Depression Scientific Research and New Treatments

Depression is a common mental health condition that affects millions of people worldwide. According to the World Health Organization (WHO), approximately 280 million people across the globe experience depression.

The symptoms of depression include a persistent low mood, feelings of sadness and hopelessness and a loss of interest in general life. Depression can cause people to become withdrawn, leading to loneliness and isolation. In extreme cases, people with depression may self-harm or commit suicide. More than 700,000 people die from suicide each year and it is one of the leading causes of death amongst 15- to 29-year-olds globally.

Depression and poor mental health are also among the leading reasons for working-aged people to be economically inactive. A new survey commissioned by the Royal College of Psychiatrists (RCPsych) found that 9% of adults had to take time off work due to mental ill health in the last year. Mental ill health is having a detrimental effect on economic productivity across multiple countries and leads to millions of lost working hours each year.

The symptoms of depression are typically treated using medication, therapy or a combination of the two. Some people find that making lifestyle changes, such as improving their diet or getting more exercise, also helps to improve their mental health.

In this article we will take a look at how research into depression may evolve treatment options and improve the quality of life for people who suffer mental ill health.  

What are the Current Challenges in Depression Treatment and Research?

Treatment gaps and limitations within depression treatment and research include:

• More patients presenting with treatment-resistant depression (TRD). TRD is a subset of major depressive disorder where patients do not respond adequately to frontline treatments (usually at least two types of antidepressant medication taken at the correct dose)
• A diagnosis of depression relies on subjective symptom reporting by the patient, leading to potential misdiagnosis, misunderstandings and delays in accessing help
• There is still a lack of understanding about how antidepressants, such as SSRIs, actually work and more research is needed into this area
• There may be a lack of training and understanding about mental health issues amongst GPs who are usually at the frontline of diagnosing and treating people who have depressive symptoms
• There is still a resistance to acknowledging the reality of depression and/or engaging with treatments (especially therapy) due to misunderstanding and stigma
• Young people and disadvantaged communities face additional barriers to accessing healthcare

Diagnosis and treatment services vary greatly between countries and also between areas within those countries. In the UK, for example, it is somewhat of a postcode lottery, with some areas of the country having waiting lists for talking therapies on the NHS that are over a year long. These discrepancies mean that there is a lack of equity amongst people with depression and often mean that people who are more affluent are more easily able to access help and treatment than those who are poor.

Due to the prevalence of depression and the devastating impact it can have on people’s lives, their wider communities and the economy, further work must be done within prevention, early diagnosis and treatment. This can only be achieved through innovation, collaboration and significant funding within the field of mental health research.

Important innovations that are necessary to improve outcomes include:

• A move towards more personalised treatments
• Improving understanding into depression on a deeper, biological level
• The rolling out of online therapeutic treatments to allow better access to therapy for those in rural or isolated areas or those who have mobility or transport issues
• Clear information to be more widely available regarding the safety and efficacy of alternative treatments for depression

Advances in Neurobiological Research

As we know, cases of depression and major depressive disorder (MDD) are increasing all over the world. Although it is widely accepted that depression is related to emotional and mental factors (such as stress or anxiety), research is ongoing to further understand how instances of MDD are influenced by other factors such as:

• Genetics
• Social stress
• Physical health
• Chronic disease

A number of important studies have been conducted in the field of neurobiology and depression and research is ongoing. This is an important area of study, especially in terms of providing patients with an accurate diagnosis. If objective and quantifiable biomarkers can be conclusively found in patients with depression, this may revolutionise both diagnostics and treatment options.

• In China, serum samples were taken from 48 depressive patients and compared with 48 healthy control patients in a recent study
• Scientific researchers studied the plasma proteomics in both groups and found that five potential biomarkers including TUBB, ITIH4, C3 and C4A differentiated between the depression patients and the healthy controls
• Although the samples were relatively small, this research proposes that there are potential biomarkers for depression that may help with forming a more objective diagnosis of the condition in the future

It is important to note that research into this topic is ongoing and complex and there is a diversity of opinion within the scientific community. A better understanding of brain chemistry in relation to depression could lead to earlier and faster diagnosis, better identification of at-risk individuals and more tailored treatment plans that don’t rely on self-reporting or a ‘trial and error’ style approach.

