Optimizing the use of patients' individual outcome information - Development and usability tests of a Chronic Kidney Disease dashboard.

BACKGROUND: Reporting individual clinical and patient-reported outcomes to patients during consultations may add to patients' disease knowledge and activation and stimulate Shared Decision Making (SDM). These outcomes can be presented over time in a clear way by the means of dashboarding. We aimed to systematically develop a Chronic Kidney Disease (CKD) dashboard designed to support consultations, test its usability and explore conditions for optimal use in practice. METHODS: For development a participatory approach with patients and healthcare professionals (HCPs) from three hospitals was used. Working groups and patient focus groups were conducted to identify needs and inform the dashboard's design. Usability was tested in patient interviews. A focus group with HCPs was held to identify conditions for optimal use of the dashboard in daily practice. RESULTS: A dashboard was developed for CKD patients stage 3b-4 visualizing both clinical and patient-reported outcomes over time for use during consultations and accessible for patients at home. Both HCPs and patients indicated that the dashboard can: motivate patients in their treatment by providing feedback on outcomes over time; improve consultation conversations by enhanced preparation of both HCPs and patients; better inform patients, thereby facilitating shared decision making. HCPs and patients both stated that setting a topic agenda for the consultation together is important in effectively discussing the dashboard during consultations. Moreover, the dashboard should not dominate the conversation. Lastly, findings of the usability tests provided design requirements for optimal user-friendliness and clarity. CONCLUSIONS: Dashboarding can be a valuable way of reporting individual outcome information to patients and their clinicians as findings suggest it may stimulate patient activation and facilitate decision making. Co-creation with patients and HCPs was essential for successful development of the dashboard. Gained knowledge from the co-creation process can inform others wishing to develop similar digital tools for use in clinical practice.

Impact of the COVID-19 pandemic on symptoms of anxiety and depression and health-related quality of life in older patients with chronic kidney disease.

BACKGROUND: Older patients with advanced chronic kidney disease are at increased risk for a severe course of the coronavirus disease-2019 (COVID-19) and vulnerable to mental health problems. We aimed to investigate prevalence and associated patient (demographic and clinical) characteristics of mental wellbeing (health-related quality of life [HRQoL] and symptoms of depression and anxiety) before and during the COVID-19 pandemic in older patients with advanced chronic kidney disease. METHODS: An ongoing Dutch multicentre prospective cohort study enrols patients of ≥70 years with an eGFR < 20 mL/min/1.73m2 from October 2018 onward. With additional questionnaires during the pandemic (May-June 2020), disease-related concerns about COVID-19 and general anxiety symptoms were assessed cross-sectionally, and depressive symptoms, HRQoL, and emotional symptoms longitudinally. RESULTS: The 82 included patients had a median age of 77.5 years (interquartile range 73.9-82.1), 77% were male and none had tested positive for COVID-19. Cross-sectionally, 67% of the patients reported to be more anxious about COVID-19 because of their kidney disease, and 43% of the patients stated that their quality of life was reduced due to the COVID-19 pandemic. Compared to pre-COVID-19, the presence of depressive symptoms had increased (11 to 22%; p = .022) and physical HRQoL declined (M = 40.4, SD = 10.1 to M = 36.1, SD = 10.4; p < .001), particularly in males. Mental HRQoL (M = 50.3, SD = 9.6 to M = 50.4, SD = 9.9; p = .913) and emotional symptoms remained similar. CONCLUSIONS: Older patients with advanced chronic kidney disease suffered from disease-related anxiety about COVID-19, increased depressive symptoms and reduced physical HRQoL during the COVID-19 pandemic. The impact of the pandemic on this vulnerable patient group extends beyond increased mortality risk, and awareness of mental wellbeing is important. TRIAL REGISTRATION: The study is registered at the Netherlands Trial Register (NTR), trial number NL7104. Date of registration: 06-06-2018.

Pneumococcal conjugate vaccination response in patients after community-acquired pneumonia, differences in patients with S. pneumoniae versus other pathogens.

