* FTSEurofirst 300 up 0.1 pct, Euro STOXX 50 up 0.5 pct
* Insurer Aviva slumps 14 pct after slashing dividend
* Medium-term outlook bullish, more caution in short term
* Aggreko and Carrefour rise after reassuring results
By Sudip Kar-Gupta
LONDON, March 7 (Reuters) - European shares edged up in early trade on Thursday, pushing major indexes to near multi-year highs and with investors forecasting more gains in the medium term.
Gains across the market were expected to be more limited in the short term with the market awaiting a European Central Bank (ECB) meeting later in the day for clues on any ECB plans to help the weak economy and the bank's comments on Italy's political deadlock.
British insurer Aviva bucked the market, slumping 14 percent after slashing its dividend and was one of the biggest drags on the FTSEurofirst 300 index.
The pan-European FTSEurofirst 300, which had reached a 4-1/2 year intraday high of 1,193.35 points on Wednesday, rose 0.1 percent to 1,187.16 points.
The euro zone's blue-chip Euro STOXX 50 index advanced 0.5 percent to 2,692.02 points. And Germany's DAX rose 0.3 percent to 7,940.49 points, nearing five-year highs reached earlier this week.
British power company Aggreko and French supermarket retailer Carrefour led gainers on the FTSEurofirst 300 after posting reassuring results, with Aggreko shares surging 9.6 percent while Carrefour rose 5.5 percent.
Some investors expressed concerns over Europe's weak economy and a political stalemate in Italy, which has reignited fears over the ability of Italy and Spain to come up with reforms to tackle their debt problems and economic recession.
Strategists at investment firm Brown Advisory, which manages around $33 billion in client assets, said they were reducing their exposure to European shares.
"Brown Advisory is reducing exposure to European equities because it is sceptical about a continued run in 2013," said Brown Advisory asset allocation analyst Taylor Graff.
"Despite the recent rally, Brown still sees large macroeconomic risks, major fundamental growth obstacles and deteriorating stock valuations in comparison to the U.S. and other emerging markets," he added.
Clairinvest fund manager Ion-Marc Valahu said the broader upwards trend for European equity markets remained intact, and despite Aviva's dividend cut, solid results from the majority of Europe's top companies had bolstered investor confidence towards European equities.
Data from Thomson Reuters Starmine shows that 59 percent of companies on the STOXX Europe 600 index have reported results that either beat or met market expectations.
Valahu, whose main European fund is "overweight" on financial stocks, said expectations of a gradual recovery in the global economy and plans by central banks to keep supporting markets meant traders were increasingly having to unwind "short" bets that had forecast a fall in the market.
"It feels as if nothing can take this market down. People have given up on being 'short' because the market is moving away from them," he said.