Association of Metabolic Score for Insulin Resistance With Resistant Hypertension and Hypertension in Obstructive Sleep Apnea.

introductionObstructive sleep apnea (OSA) is common in the presence of hypertension and refractory hypertension (RH); however, the pathophysiological interrelationship of such conditions is yet to be well explained with insulin resistance (IR) as a key mediator. The objective of the present investigation was (1) to evaluate the association of the metabolic score of insulin resistance (METS-IR) with hypertension and RH in patients with OSA and (2) to understand whether this association varies according to the severity of OSA.

methodsIt is a retrospective cohort, which included 680 adults with OSA diagnosis in 2020-2022. The participants were stratified into quartiles in accordance with their METS-IR. Polysomnographic evaluation and metabolic profiling including body mass index (BMI), fasting blood glucose, triglycerides, and high-density lipoprotein cholesterol (HDL-C) were conducted. Multivariate logistic regression analyses were used to determine the relationship between METS-IR and hypertension/RH, adjusting for sex, lifestyle, and variables related to OSA. Subgroup analyses were also done to compare associations between severe and non-severe cases of OSA cohorts. Additionally, receiver operating characteristic (ROC) curve analysis was employed to compare the discriminative performance of METS-IR, body mass index (BMI), and the triglyceride-to-high-density lipoprotein cholesterol (TG/HDL) ratio for both hypertension and RH. Post hoc power analyses were conducted across all groups (the total cohort, the severe OSA subgroup, and the non-severe OSA subgroup) to evaluate whether the analyses were adequately powered (> 80%) to detect the observed effect sizes.

resultsElevated METS-IR levels were significantly associated with a higher prevalence of hypertension and RH. In patients with severe OSA, multivariate analysis revealed a robust, linear dose-response relationship between METS-IR and the risks of both hypertension and RH (p-trend < 0.01); conversely, in the non-severe OSA group, these associations were attenuated and did not exhibit a significant linear trend after full adjustment. ROC analysis revealed that METS-IR achieved the highest discriminative accuracy for both outcomes. For hypertension, the AUC of METS-IR (0.745) was significantly higher than that of BMI (0.729) and TG/HDL (0.636) (all p < 0.05). Similarly, for RH, METS-IR demonstrated superior discriminative ability (0.754) compared to BMI (0.746) and TG/HDL (0.610).

conclusionsMETS-IR is significantly associated with hypertension and RH in patients with severe OSA, independent of BMI, although this association is attenuated in patients with non-severe OSA. These adequately powered results support the potential utility of METS-IR as a simple metabolic marker to identify high-risk phenotypes in clinical practice to manage severe OSA. Furthermore, METS-IR is a more robust marker of hypertension and RH than BMI or TG/HDL alone, suggesting that the integration of adiposity and metabolic parameters provides superior risk stratification in OSA patients.