Dogs can act as an effective early-warning system for patients with diabetes, scientists have proved for the first time.

Research from the University of Bristol found dogs trained to respond to their owners' hypoglycaemia could alert them to impending lower blood sugars.

It was the first academic study to assess whether trained dogs could be reliably used to provide an early-warning system to monitor glycaemia control.

Glycaemia-alert dogs and specially trained pets were found to accurately and consistently detect the signs of low or high blood sugar in their owners.

The animals alerted their owners when their levels were outside their target range - reducing unconscious episodes, paramedic call outs and improving independence.

Dr Nicola Rooney, from the University of Bristol's School of Veterinary Sciences, is lead author of the paper, published in PLOS ONE.

"Despite considerable resources having been invested in developing electronic systems to facilitate tightened glycaemic control, current equipment has numerous limitations," Dr Rooney said.

"These findings are important as they show the value of trained dogs and demonstrate that glycaemia alert dogs placed with clients living with diabetes, afford significant improvements to owner well-being including increased glycaemic control, client independence and quality-of-life and potentially could reduce the costs of long-term health care."

The researchers collected data from the owners of 17 dogs trained by Medical Detection Dogs to assess whether the animals reliably responded to their owners' hypoglycaemic state. Results showed that since obtaining the dogs, all 17 patients reported positive effects.