BACKGROUND: Low dose rivaroxaban with aspirin reduced major cardiovascular events (MACE) compared to aspirin alone in patients with cardiovascular disease although effects on total events are unknown. METHODS: The COMPASS clinical trial randomized 27,395 participants with chronic coronary and/or peripheral artery disease to rivaroxaban 2.5 mg twice daily plus aspirin 100 mg daily, rivaroxaban 5 mg twice daily alone, or aspirin 100 mg daily. We analyzed total (first and recurrent) MACE outcomes of cardiovascular death, stroke, or myocardial infarction, and the primary safety outcome of major bleeding. Exploratory analyses included on-treatment and net clinical benefit. Total MACE and safety events were modeled for each treatment. RESULTS: MACE events were lowest in rivaroxaban with aspirin (379 first MACE, 432 total MACE) compared with rivaroxaban (448 first, 508 total) or aspirin alone (496 first, 574 total). Rivaroxaban and aspirin reduced total MACE events compared with aspirin alone [HR 0.75, 95% CI 0.66-0.85, P < .0001, number needed to treat for 2 years (NNT2y) of 63]. Total major bleeding was higher for rivaroxaban with aspirin compared to aspirin, but severe bleeding was not increased. The net clinical benefit of rivaroxaban plus aspirin was 20% higher compared with aspirin alone [HR 0.80 (95% CI 16.3%-31.6%)]. Rivaroxaban alone had no benefit on MACE outcomes compared with aspirin alone. MACE outcomes were similar for those on and off randomized treatment. CONCLUSIONS: Low dose rivaroxaban with aspirin significantly reduces first and total cardiovascular events compared with aspirin alone with a NNT2y of 63 and a 20% net clinical benefit. TRIAL REGISTRATION: NCT01776424. https://clinicaltrials.gov/ct2/show/NCT01776424.
- MeSH
- Aspirin MeSH
- inhibitory agregace trombocytů škodlivé účinky MeSH
- inhibitory faktoru Xa MeSH
- kombinovaná farmakoterapie MeSH
- krvácení chemicky indukované MeSH
- lidé MeSH
- nemoci koronárních tepen * farmakoterapie MeSH
- onemocnění periferních arterií * farmakoterapie MeSH
- rivaroxaban MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- randomizované kontrolované studie MeSH
AIMS: To analyse whether the benefits and risks of rivaroxaban plus aspirin vary in patients with comorbidities and receiving multiple drugs. In patients with coronary or peripheral artery disease, adding low-dose rivaroxaban to aspirin reduces cardiovascular events and mortality. Polypharmacy and multimorbidity are frequent in such patients. METHODS AND RESULTS: We describe ischaemic events (cardiovascular death, stroke, or myocardial infarction) and major bleeding in participants from the randomized, double-blind COMPASS study by number of cardiovascular medications and concomitant medical conditions. We compared event rates and hazard ratios (HRs) for rivaroxaban plus aspirin vs. aspirin alone by the number of medications and concomitant conditions, and tested for interaction between polypharmacy or multimorbidity and the antithrombotic regimen. The risk of ischaemic events was higher in patients with more concomitant drugs (HR 1.7, 95% confidence interval 1.5-2.1 for >4 vs. 0-2) and with more comorbidities (HR 2.3, 1.8-2.1 for >3 vs. 0-1). Multimorbidity, but not polypharmacy, was associated with a higher risk of major bleeding. The relative efficacy, safety, and net clinical benefit of rivaroxaban were not affected by the number of drugs or comorbidities. Patients taking more concomitant medications derived the largest absolute reduction in the net clinical outcome with added rivaroxaban (1.1% vs. 0.4% reduction with >4 vs. 0-2 cardiovascular drugs, number needed to treat 91 vs. 250). CONCLUSION: Adding low-dose rivaroxaban to aspirin resulted in benefits irrespective of the number of concomitant drugs or comorbidities. Multiple comorbidities and/or polypharmacy should not dissuade the addition of rivaroxaban to aspirin in otherwise eligible patients.
