Glucose Control Key With COVID-19 in Diabetes, Say Experts

Renee Matthews

March 18, 2020

Editor's note: Find the latest COVID-19 news and guidance in Medscape's  Coronavirus Resource Center.

Patients with diabetes may be at extra risk for coronavirus disease (COVID-19) mortality, and doctors treating them need to keep up with the latest guidelines and expert advice.

Most health advisories about COVID-19 mention diabetes as one of the high-risk categories for the disease, likely because early data coming out of China, where the disease was first reported, indicated an elevated case-fatality rate for COVID-19 patients who also had diabetes.

In an article published in JAMA, Zunyou Wu, MD, and Jennifer M. McGoogan, PhD, summarized the findings from a February report on 44,672 confirmed cases of the disease from the Chinese Center for Disease Control and Prevention. The overall case-fatality rate (CFR) at that stage was 2.3% (1,023 deaths of the 44,672 confirmed cases). The data indicated that the CFR was elevated among COVID-19 patients with preexisting comorbid conditions, specifically, cardiovascular disease (CFR, 10.5%), diabetes (7.3%), chronic respiratory disease (6.3%), hypertension (6%), and cancer (5.6%).

The data also showed an age-related trend in the CFR, with patients aged 80 years or older having a CFR of 14.8% and those aged 70-79 years, a rate of 8.0%, while there were no fatal cases reported in patients aged 9 years or younger (JAMA. 2020 Feb 24. doi: 10.1001/jama.2020.2648).

Those findings have been echoed by the U.S. Centers of Disease Control and Prevention. The American Diabetes Association and the American Association of Clinical Endocrinologists have in turn referenced the CDC in their COVID-19 guidance recommendations for patients with diabetes.

Guidelines were already in place for treatment of infections in patients with diabetes, and at this stage, it seems that the same guidelines would extend to those patients who are also diagnosed with COVID-19, which is caused by the novel coronavirus, SARS-CoV-2.

In general, patients with diabetes – especially those whose disease is not controlled, or not well controlled – can be more susceptible to more common infections, such as influenza and pneumonia, possibly because hyperglycemia can subdue immunity by disrupting function of the white blood cells.

Glucose control is key

An important factor in any form of infection control in patients with diabetes seems to be whether or not a patient's glucose levels are well controlled, according to comments from members of the editorial advisory board for Clinical Endocrinology News. Good glucose control, therefore, could be instrumental in reducing both the risk for and severity of infection.

Paul Jellinger, MD, of the Center for Diabetes & Endocrine Care, Hollywood, Fla., said that, over the years, he had not observed higher infection rates in general in patients with hemoglobin A1c levels below 7, or even higher. However, "a bigger question for me, given the broad category of 'diabetes' listed as a risk for serious coronavirus complications by the CDC, has been: Just which individuals with diabetes are really at risk? Are patients with well-controlled diabetes at increased risk as much as those with significant hyperglycemia and uncontrolled diabetes? In my view, not likely."

Alan Jay Cohen, MD, agreed with Dr. Jellinger. "Many patients have called the office in the last 10 days to ask if there are special precautions they should take because they are reading that they are in the high-risk group because they have diabetes. Many of them are in superb, or at least pretty good, control. I have not seen where they have had a higher incidence of infection than the general population, and I have not seen data with COVID-19 that specifically demonstrates that a person with diabetes in good control has an increased risk," he said.

"My recommendations to these patients have been the same as those given to the general population," added Dr. Cohen, medical director at Baptist Medical Group: The Endocrine Clinic, Memphis.

Herbert I. Rettinger, MD, also conceded that poorly controlled blood sugars and confounding illnesses, such as renal and cardiac conditions, are common in patients with long-standing diabetes, but "there is a huge population of patients with type 1 diabetes, and very few seem to be more susceptible to infection. Perhaps I am missing those with poor diet and glucose control."

Philip Levy, MD, picked up on that latter point, emphasizing that "endocrinologists take care of fewer patients with diabetes than do primary care physicians. Most patients with type 2 diabetes are not seen by us unless the PCP has problems [treating them]," so it could be that PCPs may see a higher number of patients who are at a greater risk for infections.

Ultimately, "good glucose control is very helpful in avoiding infections," said Dr. Levy, of the Banner University Medical Group Endocrinology & Diabetes, Phoenix.

For sick patients

Guidelines for patients at the Joslin Diabetes Center in Boston advise patients who are feeling sick to continue taking their diabetes medications, unless instructed otherwise by their providers, and to monitor their glucose more frequently because it can spike suddenly.

Patients with type 1 diabetes should check for ketones if their glucose passes 250 mg/dL, according to the guidelines, and patients should remain hydrated at all times and get plenty of rest.

"Sick-day guidelines definitely apply, but patients should be advised to get tested if they have any symptoms they are concerned about," said Dr. Rettinger, of the Endocrinology Medical Group of Orange County, Orange, Calif.