What is the Role of Genetics and Epigenetics in Depression?

Research suggests there is a genetic component to depression.

Although scientists have found that genetics and epigenetics play a role in depression it is important not to take a deterministic view on this:

• Although genetics can make certain individuals more ‘at risk’, it is vital that people do not become pessimistic, assuming they will definitely become depressed or that there is no possibility for prevention/intervention
• More research needs to be done into how people who are genetically at risk react to life stressors that can cause depression in comparison to people without those genetic markers. This will help to ascertain how far genetics alone are playing a role and how far they are a contributing factor
• People must continue to be encouraged to use help-seeking behaviour for themselves, even if they have no family history of depression

Emerging Therapies and Treatments

Psychedelic treatments

There is an increasing interest in the efficacy of using psychedelic treatments for depression.

Some psychedelic drugs, such as psilocybin and MDMA (ecstasy), have shown promise as therapies for some mental health conditions, including:

• Treatment-resistant depression
• Post-traumatic stress disorder (PTSD)

These drugs seem to work by increasing brain plasticity. This means that they encourage the growth of new connections between neurons in the brain. Exactly how these drugs increase plasticity is unclear, but with further research, if this could be understood, scientists may be able to manipulate the chemical compounds to create new drugs that have the same therapeutic effects but omit the hallucinogenic properties.

Microdosing

An increasing number of people are microdosing on a regular basis. This involves taking very small amounts of psychedelic substances (such as psilocybin or LSD). People report that this helps them to:

• Boost their mood
• Be more creative
• Feel less anxious

Whilst many of these benefits rely on people self-reporting, this is definitely an area worthy of further research within controlled conditions.

The role of the gut

Our brain and our gut are interconnected. People with depression often experience gut-brain dysfunction as well. This includes appetite disturbances, metabolic problems and nausea.

Some studies have found that certain gut bacteria are positively correlated with depression, while others are negatively associated. Our gut microbiome may be linked to poor mental health, due to imbalances in gut bacteria.

Probiotics can help us to maintain a healthy gut flora. More research needs to be done into the gut-brain symbiosis to find out whether probiotics may genuinely be a useful tool to boost mood and cognitive function and prevent depression.

Additionally, we now know that around 90% of the body’s serotonin is found in the gut. A new report indicates a direct correlation between gut dysbiosis, major depressive disorder and SSRI efficacy. Furthermore, it suggests that gut microbiota may serve as an indicator and a treatment target for major depressive disorder, which is certainly an area worthy of future exploration.

Transcranial Magnetic Stimulation (TMS) and Deep Brain Stimulation (DBS)

Transcranial Magnetic Stimulation (TMS) and Deep Brain Stimulation (DBS) are two different therapies that can be used to treat depression.

TMS:

• TMS is a non-invasive procedure that requires a device (sometimes called a depression helmet) containing electrical coils to be mounted onto a person’s scalp
• An electrical current is then passed through the coils which creates a magnetic field
• The magnetic fields stimulate deep neural networks within the brain
• In patients with depression the target area of the brain is usually the dorsolateral prefrontal cortex
• TMS is supposed to balance electrochemical activity within the brain which can stabilise mood and ease some of the symptoms of depression
• Sessions last around 20 minutes  

Studies show that TMS has a success rate of around 75% when it comes to treating depression.

DBS:

• DBS is a medical procedure that requires 2-3 surgeries under general anaesthetic
• During initial surgeries, a surgeon will place electrodes in the brain through two small holes in the skull
• In subsequent surgeries, a device is implanted beneath the skin that is connected to the electrodes via wires placed beneath the skin
• The device is then able to deliver an electrical current to parts of the brain
• DBS is used to treat a variety of conditions including epilepsy and Parkinson’s Disease; however, doctors are considering it as an option for treating mental health issues, including obsessive compulsive disorder (OCD) and severe depression that has not responded well to other treatments

Using DBS to treat mental health conditions is still in its infancy and further research is needed to determine its efficacy and safety. If you are considering DBS ensure that you are fully aware of the risks involved with having surgery so that you can give informed consent.

