Association between Plasma Homocysteine Concentrations and the First Ischemic Stroke in Hypertensive Patients with Obstructive Sleep Apnea: A 7-Year Retrospective Cohort Study from China

Association between elevated homocysteine levels and obstructive sleep apnea hypopnea syndrome: a systematic review and updated meta-analysis

Objective

This study aimed to distinguish between healthy controls and patients with OSAHS regarding homocysteine (HCY) levels and investigate how individuals with OSAHS respond to continuous positive airway pressure ventilation (CPAP) in terms of serum and plasma HCY levels.

Methods

To ascertain published articles about OSAHS, an exhaustive search was performed across medical databases, encompassing PubMed, Web of Science, EMBASE, CNKI, and Cochrane Library, until January 2, 2024. This study reviewed the literature regarding HCY levels in individuals with OSAHS and control groups, HCY levels under pre- and post-CPAP treatment, the Pearson/Spearman correlation coefficients between HCY levels and apnea-hypopnea index (AHI), and the hazard ratio (HR) of HCY levels concerning the occurrence of major adverse cerebrocardiovascular events (MACCEs) in patients with OSAHS. Meta-analyses were performed using weighted mean difference (WMD), correlation coefficients, and HR as effect variables. The statistical analysis was conducted using the R 4.1.2 and STATA 11.0 software packages.

Results

In total, 33 articles were selected for the final analysis. The OSAHS group exhibited significantly higher serum/plasma HCY levels than the control group (WMD = 4.25 μmol/L, 95% CI: 2.60-5.91, P< 0.001), particularly among individuals with moderate and severe OSAHS. Additionally, subgroup analysis using mean age, ethnicity, mean body mass index, and study design type unveiled significantly elevated levels of HCY in the serum/plasma of the OSAHS group compared to the control group. CPAP treatment can significantly decrease serum/plasma HCY levels in patients with OSAHS. Moreover, elevated HCY levels in individuals with OSAHS could be one of the risk factors for MACCEs (adjusted HR = 1.68, 95% CI = 1.10-2.58, P = 0.017). AHI scores show a positive correlation with serum/plasma HCY levels.

Conclusion

Patients with OSAHS had elevated serum/plasma HCY levels compared to healthy controls; however, CPAP therapy dramatically decreased HCY levels in patients with OSAHS. In patients with OSAHS, elevated HCY levels were linked with an increased risk of MACCEs, and HCY was positively connected with AHI values. HCY levels may serve as a useful clinical indicator for determining the severity and efficacy of OSAHS treatments.

Systematic review registration

https://www.crd.york.ac.uk/prospero/, identifier CRD42024498806.

Obstructive sleep apnea affects cognition: dual effects of intermittent hypoxia on neurons

Obstructive sleep apnea (OSA) is a common respiratory disorder. Multiple organs, especially the central nervous system (CNS), are damaged, and dysfunctional when intermittent hypoxia (IH) occurs during sleep for a long time. The quality of life of individuals with OSA is significantly impacted by cognitive decline, which also escalates the financial strain on their families. Consequently, the development of novel therapies becomes imperative. IH induces oxidative stress, endoplasmic reticulum stress, iron deposition, and neuroinflammation in neurons. Synaptic dysfunction, reactive gliosis, apoptosis, neuroinflammation, and inhibition of neurogenesis can lead to learning and long-term memory impairment. In addition to nerve injury, the role of IH in neuroprotection was also explored. While causing neuron damage, IH activates the neuronal self-repairing mechanism by regulating antioxidant capacity and preventing toxic protein deposition. By stimulating the proliferation and differentiation of neural stem cells (NSCs), IH has the potential to enhance the ratio of neonatal neurons and counteract the decline in neuron numbers. This review emphasizes the perspectives and opportunities for the neuroprotective effects of IH and informs novel insights and therapeutic strategies in OSA.

Association between plasma total homocysteine (tHcy) and strokes: A meta-analysis

Objective

Inconsistent findings have been reported regarding the association between elevated plasma total homocysteine (tHcy) and the risk of different types of strokes. We conducted this meta-analysis to identify the association between tHcy and different kinds of strokes or recurrences of strokes, and provide evidence for preventing.

Methods

Relevant studies published before May 1, 2022 in databases such as PubMed, EMBASE, the Cochrane Library, CNKI, and Wanfang were retrieved. Two researchers independently searched and extracted the data, and used Stata 16.0 statistical software for analysis. Results were presented as the odds risk (OR) and the corresponding 95% confidence intervals (CI).

