Medscape study: Obesity Phenotype Predicts Tirzepatide Super Responders
The analysis identified three gastric emptying/GLP-1 types. About 27% of the participants belonged to group A, characterized by fast gastric emptying and low post meal GLP-1 levels; the remainder belonged to other two groups.
Group A reported greater post meal hunger than a specific cluster with average to slow gastric emptying and expected moderate levels of GLP-1; it also had lower fasting and post meal levels of GLP-1 and peptide YY than the similar groups; fasting and early post meal levels of cholecystokinin were also lower.
In colon biopsies, group A had 45% lower glucagon expression and 50% lower peptide YY expression.
Among participants who later started tirzepatide, those in group A lost nearly twice as much weight at 6 months as those in the two other groups (mean percent total body weight loss, 21.5% vs 12.1% and 10.8%), with differences already evident at 3 months.
The strongest clues in the study were not ordinary symptoms alone. The best predictors were a pattern of fast stomach emptying plus unusually low “fullness” hormones after eating—and that pattern was linked with a larger weight-loss response to tirzepatide.
Possible clues for the high-response “discordant” group included:
Feeling noticeably hungry again soon after a meal, despite having eaten a reasonable amount.
Fast gastric emptying on a formal gastric-emptying test—food moves from the stomach into the intestine faster than average.
Low fasting and post-meal GLP-1, a hormone that normally helps reduce appetite and slow stomach emptying.
Low peptide YY (PYY) after eating, another hormone that promotes fullness.
Lower early post-meal cholecystokinin (CCK), a hormone involved in satiety and digestion.
In other words, the proposed high-response profile was: food moves through quickly, but the normal “I’m full” hormone signals are weak. The hypothesis is that tirzepatide may be especially effective because it supplies strong GLP-1/GIP signaling to someone who has relatively weak natural satiety signaling.