While we’ve known for decades that mental health shapes our physical well-being – and vice versa – researchers are still teasing out the specific circumstances and mechanisms that drive this symbiotic relationship. Now, an exhaustive new research project, covering more than 170,000 participants, reveals a strong link between depression and long-term physical health issues.
The researchers – from the Universities of Edinburgh and Dundee – found that middle-aged and older adults with a history of depression are much more likely to develop chronic health conditions and at a faster rate than their peers without depression.
Most of the existing research on mental and physical health conditions has been cross-sectional. These studies have revealed that roughly one in five people with a physical condition also have depression. And the more physical conditions someone has, the more likely they are to sink into depression.
That being said, cross-sectional studies remain challenging to decipher since depression and physical health might influence each other in both directions.
Cohort studies, on the other hand, have found (for the most part) that depression at the start of the study is tied to physical issues later on. But, these studies have some issues of their own. Many used surveys taken at different points, and sick survey participants might be more likely to drop out or die, which could skew the results.
Also, these studies typically looked at only a few physical conditions — between three and 15 — while a more recent study suggested expanding the scope to cover more than 50 conditions for a clearer measure of multimorbidity.
Study Overview and Methods
The latest study results, based on data pulled from the UK Biobank (UKB) cohort study, reinforce the urgent need for healthcare systems to consider more integrated approaches to managing mental and physical health outcomes at the same time.
The study’s authors combed through the participant data – whose ages varied between 40 and 71 years. Then, they tracked 69 long-term physical health conditions based on primary care, hospital, cancer registry, and death records. Nearly 18 percent of the participants had received a depression diagnosis before the study’s launch.
“At the start of the study, people without a previous diagnosis of depression had an average of two long-term physical health conditions, whilst people with a previous diagnosis had an average of three such conditions,” the researchers wrote.
Even after adjusting for sociodemographic factors, the participants with depression endured a 30 percent higher rate of physical health condition accrual.
The most common conditions included hypertension, allergic rhinitis, and osteoarthritis. Additionally, those with a history of depression showed elevated rates of anxiety and alcohol misuse.
Healthcare Implications
The results show (once again) that caregivers must recognize depression as a whole-body condition – spanning one’s mental and physical health.
“People who’ve experienced depression are more likely to develop long-term physical health conditions such as heart disease, diabetes and arthritis; however, existing healthcare systems are designed to treat individual conditions, instead of individual people with multiple conditions,” Usher Institute Statistician Kelly Fleetwood explained in a press release. “We need healthcare services to take an integrated approach to caring for people who have both depression and long-term physical health conditions.”
The study also underscores the importance of preventive care. Since modifiable risk factors like smoking, high body mass index (BMI), and low physical activity contributed to higher rates of physical illness among those with depression, interventions targeting these could curb future health complications.
This study also offers strong evidence that anyone with a history of depression is at greater risk of developing multiple long-term health conditions. The study’s authors call for healthcare systems to move past siloed treatments and instead adopt more integrated healthcare approaches.
Additionally, targeted preventive strategies addressing lifestyle risk factors could play a pivotal role in reducing the overall burden of multimorbidity.
As the prevalence of both depression and chronic illnesses continues to rise, adopting these integrated care models could help improve outcomes and reduce healthcare costs.
Further Reading
Mornings Set the Mood but Midday Can Bring You Down
