Simone Orlandini

Weather-Related Changes in 24-Hour Blood Pressure Profile. Effects of Age and Implications for Hypertension Management

A downward titration of antihypertensive drug regimens in summertime is often performed on the basis of seasonal variations of clinic blood pressure (BP). However, little is known about the actual interaction between outdoor air temperature and the effects of antihypertensive treatment on ambulatory BP. The combined effects of aging, treatment, and daily mean temperature on clinic and ambulatory BP were investigated in 6404 subjects referred to our units between October 1999 and December 2003. Office and mean 24-hour systolic BP, as well as morning pressure surge, were significantly lower in hot (>90th percentiles of air temperature; 136±19, 130±14, and 33.3±16.1 mm Hg; P<0.05 for all), and higher in cold (<10th percentiles) days (141±12, 133±11, and 37.3±9.5 mm Hg; at least P<0.05 for all) when compared with intermediate days (138±18, 132±14, and 35.3±15.4 mm Hg). At regression analysis, 24-hour and daytime systolic pressure were inversely related to temperature (P<0.01 for all). Conversely, nighttime systolic pressure was positively related to temperature (P<0.02), with hot days being associated with higher nighttime pressure. Air temperature was identified as an independent predictor of nighttime systolic pressure increase in the group of elderly treated hypertensive subjects only. No significant relationship was found between air temperature and heart rate. Our results show for the first time that hot weather is associated with an increase in systolic pressure at night in treated elderly hypertensive subjects. This may be because of a nocturnal BP escape from the effects of a lighter summertime drug regimen and may have important implications for seasonal modulation of antihypertensive treatment.

Seasonal blood pressure changes: an independent relationship with temperature and daylight hours.

Seasonal blood pressure (BP) changes have been found to be related to either outdoor or indoor temperature. No information regarding the independent effects of temperature measured proximally to the patient, the personal-level environmental temperature (PET), is available. Inclusion of daylight hours in multivariate analysis might allow exploring the independent interaction of BP with seasonality. To investigate whether ambulatory BP monitoring is affected by PET or by seasonality, 1897 patients referred to our hypertension units underwent ambulatory BP monitoring with a battery-powered temperature data logger fitted to the carrying pouch of the monitor. Predictors of 24-hour daytime and nighttime BP and of morning BP surge were investigated with a multivariate stepwise regression model, including age, sex, body mass index, antihypertensive treatment, office BP, ambulatory heart rate, PET, relative humidity, atmospheric pressure, and daylight hours as independent variables. At adjusted regression analysis, daytime systolic BP was negatively related to PET (−0.14; 95% confidence interval, −0.25 to −0.02); nighttime BP was positively related to daylight hours (0.63; 0.37–0.90); and morning BP surge was negatively related to daylight hours (−0.54; −0.87 to −0.21). These results provide new evidence that PET and seasonality (daylight hours) are 2 independent predictors of ambulatory BP monitoring.Seasonal blood pressure (BP) changes have been found to be related to either outdoor or indoor temperature. No information regarding the independent effects of temperature measured proximally to the patient, the personal-level environmental temperature (PET), is available. Inclusion of daylight hours in multivariate analysis might allow exploring the independent interaction of BP with seasonality. To investigate whether ambulatory BP monitoring is affected by PET or by seasonality, 1897 patients referred to our hypertension units underwent ambulatory BP monitoring with a battery-powered temperature data logger fitted to the carrying pouch of the monitor. Predictors of 24-hour daytime and nighttime BP and of morning BP surge were investigated with a multivariate stepwise regression model, including age, sex, body mass index, antihypertensive treatment, office BP, ambulatory heart rate, PET, relative humidity, atmospheric pressure, and daylight hours as independent variables. At adjusted regression analysis, daytime systolic BP was negatively related to PET (−0.14; 95% confidence interval, −0.25 to −0.02); nighttime BP was positively related to daylight hours (0.63; 0.37–0.90); and morning BP surge was negatively related to daylight hours (−0.54; −0.87 to −0.21). These results provide new evidence that PET and seasonality (daylight hours) are 2 independent predictors of ambulatory BP monitoring. # Novelty and Significance {#article-title-25}

