Catasys Inc., a digital health analytics company based in Brentwood, reported a $4 million loss in the second quarter despite a jump in billings and enrollment.

The company reported Aug. 14 a net loss of $4.2 million ($0.26 per share) in the second quarter ended June 30, compared to net income of $13.9 million ($0.97 per share) during the same period last year.

Shares in CATS fell 7.2 percent to $8.13 at the close of the markets a day after the announcement.

Catasys provides predictive analytics through its OnTrak system to reduce the cost of health insurance claims by determining candidates and treatment for substance use disorder, anxiety, and depression. It serves seven health plans in 20 states.

The company reported second quarter year-over-year enrollment of 289 percent, with a 152 percent jump in billings. It also reported “structural billing issues” with a major client that resulted in lower revenue.

Catasys, founded in 2000, has roughly 90 employees and a market cap of $129 million.

Health business reporter Dana Bartholomew can be reached at [email protected]. Follow him on Twitter @_DanaBart.