AIMS: People with diabetes are at high risk for cardiovascular events including heart failure (HF). We examined the effect of the glucagon-like peptide 1 agonist dulaglutide on incident HF events and other cardiovascular outcomes in those with or without prior HF in the randomized placebo-controlled Researching Cardiovascular Events with a Weekly Incretin in Diabetes (REWIND) trial. METHODS AND RESULTS: The REWIND major adverse cardiovascular event (MACE) outcome was the first occurrence of a composite endpoint of non-fatal myocardial infarction, non-fatal stroke, or death from cardiovascular causes (including unknown causes). In this post-hoc analysis, a HF event was defined as an adjudication-confirmed hospitalization or urgent evaluation for HF. Of the 9901 participants studied over a median follow-up of 5.4 years, 213/4949 (4.3%) randomly assigned to dulaglutide and 226/4952 (4.6%) participants assigned to placebo experienced a HF event (hazard ratio [HR] 0.93, 95% confidence interval [CI] 0.77-1.12; p = 0.456). In the 853 (8.6%) participants with HF at baseline, there was no change in either MACE or HF events with dulaglutide as compared to participants without HF (p = 0.44 and 0.19 for interaction, respectively). Combined cardiovascular death and HF events were marginally reduced with dulaglutide compared to placebo (HR 0.88, 95% CI 0.78-1.00; p = 0.050) but unchanged in patients with and without HF at baseline (p = 0.31). CONCLUSIONS: Dulaglutide was not associated with a reduction in HF events in patients with type 2 diabetes regardless of baseline HF status over 5.4 years of follow-up.
- MeSH
- diabetes mellitus 2. typu * komplikace farmakoterapie epidemiologie MeSH
- hypoglykemika terapeutické užití škodlivé účinky MeSH
- inkretiny terapeutické užití MeSH
- kardiovaskulární nemoci * epidemiologie MeSH
- lidé MeSH
- srdeční selhání * farmakoterapie epidemiologie chemicky indukované MeSH
- výsledek terapie MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- randomizované kontrolované studie MeSH
AIMS: To describe outcomes of patients with chronic coronary artery disease (CAD) and/or peripheral artery disease (PAD) enrolled in the Cardiovascular Outcomes for People Using Anticoagulation Strategies (COMPASS) randomized trial who were treated with the combination of rivaroxaban 2.5 mg twice daily and aspirin 100 mg once daily during long-term open-label extension (LTOLE). METHODS AND RESULTS: Of the 27 395 patients enrolled in COMPASS, 12 964 (mean age at baseline 67.2 years) from 455 sites in 32 countries were enrolled in LTOLE and treated with the combination of rivaroxaban and aspirin for a median of 374 additional days (range 1-1191 days). During LTOLE, the incident events per 100 patient years were as follows: for the primary outcome [cardiovascular death, stroke, or myocardial infarction (MI)] 2.35 [95% confidence interval (CI) 2.11-2.61], mortality 1.87 (1.65-2.10), stroke 0.62 (0.50-0.76), and MI 1.02 (0.86-1.19), with CIs that overlapped those seen during the randomized treatment phase with the combination of rivaroxaban and aspirin. The incidence rates for major and minor bleeding were 1.01 (0.86-1.19) and 2.49 (2.24-2.75), compared with 1.67 (1.48-1.87) and 5.11 (95% CI 4.77-5.47), respectively, during the randomized treatment phase with the combination. CONCLUSION: In patients with chronic CAD and/or PAD, extended combination treatment for a median of 1 year and a maximum of 3 years was associated with incidence rates for efficacy and bleeding that were similar to or lower than those seen during the randomized treatment phase, without any new safety signals.
