New research to be presented at the European Association for the Study of Diabetes (EASD) annual meeting in Milan suggests that glucose variability quality of life outcomes may move in the same direction under certain conditions, a finding that complicates the straightforward case for minimising every blood sugar fluctuation.
The study, from Professor Dominic Ehrmann of FIDAM (Research Institute Diabetes Academy Mergentheim) in Bad Mergentheim, Germany, and colleagues, will be presented at the EASD meeting running from 28 September to 2 October. It draws on data from the PRO-MENTAL study, funded by the German Center for Diabetes Research (DZD).
What the study actually measured
The analysis included data from 400 people with diabetes, 72% with type 1, 28% with type 2, 55% female, with a median age of 47 years (range 32 to 63) and a mean glycated haemoglobin (HbA1c) of 7.6%. Participants wore continuous glucose monitoring (CGM) devices and completed daily well-being assessments for 14 consecutive days using a method known as ecological momentary assessment, based on the WHO-5 questionnaire.
The World Health Organization‘s WHO-5 instrument asks participants to rate five statements covering mood, calm, vigour, sleep quality, and daily interest. Alongside these, participants also recorded sleep quality, perceived stress, mood, and energy levels on a scale from 0 to 10 each day.
On the CGM side, the researchers tracked time below range (TBR: below 70 mg/dl), time above range (TAR: above 180 mg/dl), time in normal glucose range (TING: 70 to 140 mg/dl), and overall glucose variability, meaning how much blood sugar rose and fell across the day. Statistical modelling then tested whether any of these glucose patterns, alongside sleep, stress, mood and energy, could predict quality of life on the following day.
The glucose variability quality of life paradox
Two findings stood out. The first is unambiguous: spending more time in the normal glucose range on one day was significantly associated with better quality of life the next day. That is the expected direction, and it reinforces the basic case for good blood sugar control.
The second finding is the one that will attract more scrutiny. Greater glucose variability on the previous day was also linked to higher next-day quality of life, even after the models accounted for age, sex, diabetes type, and the participant’s quality of life on the prior day. Time spent above or below safe glucose limits showed no statistically significant association with next-day quality of life, and same-day glucose measurements were not associated with that same day’s well-being at all.
Better sleep the night before and higher self-reported energy the previous day were both associated with improved next-day well-being, which is less surprising.
The researchers are careful about what they think the variability finding does and does not mean. They are not arguing that swinging blood sugar levels are beneficial. Their interpretation is that people who work especially hard to eliminate normal fluctuations may impose restrictions on themselves that make everyday life less enjoyable or make certain activities feel harder to pursue safely.
In their own words: ‘Days with higher time in the normal safe range for blood sugar were followed by days on which individuals 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 improved next-day quality of life. These findings may suggest that individuals experience lower quality of life when attempting 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 safely engage in certain activities.’
What to make of a conference abstract
A few caveats apply before this finding travels too far. The research has not yet been published in a peer-reviewed journal, it will be presented at EASD in Milan, which means the full methodology and statistical detail have not yet been subjected to formal peer review. The sample is observational, the follow-up period is 14 days, and the causal direction of the variability association is not established by the study design. The researchers used modelling to reduce confounding, but self-reported well-being measures carry their own limitations.
What the study does offer is a pointed question for clinicians and patients: whether the pursuit of extremely tight glucose control, in some individuals, carries a lifestyle cost that current treatment frameworks do not adequately capture. The full presentation at the EASD meeting in Milan will be the next opportunity to examine the methodology in greater detail.
