The combined effects of cardiometabolic index and high-sensitivity C-reactive protein on the risk of new onset stroke in a Chinese national prospective longitudinal cohort study

Abstract

Background: The Cardiometabolic Index (CMI) represents a novel anthropometric measurement, which combines characteristics of adiposity and lipids. Since obesity, lipid metabolism, and inflammation may collectively facilitate the occurrence of stroke, we hypothesize that a combination of elevated levels of the CMI and high-sensitivity C-reactive protein (hs-CRP) increases the risk of future stroke among middle-aged and older Chinese adults.

Methods: This study included 8,973 participants aged 45 years or older from the China Longitudinal Study on Health and Retirement (CHARLS), who were stroke-free and underwent baseline evaluations between 2011 and 2012, with followed-up at 2013, 2015 and 2018. The exposures were CMI and hs-CRP, with CMI calculated using the formula [waist circumference (cm)/height (cm)] × [triglycerides (mmol/L)/HDL-C (mmol/L)]. The primary outcome was the occurrence of new-onset stroke events. Cox proportional hazards models and restricted cubic spline (RCS) analyses were conducted to examine the associations between CMI, hs-CRP, and their combined effects on stroke risk. Sensitivity analysis was further implemented to verify the robustness of the results.

Results: A total of 629 participants (7.01%) suffered new-onset stroke during follow-up. The risk for stroke increased with each elevating quartile of baseline CMI levels, with adjusted HRs and 95% CIs being 1.27 (0.98-1.66), 1.41 (1.08-1.83), and 1.46 (1.09-1.96) for Q2, Q3, and Q4, respectively. Moreover, participants with levels of hs-CRP ≥ 2 mg/L also had significantly higher stroke incidence compared to those with CRP levels < 2 mg/L (adjusted HR 1.24, 95% CI 1.05-1.47, p = 0.012). Specifically, those concurrently with the highest CMI quartile and levels of hs-CRP ≥ 2 mg/L had the highest risk of stroke (adjusted HR 1.90, 95% CI 1.32-2.74). The subsequent sensitivity analyses yielded consistent results, further corroborating the initial findings.

Conclusions: The combination of CMI and hs-CRP exhibited a significant association with stroke risk among middle-aged and older Chinese adults, highlighting the importance of joint assessments of these biomarkers for refining risk stratification and enhancing primary prevention strategies for stroke.

Keywords: CHARLS; Cardiometabolic index; Stroke; hs-CRP.

Fig. 1

Flowchart illustrating participant selection in the present study

Fig. 2

Incidence density of stroke per person-year by joint of CMI and hs-CRP

Fig. 3

Joint association of CMI and hs-CRP with risk of stroke. *Model adjusted for age, sex, residence, marital status, educational level, smoking status, and drinking status body mass index, diabetes, hypertension, dyslipidemia, chronic kidney disease, cancer, heart disease, lung disease, depressive symptoms, and fasting status