The association between physical activity and cardiovascular events, tumors and all-cause mortality in patients with maintenance hemodialysis with different nutritional status.

The current research focuses on the effects of nutritional supplementation and exercise on dialysis patients, but whether physical activity (PA) can reduce the risk of adverse outcomes for patients with different nutritional status is not clear. The maintenance hemodialysis (MHD) patients were recruited from April 2021 to April 2022. The information of PA was obtained from the international physical activity questionnaire (IPAQ). The outcomes were cardiovascular death, myocardial infarction, stroke, heart failure, atrial fibrillation, tumor and all-cause death. We used COX proportional risk model to estimate the association between PA and the outcomes of MHD patients. Patients are classified into two groups based on geriatric nutritional risk index (GNRI) and classified by age, and we used COX proportional risk model to estimate the association of PA and outcomes in subgroups. The isotemporal substitution model (ISM) was used to estimate the effects of replacing light physical activity (LPA) with moderate physical activity (MPA) or vigorous physical activity (VPA) on risk of cardiovascular events, tumors, and all-cause death in different subgroups. The effects of PA on ankle-brachial index (ABI) and body fat content were analyzed in different IPAQ groups. A total of 241 maintenance hemodialysis patients were included, 105 peoples developed cardiovascular death, myocardial infarction, stroke, heart failure, atrial fibrillation, tumor and all-cause death (43.6%). The median follow-up time was 12 months. MPA reduced the risk of outcome in MHD patients or high GNRI patients (40% vs 39%).In MHD patients who was under 65 years with high GNRI, MPA reduced cardiovascular death, myocardial infarction, stroke, heart failure, atrial fibrillation, tumor and all-cause death by 55%.PA reduced the risk of cardiovascular event by 65%, but did not reduce the risk of tumor or all-cause death. Replacing LPA with VPA did not improve clinical outcomes. It actually increases the risk of heart failure 0.4%. MPA reduced the risk of cardiovascular death, myocardial infarction, stroke, heart failure, atrial fibrillation, tumor, all-cause death in MHD patients under 65 years, while VPA had no health benefit.Trial registration: ChiCTR210050998.

Meta-analysis of the response of marine phytoplankton to nutrient addition and seawater warming.

As an indispensable part of the marine ecosystem, phytoplankton are important prey for zooplankton and various marine animals with important commercial value. The influence of seawater warming and eutrophication on phytoplankton communities is well known, but few studies have explained the effects of the interaction between temperature and nutrients on marine phytoplankton. Through meta-analysis and meta-regression, the phytoplankton responses to the effects of nutrient addition and seawater warming were evaluated in this study. Nitrogen (N) addition led to an increase in phytoplankton biomass, while phosphorus (P) had no significant effect on phytoplankton biomass. However, this result may be biased by the uneven distribution of the research area. N limitation is widespread in the areas where these collected studies were conducted, including many parts of North and South Atlantic and West Pacific Oceans. The key limiting nutrient in other areas lacking corresponding experiments, however, remain unclear. The effect of seawater warming was not significant, which indicates the uncertainty about the effect of temperature on phytoplankton. The results of ANOVA show that nutrient addition and seawater warming had similar effects in various marine habitats (coastal regions, estuaries and open seas), while salinity could have caused the difference in the N effects among the three habitats. Furthermore, our results showed that the impact of temperature depends on nutrient conditions, especially N status, which has rarely been considered before. This result demonstrated the importance of evaluating nutrient limitation patterns when studying climate warming. The impact of rising temperatures may need to be reevaluated because N limitation is common.