Climate change and agriculture: introductory editorial

There seems to be little doubt that the global climate is changing, partly due to natural factors, and in part due to forcing by human activities. However, there are still uncertainties about the extent to which human activity (including agricultural activity) has contributed to the current changes and could influence the future climate. Inevitably, climate and its variability, including the ongoing current changes at various spatial and temporal scales, must impact on agricultural activities. A major challenge for the agricultural industry worldwide is to feed the world population that has been projected to increase by 50% from 6 billion in 2000 to 9 billion in 2050. Most of the increase occurred in the less developed countries, where the current food production is often low. But, although the proportion of hungry people in the world is far below that of 1970, FAO’s current estimate of the number of undernourished people in the world in 2008 was 915 million, the highest over the past 30–40 years (FAO 2009). History suggests that we can be optimistic about achieving appropriate increases in food production. Nevertheless, agriculture must adapt to a changing, and probably more variable, climate and simultaneously reduce emissions and other human impacts, which contribute to global warming. We need to develop and implement farming systems that produce more, from lower inputs, and that do not predjudice the future (i.e. are more sustainable) than the current systems. A key focus of much current research around the world is to predict future changes in climate and to suggest how these changes will curtail current agricultural systems at individual locations. Thus, the Journal of Agricultural Science, Cambridge has decided to inaugurate a ‘special topic’ of Climate Change and Agriculture. In this issue, we launch the series that will continue in future issues. The series will concentrate mainly on the effects of changing climate on agricultural activity but will also consider the impacts of agriculture on climate. One group of papers deals with estimating climate change and documenting or predicting its effects on current agricultural systems, activity and outputs as well as estimating or predicting agricultural impacts from future climate change. The variability in climate, i.e. changing weather conditions from season to season, has a significant impact on agricultural productivity. There are several seasonal climate variations, such as the El Nino Southern Oscillation or the North Atlantic Oscillation, which are important in determining seasonal weather patterns and can impact on crop yields. Studying how current climatic variability influences crop yields is not only important in providing a baseline for estimation of future impacts, but it can also give insights into potentially useful crop prediction methods. Climate factors represent one of the main inputs for plant growth and have a direct effect on many plant physiological processes such as the onset and duration of phenological stages. Over the past decades, temperatures have been increasing and this has led to earlier start dates of crop stages and even shortening the duration of stages for certain species. This has implications for determining which crop varieties farmers can best grow at a certain location. Varieties developed or adapted to a certain location over the past 30 years may not be the best varieties to grow in the future. Integrating cropmodels with climate change scenarios can provide important information on whether farmers could or should replace the current crops or crop varieties with ones grown elsewhere in a region or continent, whether more research is needed to develop new varieties or * To whom all correspondence should be addressed. Email: r.e.l.naylor@abdn.ac.uk Journal of Agricultural Science (2010), 148, 499–500.

Innovative Approaches Helpful to Enhance Knowledge on Weather-Related Stroke Events Over a Wide Geographical Area and a Large Population

Background and Purpose— Results on the effect of weather on stroke occurrences are still confusing and controversial. The aim of this study was to retrospectively investigate in Tuscany (central Italy) the weather-related stroke events through the use of an innovative source of weather data (Reanalysis) together with an original statistical approach to quantify the prompt/delayed health effects of both cold and heat exposures. Methods— Daily stroke hospitalizations and meteorologic data from the Reanalysis 2 Achieve were obtained for the period 1997 to 2007. Generalized linear and additive models and an innovative modeling approach, the constrained segmented distributed lag model, were applied. Results— Both daily averages and day-to-day changes of air temperature and geopotential height (a measure that approximates the mean surface pressure) were selected as independent predictors of all stroke occurrences. In particular, a 5°C temperature decrease was associated with 16.5% increase of primary intracerebral hemorrhage of people ≥65 years of age. A general short-term cold effect on hospitalizations limited to 1 week after exposure was observed and, for the first time, a clear harvesting effect (deficit of hospitalization) for cold-related primary intracerebral hemorrhage was described. Day-to-day changes of meteorologic parameters disclosed characteristic U- and J-shaped relationships with stroke occurrences. Conclusions— Thanks to the intrinsic characteristic of Reanalysis, these results might simply be implemented in an operative forecast system regarding weather-related stroke events with the aim to develop preventive health plans.

A synoptic approach to weather conditions discloses a relationship with ambulatory blood pressure in hypertensives.

