Vegetarian Diets, Ayurveda, and the Case for an Integrative Nutrition Science.

Two recent studies of the health effects of vegetarian diets reported conflicting results: the EPIC-Oxford study reported a significant increase in strokes among vegetarians compared to meat-eaters among a predominantly Caucasian cohort, while another, performed on Taiwanese Buddhists, reported significantly lower incidence of strokes among vegetarians. This was doubly puzzling given the pronounced decrease in cardiovascular events among the EPIC-Oxford group. In this article, we make a detailed comparison of the actual dietary intake of various food groups by the cohorts in these studies. We then use the nutritional principles of Ayurveda-traditional Indian medicine-to show how these apparently contradictory results may be explained. Systems of traditional medicine such as Ayurveda possess profound knowledge of the effects of food on physiology. Ayurveda takes into account not just the type of food, but also multiple other factors such as taste, temperature, and time of consumption. Traditional cuisines have evolved hand in hand with such systems of medicine to optimize nutrition in the context of local climate and food availability. Harnessing the experiential wisdom of these traditional systems to create an integrative nutrition science would help fight the ongoing epidemic of chronic lifestyle diseases, and improve health and wellness.

Evaluating the utility of fasting lipid panel in addition to random lipid panel in determining lipid-lowering therapy in acute ischemic stroke or TIA patients.

BACKGROUND: Hyperlipidemia is one of the major risk factors for cerebrovascular disease and it is common practice to obtain fasting lipid profile prior to starting lipid lowering therapy (LLT). Recent AHA Guidelines published in 2018 allow for a non-fasting value to be used. OBJECTIVE: To determine if obtaining fasting lipid levels in addition to random lipid levels prompts changes in hyperlipidemia management of acute stroke patients. METHODS: 206 patients met the study criteria which included a diagnosis of acute ischemic stroke or transient ischemic attack on admission and availability of both random and fasting LDL levels collected within 72 h of each other. Patients were divided into three groups based on random LDL at admission: Group A: LDL < 70, Group B: LDL 70-99, and Group C: LDL ≥ 100 mg/dL. The dataset was analyzed to conform to the 2018 AHA/ACC guidelines using an LDL cutoff of 70 mg/dL. RESULTS: In 206 patients, statin management would change based on the fasting LDL level in 12 patients, 11 of whom were in Group B. Our data suggests that lipid management is more likely to change if the initial random LDL falls between 70-99 mg/dL as compared to a value outside of this range (P < 0.001). We present a decision algorithm to guide lipid management in acute stroke patients. CONCLUSIONS: Foregoing a fasting lipid panel to guide LLT in patients with ischemic stroke is appropriate in most cases but for select patients with random LDL levels between 70 and 99, fasting lipid profile should be obtained prior to deciding upon LLT.

Ayurvedic Treatment of Acute Ischemic Stroke: A Prospective Observational Study.

BACKGROUND: The western medical arsenal for treating stroke is rather limited, and the only treatments shown to improve outcomes are not accessible to most in the third world. Even in the developed world, many patients present too late to receive thrombolysis or thrombectomy. Stroke patients in India commonly use Ayurvedic therapies, but there are no published data regarding the efficacy or safety of these therapies, the latter being of particular concern in acute ischemic stroke (AIS). OBJECTIVE: To obtain preliminary data on the safety and efficacy of stand-alone whole-system Ayurvedic treatment in AIS. METHODS: We present here an observational study prospectively comparing outcomes in 2 cohorts of AIS patients treated with whole-system classical Ayurveda (n = 13) or conservative (nonthrombolytic, noninterventional) western biomedicine (n = 20). RESULTS: Pooled analysis of outcomes did not show statistically significant differences in mortality (15.38% vs 15%, P = 1.00), nonfatal adverse event rates (15.38% vs 30%, P = .4), or functional disability measures. A paired analysis performed using a matching algorithm to reduce baseline disparities between the cohorts also showed no statistically significant differences in outcomes. CONCLUSIONS: The safety profiles of classical Ayurveda and conservative western biomedicine in AIS are similar. This is the first ever report of stand-alone Ayurvedic therapy in AIS. Our results support the conduct of a randomized controlled trial to study the efficacy of Ayurvedic treatment of AIS.

Apparent diffusion coefficient threshold for delineation of ischemic core.

BACKGROUND: MRI-based selection of patients for acute stroke interventions requires rapid accurate estimation of the infarct core on diffusion-weighted MRI. Typically used manual methods to delineate restricted diffusion lesions are subjective and time consuming. These limitations would be overcome by a fully automated method that can rapidly and objectively delineate the ischemic core. An automated method would require predefined criteria to identify the ischemic core. AIM: The aim of this study is to determine apparent diffusion coefficient-based criteria that can be implemented in a fully automated software solution for identification of the ischemic core. METHODS: Imaging data from patients enrolled in the Diffusion and Perfusion Imaging Evaluation for Understanding Stroke Evolution (DEFUSE) study who had early revascularization following intravenous thrombolysis were included. The patients' baseline restricted diffusion and 30-day T2 -weighted fluid-attenuated inversion recovery lesions were manually delineated after coregistration. Parts of the restricted diffusion lesion that corresponded with 30-day infarct were considered ischemic core, whereas parts that corresponded with normal brain parenchyma at 30 days were considered noncore. The optimal apparent diffusion coefficient threshold to discriminate core from noncore voxels was determined by voxel-based receiver operating characteristics analysis using the Youden index. RESULTS: 51,045 diffusion positive voxels from 14 patients who met eligibility criteria were analyzed. The mean DWI lesion volume was 24 (± 23) ml. Of this, 18 (± 22) ml was ischemic core and 3 (± 5) ml was noncore. The remainder corresponded to preexisting gliosis, cerebrospinal fluid, or was lost to postinfarct atrophy. The apparent diffusion coefficient of core was lower than that of noncore voxels (P < 0.0001). The optimal threshold for identification of ischemic core was an apparent diffusion coefficient ≤ 620 × 10(-6) mm(2) /s (sensitivity 69% and specificity 78%). CONCLUSIONS: Our data suggest that the ischemic core can be identified with an absolute apparent diffusion coefficient threshold. This threshold can be implemented in image analysis software for fully automated segmentation of the ischemic core.

