Background: Little is known about the effects of dietary quality on the risk of ischemic stroke among Southwest Chinese, and evidence from prospective studies is needed. We aimed to evaluate the associations of ischemic stroke with dietary quality assessed by the Chinese Diet Balance Index 2016 (DBI-2016). Methods: The Guizhou Population Health Cohort Study (GPHCS) recruited 9280 residents aged 18 to 95 years from 12 areas in Guizhou Province, Southwest China. Baseline investigations, including information collections of diet and demographic characteristics, and anthropometric measurements were performed from 2010 to 2012. Dietary quality was assessed by using DBI-2016. The primary outcome was incident ischemic stroke diagnosed according to the International Classification of Diseases 10th revision (ICD-10) until December 2020. Data analyzed in the current study was from 7841 participants with complete information of diet assessments and ischemic stroke certification. Cox proportional hazards models were used to estimate the risk of ischemic stroke associated with dietary quality. Results: During a median follow-up of 6.63 years (range 1.11 to 9.53 years), 142 participants were diagnosed with ischemic stroke. Participants with ischemic stroke had a more excessive intake of cooking oils, alcoholic beverages, and salt, and had more inadequacy in meats than those without ischemic stroke. (p < 0.05). Compared with participants in the lowest quartile (Q1), those in the highest quartile (Q4) of the higher bound score (HBS) and of the dietary quality distance (DQD) had an elevated risk for ischemic stroke, with the corresponding hazard ratios (HRs) of 3.31 (95%CI: 1.57–6.97) and 2.26 (95%CI: 1.28–4.00), respectively, after adjustment for age, ethnic group, education level, marriage status, smoking and waist circumference, and the medical history of diabetes and hypertension at baseline. In addition, excessive intake levels (score 1–6) of cooking oils, excessive intake levels (score 1–6) of salt, and inadequate intake levels (score −12 to −7) of dietary variety were positively associated with an increased risk for ischemic stroke, with the multiple HRs of 3.00 (95%CI: 1.77–5.07), 2.03 (95%CI: 1.33–3.10) and 5.40 (95%CI: 1.70–17.20), respectively. Conclusions: Our results suggest that unfavorable dietary quality, including overall excessive consumption, excessive intake of cooking oils and salt, or under adequate dietary diversity, may increase the risk for ischemic stroke.

Real-world metal exposure is usually mixed, and single-metal analyses cannot reflect actual health risks. This study used multiple statistical approaches to investigate the effects of mixed-metal exposure on incident hypertension and identify key metals and exposure patterns. A total of 3749 participants were enrolled from the Guizhou Population Health Cohort Study. Cox proportional hazards model, factor analysis, weighted quantile sum regression (WQS), quantile g-computation (qgcomp), and Bayesian kernel machine regression (BKMR) were employed. During a median follow-up of 6.63 years, 806 incident hypertension cases were identified. After multivariable adjustment, Fe, Zn, Mg, and K were associated with decreased hypertension risk, while As, Mn, and Na were associated with increased risk (P < 0.050). Factor analysis identified three factors: Factor 1 (eight essential metals), Factor 2 (Mn alone), and Factor 3 (Sr‑As). Factor 1 was inversely associated with hypertension (HR=0.920, 95%CI:0.855‑0.990), whereas Factor 2 was positively associated (HR=1.205, 95%CI:1.120‑1.297). In WQS, each 1‑percentile increase in Factor 1 index corresponded to an 11.8% risk reduction (RR=0.882, 95%CI:0.788‑0.988), with K as the main contributor. In qgcomp, each 1‑quantile increase in Factor 1 mixture reduced risk by 10.9% (RR=0.891, 95%CI:0.795‑0.999), with Na and Se driving positive effects, and K, Fe, Mg driving negative effects. BKMR revealed an overall low‑dose beneficial and high‑dose harmful pattern, with Mn as the dominant contributor (PIP=0.807). Metal mixtures showed correlated exposure patterns and non‑linear relationships with hypertension. Hypertension prevention should ensure sufficient essential metals and control exposure to hazardous metals including Mn and Na.