In a report published in the December 23, 2000, issue of the British Medical Journal (BMJ), researchers at the University of Liverpool in the United Kingdom write that hypoglycemia is one of the complications of diabetes most feared by patients. They point out, “Intensive research has been devoted to the development of hypoglycemia alarms.”
However, one thing we in the diabetes community might be overlooking is good ol’ reliable Rover.
In addition to being used by law-enforcement officials for sniffing out drugs and explosives, dogs are capable of guiding visually impaired people, as well as recognizing fits in people with epilepsy. The U.K. researchers believe that canine companions could also very well be the solution we have been looking for to detect low blood sugars, describing them as both “non-invasive” and a “fully bio-compatible and patient-friendly alarm system.”
“Hypoglycemia alarm dogs could provide an important aid to patients with poor awareness of symptoms, particularly those prone to [night-time] episodes or who live alone,” the BMJ paper stated.
The BMJ paper is not the first to address this phenomenon. In a 1992 issue of Diabetic Medicine (volume 9; supplement 2; S3-S4), researchers at the Bristol and Berkley Health Centre in Gloucestershire studied 50 people with diabetes who had owned pets since starting insulin. Thirty-eight percent of the people who owned dogs said their pooch responded to their hypoglycemic episode, by either barking or fetching a neighbor. This led the researchers to conclude, “Pets may help patients with type 1 diabetes through aiding them when hypoglycemic.”
Three Case Studies
In the paper prepared for BMJ, three diabetic women (whose reports were volunteered spontaneously and independently) and their faithful canine companions were evaluated.
Dog Hides Under a Chair When Owner Goes Low
The first case study involves a 66-year-old woman who developed type 2 diabetes in 1971. According to the BMJ paper, the woman was transferred to insulin in 1979 and currently takes injections of Regular and NPH twice daily, for a total of 38 units per day.
Despite having no significant diabetic complications or other illness and drinking very little alcohol, the woman reportedly has experienced “increasingly frequent hypoglycemic episodes the past two years,” commonly characterized by excessive sweating, generalized weakness, anxiety, and irritability. Most attacks occur in the evening, and some occur at night.
The 66-year-old woman during the past year has noticed, “unusual stereotyped behavior” by her nine-year old female mutt, Candy, prior to her having a low-blood-sugar episode. Candy’s behavior includes jumping up and down, running out of the room, and hiding under a chair in the hallway. Candy then re-emerges when the woman has taken a carbohydrate. The woman notes her BGs during such episodes are around 27 mg/dl.
“Wake up,” says Little Susie
The second case study involves a 47-year-old type 2 woman who takes 28 units of insulin each day. The woman has about two low-blood-sugar episodes per week, commonly characterized by sweating and sometime confusion. Her lows tend to occur during the afternoon and sometimes at night.
Within the past year, the woman’s seven-year-old female mutt, Susie, has shown “peculiar behavior during the patient’s hypoglycemic attacks.” The woman reports that Susie has nudged her awake. After awaking, the woman has tested to find herself having low blood sugar, usually around 36 mg/dl. Susie goes back to sleep only after the woman has taken a carbohydrate and her symptoms have settled.
Scratching the Bedroom Door
The third case study involves a 34-year-old type 1 woman who has suffered from retinopathy and kidney complications. She currently takes NPH and lispro, totaling 41 units per day. On average, she has two hypoglycemic episodes per week, characterized by sweating and light-headedness. The BMJ paper reports the woman has, “reduced awareness of hypoglycemia and does not wake up during nocturnal episodes.”
The woman’s three-year-old male golden retriever, Natt, becomes very distressed whenever she is hypoglycemic. During episodes of night-time hypoglycemia, he barks and scrabbles against the bedroom door and stops only after the woman’s hypoglycemia has been corrected. For the BMJ paper, the woman notes that her BGs on two such occasions were 29 and 34 mg/dl.
Taking Glucose Sensing to New Level
The BMJ authors say the three dogs reported here “take canine glucose sensing to a new level of sophistication.”
“All were clearly able to sense hypoglycemia accurately under circumstances when the patients themselves were initially unaware of falling glucose levels,” the paper states. “Formal calculations of sensitivity and specificity are not possible, but each dog showed [his or her] specific behaviors only when the patient had documented hypoglycemia.”
The BMJ authors say that Susie and Natt’s cases are unique because they detected low blood sugars even before their owners noticed the symptoms. Possible clues may include:
- Olfactory changes (possibly related to sweating)
- Muscle tremor
- Behavioral alterations, such as the patient’s failure to respond to his or her dog in the usual way.
