RESUMO
High blood pressure variability (BPV) has been associated with increased cardiovascular (CV) risk. The effect of dietary salt and renin-angiotensin-aldosterone system (RAAS) activity on short-term BPV in type 2 diabetes mellitus (T2DM) is not well characterised. We aimed to determine the effect of dietary salt (sodium chloride, NaCl) supplementation on 24-h mean arterial BPV (24hBPV) during angiotensin II receptor blocker (telmisartan) use and to evaluate the effects of age, sex, plasma renin activity (PRA) and serum aldosterone on 24hBPV. In a randomised, double-blind, crossover study, patients with T2DM (n = 28), treated with telmisartan received NaCl (100 mmol/24 h) or placebo capsules during 2 weeks of telmisartan. Following a 6-week washout, the protocol was repeated in reverse. 24hBPV was evaluated as a co-efficient of variation [CV (%) = mean/standard deviation] × 100). Twenty-four hour urinary sodium excretion, ambulatory BP and biochemical tests were performed at each phase. Results were analysed using a linear mixed model to generate predicted values for 24hBPV. Predicted 24hBPV was higher with telmisartan vs baseline (p = 0.01), with a trend towards reduced 24hBPV with salt (p = 0.052). Predicted 24hBPV was lower in females (p = 0.017), increasing age (p = 0.001) and increasing PRA (p = 0.011). In patients with T2DM, predicted 24hBPV increased from baseline with telmisartan, but there was no additional increase in predicted 24hBPV with salt supplementation. This suggests that in the short-term, salt supplementation has no apparent deleterious effects on 24hBPV. Long-term studies are required to evaluate the effect of 24hBPV on CV outcomes in patients with T2DM.
Assuntos
Diabetes Mellitus Tipo 2 , Hipertensão , Aldosterona , Angiotensina II , Antagonistas de Receptores de Angiotensina , Pressão Sanguínea , Estudos Cross-Over , Diabetes Mellitus Tipo 2/tratamento farmacológico , Suplementos Nutricionais , Feminino , Humanos , Hipertensão/diagnóstico , Hipertensão/tratamento farmacológico , Renina , Sistema Renina-Angiotensina , Cloreto de Sódio , Cloreto de Sódio na Dieta/efeitos adversosRESUMO
OBJECTIVE: Nutritional support as enteral or parenteral nutrition (PN) is used in hospitalized patients to reduce catabolism. This study compares outcomes of early enteral nutrition (EN) with early PN in hospitalized patients. DESIGN: The authors conducted a metaanalysis of randomized, controlled trials (RCT) comparing early EN with PN. Studies on immunonutrition were excluded. Studies were categorized as medical, surgical, or trauma. PATIENTS: RCTs of early EN/PN were identified by search of 1) MEDLINE (1966-2002), 2) published abstracts from scientific meetings, and 3) bibliographies of relevant articles. MEASUREMENTS AND MAIN RESULTS: Thirty RCTs (ten medical, 11 surgical, and nine trauma) compared early EN with PN. The effect of nutrition type on hospital mortality and complication rates was reported as risk difference (RD%) and hospital length of stay (LOS) as mean weighted difference (MWD days). Missing data, by outcomes, varied from 20% to 63%. As a result of heterogeneity of treatment effects, the DerSimonian-Laird random-effects estimator was reported. There was no differential treatment effect of nutrition type on hospital mortality for all patients (0.6%, p = .4) and subgroups. PN was associated with increases in infective complications (7.9%, p = .001), catheter-related blood stream infections (3.5%, p = .003), noninfective complications (4.9%, p = .04), and hospital LOS (1.2 days, p = .004). There was no effect of nutrition type on technical complications (4.1%, p = .2). EN was associated with a significant increase in diarrheal episodes (8.7%, p = .001). Publication bias was not demonstrated. Metaanalytic regression analysis did not demonstrate any effect of age, time to initiate treatment, and average albumin on mortality estimates. Cumulative metaanalysis showed no change in the mortality estimates with time. CONCLUSION: There was no mortality effect with the type of nutritional supplementation. Although early EN significantly reduced complication rates, this needs to be interpreted in the light of missing data and heterogeneity. The enthusiasm that early EN, as compared with early PN, would reduce mortality appears misplaced.