Is Cerebral Microembolism in Mechanical Prosthetic Heart Valves Clinically Relevant?

BACKGROUND AND PURPOSE: High-intensity transient signals (HITS) are frequently detected by transcranial Doppler (TCD) ultrasound in patients with mechanical prosthetic heart valves (PHVs), but published data about their clinical relevance are controversial. This study was undertaken to determine the clinical relevance of HITS in patients with mechanical PHVs. METHODS: The authors prospectively studied patients with mechanical PHVs using TCD monitoring for microemboli detection with and without O2 inhalation. The cognitive testing of patients included the Mini-Mental State Examination, the Dementia Rating Scale, and MicroCog. RESULTS: The authors studied 36 patients (20 women, aged 58 +/- 13 years). HITS were detected in 72% of patients, with a nonsignificant increase of HITS rate in the aortic valve group (P = .07). There was no significant difference in HITS rate between asymptomatic and symptomatic patients. In a multiple linear regression model, HITS rate was predicted only by younger age (P = .024). No correlation was found between HITS rate and the cognitive performance of patients. There was a significant decrease in HITS rate after 100% O2 inhalation compared to baseline levels (32.8 +/- 40.2 vs 6.1 +/- 11.3, P = .011). Subgroup analysis in asymptomatic patients confirmed this finding (P = .017), but in symptomatic patients, decreased HITS rate was not statistically significant (P = .18). CONCLUSION: Only age was a significant predictor of HITS in patients with mechanical PHVs. The lack of association between HITS, clinical symptoms, and cognitive functioning suggests that most of these signals represent harmless epiphenomena, and only HITS detected after O2 inhalation have any clinical relevance.     

Bundling occupational safety with harm reduction information as a feasible method for improving police receptiveness to syringe access programs: evidence from three U.S. cities

Introduction  

In light of overwhelming evidence that access to sterile injection equipment reduces incidence of injection-attributable bloodborne disease without encouraging drug use, many localities have authorized sterile syringe access programs (SAPs), including syringe exchange and pharmacy-based initiatives. Even where such interventions are clearly legal, many law enforcement officers are unaware of the public health benefits and legal status of these programs and may continue to treat the possession of injection equipment as illegal and program participation as a marker of illegal behavior. Law enforcement practice can impede SAP utilization and may increase the risk of needlestick injury (NSI) among law enforcement personnel. Many SAPs conduct little or no outreach to law enforcement, in part because they perceive law enforcement actors as unreceptive to health-promotion programs targeting drug users.     

Orthostatic-Mediated Hypoperfusion in Limb-Shaking Transient Ischemic Attack

In patients with severe carotid stenosis or total occlusion, episodic contralateral motor dysfunction is more likely related to cerebral hypoperfusion than epileptogenic activity. A man with orthostatic-mediated right-sided limb shaking was found to have total left internal carotid artery occlusion. There was prominent reduction of cerebrovascular reserve seen on single photon emission computed tomography (SPECT) performed with and without acetazolamide. During assumption of an upright position transcranial Doppler (TCD) revealed a marked attenuation of the left middle cerebral artery flow pattern not associated with changes during electroencephalographic monitoring, even after administration of acetazolamide. In this man, limb shaking episodes were attributed to hypoperfusion of the contralateral cerebral hemisphere, and not to epileptogenic activity.     

Police Encounters Among Needle Exchange Clients in Baltimore: Drug Law Enforcement as a Structural Determinant of Health

Objectives. We piloted a monitoring mechanism to document police encounters around programs targeting people who inject drugs (PWID), and assessed their demographic predictors at 2 Baltimore, Maryland, needle exchange program (NEP) sites.Methods. In a brief survey, 308 clients quantified, characterized, and sited recent police encounters. Multivariate linear regression determined encounter predictors, and we used geocoordinate maps to illustrate clusters.Results. Within the past 6 months, clients reported a median of 3 stops near NEP sites (interquartile range [IQR] = 0–7.5) and a median of 1 arrest in any location (IQR = 0–2). Three respondents reported police referral to the NEP. Being younger (P = .009), being male (P = .033), and making frequent NEP visits (P = .02) were associated with reported police stops. Among clients reporting arrest or citation for syringe possession, Whites were significantly less likely than non-Whites to report being en route to or from an NEP (P < .001). Reported encounters were clustered around NEPs.Conclusions. Systematic surveillance of structural determinants of health for PWID proved feasible when integrated into service activities. Improved monitoring is critical to informing interventions to align policing with public health, especially among groups subject to disproportionate levels of drug law enforcement.Laws and policing practices are broadly understood to act as structural determinants of health for people who inject drugs (PWID). In many US jurisdictions, laws have historically prevented over-the-counter sale and possession of syringes, reflecting a theory that legal restrictions on access to clean injection equipment can deter drug abuse.1 Other policies have banned federal, state, and municipal appropriations for needle exchange programs (NEPs), vastly underresourcing these public health initiatives and facilitating infectious disease spread among PWID and across communities.1,2 Possession of injecting equipment is generally a crime under state laws prohibiting drug paraphernalia, authorizing syringe confiscation and arrest of PWID by street-level law enforcement officers.3In the past 2 decades, an extensive evidence base demonstrating NEPs to be both efficacious in reducing the transmission of infectious disease (such as HIV and HCV) and cost-effective without increasing drug abuse3a has helped shift the US policy environment relating to syringe access. To date, 28 states have established regulation of retail sale and possession of syringes; NEPs have received official authorization in at least 18 states, sometimes only in the context of a public health emergency.3 Elsewhere, NEP clients gained formal or informal exemption from drug paraphernalia laws to encourage program use.4 These shifts have occurred in the context of other drug policy reforms that have begun the process of aligning the criminal justice regime with sound public health science.5,6There is considerable evidence, however, that policy reform is in and of itself insufficient to align police practices with public health prevention efforts in the realm of substance abuse.7–10 Wide enforcement discretion, management failures, and other gaps in the policy implementation process10 leave room for police officers to continue to confiscate legal injection equipment and interfere with the functioning of NEPs even after legal sanction.9,11,12Even under a favorable policy regime, policing practices can adversely affect the behavior and health of PWID. A number of studies from the United States and elsewhere suggest that police encounters are associated with higher odds of HIV infection, drug overdose, and other deleterious outcomes among PWID.10,13–25 Extrajudicial police practices such as unauthorized confiscation of injection equipment and physical abuse are widespread and have shown especially robust associations with risk behavior and adverse health outcomes among PWID, including HIV seroconversion.14,23,26–37 In a national survey of NEPs in the United States, 43% reported that their clients experience police harassment on at least a monthly basis.8 Aside from direct police interference with NEP program operations,10,18–21,25 experience and perceptions of police practices can deter uptake of disease prevention services by PWID.13–17,38–40 Disproportionate police presence in communities of color and racially biased policing practices likely exacerbate racial disparities in HIV acquisition and other health outcomes.13–17,38Although police interference has been sporadically documented and linked to risky injection behaviors among PWID populations, little research has attempted to evaluate mechanisms for systematically measuring the extent or prevalence of these adverse interactions. According to our previous research, only a small minority of NEPs in the United States report consistently monitoring adverse events involving police and program clients or staff.8 To our knowledge, those programs that do have a system for documenting police encounters have not formally described their methods or analyzed their findings. We piloted and evaluated a surveillance system to document levels of reported police interaction with NEP clients in an urban setting of Baltimore, Maryland. In light of the racially charged nature of drug law enforcement,41–44 our hypothesis was that non-White NEP clients would report higher levels of police encounters than White clients.