A new feedback mechanism linking forests, aerosols, and climate

International audienceThe possible connections between the carbon balance of ecosystems and aerosol-cloud-climate interactions play a significant role in climate change studies. Carbon dioxide is a greenhouse gas, whereas the net effect of atmospheric aerosols is to cool the climate. Here, we investigated the connection between forest-atmosphere carbon exchange and aerosol dynamics in the continental boundary layer by means of multiannual data sets of particle formation and growth rates, of CO2 fluxes, and of monoterpene concentrations in a Scots pine forest in southern Finland. We suggest a new, interesting link and a potentially important feedback among forest ecosystem functioning, aerosols, and climate: Considering that globally increasing temperatures and CO2 fertilization are likely to lead to increased photosynthesis and forest growth, an increase in forest biomass would increase emissions of non-methane biogenic volatile organic compounds and thereby enhance organic aerosol production. This feedback mechanism couples the climate effect of CO2 with that of aerosols in a novel way

A new feedback mechanism linking forests, aerosols, and climate

The possible connections between the carbon balance of ecosystems and aerosol-cloud-climate interactions play a significant role in climate change studies. Carbon dioxide is a greenhouse gas, whereas the net effect of atmospheric aerosols is to cool the climate. Here, we investigated the connection between forest-atmosphere carbon exchange and aerosol dynamics in the continental boundary layer by means of multiannual data sets of particle formation and growth rates, of CO2 fluxes, and of monoterpene concentrations in a Scots pine forest in southern Finland. We suggest a new, interesting link and a potentially important feedback among forest ecosystem functioning, aerosols, and climate: Considering that globally increasing temperatures and CO2 fertilization are likely to lead to increased photosynthesis and forest growth, an increase in forest biomass would increase emissions of non-methane biogenic volatile organic compounds and thereby enhance organic aerosol production. This feedback mechanism couples the climate effect of CO2 with that of aerosols in a novel way

Concomitant use of drugs known to cause interactions with oral antiplatelets—polypharmacy in acute coronary syndrome outpatients in Finland

Purpose: Use of oral antiplatelets (OAPs) is essential for preventing thrombotic events in patients with acute coronary syndrome (ACS). Effects of clopidogrel, prasugrel, and ticagrelor may be enhanced due to pharmacodynamic interactions, but as CYP substrates, they are prone to pharmacokinetic interactions too. The aim was to study polypharmacy in ACS patients following hospital discharge.Methods: This observational drug utilization study linked patient-level data from nationwide registers. The study population consisted of adult ACS patients discharged from Finnish hospitals in 2009–2013. Logistic regression was used to model the probability of drug-drug interactions with odd ratios for predefined predictors such as age, gender, and ACS type.Results: In the cohort of 54,416 ACS patients, 91% of those treated with OAP received clopidogrel. Of clopidogrel-treated patients, 12% purchased warfarin at least once while on clopidogrel treatment. Old age, male sex, ST-elevation myocardial infarction as index event, and a history of previous ACS events were associated with an increased risk of warfarin-OAP interaction (p Conclusions: Warfarin and ibuprofen were the most commonly used concomitant medications causing pharmacodynamic interactions and potentially increasing the risk of bleeding in OAP-treated patients. Esomeprazole and omeprazole were used in clopidogrel-treated patients although there are alternatives available for gastric protection.</p

Usage of PCI and long-term cardiovascular risk in post-myocardial infarction patients: a nationwide registry cohort study from Finland

Background: Despite currently available treatments, the burden of myocardial infarction (MI) morbidity and mortality remains prominent. The aim of this was to investigate the risk of developing subsequent cardiovascular events in MI patients.Methods: This was an observational, retrospective cohort database linkage study using patient level data from Finland. Cox proportional hazards models were used to assess the association of risk between the preselected covariates and incidence of specific outcomes. The primary endpoints were new MI, stroke, cardiovascular mortality and overall mortality.Results: Finnish adult MI patients alive 7 days after discharge in 2009-2012 were included. The study cohort consisted of 32,909 MI patients, of whom 25,875 (79%) survived 12 months without subsequent MI or stroke. ST-elevation MI (STEMI) was associated with lower risk of subsequent MI and overall mortality compared to non-STEMI patients. Percutaneous coronary intervention (PCI) was used two times more often in STEMI patients, but patients with prior stroke were more than two times less likely to have PCI. Dementia/Alzheimer's disease decreased the use of PCI as much as age over 85 years. Female sex was an independent factor for not undergoing PCI (OR 0.75, PConclusions: Risk of cardiovascular events and mortality after MI increases steeply with age. Although at higher risk, aging patients and those with cardiovascular comorbidities are less likely to receive PCI after MI. Female sex is associated with better survival after MI regardless of less intensive treatment in women.</div