OBJECTIVES: The goal of this study is to investigate the immune response to the 13-valent pneumococcal conjugate vaccine (PCV13) in former pneumococcal CAP patients. We hypothesize that an impaired or suboptimal humoral immune response against (specific) pneumococcal serotypes might explain the vulnerability for pneumococcal disease. METHODS: Hospitalised adult CAP patients who participated in two trials (2004-2006 (n=201) and, 2007-2009 (n=304)) were screened. Patients eligible for inclusion had CAP caused by either S. pneumoniae (pneuCAP) or due to another well-defined pathogen (otherCAP). Serotype-specific pneumococcal antibody concentrations (total IgG and IgG2/IgG1) before and 3-4weeks after PCV13 administration were measured (Luminex) and compared between pneuCAP and otherCAP patients. RESULTS: We vaccinated 60 patients:i.e. 34 pneuCAP and 26 otherCAP patients. In the pneuCAP group, 74% of patients were categorized as good responders (≥9/13 serotypes with concentration≥1300ng/ml), versus 77% in the otherCAP group. Significantly fewer full responders (i.e. 13/13 serotypes with a concentration≥1300ng/mL) were identified in the pneuCAP group (15% vs 42% respectively, p=0.02). For serotype 1, total IgG and IgG2/IgG1 subset post-vaccination concentrations were significantly lower among pneuCAP patients. Our additional case-series showed that of 16 pneuCAP patients who were infected by a serotype included in PCV13 three patients did not respond against the serotype originally responsible for their CAP episode, including one former bacteraemic pneumococcal CAP patient who also failed to show a response against the serotype responsible for CAP during infection. Thirteen patients did respond to the previously infecting serotype following PCV13 including three patients who had bacteraemic pneumococcal pneumonia and did not show a response during infection against the serotype responsible for CAP. CONCLUSIONS: Our results confirm the immunogenic properties of PCV13 in former pneumococcal CAP patients including patients previously regarded as potential hyporesponders. A slightly diminished overall humoral response to polysaccharides characterizes the former pneumococcal CAP patients. ClinicalTrials.gov Identifier: NCT02141009.

Randomized clinical trial of extended versus single-dose perioperative antibiotic prophylaxis for acute calculous cholecystitis.

BACKGROUND: Many patients who have surgery for acute cholecystitis receive postoperative antibiotic prophylaxis, with the intent to reduce infectious complications. There is, however, no evidence that extending antibiotics beyond a single perioperative dose is advantageous. This study aimed to determine the effect of extended antibiotic prophylaxis on infectious complications in patients with mild acute cholecystitis undergoing cholecystectomy. METHODS: For this randomized controlled non-inferiority trial, adult patients with mild acute calculous cholecystitis undergoing cholecystectomy at six major teaching hospitals in the Netherlands, between April 2012 and September 2014, were assessed for eligibility. Patients were randomized to either a single preoperative dose of cefazolin (2000 mg), or antibiotic prophylaxis for 3 days after surgery (intravenous cefuroxime 750 mg plus metronidazole 500 mg, three times daily), in addition to the single dose. The primary endpoint was rate of infectious complications within 30 days after operation. RESULTS: In the intention-to-treat analysis, three of 77 patients (4 per cent) in the extended antibiotic group and three of 73 (4 per cent) in the standard prophylaxis group developed postoperative infectious complications (absolute difference 0·2 (95 per cent c.i. -8·2 to 8·9) per cent). Based on a margin of 5 per cent, non-inferiority of standard prophylaxis compared with extended prophylaxis was not proven. Median length of hospital stay was 3 days in the extended antibiotic group and 1 day in the standard prophylaxis group. CONCLUSION: Standard single-dose antibiotic prophylaxis did not lead to an increase in postoperative infectious complications in patients with mild acute cholecystitis undergoing cholecystectomy. Registration number: NTR3089 (www.trialregister.nl).

[Is a salt-restricted diet now up for discussion?] / Staat zoutbeperking nu ter discussie?

