Depression May Develop as Early as 5 Years After a Stroke

Lu Liu, PhD candidate

Credit: LinkedIn

A new study found 60% of stroke survivors developed depression within 18 years, which is a greater estimation than found in previous research.^1,2 In the same time frame, 22% of the general population experienced depression.

“Depression is common in stroke survivors but our research shows it persists for much longer than previously thought,” said investigator Yanzhong Wang, professor of statistics in population health at King’s College London, in a press release.²

Other studies examined the depression incidence in stroke survivors.³ For instance, a 2023 meta-analysis found among people who developed depression within 3 months following the stroke, 53% experienced persistent depression, and 44% recovered.3 The incidence of depression 3 – 12 months after a stroke was 9%.

Another study looking at the incidence of depression in stroke survivors after 18 years found more severe strokes were linked to more severe depressive symptoms 4 years after the stroke and those with more severe depressive symptoms at 4 years had a shorter survival rate.⁴

Due to the impact of post-stroke depression on quality of life, the study, led by Lu Liu, PhD candidate from King’s College London, assessed the incidence of mild and severe depression in the South London Stroke Register, a cohort of 6600 survivors of stroke in the Lambeth and North Southwark boroughs recruited between January 1, 1995, and July 31, 2019. ¹ The team aimed to determine the prevalence, incidence, duration, and recurrence rates of depression 18 years after the stroke.

The team used a score of >7 on the Hospital Anxiety and Depression scale to define depression at both 3 months and 18 months after the stroke. Investigators compared early-onset depression (3 months after stroke) with late-onset depression (1 year after stroke), as well as mild (scores > 7) and severe depression (scores > 10).

The study included 3864 who were assessed for depression at any point during the follow-up. The sample included 55.4% male, 62.5% White, and 29.7% Black. Additionally, participants skewed older with a median age of 68 years.

In total, 2295 patients had depression at some point during the follow-up, and 1569 did not. Investigators found severe depression developed early after a stroke, with 87.9% of participants developing depression within 5 years of having a stroke. The data suggests 5 years might be a good time for healthcare intervention.

However, for 2293 participants, they were diagnosed with depression just a year after their stroke. At the 18-year follow-up, 145 were diagnosed with depression.

The prevalence of post-stroke depression ranged from 31.3% to 41.5%), and the cumulative incidence of depression was 59.4% (95% confidence interval [CI], 57.8 – 60.9). Of the patients who developed post-stroke depression 3 months after their stroke, 46.6% recovered after 1 year. However, 66.7% of those who recovered experienced recurrent depression, and 94.4% of the recurrences happened within 5 years of the recovery.

The team saw this same trend after 1 year, with recovered depression returning. The recurrence rate at 1 year after recovery was greater in patients with severe depression (52.9%) compared to mild depression (23.5%) with a difference of 29.4% (7.6 – 51.2) (P = .003).

“With an aging population in the UK and an increase in the proportion of older adults, it’s essential we plan for rising healthcare demands to tackle the anticipated surge in stroke cases,” Wang said.²

Lu said in the press release depression can reduce the survival rate of stroke survivors, and it is crucial to improve their quality of life. Stroke survivors with depression may have a disrupted social life, less physical ability, and more inflammatory disorders—all of which can lead to an earlier death.

The team highlighted multiple limitations, including missing data in the follow-ups, patients with severe impairment were more likely to be excluded due to their inability to complete the depression assessment, and the number of participants followed up after 10 years was small.² Investigators stated other limitations such as how depression was not diagnosed with a clinical interview, possible variations of fieldworkers’ application process during the long follow-ups, the follow-up frequency changed in 2014 which could be attributed to missing data, and the Hospital Anxiety and Depression scale might not have been the right screening tool for stroke survivors.

“More clinical attention should be paid to patients with depression that is longer than one year because of the high risks of experiencing persistent depression,” Liu said.¹

^References

1. ^{Liu, L, Marshall, I, Pei, R. Natural history of depression up to 18 years after stroke: a population-based South London Stroke Register study. The Lancet. 2024. https://doi.org/10.1016/j.lanepe.2024.100882}
2. ^{More Needs to Be Done for Depressed Stroke Survivors As Incidence Climbs. EurekAlert! March 25, 2024. https://www.eurekalert.org/news-releases/1038588?. Accessed March 25, 2024.}
3. ^{Liu L, Xu M, Marshall IJ, Wolfe CD, Wang Y, O'Connell MD. Prevalence and natural history of depression after stroke: A systematic review and meta-analysis of observational studies. PLoS Med. 2023;20(3):e1004200. Published 2023 Mar 28. doi:10.1371/journal.pmed.1004200}
4. ^{Kellermann M, Berecz R, Bereczki D. Does the severity of depressive symptoms after stroke affect long-term survival? An 18-year follow-up. PLoS One. 2018;13(12):e0209157. Published 2018 Dec 18. doi:10.1371/journal.pone.0209157}