Hypertension Trends and White Matter Brain Injury in the Offspring Framingham Heart Study Cohort

BACKGROUND

Hypertension is the most potent stroke risk factor and is also related to cerebral small vessel disease. We studied the relation between mid-to-late-life hypertension trends and cerebral white matter injury in community-dwelling individuals from the FHS (Framingham Heart Study).

METHODS

FHS Offspring cohort participants with available mid-life and late-life blood pressure measurements and brain magnetic resonance imaging were included. Multiple regression analyses were used to relate hypertension trends (normotension-normotension [reference], normotension-hypertension, and hypertension-hypertension) to white matter injury metrics on diffusion tensor imaging (free water, fractional anisotropy, and peak skeletonized mean diffusivity) and Fluid Attenuated Inversion Recovery (white matter hyperintensity volume) by different blood pressure cutoffs (130/80, 140/90, and 150/90 mm Hg).

RESULTS

We included 1018 participants (mean age 47.3±7.4 years at mid-life and 73.2±7.3 at late-life). At the 140/90 mm Hg cutoff, the hypertension-hypertension trend was associated with higher free water (β, 0.16 [95% CI, 0.03-0.30]; P=0.021) and peak skeletonized mean diffusivity (β, 0.15 [95% CI, 0.01-0.29]; P=0.033). At a 130/80 mm Hg cutoff, the hypertension-hypertension trend had significantly higher free water (β, 0.16 [95% CI, 0.01-0.30]; P=0.035); and the normotension-hypertension (β, 0.24 [95% CI, 0.03-0.44]; P=0.027) and hypertension-hypertension (β, 0.22 [95% CI, 0.04-0.41]; P=0.022) trends had significantly increased white matter hyperintensity volume. Exploratory stratified analysis showed effect modifications by APOE ɛ4 allele and age.

CONCLUSIONS

Mid-to-late-life hypertension exposure is significantly associated with microstructural and to a lesser extent, visible white matter injury; the effects are observed at both conventional and lower blood pressure cutoffs and are associated with longer duration of hypertension.

Mid to Late Life Hypertension Trends and Cerebral Small Vessel Disease in the Framingham Heart Study

The duration and lifetime pattern of hypertension is related to risk of stroke and dementia. In turn, cerebral small vessel disease (CSVD) is the most frequent form of cerebrovascular disease underlying dementia and stroke. Thus, study of the relation of mid to late life hypertension trends with CSVD late in life will help understand hypertension's role and inform preventive efforts of CSVD consequences. We studied 1686 Framingham Heart Study Offspring cohort participants free of stroke and dementia, who were examined in mid and late life, and had available brain magnetic resonance imaging during late life. We related hypertension trends between mid and late life (normotension-normotension N-N, normotension-hypertension N-H, hypertension-hypertension H-H) to cerebral microbleeds and covert brain infarcts (CBI), overall and stratified by brain topography. We used multivariable logistic regression analyses to calculate odds ratio and 95% CIs for CSVD measures. The prevalence of CSVD in late life was 8% for cerebral microbleeds and 13% for covert brain infarcts and increased with longer hypertension exposure across all brain regions. Compared with the trend pattern of N-N, both N-H and H-H trends had higher odds of mixed cerebral microbleeds (2.71 [1.08-6.80], and 3.44 [1.39-8.60], respectively); H-H also had higher odds of any cerebral microbleeds or covert brain infarcts (1.54 [1.12-2.20]), and any covert brain infarcts (1.55 [1.08-2.20]). The burden of CSVD also increased with longer hypertension exposure. Our results highlight hypertension having a major role in subclinical CSVD, across subtypes and brain regions, and call attention to improve recognition and treatment of hypertension early in life.

Acute stroke, catheter related venous thrombosis, and paradoxical cerebral embolism: report of two cases

BACKGROUND

Patent foramen ovale (PFO) has been associated with cryptogenic stroke, particularly in young adults. However, the source of particles leading to cerebral embolism remains frequently unknown despite comprehensive evaluation.

OBJECTIVE

To report and comment on therapeutic options for 2 patients with acute ischemic strokes, PFO, and venous access related thrombosis, sources of paradoxical embolism, from Boston Medical Center stroke database.

CASE DESCRIPTIONS

Case 1. A 71-year-old man presented with brain magnetic resonance imaging (MRI) confirmed acute cerebellar infarction. Echocardiography showed a PFO and thrombotic material at the tip of a peripherally inserted central catheter (PICC) line in the superior vena cava (SVC) prolapsing into the right atrium (RA). Case 2. A 64-year-old woman with end-stage renal disease and PFO presented with brain MRI confirmed acute parietal lobe infarction. Three days prior to her stroke, she had thrombectomy and venoplasty of an arterio-venous (AV) dialysis graft followed by a post-thrombectomy fistulogram that showed persistent thrombotic material at the venous site.

CONCLUSIONS

PFO associated with large venous access site thrombosis was the most likely mechanism of stroke in both cases. Local thrombosis at sites of large venous access may be an overlooked source of paradoxical embolism in patients with PFO as well as a preventable cause of stroke in critically ill patients.

Eye injury in migrant farm workers and suggested hazard controls

The eyes are a common site of injury in agricultural operations. Identification of the cause of injury is important to inform preventive interventions. The objective of this study was to describe the hazards and mechanisms of acute traumatic injury to the eyes of agricultural workers who are hired in farming operations on a seasonal basis. A review of the literature was performed to summarize the mechanisms of eye injuries in agriculture. Field observations and informal interviews were performed to verify the literature and to determine whether there are eye hazards for farm workers that have not been reported in the literature. Additional mechanisms of injury were elicited, and suggested methods of injury prevention are presented here.

The theory of planned behavior: use and application in targeting agricultural safety and health interventions

Traditional farm safety programs rely mostly on iterations of knowledge-based components, typically lack local input into identification of issues and concerns, and are difficult to evaluate. Psychological models have been looked at as tools to address these problems. The Theory of Planned Behavior (ToPB) is a psychological model that has been used to understand behavioral beliefs and to provide a framework for using those beliefs as intervention targets. The fundamental characteristics of ToPB are reviewed. Examples of specifically stated behavioral questions are provided from ToPB application in field settings. Pertinent findings from an example study on personal protective equipment use and beliefs are summarized to illustrate advantages and disadvantages of using ToPB. ToPB can provide information useful in targeting interventions aimed at locally identified safety and health concerns. The use of beliefs identified using ToPB as intervention targets can increase the use of personal protective equipment beyond levels used prior to the intervention. And, ToPB has shown multiple correlations of 0.28 (up to 0.35 in other examples not reported) between intentions and self-reported behaviors, indicating that other contributory factors are present and need to be studied.