- MeSH
- Aspirin MeSH
- cévní mozková příhoda * epidemiologie MeSH
- infarkt myokardu * epidemiologie MeSH
- kojenec MeSH
- kombinovaná farmakoterapie MeSH
- lidé MeSH
- onemocnění periferních arterií * diagnóza farmakoterapie epidemiologie MeSH
- rivaroxaban MeSH
- Check Tag
- kojenec MeSH
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- randomizované kontrolované studie MeSH
AIM: To assess the occurrence of atrial fibrillation or atrial flutter (atrial arrhythmias [AA]) in patients with type 2 diabetes treated with once-weekly subcutaneous dulaglutide versus placebo. MATERIALS AND METHODS: Patients without electrocardiographic (ECG)-confirmed AA at baseline and randomized in the REWIND trial were assessed for the development of AA based on an annual ECG. Additional analyses included whether dulaglutide compared with placebo reduced the composite outcome of AA or death, AA or cardiovascular death, AA or stroke and AA or heart failure. RESULTS: Among 9543 participants (mean age 66 ± 7 years, with cardiovascular risk factors and 31% with previous cardiovascular disease) without AA at entry in the trial, 524 patients (5.5%) had at least one episode of AA during the median 5.4 years of follow-up. Incident AA occurred in 269 of the 4769 participants allocated to dulaglutide (5.6%), at a rate of 10.7 per 1000 person-years, versus 255 of the 4774 allocated to placebo (5.3%), at a rate of 10.5 per 1000 person-years (P = .59). There was also no effect of dulaglutide on the composite outcome of AA and death or AA and heart failure. CONCLUSION: This post hoc analysis of data from the REWIND trial showed that treatment with dulaglutide was not associated with a reduced incidence of AA in this at-risk group of patients with type 2 diabetes.
- MeSH
- diabetes mellitus 2. typu * komplikace farmakoterapie epidemiologie MeSH
- fibrilace síní * komplikace farmakoterapie epidemiologie MeSH
- glukagonu podobné peptidy analogy a deriváty MeSH
- hypoglykemika MeSH
- imunoglobuliny - Fc fragmenty škodlivé účinky MeSH
- lidé středního věku MeSH
- lidé MeSH
- rekombinantní fúzní proteiny škodlivé účinky MeSH
- senioři MeSH
- Check Tag
- lidé středního věku MeSH
- lidé MeSH
- senioři MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- randomizované kontrolované studie MeSH
AIMS: Rosuvastatin (10 mg per day) compared with placebo reduced major adverse cardiovascular (CV) events by 24% in 12 705 participants at intermediate CV risk after 5.6 years. There was no benefit of blood pressure (BP) lowering treatment in the overall group, but a reduction in events in the third of participants with elevated systolic BP. After cessation of all the trial medications, we examined whether the benefits observed during the active treatment phase were sustained, enhanced, or attenuated. METHODS AND RESULTS: After the randomized treatment period (5.6 years), participants were invited to participate in 3.1 further years of observation (total 8.7 years). The first co-primary outcome for the entire length of follow-up was the composite of myocardial infarction, stroke, or CV death [major adverse cardiovascular event (MACE)-1], and the second was MACE-1 plus resuscitated cardiac arrest, heart failure, or coronary revascularization (MACE-2). In total, 9326 (78%) of 11 994 surviving Heart Outcomes Prevention Evaluation (HOPE)-3 subjects consented to participate in extended follow-up. During 3.1 years of post-trial observation (total follow-up of 8.7 years), participants originally randomized to rosuvastatin compared with placebo had a 20% additional reduction in MACE-1 [95% confidence interval (CI), 0.64-0.99] and a 17% additional reduction in MACE-2 (95% CI 0.68-1.01). Therefore, over the 8.7 years of follow-up, there was a 21% reduction in MACE-1 (95% CI 0.69-0.90, P = 0.005) and 21% reduction in MACE-2 (95% CI 0.69-0.89, P = 0.002). There was no benefit of BP lowering in the overall study either during the active or post-trial observation period, however, a 24% reduction in MACE-1 was observed over 8.7 years. CONCLUSION: The CV benefits of rosuvastatin, and BP lowering in those with elevated systolic BP, compared with placebo continue to accrue for at least 3 years after cessation of randomized treatment in individuals without cardiovascular disease indicating a legacy effect. TRIAL REGISTRATION NUMBER: NCT00468923.
