Key Points
- A new study published in BMJ Mental Health has found that increasing age in adults with depression may be associated with a less favourable long-term clinical course.
- Researchers from Karolinska Institutet and Amsterdam University Medical Center examined 1,701 adults aged between 18 and 65 with depressive disorders, anxiety disorders or both.
- Participants were clinically assessed every two years over a six-year period as part of the Netherlands Study of Depression and Anxiety (NESDA).
- Depressive and anxiety symptoms generally declined over time, but the decline was slower among participants who were older.
- Older participants were more likely to experience a chronic course of depression.
- The age-related association was mainly driven by depression, with no indication of comparable age differences in the course of anxiety disorders.
- Adjusting for social circumstances, lifestyle, physical health and clinical factors that change with age did not explain the slower improvement in depressive symptoms.
- The researchers said the findings could point to a need for sustained clinical attention and potentially more age-adapted approaches to depression care.
- Federico Triolo said clinicians may need to be particularly attentive to persistent depression as patients become older, including closer follow-up and timely optimisation of treatment.
- The study was observational, so it cannot establish why depression appeared to have a less favourable course with increasing age.
- Because participants were aged no more than 65, the findings cannot automatically be applied to people in older age groups.
Amsterdam Times News (ATN) October 8, 2026 – A new study published in BMJ Mental Health has found that increasing age among adults experiencing depression may be associated with a less favourable long-term course of the illness. Researchers from Karolinska Institutet and Amsterdam University Medical Center found that depressive and anxiety symptoms generally declined over time, but the rate of improvement was slower as participants became older. Older participants were also more likely to experience a chronic course of depression. The researchers said the findings underline the importance of continued clinical attention to depression throughout adulthood, while stressing that age should not be regarded as determining an individual patient’s outcome.
The study examined 1,701 people aged 18 to 65 who had a current depressive disorder, anxiety disorder or both. Participants were followed for six years through the Netherlands Study of Depression and Anxiety (NESDA), with clinical assessments carried out every two years. The research found an age-related difference in the course of depressive symptoms, but the study could not establish the underlying reason for that association.
What did the new study find about age and depression?
The study found that depressive and anxiety symptoms tended to decline over time among the participants, but improvement occurred more slowly with increasing age.
The researchers also examined different possible courses of illness, including early remission, late remission, recurrence and chronic illness. Their analysis found that a chronic course became more common as age increased.
The association was primarily driven by depression rather than anxiety. According to the study findings, there was no indication of age-related differences in the course of anxiety disorders.
This distinction is significant to the findings because the researchers did not identify a general pattern in which increasing age affected the long-term course of every condition included in the study. Instead, the observed relationship was principally associated with depression.
The findings therefore point specifically towards differences in the longer-term course of depressive illness among adults of different ages within the study population.
How was the relationship between age and depression investigated?
Researchers examined 1,701 individuals between the ages of 18 and 65 who had a current depressive disorder, anxiety disorder or both.
The participants were drawn from the Netherlands Study of Depression and Anxiety, known as NESDA. The study followed participants over a six-year period, with clinical assessments taking place every two years.
This longitudinal approach enabled researchers to examine how symptoms and illness courses changed over time rather than assessing participants at only one point.
The researchers considered depressive and anxiety symptoms and also assessed whether individuals followed patterns including early remission, late remission, recurrence or a chronic course.
The analysis showed that symptoms generally became less severe over time, but the rate of decline in depressive and anxiety symptoms was slower among older participants.
The researchers then examined whether other factors associated with ageing could account for the observed relationship.
Could physical health and lifestyle explain the slower improvement?
The researchers investigated whether factors that can change with age might explain the slower decline in depressive symptoms.
These included social circumstances, lifestyle, physical health and clinical factors.
After taking these factors into account, the association between increasing age and slower improvement in depressive symptoms remained.
The study therefore did not find that these measured differences explained the age-related pattern.
The researchers said this could indicate that other processes associated with ageing may also have a role. However, because the study was observational, it does not establish what those processes might be or demonstrate that ageing itself causes a poorer course of depression.
This distinction is important when interpreting the results. The research identifies an association between increasing age and the course of depressive symptoms, rather than establishing a direct cause-and-effect relationship.
Why might the findings matter for depression treatment?
The researchers said the findings highlight the importance of sustained clinical attention to depression throughout adulthood, particularly as patients become older.
The results suggest that clinicians may need to remain attentive to the possibility of persistent depression among older adults rather than assuming that symptoms will necessarily improve at the same rate observed among younger patients.
Federico Triolo, one of the researchers, said age should not be interpreted as determining an individual patient’s outcome.
Triolo nevertheless said the results suggest clinicians may need to be particularly attentive to the risk of persistent depression as people age. He also indicated that closer follow-up and timely optimisation of treatment may be especially important.
