April 20 (Reuters) - Avanza Bank Holding Ab AVANZ.ST
* Operating income increased by 30 percent to SEK 225 million (SEK 173m), compared to mean average forecast 219 mln in Reuters poll
* Avanza bank Q1 profit after tax increased by 52 (44 %) per cent to sek 99 million
* Says expects a cost increase rate of 8-10 per cent for the full year, compared with the previously announced 6-8 per cent Source text for Eikon: ID:nWkrdq6996 Further company coverage: AVANZ.ST