Identifying hyperinsulinaemia in the absence of impaired glucose tolerance: An examination of the Kraft database.
Level 4 - case-series / case-control
Retrospective cross-sectional analysis of historical laboratory registry data
PubMed 27344544 · doi:10.1016/j.diabres.2016.06.007
What was done
Retrospective cross-sectional analysis of oral glucose tolerance tests with concurrent insulin assays performed between the 1970s and 1990s from the Kraft database. Participants were categorized by glucose tolerance status and dynamic insulin response patterns. Differences in plasma glucose, plasma insulin, demographics, and metabolic risk factors were evaluated using analysis of variance.
What was found
Participants with normal glucose tolerance accounted for 54% (n=4,185) of the cohort. Of these, 49.7% (n=2,079) displayed hyperinsulinaemia despite normal glucose clearance. Obesity showed a modest association with hyperinsulinaemia in normal glucose tolerance subjects. Fasting insulin had limited diagnostic value for hyperinsulinaemia. Among participants with impaired glucose tolerance or diabetes, 93% had concurrent hyperinsulinaemia.
Why it matters
Dynamic post-load hyperinsulinaemia occurs in approximately half of individuals with normal glucose tolerance, suggesting that metabolic dysfunction may be missed if screening relies on glucose measures or fasting insulin alone.
Limits
The study is a retrospective cross-sectional analysis of historical clinical data (1970s–1990s), introducing potential selection bias. No longitudinal outcomes or clinical endpoint follow-ups were evaluated, and the abstract omits exact effect estimates and confidence intervals.
Cited by
- supports Glucose challenge testing without measuring an insulin response misses approximately 20% of metabolic disease cases.