The statement does not suggest that older age inevitably results in chronic depression. Rather, the research identifies an increased association with a chronic course within the population studied.
The researchers’ interpretation therefore places emphasis on continued clinical monitoring rather than treating age as a definitive predictor of an individual’s recovery.
What did the study find about anxiety disorders?
Although both depressive and anxiety symptoms were examined, the researchers found an important difference between the two conditions.
Symptoms of depression and anxiety generally declined over time, but the age-related pattern in the clinical course was mainly driven by depression.
The study found no indication of age differences in the course of anxiety disorders.
This means the findings should not be interpreted as showing that increasing age produces a poorer prognosis for anxiety disorders in the same way that the study observed for depression.
The distinction also reinforces the importance of considering different mental health conditions separately when examining how illness develops over time.
What did the researchers say about persistent depression in later adulthood?
The researchers emphasised that age should not be viewed as a factor that determines the outcome for an individual patient.
Instead, their findings suggest that clinicians should pay particular attention to the possibility of persistent depression as patients become older.
Triolo’s comments, as presented alongside the study findings, point towards closer clinical follow-up and timely optimisation of treatment where appropriate.
The implication is not that every older patient with depression will have a chronic illness. Rather, the study indicates that persistence became more common with increasing age among the participants examined.
The researchers therefore highlighted sustained clinical attention throughout adulthood as an important consideration.
What limitations did the researchers identify?
The study has limitations that affect how its findings should be interpreted.
Most importantly, the research was observational. This means that it identified relationships between age and the course of depressive illness but could not establish why those relationships existed.
The researchers therefore cannot conclude from the study that increasing age itself causes depression to improve more slowly or become chronic.
The analysis did account for a range of factors that vary with age, including social, lifestyle, physical health and clinical factors. However, these adjustments did not explain the slower decline in depressive symptoms.
The researchers suggested that other processes related to ageing could be involved, but the study did not establish precisely what those processes are.
Another limitation concerns the age range of the participants. The study included people aged from 18 to 65, meaning that the results cannot automatically be extended to people older than 65.
Consequently, the findings should be understood as applying to the adult population examined by the researchers rather than being treated as evidence about all older adults.
What does the study mean for adults living with depression?
The findings do not mean that an older person with depression is destined to experience a chronic course.
The researchers explicitly cautioned against interpreting age as determining an individual patient’s outcome.
Instead, the study indicates that, at population level, increasing age was associated with a slower decline in depressive symptoms and a greater likelihood of a chronic course.
For clinical care, the researchers highlighted the importance of sustained attention to depression throughout adulthood. Their comments also point towards the potential value of closer follow-up and timely treatment optimisation for patients who remain affected by depressive symptoms.
The findings therefore support continued assessment of the individual rather than relying on age alone when considering the likely course of illness.
What is the wider significance of the findings?
Depression and anxiety can follow long-lasting or recurring courses, making the factors associated with recovery and persistence important areas of research.
Previous research has produced conflicting findings about whether prognosis differs according to age. The new study addresses that uncertainty by examining participants repeatedly over six years rather than relying on a single clinical assessment.
Its results suggest that depressive symptoms may decline more slowly with increasing age and that chronic depression becomes more common as age increases within the studied population.
At the same time, the absence of an identified explanation means the findings do not resolve why the difference occurs.
The researchers’ conclusion therefore remains focused on clinical awareness and further understanding rather than establishing a single explanation for the observed relationship.
What is the background to this development?
The research was based on participants in the Netherlands Study of Depression and Anxiety, a study examining people with depressive and anxiety disorders.
For the new analysis, researchers considered 1,701 individuals aged 18 to 65 with a current depressive disorder, anxiety disorder or both. Participants underwent clinical assessments every two years during a six-year follow-up period.
The researchers examined changes in depressive and anxiety symptoms and assessed different illness courses, including remission, recurrence and chronic illness.
The analysis found that symptoms generally declined over time, but that the decline in depressive and anxiety symptoms was slower with increasing age. The association with a chronic course was mainly attributable to depression.
Researchers also assessed whether social, lifestyle, physical health and clinical factors that vary with age could account for the slower improvement in depressive symptoms. Those factors did not explain the observed association.
The study was published in BMJ Mental Health by researchers from Karolinska Institutet and Amsterdam University Medical Center.
What can be predicted about the impact on depression patients and clinicians?
For people receiving treatment for depression, the findings may reinforce the importance of continuing to monitor symptoms over time rather than assuming that improvement will follow the same course at every age.
For clinicians, the research may support particular attention to persistent depressive symptoms among older adults within the studied age range. The researchers specifically highlighted closer follow-up and timely optimisation of treatment as potentially important considerations.
However, the study does not establish that older age causes poorer treatment outcomes, nor does it show that every older person with depression will experience a chronic illness.
The results also cannot automatically be applied to people over 65 because that age group was not included in the study population.