The Future of Digital Mental Health Tools

The link between depression and loneliness/isolation is being increasingly acknowledged. Technology allows us to be more connected than ever yet people are becoming increasingly lonely.

Digital mental health tools and the use of artificial intelligence (AI) have the potential to reduce the extent of loneliness and isolation among the population. However, many people have concerns about this, for example:

• Some people worry about the ethics of using AI
• Older people may not understand how to interact with technology or may be more resistant to it
• An increased reliance on digital tools may exacerbate mental health inequality – meaning impoverished people or those who live in areas where there is limited or unreliable internet coverage are left out

If digital tools and technologies are developed with ethics in mind and have undergone rigorous training for bias, how to spot misinformation, when to alert emergency services etc, there is no doubt that they have a place in the future of mental health treatment.

Addressing Societal and Global Trends

Certain aspects of the covid-19 pandemic, including concerns over vaccine safety, have damaged public trust in the scientific and medical community. This has made more people open-minded towards alternative treatments and self-help. There is a growing amount of research which suggests that lifestyle changes, certain activities and self-help behaviours do have a positive impact on mental health.

This includes:

• Nature therapy – research has shown that getting out in nature benefits mental health
• Healthy eating – depression has been linked to certain vitamin and mineral deficiencies, a lack of protein or a lack of omega-3 fatty acids
• Getting active – exercise boosts endorphins (feel good hormones) and improves mood. It also helps us to maintain a healthy weight and can improve our self-esteem and confidence levels

It is possible that, in future, there will be a significant shift away from simply writing a prescription for antidepressants, towards taking a more holistic approach to depression treatment. In such cases, medical professionals may need to learn how to strike a balance between patient safety and prescribing alternative treatments to medication when treating depression. For example, for serious cases of depression, a medical intervention will likely still be necessary, whereas in mild cases, using self-help and making positive changes may negate the need for taking antidepressant pills entirely.

Some people refuse to visit the doctor and would rather self-medicate with alcohol or illegal drugs. Cannabis is the most widely used drug across the world. People use cannabis to help them relax, help them to sleep better and even to manage pain. A number of countries, including Canada, Thailand and Uganda, have legalised recreational cannabis use nationwide. A growing number of countries are moving towards decriminalising or even legalising the use of cannabis for either medical or recreational use.

Medical marijuana is now legal in 38 US states and in 24 states marijuana is legal for recreational use. Some research has shown a correlation between cannabis use and mental health issues (including depression), therefore, this change in attitudes towards cannabis use may be of concern.

More research must be done into the relationship between using cannabis and mental health problems to discover whether the connection between the two is correlative or causal, in order to help people to make more informed choices about their drug use.

Prevention and Early Intervention: New Horizons

Developing new diagnostic tests that reveal people at risk of depression will help to prevent cases and also allow for earlier intervention.

Benefits of early intervention include:

• Better health outcomes for patients
• Reduces the onset of symptoms
• Increases the chance of recovery
• Reduces instances of relapse
• Increases trust between patients and health workers

Preventing illness is always more desirable than treating illness. Prevention is also more beneficial to the economy as it negates treatment costs, reduces burdens on health services and allows people to continue to function normally within society.

Strategies for preventing depression include:

• Programmes within schools and workplaces that focus on emotional resilience, self-care, preventing burnout and developing early coping mechanisms
• Nationwide initiatives that focus on wellbeing and positive lifestyle changes such as eating a balanced diet, reducing stress and getting enough sleep
• Ensuring equal access to resources, healthcare and education for marginalised groups
• Normalising conversations around mental ill health and encouraging help-seeking behaviour
• Global and/or social media campaigns featuring a collaboration from experts and famous figures/celebrities who can share narratives of their experiences with depression that resonate with the general public

Conclusion

Depression remains a prevalent mental health condition that stems from a complex interaction of biological, psychological, emotional and social factors. Despite the impact that depression can have on our lives, research into new and emerging areas holds immense promise for advancing treatment, diagnosis and prevention.

We encourage you to stay up to date regarding developments in mental health research, keep an eye out for scientific breakthroughs and remain optimistic about the future of depression care.