An aggrandizer is a person who aggrandizes - who makes something great, enlarges, or increases.
An autobiography is written by the person the biography is about. So, no, I would say it is not the same as many autobiographries are fictionalized through aggrandization and/or poor memory.
overdramatization, exaggeration, aggrandization, amplification, ballyhoo, build-up, burlesque, caricature, carry too far, draw the longbow, exhaust, go overboard, go to extremes, go too far, hyperbole, idealation, know no bounds, lay it on, magnification, make much of, overaction, overappraisal, overassess,emt, overcalculation, overcarry, overcharge, overcount, overdevelop, overdo, overdraw, overdrive, overelaborate, overemphasize, overesteem, overestimate, overexercise, overexert, overexpend, overindulge, overlabor, overmeasure, overplay, overpraise, overprize, overrate, overreach, overreact to, overreckon, oversell, overspeak, overspend, overstate, overstrain, overstress, overstudy, overtask, overtax, overtrain, overuse, overvalue, overwork, pass all bounds, pile it on, protest too much, puff, stretch, stretch the truth, talk big, talk in superlatives, tout, travesty