A recent meta-analysis published in The Lancet related sodium excretion to mortality in both hypertensive and normotensive subjects. High salt excretion, measured in a spot urine test, was related to increased mortality in hypertensive subjects only, whereas low sodium excretion was related to increased mortality in both hypertensive and normotensive subjects. Here we discuss practical consequences of this analysis. The data underline the importance of salt restriction in hypertension; the analysis also shows that there is a lower limit to salt restriction. Since salt intake cannot be assessed adequately from the sodium content of a single urine sample, 24-hour urine collection is advised in subjects on a salt-restricted diet. A 24-hour urine collection allows checking for unnecessarily strict salt restriction or, as will more often be the case, shows the patient that adequate salt restriction has not yet been attained.

A Randomised Controlled Trial of Consent Procedures for the Use of Residual Tissues for Medical Research: Preferences of and Implications for Patients, Research and Clinical Practice.

BACKGROUND: Despite much debate, there is little evidence on consequences of consent procedures for residual tissue use. Here, we investigated these consequences for the availability of residual tissue for medical research, clinical practice, and patient informedness. METHODS: We conducted a randomised clinical trial with three arms in six hospitals. Participants, patients from whom tissue had been removed for diagnosis or treatment, were randomised to one of three arms: informed consent, an opt-out procedure with active information provision (opt-out plus), and an opt-out procedure without active information provision. Participants received a questionnaire six weeks post-intervention; a subsample of respondents was interviewed. Health care providers completed a pre- and post-intervention questionnaire. We assessed percentage of residual tissue samples available for medical research, and patient and health care provider satisfaction and preference. Health care providers and outcome assessors could not be blinded. RESULTS: We randomised 1,319 patients, 440 in the informed consent, 434 in the opt-out plus, and 445 in the opt-out arm; respectively 60.7%, 100%, and 99.8% of patients' tissue samples could be used for medical research. Of the questionnaire respondents (N = 224, 207, and 214 in the informed consent, opt-out plus, and opt-out arms), 71%, 69%, and 31%, respectively, indicated being (very) well informed. By questionnaire, the majority (53%) indicated a preference for informed consent, whereas by interview, most indicated a preference for opt-out plus (37%). Health care providers (N = 35) were more likely to be (very) satisfied with opt-out plus than with informed consent (p = 0.002) or opt-out (p = 0.039); the majority (66%) preferred opt-out plus. CONCLUSION: We conclude that opt-out with information (opt-out plus) is the best choice to balance the consequences for medical research, patients, and clinical practice, and is therefore the most optimal consent procedure for residual tissue use in Dutch hospitals. TRIAL REGISTRATION: Dutch Trial Register NTR2982.

Chlamydia psittaci: a relevant cause of community-acquired pneumonia in two Dutch hospitals.

BACKGROUND: Of all hospitalised community-acquired pneumonias (CAPs) only a few are known to be caused by Chlamydia psittaci. Most likely the reported incidence, ranging from of 0% to 2.1%, is an underestimation of the real incidence, since detection of psittacosis is frequently not incorporated in the routine microbiological diagnostics in CAP or serological methods are used. METHODS: C. psittaci real-time polymerase chain reaction (PCR) was routinely performed on the sputum of 147 patients hospitalised with CAP, who participated in a clinical trial conducted in two Dutch hospitals. In 119/147 patients the paired complement fixation test (CFT) was also performed for the presence of Chlamydia antibodies. Positive CFTs were investigated by micro- Immunofluorescence for psittacosis specificity. Case criteria for psittacosis were a positive PCR or a fourfold rise of antibody titre in CFT confirmed by micro- Immunofluorescence. Furthermore, we searched for parameters that could discriminate psittacosis from CAPs with other aetiology. RESULTS: 7/147 (4.8%) patients were diagnosed with psittacosis: six with PCR and one patient with a negative PCR, but with CFT confirmed by micro- Immunofluorescence. Psittacosis patients had had a higher temperature (median 39.6 vs. 38.2 °C;) but lower white blood cell count (median 7.4 vs. 13.7 x 109/l) on admission compared with other CAP patients. CONCLUSION: In this study, C. psittaci as CAP-causing pathogen was much higher than previously reported. To detect psittacosis, PCR was performed on all CAP patients for whom a sputum sample was available. For clinical use, PCR is a fast method and sputum availability allows genotyping; additional serology can optimise epidemiological investigations.

