Syndrome W: A new model of hyperinsulinemia, hypertension and midlife weight gain in healthy women with normal glucose tolerance

To characterize a new insulin resistance syndrome in euglycemic midlife women and the relationship of its features (including hypertension and dyslipidemia), with hyperinsulinemia (AUC insulin ≥100 μU/mL), retrospective cohort analysis was conducted in 278 consecutive women who presented to a Menopausal Health Program. Of 67 women with midlife weight gain "greater than 20 pounds since their twenties" and body mass indices (BMIs) between 25 and 32 kg/m², none of the subjects met criteria for Type 2 diabetes, 5 women had impaired glucose tolerance, and 36 women were hyperinsulinemic. Hyperinsulinemia was a highly statistically significant determinant of hypertension, dyslipidemia, and truncal obesity (Odds Ratios 10.6, 4.0, and 13.7; P values ≤ 0.0001, ≤ 0.007, and ≤ 0.0001) in cross-tabulations. AUC insulin was the best predictor variable of hypertension and dyslipidemia in univariate and multivariate logistic regression models (univariate P values 0.0004 and 0.0088). After adjustment for BMI, age, and estrogen use, the final models, correctly classified, respectively, 74% and 69% of all cases in the dataset (model P values: ≤ 0.0001 and ≤ 0.0067) and AUC insulin had a log-linear (i.e., dose-dependent) relationship with hypertension and dyslipidemia, which suggests causality. We propose that the constellation of symptoms that includes midlife weight gain, "waist-gain," hypertension, dyslipidemia, and appetite dysregulation in euglycemic women with hyperinsulinemia be titled Syndrome W and suggest that the highly statistically significant relationship of hyperinsulinemia with the characteristic features are evidence of a causal role for insulin in its etiology. The identification of Syndrome W before the onset of overt impaired glucose tolerance, diabetes, or manifestations of coronary artery disease could have important clinical and public health implications for midlife women.