BACKGROUND Higher blood pressure (BP) values in cold than in hot months has been documented in hypertensives. These changes may potentially contribute to the observed excess winter cardiovascular mortality. However, the association with weather has always been investigated by considering the relationship with a single variable rather than considering the combination of ground weather variables characterizing a specific weather pattern (air mass (AM)). METHODS We retrospectively investigate in Florence (Italy) the relationship between BP and specific AMs in hypertensive subjects (n = 540) referred to our Hypertension Unit for 24-h ambulatory BP monitoring during the period of the year characterized by the highest weather variability (winter). Five different winter daily AMs were classified according to the combination of ground weather data (air temperature, cloud cover, relative humidity, atmospheric pressure, wind speed, and direction). RESULTS Multiple variable analysis selected the AM as a significant predictor of mean 24-h BP (P < 0.01 for diastolic BP (DBP) and P < 0.05 for systolic BP (SBP)), daytime DBP (P < 0.001) and nighttime BP (P < 0.01 for both SBP and DBP), with higher BP values observed in cyclonic (unstable, cloudy, and mild weather) than in anticyclonic (settled, cloudless, and cold weather) days. When the association with 2-day sequences of AMs was considered, an increase in ambulatory BP followed a sudden day-to-day change of weather pattern going from anticyclonic to cyclonic days. CONCLUSIONS The weather considered as a combination of different weather variables may affect BP. The forecast of a sudden change of AM could provide important information helpful for hypertensives during winter.

Analysis of the relationships between climate variability and grapevine phenology in the Nobile di Montepulciano wine production area.

Climate represents one of the main inputs necessary for plants to complete their vegetative–productive cycle, having a direct effect on the onset and duration of phenological stages and development of crops. Equally important are its indirect effects, affecting field operations such as the application of fertilizer, pruning and crop protection, finally determining the yield. In the present study, phenological stages of the Sangiovese grapevine for the production of Nobile di Montepulciano wine were analysed and related to historical series of meteorological information (since 1970 in Tuscany, Italy). Weather conditions were described through large-scale meteorological information; in particular geopotential height at the 500 hPa level (500 hPa GPH) and North Atlantic Oscillation (NAO) index were considered. All data were provided by the National Oceanic and Atmospheric Administration-Cooperative Institute for Research in Environmental Sciences (NOAA-CIRES) Climate Diagnostics Center, Boulder, Colorado, USA, available from the NOAA-CIRES website ( http://www.cdc.noaa.gov/ ) and processed by the National Center for Environmental Prediction/National Center for Atmospheric Research (NCEP/NCAR) Reanalysis Project. Conventional meteorological data, such as air temperature and cumulated rainfall, from ground weather stations were also used. The effects of meteorological parameters on crop phenology (bud-break, flowering and harvest time) were investigated by means of regression analysis, while teleconnections between phenological data and large-scale meteo-climatological data were analysed through correlation maps created using the interactive plotting and analysis link from the NOAA-CIRES website ( http://www.cdc.noaa.gov ). All correlations were calculated on a monthly to a multi-monthly basis, and also in relation to the different physiological stages of the crop, from 1970 to 2006. The climate change and variability impact on the crop was investigated by trend analysis of meteorological information and its effect on the onset of grapevine phenological stages. The results demonstrated that large-scale meteorological information has a significant effect on the onset of the phenological stages of grapevine. In particular, winter NAO was negatively correlated with bud-break and flowering dates, while GPH of February–March, March–May and May–September were negatively correlated with bud-break, flowering and harvest dates, respectively. The trend analysis demonstrated that the change and variability of climate, due to global warming, directly affects the development of grapevine leading to an anticipation of all considered phenophases.

Effect of agrometeorological parameters on the phenology of pollen emission and production of olive trees (Olea europea L.)

The pollination period and pollen concentrationof olive trees (Oleaeuropea L.) and olive production were analysedfor Prato and Florenceusing a data set of 8 years (1991–1998).Meteorological data have been usedto obtain information about weather conditionsduring vegetative seasonsand correlations were found both for thephenology and yield.The results showed that air temperatureprevious to the onset of floweringis of great importance in determining thereproductive cycle of olive treebut the chill period in January and Februaryshould also be considered.Olive pollen collected during thepollination period was positivelycorrelated with the production level for bothsites. Weather conditionfollowing pollination were also taken intoaccount for a better assessmentof the final yield.

