Association between benzodiazepine use and risks of chronic-onset poststroke pneumonia: a population-based cohort study

Incident Benzodiazepine and Z-Drug Use and Subsequent Risk of Serious Infections

BACKGROUND AND OBJECTIVES

Animal studies have suggested a link between benzodiazepine and related Z-drug (BZDR) use and immune dysfunction. Corresponding evidence in humans is limited and focuses mainly on pneumonia. This study aimed to assess the association of incident BZDR use with subsequent development of serious infections.

METHODS

This Swedish register-based study included a population-based demographically matched cohort, a co-twin control cohort, and an active comparator cohort. Out of 7,362,979 individuals aged below 65 years who were BZDR naïve by 2007, 713,896 BZDR recipients with incident dispensation of any BZDRs between 2007 and 2019 were 1:1 matched to 713,896 nonrecipients from the general population; 9197 BZDR recipients were compared with their 9298 unexposed co-twins/co-multiples; and 434,900 BZDR recipients were compared with 428,074 incident selective serotonin reuptake inhibitor (SSRI) recipients. The outcomes were identified by the first inpatient or specialist outpatient diagnosis of serious infections in the National Patient Register, or death from any infections recorded as the underlying cause in the Cause of Death Register. Cox proportional hazards regression models were fitted and controlled for multiple confounders, including familial confounding and confounding by indication. To study a possible dose-response association, the cumulative dosage of BZDRs dispensed during the follow-up was estimated for each BZDR recipient and modeled as a time-varying exposure with dose categories in tertiles [≤ 20 defined daily doses (DDDs), > 20 DDDs ≤ 65, and > 65 DDDs). The risk of infections was assessed in BZDR recipients within each category of the cumulative BZDR dosage compared to their demographically matched nonrecipients.

RESULTS

In the demographically matched cohort (average age at incident BZDR use 42.8 years, 56.9% female), the crude incidence rate of any serious infections in BZDR recipients and matched nonrecipients during 1-year follow-up was 4.18 [95% confidence intervals (CI) 4.13-4.23] and 1.86 (95% CI 1.83-1.89) per 100 person-years, respectively. After controlling for demographic, socioeconomic, clinical, and pharmacological confounders, BZDR use was associated with 83% relative increase in risk of any infections [hazard ratio (HR) 1.83, 95% CI 1.79-1.89]. The risk remained increased, although attenuated, in the co-twin cohort (HR 1.55, 95% CI 1.23-1.97) and active comparator cohort (HR 1.33, 95% CI 1.30-1.35). The observed risks were similar across different types of initial BZDRs and across individual BZDRs, and the risks increased with age at BZDR initiation. We also observed a dose-response association between cumulative BZDR dosage and risk of serious infections.

CONCLUSIONS

BZDR initiation was associated with increased risks of serious infections, even when considering unmeasured familial confounding and confounding by indication. The exact pathways through which BZDRs may affect immune function, however, remain unclear. Further studies are needed to explore the neurobiological mechanisms underlying the association between BZDR use and serious infections, as it can lead to safer therapeutic strategies for patients requiring BZDR.

Benzodiazepine Initiation Effect on Mortality Among Medicare Beneficiaries Post Acute Ischemic Stroke

Rationale

Despite guideline warnings, older acute ischemic stroke (AIS) survivors still receive benzodiazepines (BZD) for agitation, insomnia, and anxiety despite being linked to severe adverse effects, such as excessive somnolence and respiratory depression. Due to polypharmacy, drug metabolism, comorbidities, and complications during the sub-acute post-stroke period, older adults are more susceptible to these adverse effects. We examined the impact of receiving BZDs within 30 days post-discharge on survival among older Medicare beneficiaries after an AIS.