If patients with diabetes develop COVID-19, then home management may still be possible, according to Ritesh Gupta, MD, of Fortis C-DOC Hospital, New Delhi, and colleagues (Diabetes Metab Syndr. 2020 Mar 10;14[3]:211-2. doi: 10.1016/j.dsx.2020.03.002).

Dr. Rettinger agreed, noting that home management would be feasible as long as "everything is going well, that is, the patient is not experiencing respiratory problems or difficulties in controlling glucose levels. Consider patients with type 1 diabetes who have COVID-19 as you would a nursing home patient – ever vigilant."

Dr. Gupta and coauthors also recommended basic treatment measures such as maintaining hydration and managing symptoms with acetaminophen and steam inhalation, and home isolation for 14 days or until the symptoms resolve. However, the ADA warns in its guidelines that patients should "be aware that some constant glucose monitoring sensors (Dexcom G5, Medtronic Enlite, and Guardian) are impacted by acetaminophen (Tylenol), and that patients should check with finger sticks to ensure accuracy [if they are taking acetaminophen]."

In the event of hyperglycemia with fever in patients with type 1 diabetes, blood glucose and urinary ketones should be monitored often, the authors wrote, cautioning that "frequent changes in dosage and correctional bolus may be required to maintain normoglycemia." Dr Rettinger emphasized that "hyperglycemia, as always, is best treated with fluids and insulin and frequent checks of sugars to be sure the treatment regimen is successful."

In regard to diabetic drug regimens, patients with type 1 or 2 disease should continue on their current medications, advised Yehuda Handelsman, MD. "Some, especially those on insulin, may require more of it. And the patient should increase fluid intake to prevent fluid depletion. We do not reduce antihyperglycemic medication to preserve fluids.

"As for hypoglycemia, we always aim for less to no hypoglycemia," he continued. "Monitoring glucose and appropriate dosage is the way to go. In other words, do not reduce medications in sick patients who typically need more medication."

Dr. Handelsman, medical director and principal investigator at Metabolic Institute of America, Tarzana, Calif., added that very sick patients who are hospitalized should be managed with insulin and that oral agents – particularly metformin and sodium-glucose transporter 2 inhibitors – should be stopped.

"Once the patient has recovered and stabilized, you can return to the prior regimen, and, even if the patient is still in hospital, noninsulin therapy can be reintroduced," he said.

"This is standard procedure in very sick patients, especially those in critical care. Metformin may raise lactic acid levels, and the SGLT2 inhibitors cause volume contraction, fat metabolism, and acidosis," he explained. "We also stop the glucagon-like peptide receptor–1 analogues, which can cause nausea and vomiting, and pioglitazone because it causes fluid overload.

"Only insulin can be used for acutely sick patients – those with sepsis, for example. The same would apply if they have severe breathing disorders, and definitely, if they are on a ventilator. This is also the time we stop aromatase inhibitor orals and we use insulin."

Preventive measures

In the interest of maintaining good glucose control, patients also should monitor their glucose levels more frequently so that fluctuations can be detected early and quickly addressed with the appropriate medication adjustments, according to guidelines from the ADA and AACE. They should continue to follow a healthy diet that includes adequate protein and they should exercise regularly.

Patients should ensure that they have enough medication and testing supplies – for at least 14 days, and longer, if costs permit – in case they have to go into quarantine.

General preventive measures, such as frequent hand washing with soap and water, practicing good respiratory hygiene by sneezing or coughing into a facial tissue or bent elbow, also apply for reducing the risk of infection. Touching of the face should be avoided, as should nonessential travel and contact with infected individuals.

Patients with diabetes should always be current with their influenza and pneumonia shots.

Dr. Rettinger said that he always recommends the following preventative measures to his patients and he is using the current health crisis to reinforce them:

  • Eat lots of multicolored fruits and vegetables.

  • Eat yogurt and take probiotics to keep the intestinal biome strong and functional.

  • Be extra vigilant regarding sugars and sugar control to avoid peaks and valleys wherever possible.

  • Keep the immune system strong with at least 7-8 hours of sleep and reduce stress levels whenever possible.

  • Avoid crowds and handshaking.

  • Wash hands regularly.

Possible therapies

There are currently no drugs that have been approved specifically for the treatment of COVID-19, although a vaccine against the disease is currently under development.

Dr. Gupta and his colleagues noted in their article that there have been reports of the anecdotal use of antiviral drugs such as lopinavir, ritonavir, interferon-beta, the RNA polymerase inhibitor remdesivir, and chloroquine.

However, Dr. Handelsman said that, as far as he knows, none of these drugs has been shown to be beneficial for COVID-19. "Some [providers] have tried Tamiflu, but with no clear outcomes, and for severely sick patients, they tried medications for anti-HIV, hepatitis C, and malaria, but so far, there has been no breakthrough."

Dr. Cohen, Dr. Handelsman, Dr. Jellinger, Dr. Levy, and Dr. Rettinger are members of the editorial advisory board of Clinical Endocrinology News. Dr. Gupta and Dr. Wu, and their colleagues, reported no conflicts of interest.

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