Results

In total, 24 articles were included, involving 51,426 subjects, of which 4,983 had stroke events during follow-up. Relative to lower tHcy, higher tHcy were associated with increased stroke (OR = 1.95, 95% CI: 1.59–2.37), ischemic stroke (OR = 1.71, 95% CI: 1.39–2.11), hemorrhagic stroke (OR = 1.99, 95% CI: 1.03–3.84), and recurrent stroke (OR = 1.25, 95% CI: 1.12–1.39), respectively.

Conclusions

This study shows that elevated tHcy increases the risk of stroke, including ischemic stroke and hemorrhagic stroke, and is closely related to the recurrence of stroke. It is recommended to pay attention to the detection of tHcy in the management of stroke patients in the future, and take effective measures to prevent and delay the progression of stroke.

Associations of the Cardiometabolic Index with the Risk of Cardiovascular Disease in Patients with Hypertension and Obstructive Sleep Apnea: Results of a Longitudinal Cohort Study

Purpose

We aimed to explore the relationship between the cardiometabolic index (CMI) and cardiovascular disease (CVD) and its subtypes (coronary artery disease and stroke) in patients with hypertension and obstructive sleep apnea (OSA).

Methods

We conducted a retrospective cohort study enrolling 2067 participants from the Urumqi Research on Sleep Apnea and Hypertension study. The CMI was calculated as triglyceride to high‐density lipoprotein cholesterol ratio × waist‐to‐height ratio. Participants were divided into three groups (T1, T2, and T3) according to the tertile of CMI. The Kaplan-Meier method helped to calculate the cumulative incidence of CVD in different groups. We assessed the association of CMI with the risk of CVD and CVD subtypes by estimating hazard ratios (HRs) and 95% confidence intervals (CIs) using Cox models.

Results

During a median follow-up of 6.83 years (interquartile range: 5.92-8.00 years), 326 incident CVD were identified, including 121 incident stroke and 205 incident coronary heart disease (CHD). Overall, after adjusting for confounding variables, CMI was positively associated with the risk of new-onset CVD (per SD increment, adjusted HR: 1.31; 95% CI: 1.20, 1.43), new-onset CHD (per SD increment, adjusted HR: 1.33; 95% CI: 1.20, 1.48), and new-onset stroke (per SD increment, adjusted HR: 1.27; 95% CI: 1.10, 1.47). Similar results were obtained in various subgroup and sensitivity analyses. Adding CMI to the baseline risk model for CVD improved the C-index (P < 0.001), continuous net reclassification improvement (P < 0.001), and integrated discrimination index (P < 0.001). Similar results were observed for CHD and stroke.

Conclusion

There was a positive association between CMI levels and the risk of new-onset CVD in patients with hypertension and OSA. This finding suggests that CMI may help identify people at high risk of developing CVD.

Dose-Response Associations of Metabolic Score for Insulin Resistance Index with Nonalcoholic Fatty Liver Disease among a Nonobese Chinese Population: Retrospective Evidence from a Population-Based Cohort Study

Purpose

This study is aimed at investigating the association between the metabolic score for insulin resistance (METS-IR) index and nonalcoholic fatty liver disease (NAFLD) in the nonobese population and its predictive value.

Methods

10730 nonobese subjects were selected from longitudinal cohort research conducted from January 2010 to December 2014. Cox proportional hazards models were employed to assess the relationship between METS-IR and new-onset NAFLD. Generalized additive models were used to identify nonlinear relationships. In addition, we performed subgroup analyses and interaction tests. The time-dependent receiver operating curve (ROC) and area under the ROC (AUC) were utilized to measure the discriminatory ability of METS-IR for new-onset NAFLD. Beyond clinical risk factors, the incremental predictive value of METS-IR was appraised using integrated discrimination improvement (IDI), C-index, and net reclassification index (NRI).