- MeSH
- cholesterol MeSH
- dvojitá slepá metoda MeSH
- infarkt myokardu * prevence a kontrola MeSH
- kardiovaskulární nemoci * prevence a kontrola MeSH
- krevní tlak MeSH
- lidé MeSH
- následné studie MeSH
- rizikové faktory MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- randomizované kontrolované studie MeSH
OBJECTIVE: Recent European Guidelines for Diabetes, Prediabetes and Cardiovascular Diseases introduced a shift in managing patients with type 2 diabetes at high risk for or established cardiovascular (CV) disease by recommending GLP-1 receptor agonists and SGLT-2 inhibitors as initial glucose-lowering therapy. This is questioned since outcome trials of these drug classes had metformin as background therapy. In this post hoc analysis, the effect of dulaglutide on CV events was investigated according to the baseline metformin therapy by means of a subgroup analysis of the Researching Cardiovascular Events with a Weekly Incretin in Diabetes (REWIND) trial. RESEARCH DESIGN AND METHODS: Patients in REWIND (n = 9901; women: 46.3%; mean age: 66.2 years) had type 2 diabetes and either a previous CV event (31%) or high CV risk (69%). They were randomized (1:1) to sc. dulaglutide (1.5 mg/weekly) or placebo in addition to standard of care. The primary outcome was the first of a composite of nonfatal myocardial infarction, nonfatal stroke, and death from cardiovascular or unknown causes. Key secondary outcomes included a microvascular composite endpoint, all-cause death, and heart failure. The effect of dulaglutide in patients with and without baseline metformin was evaluated by a Cox regression hazard model with baseline metformin, dulaglutide assignment, and their interaction as independent variables. Adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) were estimated by a Cox regression model with adjustments for factors differing at baseline between people with vs. without metformin, identified using the backward selection. RESULTS: Compared to patients with metformin at baseline (n = 8037; 81%), those without metformin (n = 1864; 19%) were older and slightly less obese and had higher proportions of women, prior CV events, heart failure, and renal disease. The primary outcome occurred in 976 (12%) participants with baseline metformin and in 281 (15%) without. There was no significant difference in the effect of dulaglutide on the primary outcome in patients with vs. without metformin at baseline [HR 0.92 (CI 0.81-1.05) vs. 0.78 (CI 0.61-0.99); interaction P = 0.18]. Findings for key secondary outcomes were similar in patients with and without baseline metformin. CONCLUSION: This analysis suggests that the cardioprotective effect of dulaglutide is unaffected by the baseline use of metformin therapy.
- MeSH
- diabetes mellitus 2. typu * komplikace farmakoterapie epidemiologie MeSH
- glukagonu podobné peptidy analogy a deriváty MeSH
- hypoglykemika terapeutické užití MeSH
- imunoglobuliny - Fc fragmenty MeSH
- kardiovaskulární nemoci * epidemiologie prevence a kontrola MeSH
- lidé středního věku MeSH
- lidé MeSH
- metformin * terapeutické užití MeSH
- nemoci cév * MeSH
- receptor pro glukagonu podobný peptid 1 MeSH
- rekombinantní fúzní proteiny MeSH
- senioři MeSH
- výsledek terapie MeSH
- Check Tag
- lidé středního věku MeSH
- lidé MeSH
- mužské pohlaví MeSH
- senioři MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- randomizované kontrolované studie MeSH
BACKGROUND: Surgical occlusion of the left atrial appendage has been hypothesized to prevent ischemic stroke in patients with atrial fibrillation, but this has not been proved. The procedure can be performed during cardiac surgery undertaken for other reasons. METHODS: We conducted a multicenter, randomized trial involving participants with atrial fibrillation and a CHA2DS2-VASc score of at least 2 (on a scale from 0 to 9, with higher scores indicating greater risk of stroke) who were scheduled to undergo cardiac surgery for another indication. The participants were randomly assigned to undergo or not undergo occlusion of the left atrial appendage during surgery; all the participants were expected to receive usual care, including oral anticoagulation, during follow-up. The primary outcome was the occurrence of ischemic stroke (including transient ischemic attack with positive neuroimaging) or systemic embolism. The participants, research personnel, and primary care physicians (other than the surgeons) were unaware of the trial-group assignments. RESULTS: The primary analysis population included 2379 participants in the occlusion group and 2391 in the no-occlusion group, with a mean age of 71 years and a mean CHA2DS2-VASc score of 4.2. The participants were followed for a mean of 3.8 years. A total of 92.1% of the participants received the assigned procedure, and at 3 years, 76.8% of the participants continued to receive oral anticoagulation. Stroke or systemic embolism occurred in 114 participants (4.8%) in the occlusion group and in 168 (7.0%) in the no-occlusion group (hazard ratio, 0.67; 95% confidence interval, 0.53 to 0.85; P = 0.001). The incidence of perioperative bleeding, heart failure, or death did not differ significantly between the trial groups. CONCLUSIONS: Among participants with atrial fibrillation who had undergone cardiac surgery, most of whom continued to receive ongoing antithrombotic therapy, the risk of ischemic stroke or systemic embolism was lower with concomitant left atrial appendage occlusion performed during the surgery than without it. (Funded by the Canadian Institutes of Health Research and others; LAAOS III ClinicalTrials.gov number, NCT01561651.).
