Efforts to control diabetes are more effective when patients have a detailed understanding of their blood-sugar levels in real time, which is why medical device companies like Medtronic and Abbott Laboratories are trumpeting benefits of their newest continuous glucose monitoring (CGM) systems.

Abbott said its FreeStyle Libre system can help patients reliably control their blood sugar at a lower cost than with "finger-stick" devices, while Medtronic said its new Sugar.IQ app and Guardian Connect sensor can generate predictive alerts up to an hour in advance of glucose problems using artificial intelligence.

Both systems are newly approved; Medtronic just started shipping its stand-alone system this month.

The companies presented their latest clinical and real-world data on CGM systems during the American Diabetes Association (ADA) annual meeting, which is taking place through Tuesday in Orlando.

Diabetes has quickly become the most expensive chronic health condition in the United States, accounting for $237 billion in direct medical costs last year and another $90 billion in lost productivity, according to a study prepared under the direction of the ADA.

As many as 25 million Americans have been diagnosed with diabetes, with more than 700,000 new cases appearing each year. Although diabetes can be controlled through changes in diet and exercise, many diabetics eventually end up taking prescription drugs and using medical devices to treat the condition.

The market for stand-alone CGM systems today stands at more than $1 billion in global sales and is growing at least 30 percent a year, Medtronic officials said.

Diabetes is a condition in which a person's body does not correctly use the sugars in his or her blood needed for energy, leading to a range of short-term and long-range problems. Many diabetics control their blood-sugar levels with multiple daily injections of insulin, the hormone that the body normally produces to break down blood sugars.

But synthetic insulin is a powerful drug. And unlike most medical conditions, patients (or their parents) are usually responsible for deciding how much of the drug to take in real time. People affected by diabetes have long sought the best ways to get the most reliable data on what's happening inside their own blood.

Toward that goal, medical device companies are putting more emphasis on developing accurate sensors that can be worn on the body for a week or so, giving up-to-the-moment readings that can be more dependable than using "finger-stick" devices that draw blood from the tip of a finger and then provide a glucose reading.

At the ADA Orlando meeting, Abbott highlighted the results of a meta-analysis of 17 past studies of "flash" glucose monitoring with its FreeStyle Libre device. The study-of-studies, based on real-world patients not recruited by Abbott, found that people who used the device had an average 0.56-point reduction in a measure called A1C, which looks at glucose control over time.

"From a glucose-control level, we are seeing a really strong relationship between people who check their glucose more often and their control," said Tim Dunn, director of clinical and computational research in Abbott's diabetes care business.

Another study at ADA examined the new, factory-calibrated FreeStyle Libre flash-monitoring system that was approved by the FDA last September, finding that people who used the wearable disposable sensor system would spend $120 less per month than if they did six finger pricks per day at standard prices.

Given how fast diabetes costs are rising, cost-effectiveness of diabetes therapies is an area of growing focus, Dunn said.

Medtronic, meanwhile, is entering the CGM market.

Medtronic has made headlines for its advanced MiniMed 670G insulin pump, which reads data from Medtronic's disposable, body-worn Guardian Connect sensor to automatically decide whether to adjust a patient's base rate of insulin delivery. Now that sensor is being sold as a stand-alone device so that patients can use it to calibrate manual insulin injections.

The Guardian Connect pairs with a free program from the Apple app store called Sugar.IQ, which uses artificial intelligence to examine a diabetic patient's current and past glucose readings to predict if glucose levels are going to be too high or too low.

Although other systems offer alerts up to 20 minutes in advance, Medtronic said its offers the only system that gives up to 60 minutes advance warning, which could be especially important for people who work for long hours high up on power lines or behind the wheel of semitrailer trucks. Some forms of insulin take more than 20 minutes to be effective.

The device also analyzes a person's past changes in glucose to detect patterns and then alert them if a high or low is coming. Using all of these features, 256 users of the system each spent an average of 36 minutes more per day within their desired blood-sugar range in a recent study, researchers at ADA said. The study found 86 percent of users rated the alerts as "helpful" vs. "not helpful."

"We are categorizing it as a smart CGM," said Laura Stoltenberg, general manager of the daily injection solutions business in Medtronic's Diabetes group. "We believe we are the first in the smart CGM category."