It may have some effect on the Atlantic but as I understand it El Nino and La Nina are mostly Pacific Ocean weather patterns. El Nino brings lots of rain to the west coast of the Americas (and California can use it). La Nina is the opposite - brings dry conditions. But someone should check my math.
The effects of those are felt worldwide.
Takes some research to determine what the weather was in areas during both La Nina and El Nino years.
Will find out that the UK and Europe has historically had nasty winter weather during La Nina years?