- MeSH
- antikoagulancia terapeutické užití MeSH
- aplikace orální MeSH
- cévní mozková příhoda epidemiologie prevence a kontrola MeSH
- embolie epidemiologie prevence a kontrola MeSH
- fibrilace síní farmakoterapie chirurgie MeSH
- kardiochirurgické výkony MeSH
- kombinovaná terapie MeSH
- lidé středního věku MeSH
- lidé MeSH
- peroperační komplikace epidemiologie MeSH
- pooperační komplikace epidemiologie MeSH
- riziko MeSH
- senioři MeSH
- síňové ouško chirurgie MeSH
- stupeň závažnosti nemoci MeSH
- Check Tag
- lidé středního věku MeSH
- lidé MeSH
- mužské pohlaví MeSH
- senioři MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- multicentrická studie MeSH
- práce podpořená grantem MeSH
- randomizované kontrolované studie MeSH
AIMS: Secondary prevention in patients with coronary artery disease and peripheral artery disease involves antithrombotic therapy and optimal control of cardiovascular risk factors. In the Cardiovascular Outcomes for People Using Anticoagulation Strategies (COMPASS) study, adding low-dose rivaroxaban on top of aspirin lowered cardiovascular events, but there is limited data about risk factor control in secondary prevention. We studied the association between risk factor status and outcomes, and the impact of risk factor status on the treatment effect of rivaroxaban, in a large contemporary population of patients with coronary artery disease or peripheral artery disease. METHODS AND RESULTS: We reported ischemic events (cardiovascular death, stroke, or myocardial infarction) in participants from the randomized, double-blind COMPASS study by individual risk factor (blood pressure, smoking status, cholesterol level, presence of diabetes, body mass index, and level of physical activity), and by number of risk factors. We compared rates and hazard ratios of patients treated with rivaroxaban plus aspirin vs aspirin alone within each risk factor category and tested for interaction between risk factor status and antithrombotic regimen. Complete baseline risk factor status was available in 27,117 (99%) patients. Status and number of risk factors were both associated with increased risk of ischemic events. Rates of ischemic events (hazard ratio 2.2; 95% confidence interval 1.8-2.6) and cardiovascular death (hazard ratio 2.0; 1.5-2.7) were more than twofold higher in patients with 4-6 compared with 0-1 risk factors (p < 0.0001 for both). Rivaroxaban reduced event rates independently of the number of risk factors (p interaction 0.93), with the largest absolute benefit in patients with the highest number of risk factors. CONCLUSION: More favorable risk factor status and low-dose rivaroxaban were independently associated with lower risk of cardiovascular events.