An undetected common renal arterial trunk: surgical consequences and morbidity analysis.

We present a patient with a recurrent precaval left renal artery, stemming from a right-sided common trunk renal artery. The patient was a 44-year male who presented with a post-traumatic grade IV renal injury. After 3 months without renal function improvement and repeated urinary tract infection, a laparoscopic nephrectomy of the affected right kidney was performed, without upfront identification of the vascular variation, resulting in ischemia of the remaining left kidney. An anastomosis of the common renal trunk and the distal left renal artery was created in between the abdominal aorta and the inferior vena cava. This case describes the importance of upfront detection of renal vascular variations using the appropriate imaging techniques.

The impact of renal function on platelet reactivity and clinical outcome in patients undergoing percutaneous coronary intervention with stenting.

Patients with chronic kidney disease (CKD) have an increased risk of cardiovascular disease. Previous studies have suggested that patients with CKD have less therapeutic benefit of antiplatelet therapy. However, the relation between renal function and platelet reactivity is still under debate. On-treatment platelet reactivity was determined in parallel by ADP- and AA-induced light transmittance aggregometry (LTA) and the VerifyNow® System (P2Y12 and Aspirin) in 988 patients on dual antiplatelet therapy, undergoing elective coronary stenting. Patients were divided into two groups according to the presence or absence of moderate/severe CKD (GFR<60 ml/min/1.73 m²). Furthermore, the incidence of all-cause death, non-fatal acute myocardial infarction, stent thrombosis and stroke at one-year was evaluated. Patients with CKD (n=180) had significantly higher platelet reactivity, regardless of the platelet function test used. Patients with CKD more frequently had high on-clopidogrel platelet reactivity (HCPR) and high on-aspirin platelet reactivity (HAPR) regardless of the platelet function test used. After adjustment for potential confounders, this was no longer significant. The event-rate was the highest in patients with both high on-treatment platelet reactivity (HPR) and CKD compared to those with neither high on-treatment platelet reactivity nor CKD. In conclusion, the magnitude of platelet reactivity as well as the incidence of HPR was higher in patients with CKD. However, since the incidence of HPR was similar after adjustment, a higher rate of co-morbidities in patients with CKD might be the major cause for this observation rather than CKD itself. CKD-patients with HCPR were at the highest risk of long-term cardiovascular events.

Direct haemodynamic effects of pulmonary arteriovenous malformation embolisation.

BACKGROUND: Transcatheter embolisation is widely used to close pulmonary arteriovenous malformations (PAVMs) in patients with hereditary haemorrhagic telangiectasia (HHT). Data on the direct cardiovascular haemodynamic changes induced by this treatment are scarce. OBJECTIVES: We investigated the direct haemodynamic effects of transcatheter embolisation of PAVMs, using non-invasive finger pressure measurements. METHODS: During the procedure, blood pressure, heart rate (HR), stroke volume (SV), cardiac output (CO), total peripheral resistance (TPR) and delta pressure/delta time (dP/dt) were continuously monitored using a Finometer®. Potential changes in these haemodynamic parameters were calculated from the pressure registrations using Modelflow® methodology. Absolute and relative changes were calculated and compared using the paired sample t-test. RESULTS: The present study includes 29 HHT patients (mean age 39 ± 15 years, 11 men) who underwent transcatheter embolotherapy of PAVMs. The total number of embolisations was 72 (mean per patient 2.5). Directly after PAVM closure, SV and CO decreased significantly by -11.9 % (p = 0.01) and -9.5 % (p = 0.01) respectively, without a significant change in HR (1.8 %). Mean arterial blood pressure increased by 4.1 % (p = 0.02), while the TPR and dP/dt did not increase significantly (5.8 % and 0.2 %, respectively). CONCLUSIONS: Significant haemodynamic changes occur directly after transcatheter embolisation of PAVMs, amongst which a decrease in stroke volume and cardiac output are most important.

