To Screen or Not To Screen Your Family Members for Type 1 Diabetes

To Screen, Or Not To Screen?

Weighing the odds of having loved ones screened for T1D
By, Gary Scheiner MS, CDCES

The screening process for Type 1 Diabetes

Screening for T1D is recommended for those with a first-degree relative who has auto-immune-induced T1D. 

This includes brothers and sisters, parents, and children of people with T1D.  The risk of developing T1D is markedly higher in this population:  Approximately 5% (one out of 20) first-degree blood relatives of people with T1D will develop T1D themselves.

Only one out of 300 people without a blood relative go on to develop T1D, so the risk is approximately FIFTEEN TIMES GREATER for those with a blood relative that has T1D.

So why doesn’t every blood relative receive treatment to prevent T1D?

Because we can identify those who are truly at high risk by measuring something called AUTO-ANTIBODIES.  These are molecules found in the bloodstream that turn the body’s immune system against us – in this case, against the beta cells of the pancreas.  The presence of specific antibodies raises the risk for developing T1D dramatically. These include:

• GAD65 antibodies
• Insulin antibodies
• IA-2 antibodies
• Islet Cell AAs
• Zinc transporter 8 AAs

How predictive are these antibody tests?

Plenty.  Those who test positive for just one of these antibodies has a 15% chance of developing T1D within the next 5 years.  For those who have two or more of these antibodies, the chances go up to 44% within the next 5 years, 70% within 10 years, and 84% within 15 years.  Bottom line:  If you have multiple antibodies, T1D is coming.

For those who test positive for antibodies, the screening process is usually followed up with a fasting blood glucose measurement, a 2-hour glucose tolerance test and an A1c.  Together, the results provide a pretty clear picture of where someone is in the “pre-T1D” stage.

The Benefits of Screening for Diabetes

Now that you understand the methodology behind the screening process, let’s discuss the all-important WHY. 

First, there’s a little thing called peace of mind.

For those who have ever worried about a loved one developing T1D, a negative screening result can put your mind at ease.  Periodic re-checks are recommended, but for at least a few years, you can rest easy.

What about a positive test?

Knowing that T1D is likely to develop in the years ahead allows you to prepare and keep an eye out for early warning signs.  Watching for physical symptoms (extra urination, thirst, unexplained weight loss, etc…) and doing an occasional fingerstick will allow you to catch T1D and begin treatment at the earliest possible stage. This has many important benefits:

1. The chance of being in ketoacidosis (DKA) at the time of diagnosis is sharply reduced
2. Inpatient hospitalization is rarely required at diagnosis
3. Unwanted symptoms of high glucose are minimized
4. In young children, there is less risk of extremely high glucose affecting brain function
5. (This is a big one!) Some pancreatic beta cells continue to function.  This allows for a prolonged honeymoon phase, decreased insulin requirements, and potentially easier/better glucose management for ten years or more after diagnosis!

By comparison, those diagnosed long after the initial onset of symptoms are at high risk of DKA, often require hospitalization, and have little to no remaining beta cell function – so any honeymoon period is short-lived.  Personally, I had ZERO honeymoon after my diagnosis, as I went for many months with symptoms before being diagnosed and treated.

Those who test positive for antibodies also have a chance to take control of things before T1D has a chance to progress to a diagnosable stage.  Lifestyle choices that help to improve the body’s sensitivity to insulin can lessen the workload on the pancreas.  This, in turn, has the potential to delay the development of T1D.

Lifestyle strategies that may be beneficial include:

• Regular exercise
• Modest (and low-glycemic-index) carbohydrate intake
• Stress management
• Adequate sleep
• Weight loss (if overweight)
• Avoidance of steroid medications

In addition, actions can be taken to lessen the chances of activating the body’s immune system. Strategies include:

• Prevention of illness/infection through sound personal hygiene
• Supplemental doses of Vitamin D

There are also injected/infused medications that have the potential to preserve beta cell function. These include:

• Abatacept (an immune system blocker commonly used to treat arthritis)
• GLP-1 Receptor Agonists (a common medication used to treat type-2 diabetes)
• Teplizumab (an immune system blocker used to protect transplanted organs)

Teplizumab (brand name Tzield) is now FDA-approved to delay the development of T1D in those at high-risk.  It has been shown to be particularly effective at protecting pancreatic beta cells from attack.  It is administered in a single round of treatment intravenously on a daily basis for two weeks.

The effectiveness of Tzield is unquestioned.  In clinical studies of those who tested positive for antibodies, the incidence of developing T1D in the first year was only 7% in Tzield recipients, as opposed to 44% in non-recipients.  On average, those who received Tzield remained T1D-free more than two years longer than those who did not receive it.  And if you don’t think two+ years is worth anything, consider how much progress has been made in T1D treatment in the past two years.  It also means two+ fewer years without T1D before a cure is found, which means less risk for long-term complications.

The total dose of Tzield given to those at risk of T1D is a fraction of what is used by those who receive organ transplants.  Nevertheless, some side effects have been reported.  About one in three recipients experienced a low lymphocyte count (which increases infection risk) and one out of three encountered a temporary rash on the hands.