- MeSH
- antikoagulancia aplikace a dávkování škodlivé účinky MeSH
- Aspirin aplikace a dávkování škodlivé účinky MeSH
- časové faktory MeSH
- chronická nemoc MeSH
- dvojitá slepá metoda MeSH
- fibrinolytika aplikace a dávkování škodlivé účinky MeSH
- hodnocení rizik MeSH
- inhibitory faktoru Xa aplikace a dávkování škodlivé účinky MeSH
- kombinovaná farmakoterapie MeSH
- lidé středního věku MeSH
- lidé MeSH
- nemoci koronárních tepen diagnostické zobrazování farmakoterapie mortalita MeSH
- onemocnění periferních arterií diagnostické zobrazování farmakoterapie mortalita MeSH
- prospektivní studie MeSH
- recidiva MeSH
- rivaroxaban aplikace a dávkování škodlivé účinky MeSH
- rizikové faktory kardiovaskulárních chorob MeSH
- sekundární prevence * MeSH
- senioři MeSH
- výsledek terapie MeSH
- Check Tag
- lidé středního věku MeSH
- lidé MeSH
- mužské pohlaví MeSH
- senioři MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- multicentrická studie MeSH
- práce podpořená grantem MeSH
- randomizované kontrolované studie MeSH
BACKGROUND: Patients with established coronary artery disease or peripheral artery disease often have diabetes mellitus. These patients are at high risk of future vascular events. METHODS: In a prespecified analysis of the COMPASS trial (Cardiovascular Outcomes for People Using Anticoagulation Strategies), we compared the effects of rivaroxaban (2.5 mg twice daily) plus aspirin (100 mg daily) versus placebo plus aspirin in patients with diabetes mellitus versus without diabetes mellitus in preventing major vascular events. The primary efficacy end point was the composite of cardiovascular death, myocardial infarction, or stroke. Secondary end points included all-cause mortality and all major vascular events (cardiovascular death, myocardial infarction, stroke, or major adverse limb events, including amputation). The primary safety end point was a modification of the International Society on Thrombosis and Haemostasis criteria for major bleeding. RESULTS: There were 10 341 patients with diabetes mellitus and 17 054 without diabetes mellitus in the overall trial. A consistent and similar relative risk reduction was seen for benefit of rivaroxaban plus aspirin (n=9152) versus placebo plus aspirin (n=9126) in patients both with (n=6922) and without (n=11 356) diabetes mellitus for the primary efficacy end point (hazard ratio, 0.74, P=0.002; and hazard ratio, 0.77, P=0.005, respectively, Pinteraction=0.77) and all-cause mortality (hazard ratio, 0.81, P=0.05; and hazard ratio, 0.84, P=0.09, respectively; Pinteraction=0.82). However, although the absolute risk reductions appeared numerically larger in patients with versus without diabetes mellitus, both subgroups derived similar benefit (2.3% versus 1.4% for the primary efficacy end point at 3 years, Gail-Simon qualitative Pinteraction<0.0001; 1.9% versus 0.6% for all-cause mortality, Pinteraction=0.02; 2.7% versus 1.7% for major vascular events, Pinteraction<0.0001). Because the bleeding hazards were similar among patients with and without diabetes mellitus, the prespecified net benefit for rivaroxaban appeared particularly favorable in the patients with diabetes mellitus (2.7% versus 1.0%; Gail-Simon qualitative Pinteraction=0.001). CONCLUSIONS: In stable atherosclerosis, the combination of aspirin plus rivaroxaban 2.5 mg twice daily provided a similar relative degree of benefit on coronary, cerebrovascular, and peripheral end points in patients with and without diabetes mellitus. Given their higher baseline risk, the absolute benefits appeared larger in those with diabetes mellitus, including a 3-fold greater reduction in all-cause mortality. Registration: URL: https://www.clinicaltrials.gov; Unique identifier: NCT01776424.
- MeSH
- antikoagulancia aplikace a dávkování MeSH
- Aspirin aplikace a dávkování MeSH
- diabetes mellitus krev farmakoterapie epidemiologie MeSH
- dvojitá slepá metoda MeSH
- inhibitory agregace trombocytů aplikace a dávkování MeSH
- inhibitory faktoru Xa MeSH
- kardiovaskulární nemoci krev farmakoterapie epidemiologie MeSH
- kombinovaná farmakoterapie MeSH
- lidé středního věku MeSH
- lidé MeSH
- rivaroxaban aplikace a dávkování MeSH
- senioři MeSH
- Check Tag
- lidé středního věku MeSH
- lidé MeSH
- mužské pohlaví MeSH
- senioři MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- multicentrická studie MeSH
- práce podpořená grantem MeSH
- randomizované kontrolované studie MeSH
- srovnávací studie MeSH