New research suggests that keeping blood sugar extremely stable may carry an unexpected downside for some people with diabetes.
The findings, which will be presented at the Annual Meeting of the European Association for the Study of Diabetes (EASD) in Milan, Italy (September 28 to October 2), indicate that people with type 1 or 2 diabetes sometimes reported better quality of life after days when their glucose levels fluctuated more, as long as those levels were kept within safe limits.
The researchers combined data from continuous glucose monitoring (CGM) devices with daily wellness assessments. Their results suggest that the effort and restrictions required to minimize each glucose fluctuation could make it difficult for some people to enjoy everyday activities.
The research was carried out by Professor Dominic Ehrmann of FIDAM (Research Institute Diabetes Academy Mergentheim), Bad Mergentheim, Germany, and his colleagues.
Looking beyond blood sugar numbers
Helping people with diabetes maintain a good quality of life is an important part of treatment. Blood sugar control is important, but researchers also want to understand how daily diabetes management affects mood, energy, sleep, stress, and the ability to participate in normal activities.
The new analysis examined whether glucose patterns recorded by CGM devices were associated with daily quality of life among people with type 1 and type 2 diabetes.
The data come from the PRO-MENTAL study, funded by the German Center for Diabetes Research (DZD). Participants rated their quality of life every day for 14 consecutive days using a technique known as ecological momentary assessment (EMA) based on the WHO-5 questionnaire.
The questionnaire asks participants to rate five statements:
- I have felt happy and in a good mood.
- I have felt calm and relaxed
- I have felt active and vigorous.
- I woke up feeling fresh and rested.
- My daily life has been full of things that interest me.
The researchers also collected daily information on sleep quality, perceived stress, mood, and energy using the same EMA approach.
24-hour glucose monitoring
CGM data from the same 14-day period allowed the team to examine several measures of glucose control. These included blood sugar time below the safe range (TBR: 180 mg/dl), time in the normal range (normoglycemia) (TING: 70-140 mg/dl), and glucose variability.
Glucose variability reflects how much a person’s blood sugar rises and falls over time.
The researchers then used statistical models to determine whether one day’s patterns of glucose, sleep, stress, mood, and energy could predict the next day’s quality of life.
They also performed a separate analysis to see if same-day measurements were associated with that day’s quality of life. The models took into account age, sex and type of diabetes. They also included quality of life from the previous day to ensure it did not greatly influence the results.
400 people with diabetes participated
The analysis included data from 400 people with diabetes (72% type 1 diabetes, 28% type 2 diabetes, 55% women, age 47 years (range 32-63 years), mean glycated hemoglobin (HbA1c, a measure of blood sugar control) 7.6%.
Two glucose patterns stood out.
Spending more time in the normal glucose range on one day was significantly associated with better quality of life the next day. But most surprising is that greater glucose variability the previous day was also related to higher quality of life the next day.
In contrast, the amount of time participants spent above or below the safe glucose range the previous day was not significantly associated with their quality of life the next day.
Better sleep the night before was also linked to better well-being the next day. The same was true for higher energy levels the previous day (when asked how energetic the person felt on a scale of 0 [not at all] to 10 [very much].
Interestingly, same-day glucose measurements were not associated with quality of life that day.
A possible cost of trying to keep glucose too stable
The results do not suggest that poor glucose control is beneficial. In fact, spending more time within the normal range was associated with better quality of life.
Instead, the researchers say the finding related to glucose variability may point to a different problem. People who work especially hard to eliminate normal fluctuations can sometimes impose restrictions on themselves that make everyday life less enjoyable or certain activities seem more difficult to do safely.
The authors say: “Days with longer time in the safe normal range of blood sugar were followed by days when people with type 1 and type 2 diabetes reported better quality of life, underscoring the importance of optimal blood sugar control for well-being.
“Interestingly, higher than usual glucose variability was also associated with better next-day quality of life. These findings may suggest that people experience lower quality of life when they try to minimize glucose fluctuations too strictly, potentially due to the associated burden or restrictions in daily life, which may contribute to some people living with diabetes feeling unable to perform certain activities safely.”