacts mental health even in the best of times. With the enforced close quarters of lockdown and the stress of the pandemic, there was considerable strain on many family relationships. The ensuing conflict was a major risk for depression," said senior author Professor Esme Fuller-Thomson, University of Toronto.