Treatment with anti-inflammatory drugs in community-acquired pneumonia.

Pneumonia exhibits a broad range of severity, from mildly symptomatic at one end to fulminant septic shock and death at the other. Although an adequate inflammatory response is necessary for the clearance of microorganisms, excessive inflammation can lead to ongoing local and systemic damage. Because of this extended inflammatory response despite appropriate antibiotic therapy, as well as increasing antibiotic resistance, adjuvant therapy for pneumonia that can favourably modify the immune response has become an increasingly relevant approach to improve prognosis. Different adjuvant treatment options for pneumonia have recently been proposed. Promising treatment options include corticosteroids, statins, macrolides and Toll-like receptor antagonists. The aim of this review is to summarize the inflammatory response during pneumonia and discuss the current knowledge and future perspectives regarding the anti-inflammatory treatment options for patients with pneumonia.

Lagrangian statistics and flow topology in forced two-dimensional turbulence.

A study of the relationship between Lagrangian statistics and flow topology in fluid turbulence is presented. The topology is characterized using the Weiss criterion, which provides a conceptually simple tool to partition the flow into topologically different regions: elliptic (vortex dominated), hyperbolic (deformation dominated), and intermediate (turbulent background). The flow corresponds to forced two-dimensional Navier-Stokes turbulence in doubly periodic and circular bounded domains, the latter with no-slip boundary conditions. In the double periodic domain, the probability density function (pdf) of the Weiss field exhibits a negative skewness consistent with the fact that in periodic domains the flow is dominated by coherent vortex structures. On the other hand, in the circular domain, the elliptic and hyperbolic regions seem to be statistically similar. We follow a Lagrangian approach and obtain the statistics by tracking large ensembles of passively advected tracers. The pdfs of residence time in the topologically different regions are computed introducing the Lagrangian Weiss field, i.e., the Weiss field computed along the particles' trajectories. In elliptic and hyperbolic regions, the pdfs of the residence time have self-similar algebraic decaying tails. In contrast, in the intermediate regions the pdf has exponential decaying tails. The conditional pdfs (with respect to the flow topology) of the Lagrangian velocity exhibit Gaussian-like behavior in the periodic and in the bounded domains. In contrast to the freely decaying turbulence case, the conditional pdfs of the Lagrangian acceleration in forced turbulence show a comparable level of intermittency in both the periodic and the bounded domains. The conditional pdfs of the Lagrangian curvature are characterized, in all cases, by self-similar power-law behavior with a decay exponent of order -2.

Origin of lagrangian intermittency in drift-wave turbulence.

The Lagrangian velocity statistics of dissipative drift-wave turbulence are investigated. For large values of the adiabaticity (or small collisionality), the probability density function of the Lagrangian acceleration shows exponential tails, as opposed to the stretched exponential or algebraic tails, generally observed for the highly intermittent acceleration of Navier-Stokes turbulence. This exponential distribution is shown to be a robust feature independent of the Reynolds number. For small adiabaticity, algebraic tails are observed, suggesting the strong influence of point-vortex-like dynamics on the acceleration. A causal connection is found between the shape of the probability density function and the autocorrelation of the norm of the acceleration.

Reintroduction of Riva-Rocci measurements to determine systolic blood pressure?

INTRODUCTION: In 1896, Riva-Rocci introduced the upper arm cuff to measure systolic blood pressure. In 1905, Nicolai Sergeivich Korotkoff added the auscultatory technique, allowing measurement of both systolic and diastolic blood pressure. Both methods have, to our knowledge, never been formally tested against each other. In this study, we want to fill this gap in history. METHODS: We measured systolic blood pressure by the Korotkoff sound technique and approximated the Riva-Rocci technique by measuring cuff pressure at the moment that the first pulsation became visible in Finapres readings, at the finger. This proxy of the Riva-Rocci technique allows an objective, offline, analysis. Measurements were performed simultaneously on the same arm in 57 subjects. RESULTS: Systolic blood pressure measured by the Korotkoff sound technique was 167+/-30 mmHg (mean +/-SD ). Systolic blood pressure according to the Riva-Rocci technique was 165+/-32 mmHg. The Riva-Rocci technique underestimated measurements with the Korotkoff technique by 1.8+/-4.4 mmHg (NS, p=0.79). CONCLUSION: Riva-Rocci measurements of systolic blood pressure may be as good as the traditionally used Korotkoff measurements.

