Diabetes alert dogs: a narrative critical overview.

Owing to their virtually incomparable olfactory apparatus and the mutual loving relationship with man, the use of dogs for assisting humans in many activities has become commonplace. Dogs have been used for long for livestock herding, hunting and pulling. More recently, they have been employed for servicing or assisting people with disabilities, for rescuing, for pet therapy and, last but not least, for detecting a vast array of volatile organic compounds related to drugs, narcotics, explosives and foods. Although cancer detection seems the most distinguished use of "man's best friends" in science and medicine, increasing emphasis is being placed on their capacity to perceive chemical changes or human expressions associated with harmful, even life-threating, blood glucose variations. The evidence available in the current scientific literature attests that diabetes alerting dogs (DADs) have a heterogeneous efficiency for warning owners of episodes of hypoglycemia or hyperglycemia, with sensitivities and specificities ranging between 0.29-0.80 and 0.49-0.96, respectively. Although the adoption of DADs seems effective for improving the quality of life of many diabetics patients, some important drawbacks can be highlighted. These typically include adoption and keeping expenditures, lack of certification or accreditation of dog providers, poor harmonization of training procedures, significant inter-breed, intra-breed and intra-dog variabilities, wide-ranging alert behaviors, ability of owners to identify dog's alerts, as well as lack of quality assessment of a dog's "diagnostic" performance. Overcoming many of these limitations shall probably make DADs more efficient tools for improving diabetes management.