According to new research from a British university, managing depression through psychological therapy is associated with a lower risk of stroke.
Study author Ms. Ms. Céline El Baou, of the University College London, says: “Our study suggests that improving mental health could also help physical health, especially in those aged under 60.
“People whose depression symptoms improved after therapy had a 10% to 15% lower risk of cardiovascular disease than those who did not improve. Comparable effects were found in similar studies investigating low fat diets.”
Research from the University of Galway shows that those with depressive symptoms have an increased risk of stroke for every symptom they have.
This study is the first of its kind to examine whether by reducing depression symptoms with psychological therapy is associated with a lower risk of any future cardiovascular events. The study included 636,955 adults over the age of 45 years old with depression who had completed a course of psychological therapy and did not have cardiovascular disease or dementia.
The average age was 55 years and 66 per cent were women. Details on psychological treatment, incidence of cardiovascular disease and death was obtained from national electronic health record databases in England and linked at the individual level.
Level of depression was assessed before and after therapy using the Patient Health Questionnaire-9 (PHQ-9) which gives a score of 0 (not at all) to 3 (nearly every day) for nine items including the likes of little interest or pleasure in doing things; feeling down, depressed, or hopeless; trouble falling or staying asleep, or sleeping too much.
Improvement in depression was defined as a reduction of 6 points or more in the PHQ-9 score and no worsening of anxiety, which was defined as an increase of 4 points or more on the Generalised Anxiety Disorder Scale) between the start and end of treatment.
Anxiety was included in the definition so that the outcome of therapy was not considered good if depression improved anxiety worsened.
Patients were followed for new onset all-cause cardiovascular disease, coronary heart disease, stroke and all-cause mortality. Follow up commenced one year after the last therapy session and those with a cardiovascular event during this period were excluded to reduce the risk that previously undiagnosed disease was the cause of depression.
During an average follow up of 3.1 years, depressive symptoms were in improved in 373,623 (59 per cent) of participants and did not improve in 263,332 (41 per cent). There were 49,803 cardiovascular events and 14,125 participants passed away.
Improvement of depression was associated with 12 per cent lower risk of stroke versus no improvement.
The analyses were adjusted for characteristics that could influence the relationships such as age, ethnicity, gender, socioeconomic deprivation and other health conditions.
All associations were stronger in 45 to 60 year-olds, depression improvements were linked with a 15 per cent fall in the risk of cardiovascular disease compared to no improvement; the equivalent figure for those 60 years and over was 6 per cent.
Additionally, 45 to 60 year-olds with improved depression had a 22 per cent decreased risk of death during follow up compared to not improving, whilst those over 60 had a 15 per cent reduction.
Ms. El Baou says: “The findings are consistent with previous research suggesting that interventions to modify risk factors for cardiovascular disease are more effective at a younger age. This highlights the value of receiving help early to gain the most benefit.”
The authors do note, however, that these results do not definitively prove that reductions in cardiovascular disease were caused by the relief of depression. Data was also missing on lifestyle behaviours such as smoking and lack of exercise which could raise susceptibility to cardiovascular disease and limit the effect of psychological treatment.
Ms. El Baou says: “Our findings emphasise the importance of making psychological treatments more widely available and accessible to enhance mental and physical health. This is especially relevant for certain groups who face barriers to accessing psychological therapies and are at greater risk of cardiovascular disease. Collaborative care systems where specialists from both disciplines work together could be one way to make treatment more accessible and obtain better outcomes overall.”