Methods

Using the Medicare Provider Analysis and Review (MedPAR) dataset, Traditional fee-for-service Medicare (TM) claims, and Part D Prescription Drug Event data, we analyzed a random 20% sample of TM beneficiaries aged 66 years or older who were hospitalized for AIS between July 1, 2016, and December 31, 2019. Eligible beneficiaries were enrolled in Traditional Medicare Parts A, B, and D for at least 12 months before admission. We excluded beneficiaries who were prescribed a BZD within 90 days before hospitalization, passed away during their hospital stay, left against medical advice, or were discharged to institutional post-acute care. Our primary exposure was BZD initiation within 30 days post-discharge, and the primary outcome was 90-day mortality risk differences (RD) from discharge. We followed a trial emulation process involving cloning, weighting, and censoring, plus we used inverse-probability-of-censoring weighting to address confounding.

Results

In a sample of 47,421 beneficiaries, 826 (1.74%) initiated BZD within 30 days after discharge from stroke admission or before readmission, whichever occurred first, and 6,392 (13.48%) died within 90 days. Our study sample had a median age of 79, with an inter-quartile range (IQR) of 12, 55.3% female, 82.9% White, 10.1% Black, 1.7% Hispanic, 2.2% Asian, 0.4% American Native, 1.5% Other and 1.1% Unknown. After standardization based on age, sex, race/ethnicity, length of stay in inpatient, and baseline dementia, the estimated 90-day mortality risk was 159 events per 1,000 (95% CI: 155, 166) for the BZD initiation strategy and 133 events per 1,000 (95% CI: 132, 135) for the non-initiation strategy, with an RD of 26 events per 1,000 (95% CI: 22, 33). Subgroup analyses showed RDs of 0 events per 1,000 (95% CI: -4, 11) for patients aged 66-70, 3 events per 1,000 (95% CI: -1, 13) for patients aged 71-75, 10 events per 1,000 (95% CI: 3, 23) for patients aged 76-80, 27 events per 1,000 (95% CI: 21, 46) for patients aged 81-85, and 84 events per 1,000 (95% CI: 73, 106) for patients aged 86 years or older. RDs were 34 events per 1,000 (95% CI: 26, 48) and 20 events per 1,000 (95% CI: 11, 33) for males and females, respectively. RDs were 87 events per 1,000 (95% CI: 63, 112) for patients with baseline dementia and 18 events per 1,000 (95% CI: 13, 21) for patients without baseline dementia.

Conclusion

Initiating BZDs within 30 days post-AIS discharge significantly increased the 90-day mortality risk among Medicare beneficiaries aged 76 and older and for those with baseline dementia. These findings underscore the heightened vulnerability of older adults, especially those with cognitive impairment, to the adverse effects of BZDs.

Chinese herbal medicine and acupuncture for insomnia in stroke patients: A systematic review and meta-analysis of randomised controlled trials

BACKGROUND

Insomnia is highly prevalent in stroke patients; however, there is no ideal intervention. This systematic review examined the effect and safety of Chinese herbal medicine (CHM) and acupuncture on sleep in adults with stroke.

METHODS

Six databases were searched from inception to June 2023 to identify randomised controlled trials (RCTs). The primary outcome was Pittsburgh Sleep Quality Index (PSQI) scores. Risk of bias and evidence quality was assessed. A pairwise random-effect meta-analysis was performed.

RESULTS

A total of 54 RCTs published in 55 articles were finally included in the systematic review, including 35 of CHM and 19 of acupuncture therapies. Compared with placebo/sham procedure, CHM and acupuncture were more effective in improving PSQI scores. The evidence of moderate quality suggested that CHM outperformed benzodiazepine drugs (BZDs) while it presented an effect similar to that of non-BZDs in improving sleep quality. CHM and acupuncture also provided additional benefits to the patients treated with pharmacological agents alone. However, the evidence specific to individual CHM prescriptions lay in various factors and methodological quality, and the evidence on the comparative effectiveness between acupuncture and other therapies was conflicting or limited.

