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C urrent guidelines recommend the assessment of vascular risk factors, target organ damage, and blood pressure (BP) levels to guide the treatment on primary hypertension. 1 Besides BP levels, other BP-related features, such as the nocturnal dipping 2 or more recently, visit-to-visit or long-term BP variability (BPV), have been independently associated with clinical cardiovascular outcomes in a recent systematic review and meta-analysis. 3 Also, the prognostic value of BPV measured with ambulatory BP monitoring (ABPM) for 24 hours (also value-to-value or short-term BPV) has been evaluated. Data on short-term BPV from 11 populations 4 suggest a positive association between measures of short-term BPV and cardiovascular death or any (fatal and nonfatal) event. Although the contribution of short-term BPV to the prediction of cardiovascular events was shown to be small (<1%), this is still a matter of debate because results from individual studies support significant contributions. 5,6 It has been also suggested that the prognostic significance of BPV on stroke risk is weaker for short-term than for long-term BPV in treated hypertension. 7 However, these data need further investigation taking into account not only between subject BPV but also within subject BPV. Moreover, several indices of short-term BPV have been related to the presence of subclinical damage in one or multiple organs, including the heart, kidney, and vessels, independently of BP levels. 8-10 About the brain, hypertension is a major risk factor for cerebral small vessel disease (CSVD), which is an Abstract-Blood pressure (BP) variability is associated with stroke risk, but less is known about subclinical cerebral small vessel disease (CSVD). We aimed to determine whether CSVD relates to short-term BP variability independently of BP levels and also, whether they improve CSVD discrimination beyond clinical variables and office BP levels. This was a cohort study on asymptomatic hypertensives who underwent brain magnetic resonance imaging and 24-hour ambulatory BP monitoring. Office and average 24-hour, daytime and nighttime BP levels, and several metrics of BP variability (SD, weighted SD, coefficient of variation, and average real variability [ARV]) were calculated. Definition of CSVD was based on the presence of lacunar infarcts and white matter hyperintensity grades. Multivariate analysis and integrated discrimination improvement were performed to assess whether BP variability and levels were independently associated with CSVD and improved its discrimination. Four hundred eighty-seven individuals participated (median age, 64; 47% women). CSVD was identified in 18.9%, related to age, male sex, diabetes mellitus, use of treatment, ambulatory BP monitoring-defined BP levels, and ARV of systolic BP at any period. The highest prevalence (33.7%) was found in subjects with both 24-hour BP levels and ARV elevated. BP levels at any period and ARV (24 hours and nocturnal) emerged as independent predictors of CSVD, and discrimination was incrementally improved ...

We investigated whether there is a direct correlation between plasma fibrinogen levels and the amount of leukoaraiosis (LA) in patients with symptomatic small-vessel disease. The study included 28 patients: 12 with a first-ever lacunar infarction (LI) and 16 with Binswanger’s disease (BD). The mean age was 71 years (SD 8.6), and 21 were men. For each patient, we recorded demographic data, vascular risk factors and the results of blood chemistry analysis including fibrinogen (g/l), hematocrit (decimal fraction) and total serum proteins (g/l). A cerebral MR scan was performed in each patient and an LA score was obtained by an investigator blind to clinical data, using a semiquantified scale in six areas of each cerebral hemisphere (0–4 points in each area, total scoring range 0–48 points). Results: The mean (SD) for the LA score was 18.9 (10.7) and for plasma fibrinogen 3.97 (1.1). Pearson’s and Spearman’s correlation coefficients between fibrinogen and LA score were 0.43 (p = 0.02) and 0.49 (p = 0.007), respectively. Multiple-regression analysis between groups (LI or BD) and fibrinogen versus LA score showed the strongest association for the BD group (p = 0.014) and a direct relation with fibrinogen (p = 0.018). No statistically significant association was found between LA score and age, sex, any vascular risk factor, hematocrit or total serum protein. Conclusion: There is a significant correlation between plasma fibrinogen levels and the amount of LA in patients with symptomatic cerebral small-vessel disease. This result suggests that fibrinogen may be involved in the pathophysiology of LA in these patients.

We examined the relationship between climate variables and grassland area burned in Xilingol, China, from 2001 to 2014 using an autoregressive distributed lag (ARDL) model, and describe the application of this econometric method to studies of climate influences on wildland fire. We show that there is a stationary linear combination of non-stationary climate time series (cointegration) that can be used to reliably estimate the influence of different climate signals on area burned. Our model shows a strong relationship between maximum temperature and grassland area burned. Mean monthly wind speed and monthly hours of sunlight were also strongly associated with area burned, whereas minimum temperature and precipitation were not. Some climate variables like wind speed had significant immediate effects on area burned, the strength of which varied over the 2001–14 observation period (in econometrics terms, a ‘short-run’ effect). The relationship between temperature and area burned exhibited a steady-state or ‘long-run’ relationship. We analysed three different periods (2001–05, 2006–10 and 2011–14) to illustrate how the effects of climate on area burned vary over time. These results should be helpful in estimating the potential impact of changing climate on the eastern Eurasian Steppe.