(Sharecast News) - Barclays beat analysts' profit estimates despite the hit to the lender's operations from Brexit-related uncertainty and volatility in markets.For the fourth quarter of 2018, the lender posted a 1% increase in profits before tax to reach £574m (consensus: £566m) on the back of a 2% rise in adjusted total income to £5.1bn.In particular, the lender saw impairments jump by 23% to £643m on the back of a deterioration both in its UK and US cards businesses and after a £150m top-up related to Brexit uncertainty.Neither was Barclays's investment bank arm immune to the volatility that hit international financial markets at the end of 2018, but it fared better than most of its rivals, with income at the lender's markets unit falling by just 2.5% to £945m.The full year dividend was set at 6.5p per share, which was in line with management's own guidance.-- More to follow --