The BMJ authors suggest an extended healthcare role should now be considered for man and woman’s best friend.
“Research is urgently needed to determine whether dogs can be trained to recognize and react to early signs of hypoglycemia.”
Who’s a Good Doggie?
Several Diabetes Health readers were not surprised by the article published in BMJ, saying that their faithful companions have always been there when low blood sugars have come around.
Courtney Newton of Erie, Pennsylvania, says that her step daughter, Becka, was diagnosed with type 1 diabetes in February 2000. Their dog is a Sheltie/Jack Russell mix named Dexter.
“Dexter is my baby and [has never sat] on the couch with anyone but me,” says Newton. “If I am not in the room, he sits on the floor.”
Shortly after Becka was diagnosed, however, Newton noticed Dexter sitting quietly on Becka’s lap, trying to lick her face. At first, Newton thought this odd and ignored it. She then realized it was Becka’s snack time, so she tested her blood sugar.
“She was only 48 mg/dl,” says Newton. “She was not aware of her low blood sugar. As soon as I fed her and got her blood sugars to come back up, Dexter was back on the floor laying in his usual spot.”
A couple of weeks later, Newton recalls, Dexter was again sitting on Becka’s lap around dinnertime, trying to lick her face. Newton asked Becka if she felt low and Becka said no. When Newton took Becka’s BG reading, however, sure enough, it was 52 mg/dl.
“I thought maybe it was just a coincidence, but the next time I saw [Dexter] sitting with [Becka] and licking her face, I immediately grabbed the meter even though it was not testing time,” says Newton. “She was 54 mg/dl that time. She had not felt any of these lows herself, but the dog had.”
Newton says it has been almost a year since these episodes. Every time Dexter is nearby and Becka is low, the dog licks some part of her body.
“Becka knows that if Dexter licks her incessantly, to test her sugar and tell me or her dad,” says Newton. “Every time he has licked her, she has been low. He seems to be able to pick up anything below 60 mg/dl.”
Gregor Randall of Grants, New Mexico, has had type 1 diabetes for 26 years. Randall’s dog, Maty, whom he has had almost four years, has awakened Randall for the last three years whenever his BGs have dropped low in the night.
“At first I thought it was just coincidence; however, it has happened too many times over the last three years,” says Randall. “I don’t know if I thrash, mumble, snore, or breathe differently when my blood sugar levels drop, but regardless, she is always pushing me with her paws.”
Randall says that when he does not quickly respond, Maty, who is 40 pounds, becomes aggressive. “[She takes] a running start and hits me with both her front paws.”
Mona Vicente is a type 1 from Odessa, Florida, who has been on an insulin pump for seven years. She says she experiences about five hypos per week, typically brought on by administering too much insulin. Vicente says her chow/sheepdog, Frosty, detects her bouts of oncoming hypoglycemia.
“Frosty was a lifesaver in waking me up when I was sleeping and incurring a low blood sugar,” says Vicente.
Ann Thelemann, a type 2 from Burnsville, Minnesota, raises Dobermans. A few months back, she noticed that her smallest dog, Hannah, would begin to cry and whine for no apparent reason.
“After a few weeks, I realized that just before I did my finger sticks, she began to whine and cry,” says Thelemann. After each stick, Thelemann noticed that she would be low. She says that Hannah would lay at her feet and wait for her to say it’s okay. “On days when I would tell her, ‘It’s not good today,’ she would bring me her rawhide chew.”
Thelemann says that Hannah never lets her oversleep or miss her next testing session.
Chet Woj, a 75-year-old type 2 from Alto, Texas, has five untrained dogs of various ages. Woj says that they stay with him when he is working on the ranch. Sometimes he goes a little low and begins to get dizzy.
“When I have a hypo and head for the truck, the young and middle-aged dogs follow and jump in excitement,” says Woj.
Feline Friends Have Protective Instincts Too
Deana Przybylski of East Lansing, Michigan, has had type 1 diabetes for 30 years. She says that dogs are not the only animals that have protective instincts for their diabetic owners.
“My cat, Angora, whom I’ve had for about 15 years, woke me up on one occasion by pawing at me and meowing to get my attention,” says Przybylski. “It was a time in my life before I was married and before I was in tight control, so I didn’t have very many lows.”
Przybylski says that after her cat awoke her, she discovered she was low. Przybylski got herself out of bed to get some juice.
Christine Moye of Detroit, Michigan, has both a dog and cat. Moye, who has had type 2 diabetes for 13 years, says her animals wake her up when her BGs go low at night.
“My dog uses his nose to wake me up, and the cat bites me,” she says. “They do this until I get up.”