CONCLUSIONS

Overall, CHM and acupuncture used alone or in combination with pharmacotherapy can safely improve sleep in stroke patients with insomnia. In the future, RCTs on outstanding CHM prescriptions and the comparative effectiveness research between acupuncture and other therapies are needed.

REGISTRATION

PROSPERO No. CRD42020194029 and No. CRD42020194030.

Effect of alteplase, benzodiazepines and beta-blocker on post-stroke pneumonia: Exploration of VISTA-Acute

BACKGROUND

Post-stroke pneumonia is a frequent complication of stroke and is associated with high mortality. Investigators have described its associations with beta-blocker. However, there has been no evaluation of the role of recombinant tissue plasminogen activator (RTPA). We postulate that RTPA may modify the effect of stroke on pneumonia by reducing stroke disability. We explore this using data from neuroprotection trials in Virtual International Stroke Trials Archive (VISTA)-Acute.

METHOD

We evaluated the impact of RTPA and other medications in random forest model. Random forest is a type of supervised ensemble tree-based machine learning method. We used the standard approach for performing random forest and partitioned the data into training (70%) and validation (30%) sets. This action enabled to the model developed on training data to be evaluated in the validation data. We borrowed idea from Coalition Game Theory on fair distribution of marginal profit (Shapley value) to determine proportional contribution of a covariate to the model. Consistent with other analysis using the VISTA-Acute data, the diagnosis of post-stroke pneumonia was based on reports of serious adverse events.

RESULTS

The overall frequency of pneumonia was 10.9% (614/5652). It was present in 11.5% of the RTPA (270/2358) and 10.4% (344/3295) of the no RTPA groups. There was significant (p<0.05) imbalance in covariates (age, baseline National Institutes of Health Stroke Scale (NIHSS), diabetes, and sex). The AUC for training data was 0.70 (95% CI 0.65-0.76), validation data was 0.67 (95% CI 0.62-0.73). The Shapley value shows that baseline NIHSS (≥10) and age (≥80) made the largest contribution to the model of pneumonia while absence of benzodiazepine may protect against pneumonia. RTPA and beta-blocker had very low effect on frequency of pneumonia.

CONCLUSION

In this cohort pneumonia was strongly associated with stroke severity and age whereas RTPA had a much lower effect. An intriguing finding is a possible association between benzodiazepine and pneumonia but this requires further evaluation.

Prevalence of oropharyngeal dysphagia in geriatric patients and real-life associations with diseases and drugs

Risk factors for oropharyngeal dysphagia (OD) in elderly patients are mainly central nervous system (CNS) and structural organic diseases or presbyphagia. We analysed the OD prevalence and association of OD with multimorbidity and polypharmacy using real-life data to complete this spectrum, with a focus on further and iatrogenic risk. This was a cross-sectional retrospective study based on a random sample of 200 patients admitted to a geriatric hospital. Data analysis included diagnoses, the detailed list of drugs, and an intense clinical investigation of swallowing according to Stanschus to screen for OD in each patient. The mean patient age was 84 ± 6.5 years. The prevalence of OD was 29.0%, without an effect of age, but a higher rate was found in men and in nursing home residents and an elevated risk of pneumonia. OD risk was slight in diabetes mellitus and COPD, and pronounced in CNS diseases. A relevant OD association was found, even after adjusting for CNS diseases, with antipsychotics, benzodiazepines, anti-Parkinson drugs, antidepressants, and antiepileptics. Further risk of OD was found with beta-blockers, alpha-blockers, opioids, antiemetics, antivertiginosa or antihistamines, metoclopramide, domperidone, anticholinergics, loop diuretics, urologics, and ophthalmics. From real-life data in patients with and without CNS diseases, we identified drug groups associated with a risk of aggravating/inducing OD. Restrictive indications for these drugs may be a preventative contribution, requiring implementation in dysphagia guidelines and an integrative dysphagia risk scale that considers all associated and cumulative medication risks in addition to diseases.

