Hello and welcome to a brand new series of the Zero to Finals podcast, where we're going to

be going through topics under the title of More Medicine, starting with psychiatry.

My name is Tom and in this first episode, I'm going to be talking to you about

depression. And you can find written notes on this topic at zero to finals.com slash depression

or in the psychiatry section of the zero to finals more medicine book, which should be available hopefully later this

year, if not at the beginning of next year. So let's get straight into it. Depression is a disorder

that causes persistent feelings of low mood, low energy and reduced enjoyment of activities. It affects people of all ages and from all

backgrounds. Let's start with the basic pathophysiology. The pathophysiology of depression is not fully

understood and likely involves a combination of complex mechanisms.

At least partially, it appears to involve a disturbance in neurotransmitter activity in the central nervous system,

particularly the activity of serotonin.

This makes sense considering that medications that boost serotonin are effective treatments for depression.

The cause of depression is often described as a chemical imbalance or low levels of serotonin,

which may be helpful as a simple explanation, but is probably overly simplistic.

Let's talk about the causes.

Depression may be triggered by life events,

for example the loss of a loved one.

However, it can occur without any apparent triggers.

It's thought to be caused by genetic, psychological,

biological and environmental factors.

Having an affected relative is a significant risk factor for developing depression.

Physical health conditions can trigger or exacerbate depression, and it commonly occurs with conditions such as stroke,

...