The infarct core is well represented by the acute diffusion lesion: sustained reversal is infrequent.

Diffusion-weighted imaging (DWI) is commonly used to assess irreversibly infarcted tissue but its accuracy is challenged by reports of diffusion lesion reversal (DLR). We investigated the frequency and implications for mismatch classification of DLR using imaging from the EPITHET (Echoplanar Imaging Thrombolytic Evaluation Trial) and DEFUSE (Diffusion and Perfusion Imaging Evaluation for Understanding Stroke Evolution) studies. In 119 patients (83 treated with IV tissue plasminogen activator), follow-up images were coregistered to acute diffusion images and the lesions manually outlined to their maximal visual extent in diffusion space. Diffusion lesion reversal was defined as voxels of acute diffusion lesion that corresponded to normal brain at follow-up (i.e., final infarct, leukoaraiosis, and cerebrospinal fluid (CSF) voxels were excluded from consideration). The appearance of DLR was visually checked for artifacts, the volume calculated, and the impact of adjusting baseline diffusion lesion volume for DLR volume on perfusion-diffusion mismatch analyzed. Median DLR volume reduced from 4.4 to 1.5 mL after excluding CSF/leukoaraiosis. Visual inspection verified 8/119 (6.7%) with true DLR, median volume 2.33 mL. Subtracting DLR from acute diffusion volume altered perfusion-diffusion mismatch (T(max)>6 seconds, ratio>1.2) in 3/119 (2.5%) patients. Diffusion lesion reversal between baseline and 3 to 6 hours DWI was also uncommon (7/65, 11%) and often transient. Clinically relevant DLR is uncommon and rarely alters perfusion-diffusion mismatch. The acute diffusion lesion is generally a reliable signature of the infarct core.

Geography, structure, and evolution of diffusion and perfusion lesions in Diffusion and perfusion imaging Evaluation For Understanding Stroke Evolution (DEFUSE).

BACKGROUND AND PURPOSE: The classical representation of acute ischemic lesions on MRI is a central diffusion-weighted imaging (DWI) lesion embedded in a perfusion-weighted imaging (PWI) lesion. We investigated spatial relationships between final infarcts and early DWI/PWI lesions before and after intravenous thrombolysis in the Diffusion and perfusion imaging Evaluation For Understanding Stroke Evolution (DEFUSE) study. METHODS: Baseline and follow-up DWI and PWI lesions and 30-day fluid-attenuated inversion recovery scans of 32 patients were coregistered. Lesion geography was defined by the proportion of the DWI lesion superimposed by a Tmax (time when the residue function reaches its maximum) >4 seconds PWI lesion; Type 1: >50% overlap and Type 2: < or = 50% overlap. Three-dimensional structure was dichotomized into a single lesion (one DWI and one PWI lesion) versus multiple lesions. Lesion reversal was defined by the percentage of the baseline DWI or PWI lesion not superimposed by the early follow-up DWI or PWI lesion. Final infarct prediction was estimated by the proportion of the final infarct superimposed on the union of the DWI and PWI lesions. RESULTS: Single lesion structure with Type 1 geography was present in only 9 patients (28%) at baseline and 4 (12%) on early follow-up. In these patients, PWI and DWI lesions were more likely to correspond with the final infarcts. DWI reversal was greater among patients with Type 2 geography at baseline. Patients with multiple lesions and Type 2 geography at early follow-up were more likely to have early reperfusion. CONCLUSION: Before thrombolytic therapy in the 3- to 6-hour time window, Type 2 geography is predominant and is associated with DWI reversal. After thrombolysis, both Type 2 geography and multiple lesion structure are associated with reperfusion.

Relationships between cerebral perfusion and reversibility of acute diffusion lesions in DEFUSE: insights from RADAR.

BACKGROUND AND PURPOSE: Acute ischemic lesions with restricted diffusion can resolve after early recanalization. The impact of superimposed perfusion abnormalities on the fate of acute diffusion lesions is unclear. METHODS: Data were obtained from DEFUSE, a prospective multicenter study of patients treated with IV tPA 3 to 6 hours after stroke onset. Thirty-two patients with baseline diffusion and perfusion lesions and 30 day FLAIR scans were coregistered. The acute diffusion lesion was divided into 3 regions according to the Tmax delay of the superimposed perfusion lesion: normal baseline perfusion; mild-moderately hypoperfused (2 s8 s). The reversal rate was calculated as the percentage of the acute diffusion lesion that did not overlap with the final infarct on 30-day FLAIR. Diffusion reversal rates were compared based on whether a favorable clinical response occurred and whether early recanalization was achieved. RESULTS: On average, 54% of the acute diffusion lesion volume had normal perfusion. Diffusion reversal rates were significantly increased among cases with favorable clinical response and in patients with early recanalization, especially in regions with normal baseline perfusion. The portion of the diffusion lesion with normal perfusion had significantly higher mean apparent diffusion coefficient values and reversal rates. CONCLUSIONS: Acute ischemic lesions with restricted diffusion are most likely to recover if reperfusion occurs within 6 hours of symptom onset, and reversibility is associated with early recanalization and favorable clinical outcome. We propose the term RADAR (Reversible Acute Diffusion lesion Already Reperfused) to describe regions of acute restricted diffusion with normal perfusion.