Optically-assessed preformed flavonoids and susceptibility of grapevine to Plasmopara viticola under different light regimes

The role of flavonoids in the response of plants to Plasmopara viticola, the phytopathogen agent of downy mildew, was studied in the Vitis vinifera L. cultivar Sangiovese. Grapevines in the vineyard were exposed to two light regimes, 100% and 35% of full sunlight in order to induce differences in total leaf polyphenolic content. Epidermal leaf phenolic compounds were assessed optically, using the Dualex chlorophyll fluorescence-based portable leaf-clip. Dualex data were calibrated by means of HPLC analysis of extracts from the same measured leaves. Good correlations were obtained with total flavonoid contents, which consist mainly of quercetin 3-O-glucuronide. From the Dualex non-destructive measurements, we showed that full-sun exposed leaves contained 75% more flavonoids than shaded leaves. Inoculation of leaves with P. viticola sporangia resulted in a significantly lower infected leaf area in sun-lit leaves compared with shaded ones, as seen from subsequent analysis of the downy mildew severity. These results indicated an inverse relationship between preformed flavonoids and the susceptibility of grapevines to downy mildew. The rapid optical method for the non-destructive assessment of flavonoids presented here could be useful for large scale screening and predicting V. vinifera susceptibility to P. viticola.

Impacts of Climate Change and Variability on European Agriculture

Climate plays a fundamental role in agriculture because of to its influence on production. All processes are regulated by specific climatic requirements. Furthermore, European agriculture, based on highly developed farming techniques, is mainly oriented to high quality food production that is more susceptible to meteorological hazards. These hazards can modify environment–genotype interactions, which can affect the quality of production. The COST 734 Action (Impacts of Climate Change and Variability on European Agriculture), launched in 2006, is composed of 28 signature countries and is funded by the European Commission. The main objective of the Action is the evaluation of possible impacts arising from climate change and variability on agriculture and the assessment of critical thresholds for various European areas. The Action will concentrate on four different tasks: agroclimatic indices and simulation models, including review and assessment of tools used to relate climate and agricultural processes; evaluation of the current trends of agroclimatic indices and model outputs, including remote sensing; developing and assessing future regional and local scenarios of agroclimatic conditions; and risk assessment and foreseen impacts on agriculture. The work will be carried out by respective Working Groups. This paper presents the results of the analysis of the first phase of inventory activity. Specific questionnaires were disseminated among COST 734 countries to collect information on climate change analysis, studies, and impact at the European level. The results were discussed with respect to their spatial distribution in Europe and to identify possible common long‐ and short‐term strategies for adaptation.

Air temperature-related human health outcomes: current impact and estimations of future risks in Central Italy.

The association between air temperature and human health is described in detail in a large amount of literature. However, scientific publications estimating how climate change will affect the populations health are much less extensive. In this study current evaluations and future predictions of the impact of temperature on human health in different geographical areas have been carried out. Non-accidental mortality and hospitalizations, and daily average air temperatures have been obtained for the 1999-2008 period for the ten main cities in Tuscany (Central Italy). High-resolution city-specific climatologic A1B scenarios centered on 2020 and 2040 have been assessed. Generalized additive and distributed lag models have been used to identify the relationships between temperature and health outcomes stratified by age: general adults (<65), elderly (aged 65-74) and very elderly (≥75). The cumulative impact (over a lag-period of 30 days) of the effects of cold and especially heat, was mainly significant for mortality in the very elderly, with a higher impact on coastal plain than inland cities: 1 °C decrease/increase in temperature below/above the threshold was associated with a 2.27% (95% CI: 0.17-4.93) and 15.97% (95% CI: 7.43-24.51) change in mortality respectively in the coastal plain cities. A slight unexpected increase in short-term cold-related mortality in the very elderly, with respect to the baseline period, is predicted for the following years in half of the cities considered. Most cities also showed an extensive predicted increase in short-term heat-related mortality and a general increase in the annual temperature-related elderly mortality rate. These findings should encourage efforts to implement adaptation actions conducive to policy-making decisions, especially for planning short- and long-term health intervention strategies and mitigation aimed at preventing and minimizing the consequences of climate change on human health.