Ruta Babarskiene

The association between phenomena on the Sun, geomagnetic activity, meteorological variables, and cardiovascular characteristic of patients with myocardial infarction

It has been found that solar and geomagnetic activity affects the cardiovascular system. Some evidence has been reported on the increase in the rate of myocardial infarction, stroke and myocardial infarction related deaths during geomagnetic storms. We investigated the association between cardiovascular characteristics of patients, admitted for myocardial infarction with ST elevation (STEMI), and geomagnetic activity (GMA), solar proton events (SPE), solar flares, and meteorological variables during admission. The data of 1,979 patients hospitalized at the Hospital of Lithuanian University of Health Sciences (Kaunas) were analyzed. We evaluated the association between environmental variables and patient’s characteristics by multivariate logistic regression, controlling patient’s gender and age. Two days after geomagnetic storms the risk of STEMI was over 1.5 times increased in patients who had a medical history of myocardial infarction, stable angina, renal or pulmonary diseases. The dose–response association between GMA level and STEMI risk for patients with renal diseases in history was observed. Two days after SPE the risk of STEMI in patients with stable angina in anamnesis was increased over 1.5 times, adjusting by GMA level. The SPE were associated with an increase of risk for patients with renal diseases in history. This study confirms the strongest effect of phenomena in the Sun in high risk patients.

Clinical outcomes in patients with stable coronary artery disease with vs. without a history of myocardial revascularization

Aims The aim was to describe outcomes among patients with stable coronary artery disease (CAD) with or without a history of myocardial revascularization in a large contemporary cohort. Methods and results Patients with stable CAD were selected from the Reduction of Atherothrombosis for Continued Health (REACH) registry. The cohort was divided into patients with ( n = 25 583) and without ( n = 13 133) a history of myocardial revascularization. Crude outcomes were described according to the use and type of revascularization: percutaneous coronary intervention (PCI) or coronary artery bypass surgery (CABG). The primary outcome was cardiovascular (CV) death. At baseline, the non-revascularized group was older and had more CV risk factors. At 36-month median follow-up, previous revascularization was associated with a lower risk of CV death [crude incidence rate (CIR): 6.82 vs. 9.08%, hazard ratio (HR) 0.73 [95% confidence interval (CI) 0.66-0.80]; P < 0.01]. This association was seen for patients with a history of PCI (CIR 5.78 vs. 8.88%, HR 0.64 [0.58-0.71]; P ≤ 0.01), but not with CABG (HR 1.26 [1.14-1.49]; P < 0.01), and was consistent regardless of prior MI and the timing of prior revascularization. Conclusion Among patients with stable CAD, a history of myocardial revascularization was associated with lower CV mortality, particularly when PCI was the mode of revascularization. Coronary artery disease patients managed non-invasively represent a high-risk group.

Effects of weather and heliophysical conditions on emergency ambulance calls for elevated arterial blood pressure.

We hypothesized that weather and space weather conditions were associated with the exacerbation of essential hypertension. The study was conducted during 2009–2010 in the city of Kaunas, Lithuania. We analyzed 13,475 cards from emergency ambulance calls (EACs), in which the conditions for the emergency calls were made coded I.10–I.15. The Kaunas Weather Station provided daily records of air temperature (T), wind speed (WS), relative humidity, and barometric pressure (BP). We evaluated the associations between daily weather variables and daily number of EACs by applying a multivariate Poisson regression. Unfavorable heliophysical conditions (two days after the active-stormy geomagnetic field or the days with solar WS > 600 km/s) increased the daily number of elevated arterial blood pressure (EABP) by 12% (RR = 1.12; 95% confidence interval (CI) 1.04–1.21); and WS ≥ 3.5 knots during days of T < 1.5 °C and T ≥ 12.5 °C by 8% (RR = 1.08; CI 1.04–1.12). An increase of T by 10 °C and an elevation of BP two days after by 10 hPa were associated with a decrease in RR by 3%. An additional effect of T was detected during days of T ≥ 17.5 °C only in females. Women and patients with grade III arterial hypertension at the time of the ambulance call were more sensitive to weather conditions. These results may help in the understanding of the population’s sensitivity to different weather conditions.

Effects of weather conditions on emergency ambulance calls for acute coronary syndromes

The aim of this study was to evaluate the relationship between weather conditions and daily emergency ambulance calls for acute coronary syndromes (ACS). The study included data on 3631 patients who called the ambulance for chest pain and were admitted to the department of cardiology as patients with ACS. We investigated the effect of daily air temperature (T), barometric pressure (BP), relative humidity, and wind speed (WS) to detect the risk areas for low and high daily volume (DV) of emergency calls. We used the classification and regression tree method as well as cluster analysis. The clusters were created by applying the k-means cluster algorithm using the standardized daily weather variables. The analysis was performed separately during cold (October–April) and warm (May–September) seasons. During the cold period, the greatest DV was observed on days of low T during the 3-day sequence, on cold and windy days, and on days of low BP and high WS during the 3-day sequence; low DV was associated with high BP and decreased WS on the previous day. During June–September, a lower DV was associated with low BP, windless days, and high BP and low WS during the 3-day sequence. During the warm period, the greatest DV was associated with increased BP and changing WS during the 3-day sequence. These results suggest that daily T, BP, and WS on the day of the ambulance call and on the two previous days may be prognostic variables for the risk of ACS.

Short-term nitrogen dioxide exposure and geomagnetic activity interaction: contribution to emergency hospitalization for acute coronary syndrome

We investigated whether extremely geomagnetic activity may modify the association between short-term nitrogen dioxide (NO2) exposure and emergency hospitalization for acute coronary syndrome (ACS). A case-crossover study design was used to analyze ACS in 6,594 hospitalized patients at the Clinic of Kaunas, Lithuania. We evaluated the associations between NO2, geomagnetic activity and the rate of emergency admissions for ACS by logistic regression controlling for seasonal variation, weekdays and meteorological factors. Ambient NO2 pollution interquartile range increase (IQR) on the day of admission and previous day (lag 0–1) in patients below 65 years of age increase the risk of ACS equal to 24% (95% CI 0.96–1.60). Evidence of effect modification by combined NO2 and geomagnetic activity was observed in relation to ACS, adjusted OR was 1.61; 95% CI 1.03–2.53. In conclusion, these findings suggest that geomagnetic activity variations may increase the traffic-related air pollution effect on ACS, and highlight environmental factors associated with ischemic heart disease course.