Results

Over a median period of 804.50 days of follow-up, 1859 (17.33%) participants had a new onset of NAFLD. After adjusting for confounders, the HR for new-onset NAFLD in the Q4 group was 6.40 compared with the Q1 group. When METS-IR was considered a continuous variable, the risk of NAFLD increased by 34% for every 1 SD increase in METS-IR. The smoothing curve shows the dose-response relationship between METS-IR and the presence of new-onset NAFLD. Using a two-piecewise linear regression model, we derived a METS-IR inflection point of 36. HRs were 1.31 on the left side of the inflection point and 1.04 on the right side of the inflection point (log-likelihood ratio test, P < 0.001). Subgroup analyses and interaction tests revealed an interaction between gender and SBP in the association between METS-IR and new-onset NAFLD. In the subgroup analysis of gender and SBP, we observed a higher risk of new-onset NAFLD in men and in those with abnormal SBP levels. We evaluated the ability of METS-IR to identify new-onset NAFLD at different time points. The AUCs at 1, 2, 3, and 4 years were 0.784, 0.756, 0.758, and 0.752, respectively, which represent good discrimination of new-onset NAFLD. The addition of METS-IR greatly improved the reclassification and differentiation of clinical risk factors, with an NRI of 0.276 and an IDI of 0.068. In addition, the addition of METS-IR increased the C-index from 0.719 to 0.771.

Conclusion

In a nonobese Chinese population, elevated METS-IR was independently associated with an enhanced risk of NAFLD development and a dose-response relationship existed. In addition, METS-IR might be a reliable indicator for screening individuals at risk for early NAFLD, especially in nonobese populations.

Nonlinear Relationship Between Chinese Visceral Adiposity Index and New-Onset Myocardial Infarction in Patients with Hypertension and Obstructive Sleep Apnoea: Insights from a Cohort Study

Purpose

We aimed to investigate the relationship between the Chinese visceral adiposity index (CVAI) and the risk of new-onset myocardial infarction (MI) in patients with hypertension and obstructive sleep apnoea (OSA) and to inspect possible modifiers of the effect.

Methods

The Cox regression model was used to evaluate the relationship between baseline CVAI and risk of new-onset MI. A generalized additive model was used to identify the nonlinear relationship. Besides, we conducted subgroup analyses and interaction tests.

Results

A total of 2177 patients with hypertension and OSA undergoing polysomnography were enrolled in this study. During a median follow-up period of 87 months, 82 participants developed new-onset MI. Overall, CVAI was positively related to the risk of new-onset MI (per 1 SD increase; HR = 1.54, 95% CI: 1.28–1.85). In multivariable-adjusted models, the risk of new-onset MI increased with quartiles of CVAI, with an HR of 3.64 (95% CI: 1.94–6.83) for quartile 4 compared with quartile 1. The generalized additive model and smoothed curve fit revealed a nonlinear relationship between CVAI and risk of new-onset MI with an inflection point of approximately 112. None of the stratification variables had a significant effect on the relationship between CVAI and new-onset MI. Similar outcomes were observed in the sensitivity analysis. The addition of CVAI significantly improved reclassification and discrimination over the conventional model, with a category-free NRI of 0.132 (95% CI 0.021 to 0.236, P = 0.021) and an IDI of 0.012 (95% CI 0.005 to 0.023, P < 0.001).

Conclusion

This study demonstrated a nonlinear relationship between CVAI and the risk of new-onset MI in patients with hypertension and OSA. Higher CVAI was significantly associated with the risk of new-onset MI when CVAI was ≥112.

The Correlations Between Serum Hcy Level and Seizures and Cognitive Function in Patients After Stroke

BACKGROUNDS

Post-stroke cognitive dysfunction (PSCI), a set of illnesses ranging from moderate cognitive impairment to dementia, which is one of the most prevalent consequences following a stroke. Homocysteine (Hcy) has been related to a number of neurological and systemic diseases. It's also a known risk factor for cardiovascular disease and systemic atherosclerosis (CVD). The link between Hcy and PSCI, on the other hand, is unknown.

METHODS

Our hospital evaluated 325 patients with acute cerebral infarction between January 1, 2018 and December 1, 2021. There are biological markers and baseline data available. Patients were divided into two groups based on the results of the Montreal Cognitive Assessment (MoCA). The researchers performed logistic regression analysis to find variables that may be linked to PSCI.

RESULTS

HCY levels were significantly higher in PSCI patients than in non-PSCI patients. Age, education, seizure manifestation, and income level were all shown to be independent risk variables for PSCI in a multivariate logistic analysis. Hcy levels in PSCI patients differed considerably between the high and low groups. The high and low Hcy levels groups had significantly varied hypertension histories and urine levels. Hcy levels in PSCI patients differed considerably between the high and low groups. The high and low Hcy levels groups had significantly varied hypertension histories and urine levels.

CONCLUSION

Serum Hcy levels have been linked to PSCI in post-stroke patients, and researchers believe that serum Hcy levels will diminish PSCI.