Once again it appears that the sensory systems of our pet dogs may be better than scientific equipment in monitoring changes in the health status of human beings. This time the target problem has to do with diabetes.
Diabetes is a chronic condition affecting more than 8% of Western populations (25.8 million adults and children in the US and 2.6 million in the UK). It is a life-threatening disease associated with the fact that the pancreas does not produce enough insulin resulting in overly high blood sugar levels (hyperglycemia). Untreated diabetes can result in cardiovascular damage, kidney failure, blindness, and other complications. To solve the problem of hyperglycemia the patient must take insulin, which drops the blood sugar level. Unfortunately the effects of a dose of insulin can be variable and unpredictable, and if the blood sugar level drops too far (hypoglycemia) it also places the patient's life in jeopardy if they fail to recognize their condition. With low blood sugar levels trembling, shakiness, poor mental concentration, slurred speech, and eventually loss of consciousness, coma, and even death can result. If the patient does recognize that they are entering a hypoglycemic state the solution is quite simple, involving simply eating some sugary food. The trouble is that it is estimated that around one in four people with diabetes do not recognize the early symptoms of hypoglycemia. For this reason frequent checks of their blood sugar level is necessary. Even with the practice of continuous monitoring of glycemic levels, a low blood sugar level can occur at night when the person is fast asleep and thus obviously not attending to any symptoms. In response to this diabetic patients often become quite anxious. This fear of a hypoglycemic event causes many patients to restrict their lifestyle and this profoundly reduces their psychological well-being and quality of life.
Some new research has been done at the University of Bristol which shows that dogs can be trained to monitor the levels of blood sugar in diabetes patients and they may be more effective than the traditional way of testing blood sugar levels involving drawing blood and obtaining a reading on a handheld monitoring device at intervals during the day. The researchers, Nicola Rooney, Steve Morant, and Claire Guest published the study in the journal PLOS One.
Since there is already evidence that the dog's nose is capable of performing some exotic and unusual feats (see here or here) these scientists started off with the belief that dogs could use their acute sense of smell to detect changes in a diabetic patient's sweat or breath which might reflect changes in the patient's blood sugar level. This was the rationale behind the training that was given to 17 dogs (including six Labrador retrievers, a golden retriever, two retriever crosses, a poodle, two labradoodles, a collie cross, a cocker spaniel and a Yorkshire terrier). The actual training was conducted by Medical Detection Dogs who collected scent from their target patients when these individuals were in a hypoglycemic state defined as a blood sugar level below a specified target value. The scent was collected in gauze pads which could then be used for training. Dogs were rewarded for alerting to the scent pads associated with hypoglycemia. The alerting behaviors involved whatever seemed to be most natural for each particular dog. Most commonly they involved licking, pawing, jumping, staring, whining or whimpering, or barking. However in one case a dog was trained to alert by fetching his owner's blood testing kit.
The diabetic patients in this study ranged in age from 5 to 66 years and were extensively interviewed as to the effectiveness of the dogs and the effect that they had on their lives. All of the patients reported positive outcomes, including fewer emergency call outs and reduced numbers of unconscious episodes. Furthermore they all reported improved independence since they felt more confident moving about the world with their hypoglycemic detection dogs by their sides. The patient-recorded data showed that the dogs alerted their owners with significant, although variable, accuracy when their blood sugar levels dropped significantly. Surprisingly, although not specifically trained to do so, several of the dogs also alerted when the patient's blood sugar levels became too high. Thus it appears that the dogs were somehow tuning themselves to detect deviations from normal glycemic levels, regardless of their nature.
The leader of the research team, Dr. Rooney, summarizes her results saying “These findings are important as they show the value of trained dogs and demonstrate that glycemia alert dogs placed with clients living with diabetes afford significant improvements to owner well-being, including increased glycemic control, client independence and quality of life. This potentially could reduce the costs of long-term health care.”
Of course such long-term benefits ultimately depend upon the traditional medical establishment accepting the fact that a sniff by a a Labrador retriever also can also be a valid medical lab test.
Stanley Coren is the author of many books including: The Wisdom of Dogs; Do Dogs Dream? Born to Bark; The Modern Dog; Why Do Dogs Have Wet Noses? The Pawprints of History; How Dogs Think; How To Speak Dog; Why We Love the Dogs We Do; What Do Dogs Know? The Intelligence of Dogs; Why Does My Dog Act That Way? Understanding Dogs for Dummies; Sleep Thieves; The Left-hander Syndrome
Copyright SC Psychological Enterprises Ltd. May not be reprinted, reposted without permission