Alcohol and arterial wave reflections in middle aged and elderly men.

BACKGROUND: Augmentation index (AIx) is a measure of arterial wave reflection, providing information on the workload of the heart. and is a possible marker for cardiovascular disease risk. The relation of alcohol consumption with cardiovascular disease (CVD) risk is U-shaped with a protective effect of moderate alcohol consumption. The relation of alcohol consumption level with AIx has not been widely investigated, which prompted this study of the relation of alcohol consumption with AIx in a population-based cohort of men aged 40-80 years. METHODS: Three hundred and seventy-four men (mean age 60.5 years) participated in this cross-sectional study. Alcohol consumption and smoking habits were determined through a validated questionnaire. Fasting blood samples were drawn and analyzed for glucose and lipid levels and AIx was estimated by radial applanation tonometry using the SphygmoCor Device. The resultant data were analyzed using linear regression models. RESULTS: Age, height, heart rate, blood pressure, packyears, current smoking, presence of CVD and hypertension were independently related to AIx. The relation of alcohol consumption with AIx was U-shaped, with a significantly lower AIx in the group drinking 4-8 glasses/week (difference = -2.91%, 95% CI [-5.65; -0.18]) relative to those drinking 0-3 glasses/week. Additional adjustment for current smoking did not change this relationship, but adjustment for pulse wave velocity attenuated the relation. CONCLUSIONS: In a population-based cohort of men aged 40-80 years the relation of alcohol consumption level with AIx was U-shaped, further expanding the evidence for vascular protective effects of moderate alcohol intake.

Determinants of augmentation index in young men: the ARYA study.

BACKGROUND: There is an increasing interest in the augmentation index (AIx), the proportion of the central pulse pressure resulting from peripheral arterial wave reflection, which has been related to cardiovascular disease risk and mortality. Most of the data on the AIx have been collected in patients with established cardiovascular disease. In contrast, data in the young are scarce. However, as AIx might be used to evaluate cardiovascular disease risk already at an early age, we aimed to study determinants of AIx in a population of healthy young men. MATERIALS AND METHODS: Three hundred and thirty males (mean age of 28 years) of the Atherosclerosis Risk in Young Adults study (ARYA-study) were studied in this cross sectional, population-based study. Anthropometrics and risk factors for cardiovascular disease were determined and AIx was estimated by radial applanation tonometry. The data were analysed using linear regression models. RESULTS: Augmentation index was associated with age, height (inverse), heart rate (inverse) and mean arterial pressure (positive). After adjustment for these determinants, smoking (beta = 0.31%/pack years, 95% CI [0.06; 0.55]) and LDL-cholesterol (beta = 1.28%/(mmol L(-1)), 95% CI [0.04; 2.51]) were statistically significant related to AIx. CONCLUSIONS: This study among young adult males shows that smoking and LDL-cholesterol are positively related to AIx. These findings support the view that AIx may be used as a marker for early vascular damage and cardiovascular disease risk.

Acute effects of peritoneal dialysis on hemodynamics.