Stroke and Pneumonia: Mechanisms, Risk Factors, Management, and Prevention

A stroke is a cerebrovascular medical emergency characterized by the sudden loss of neurological function due to interruption to the blood supply. A serious and common complication of stroke is pneumonia. This review article outlined various studies in order to understand the pathogenesis pathways that lead to the development of stroke-associated pneumonia, as well as therapeutic and preventive options to reduce pneumonia. The article looked for risk factors that increase the risk of developing pneumonia among stroke patients. In addition, it has reviewed various therapeutic modalities, such as postural modifications, pharmacological treatment, and other unique treatments, in an attempt to find which of them are efficient to decrease the occurrence of pneumonia and which of them are not. The article also attempts to emphasize the importance of early screening for dysphagia among stroke patients and demonstrates the importance of preventive strategies that can be easily implemented, such as routine oral care and behavioral modifications.

Ischemic stroke and infection: A brief update on mechanisms and potential therapies

Ischemic stroke triggers a multifaceted inflammatory response in the brain that contributes to secondary brain injury and infarct expansion. In parallel with brain inflammation, ischemic stroke also leads to post-stroke immunosuppression. Stroke-induced leukopenia then predisposes patients to opportunistic infections potentially leading to pneumonia or unrinary tract infections and a worsened stroke outcome. There is evidence that the hypothalamic-pituitaryadrenal axis plays an important role in the etiology of post-stroke immunosuppression, by which prolonged glucocorticoid signalling leads to changes in immune responses. While opportunistic microbes in hospitals have been thought to be the source of infection, recent studies have reported that gut flora may also be a cause of post-stroke infection as a consequence of compromised integrity of the gut barrier after stroke. While antimicrobial drugs would appear to be a rational form of treatment for bacterial infections in stroke patients, the rise in drug-resistant bacteria and possible adverse effects of disrupting beneficial gut flora represent major challenges with these drugs. Considering the prominent role of gut microbiota in modulating immune responses, protecting and restoring the post-stroke gut bacteriome may provide significant benefit in the context of post-stroke infection. With such broad aspects of post-stroke infection occurring together with an extensive inflammatory response in the brain, a carefully considered administration of therapies for ischemic stroke is warranted.

Could prokinetic agents protect long-term nasogastric tube-dependent patients from being hospitalized for pneumonia? A nationwide population-based case-crossover study

Background

Some studies have indicated that the use of prokinetic agents may reduce pneumonia risk in some populations. Nasogastric tube insertion is known to increase the risk of pneumonia because it disrupts lower esophageal sphincter function. The aim of this study was to evaluate whether prokinetic agents could protect long-term nasogastric tube-dependent patients in Taiwan from being hospitalized for pneumonia.

Methods

A case-crossover study design was applied in this study. Long-term nasogastric tube-dependent patients who had a first-time admission to a hospital due to pneumonia from 1996 to 2013 that was recorded in the Taiwan National Health Insurance Research Database were included. The case period was set to be 30 days before admission, and two control periods were selected for analysis. Prokinetic agent use during those three periods was then assessed for the included patients. Conditional logistic regression was used to calculate the odds ratio (OR) for pneumonia admission with the use of prokinetic agents.

Results

A total of 639 first-time hospitalizations for pneumonia among patients with long-term nasogastric tube dependence were included. After adjusting the confounding factors for pneumonia, no negative association between prokinetic agent use and pneumonia hospitalization was found, and the adjusted OR was 1.342 (95% CI 0.967–1.86). In subgroup analysis, the adjusted ORs were 1.401 (0.982–1.997), 1.256 (0.87–1.814), 0.937 (0.607–1.447) and 2.222 (1.196–4.129) for elderly, stroke, diabetic and parkinsonism patients, respectively.

Conclusion

Prokinetic agent use had no negative association with pneumonia admission among long-term nasogastric tube-dependent patients in Taiwan.