Can complications be prevented?

This question needs an honest answer. A complication isn’t fate; it’s a curve whose slope isn’t clear from the start. How steep it turns doesn’t hang on one thing; but heading the list is the course blood glucose takes over the years. The evidence for this comes not from one study but two independent long follow-ups.

The big type 1 diabetes trial split participants into two arms and followed them for years past its end. Once it closed, the arms’ averages converged; on paper the gap melted. Outcomes were expected to even out too. The opposite happened: the gap on the eye, kidney and nerve side didn’t close; it widened a while longer (Lachin et al., 2021).

Type 2 diabetes showed something similar too. After tight monitoring ended, the glucose gap between groups vanished within the very first year; the small-vessel advantage, in contrast, held ten years. The gap on heart attack and death, meanwhile, grew clearer as follow-up lengthened. The literature calls this picture the legacy effect.

The curve has one more feature. Nothing is felt while it builds: eye, kidney and nerves stay quiet early on. This quiet is measured in years, not days; pain doesn’t show where the curve stands, regular measurements and exams do. The screening article covers which exams make this silent stretch visible.

So how does the body remember this? Two explanations stand out. First: in long-lived tissue (vessel-wall collagen, the eye’s and kidney’s fine structures), glucose binds permanently to proteins; the bonds stay in place for years. Second: marks forming in how the cell reads its genes, marks that aren’t erased for a long time.

The hope here shouldn’t be overstated: the effect itself isn’t endless; it fades after a window of about ten years, leaving the banked gain. The same mechanism runs in reverse too: a stretch spent high leaves its own mark. That mark is quiet as well; no pain, it shows in a record spread over years. Better read this not as blame but as a measure of what putting it off costs.

A tree planted early in the garden tells this picture well. Its shade doesn’t show that day; it appears years later. A tree planted later gives shade too; it just doesn’t bring back the summers between. The real difference in front of the house isn’t planting day but unbroken care.

So the question doesn’t close with yes or no. Not every complication is stopped in every case; delay and easing, though, are a measured result. What’s more, the years gained aren’t taken back later.