A new study funded by Cancer Research UK has found that stopping smoking could help improve the symptoms of depression.

Carried out by researchers at Kings College London and the Charles University in Prague, together the team looked at 3775 patients attending a stop smoking clinic in the Czech Republic.

They found that smokers who received the clinic's specialist behavioral support and medication, 835 participants in total, were more likely to remain smoke-free for a year if they went back for repeat visits.

In addition, successful quitters also showed a large improvement in their depression, with two-thirds (66.3 percent) of those who had moderate or severe depression when smoking describing no or minimal symptoms of the condition during a one-year follow up.

Smoking rates among people with mental health conditions are more than double those of the general population in the UK -- around 40% vs. 20% -- with around three million of the 9.6 million adult smokers in the UK living with a mental health condition.

Smoking is also the single biggest factor contributing to a lower life expectancy in those with a mental health condition -- whose life expectancy is around 10-20 years lower than the general population.

However the team also noted that those with depression are less likely to quit successfully than those without the condition.

The team emphasizes that the findings highlight the importance of how the same support can benefit different groups to different extents, and that those with mental health problems may need some extra help to successfully quit.

Dr Leonie Brose, a Cancer Research UK fellow based at King's College London and senior author of the publication, also commented that, "While there's been an overall fall in smoking rates in recent decades, there hasn't been the same decline among people with mental health problems."

"The findings also suggest that giving up smoking may improve depressive symptoms, improving mental as well as physical health."

The results can be found published online in the journal Annals of Behavioural Medicine.