OBJECTIVES: To investigate the acute hemodynamic effects of peritoneal dialysis (PD) using the noninvasive Portapres technique [TNO Biomedical Instrumentation (TNO BMI); Amsterdam, The Netherlands]. DESIGN AND METHODS: Blood pressure was measured in 21 consecutive patients on continuous ambulatory PD during a standard peritoneal permeability analysis (SPA). Blood pressure, stroke volume, cardiac output, and total peripheral resistance were recorded and calculated using continuous finger pressure recordings with Portapres and Modelflow software (TNO BMI). The SPA consists of four phases: (1) drainage of night dwell dialysate, (2) instillation of a rinsing solution (1.36% glucose), (3) drainage of rinsing solution, and (4) instillation of the test solution (3.86% glucose to which dextran 70 has been added). RESULTS: Both systolic blood pressure (SBP) (7 +/- 9 mmHg, p < 0.005) and diastolic blood pressure (DBP) (5 +/- 6 mmHg, p < 0.01) increased during phase 2. Systolic BP and DBP increased further during phase 4 (SBP 8 +/- 14 mmHg, p < 0.05; DBP 6 +/- 8 mmHg, p < 0.005). These BP increases were caused by a rise in total peripheral resistance of 10% +/- 18% (p< 0.05) during phase 1, and 15% +/- 21% (p < 0.005) during phase 2. CONCLUSIONS: Instillation and dwell of a dialysis solution during PD causes a rise in blood pressure. This is caused by an increase in total peripheral resistance. Factors influencing total peripheral resistance could be a direct mechanical effect of dialysate on mesenteric resistance vessels or a temperature-related effect.

Renal vascular changes in renal disease independent of hypertension.

INTRODUCTION: Cardiovascular disease is common in patients with renal disease, but little is known about the effect of renal disease and loss of renal function on vascular morphology. Intima proliferation of small renal arteries, which correlates with atherosclerosis in the aorta, is sometimes present in renal disease and has been shown to increase with age and hypertension. We studied the effect of chronic renal disease and renal function, independent of hypertension, on intima proliferation. METHODS: We retrospectively selected renal biopsies of subjects in whom a glomerular filtration rate (GFR) measurement with [(125)I] iothalamate had been performed. To separate the effects of renal disease and renal function, we selected biopsies from (A) normotensive controls undergoing nephrectomy because of renal carcinomas; (B) normotensive patients with renal disease and GFR > 90 ml/min; (C) normotensive patients with GFR 30-90 ml/min, and (D) hypertensive patients with a GFR < 90 ml/min. The area of the arteriolar lumen, intima, and media were measured. RESULTS: No significant changes from control subjects were observed in group B. Intima proliferation was observed when renal function declined (intima/total vessel surface ratio was 0.262 +/- 0.071 in group C, 0.192 +/- 0.032 in group A, and 0.205 +/- 0.035 in group B, P < 0.05). The intima proliferation was aggravated in patients with renal insufficiency and hypertension (0.333 +/- 0.121, P < 0.05). Media surface area was not different between groups. CONCLUSION: Renal disease with preserved GFR does not cause significant intima proliferation of small renal arteries. Loss of renal function is accompanied by intima proliferation, even in the absence of systemic hypertension.

Arterial stiffness as underlying mechanism of disagreement between an oscillometric blood pressure monitor and a sphygmomanometer.

Oscillometric blood pressure devices tend to overestimate systolic blood pressure and underestimate diastolic blood pressure compared with sphygmomanometers. Recent studies indicate that discrepancies in performance between these devices may differ between healthy and diabetic subjects. Arterial stiffness in diabetics could be the underlying factor explaining these differences. We studied differences between a Dinamap oscillometric blood pressure monitor and a random-zero sphygmomanometer in relation to arterial stiffness in 1808 healthy elderly subjects. The study was conducted within the Rotterdam Study, a population-based cohort study of subjects aged 55 years and older. Systolic and diastolic blood pressure differences between a Dinamap and a random-zero sphygmomanometer were related to arterial stiffness, as measured by carotid-femoral pulse wave velocity. Increased arterial stiffness was associated with higher systolic and diastolic blood pressure readings by the Dinamap compared with the random-zero sphygmomanometer, independent of age, gender, and average mean blood pressure level of both devices. The beta-coefficient (95% CI) was 0.25 (0.00 to 0.50) mm Hg/(m/s) for the systolic blood pressure difference and 0.35 (0.20 to 0.50) mm Hg/(m/s) for the diastolic blood pressure difference. The results indicate that a Dinamap oscillometric blood pressure device, in comparison to a random-zero sphygmomanometer, overestimates systolic and diastolic blood pressure readings in subjects with stiff arteries.