* Altice France Q1 adjusted EBITDA up 2 pct
* Preliminary results issued in regulatory filing
* Shares reverse earlier losses (Adds details, shares reaction)
By Mathieu Rosemain and Gwénaëlle Barzic
PARIS, April 30 (Reuters) - Shares in telecoms and cable group Altice Europe rose on Tuesday after it disclosed that profits at its main French business improved over the first quarter.
Altice France's preliminary adjusted earnings before interest, tax, depreciation and amortization (EBITDA) grew 2 percent from a year earlier to 933 million euros ($1.1 billion), according to a regulatory filing.
The unexpected release related to a refinancing operation by Altice Luxembourg, the unit's direct holding.
The improvement at Altice France - which represents more than two-thirds of Altice Europe's profits - drove shares in the heavily indebted group higher, reversing earlier losses after French rival Orange warned over a prolonged price war in the market.
The stock was up 2 percent at 1407 GMT. The group's shares have gained 71 percent since the start of the year, valuing the company, which has a 28.8 billion-euro pile of debt, at 3.36 billion euros.
The Amsterdam-listed group founded by billionaire Patrick Drahi has flipped its strategy from cost-cutting towards gaining clients and selling infrastructure assets in a bid to lift its stock price after a sudden loss of investor confidence.
Altice France generated first-quarter revenue of 2.52 billion euros, down 3.1 percent from a year earlier.
The decline mainly stemmed from a fall in the average revenue per user (ARPU), a key metric within the telecoms industry, as the group sought to buy market share through heavy promotions.
Altice's Portuguese unit generated 509 million euros of revenue in the first quarter, up 0.4 percent from a year earlier, according to Altice Luxembourg's filing. Its adjusted EBITDA grew 1.4 percent to 206 million.
In total, Altice Luxembourg, which also regroups Altice's activities in Israel and the Dominican Republic, saw its sales fall by 1.7 percent to 3.47 billion euros over the January-March period. Its adjusted EBITDA dropped by 0.6 percent to 1.3 billion euros. ($1 = 0.8911 euros) (Reporting by Mathieu Rosemain and Gwenaelle Barzic; Editing by Sudip Kar-Gupta and Sarah White)