Cablevision Systems (CVC) swung to a first-quarter loss amid higher costs and declining cable-television revenue.

The cable television operator, which said it continues to rebound from the impact of Hurricane Sandy, has undergone restructuring by spinning off AMC Networks (AMCX) in 2011 and agreeing to sell its western U.S. cable systems, Optimum West, to Charter Communications (CHTR) for roughly $1.6 billion in cash. Cablevision also announced last month a deal to sell most of its Clearview Cinemas movie theaters to Bow Tie Cinemas.

In the latest period, the Bethpage, N.Y.-based company saw a $16.1 million loss, or 6 cents a share, versus a profit of $57.2 million, or 24 cents a share, in the year-ago period.

Revenue fell 0.8% to $1.52 billion, as cable television revenue slipped 0.7% on higher programming and employee costs.

Analysts expected per-share earnings of 4 cents on revenue of $1.55 billion. Operating margin narrowed to 6% from 16%.

Cablevision said it added 5,200 customer relationships in the period, while its high-speed data and voice segments each gained 22,800 customers.

Average monthly cable television revenue per video customer rose to $156.34 compared to $154.28 a year earlier.

The company anticipates a positive impact in the current quarter from an improved advertising outlook, Cablevision President and Chief Executive James Dolan said in a statement.

Shares were trading 7.3% lower at $14.34 Thursday afternoon.

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