Exercise versus overnight albumin excretion rates in subjects with type 1 diabetes

Evidence-based risk assessment and recommendations for physical activity clearance: diabetes mellitus and related comorbidities1This paper is one of a selection of papers published in this Special Issue, entitled Evidence-based risk assessment and recommendations for physical activity clearance, and has undergone the Journal’s usual peer review process

Physical activity (PA) is one of the most powerful treatment options for persons with prediabetes or diabetes. However, some elevation in risk occurs with increased PA, at least initially, and certain precautions need to be made to lower these risks, particularly if these persons are unaccustomed to exercise. We conducted a standardized search of all adverse events associated with increased PA in persons with prediabetes or diabetes (type 1 or type 2) and provided evidence-based guidelines on PA screening in these apparently high-risk individuals. A systematic literature review was performed of all studies reporting on adverse events in persons with prediabetes or diabetes. Studies included were from all designs (retrospective and prospective including randomized controlled trials) and were assessed according to evaluation criteria adapted by a consensus panel. A total of 47 studies, involving >8000 individuals, were deemed eligible. A number of these studies identified a range of mild to severe acute risks with exercise (musculoskeletal injury, hypoglycemia, foot ulceration, proliferative retinopathy, hypotension, sudden death) but the overall prevalence was low. Based on several randomized controlled trials and prospective studies in which prescribed exercise was performed at a wide range of intensities, it appears that increased PA is a relatively safe procedure with no evidence of a loss of life. Based on our assessment of the available literature, we provide a new PA risk algorithm for persons with prediabetes and diabetes and comment on the role of the patient, the qualified exercise professional, and the patient’s physician in the risk screening process.

Current issues in measurement and reporting of urinary albumin excretion

BACKGROUND

Urinary excretion of albumin indicates kidney damage and is recognized as a risk factor for progression of kidney disease and cardiovascular disease. The role of urinary albumin measurements has focused attention on the clinical need for accurate and clearly reported results. The National Kidney Disease Education Program and the IFCC convened a conference to assess the current state of preanalytical, analytical, and postanalytical issues affecting urine albumin measurements and to identify areas needing improvement.

CONTENT

The chemistry of albumin in urine is incompletely understood. Current guidelines recommend the use of the albumin/creatinine ratio (ACR) as a surrogate for the error-prone collection of timed urine samples. Although ACR results are affected by patient preparation and time of day of sample collection, neither is standardized. Considerable intermethod differences have been reported for both albumin and creatinine measurement, but trueness is unknown because there are no reference measurement procedures for albumin and no reference materials for either analyte in urine. The recommended reference intervals for the ACR do not take into account the large intergroup differences in creatinine excretion (e.g., related to differences in age, sex, and ethnicity) nor the continuous increase in risk related to albumin excretion.

DISCUSSION

Clinical needs have been identified for standardization of (a) urine collection methods, (b) urine albumin and creatinine measurements based on a complete reference system, (c) reporting of test results, and (d) reference intervals for the ACR.

Stress tolerance test and SDS-PAGE for the analysis of urinary proteins in children and youths

Excretion of urinary proteins (UP) is an important marker for the evaluation of patients with progressive renal disease. In order to analyze quantitative and qualitative variability of UP in relation to physical activity, we used standardized stress tolerance test and SDS-PAGE. Five urine samples were obtained from each patient at rest, during ordinary daily activity and after physical stress. Determination of total proteins was performed using Meulman's classic method with sulfosalicylic acid. UP were separated by ultrathin horizontal gradient SDS-PAGE according to Görg. There were 142 patients; 40 with poststreptococcal glomerulonephritis (PSGN), 11 with diabetes mellitus, 16 with chronic pyelonephritis and 75 who attended for investigation of asymptomatic proteinuria. Functional proteinuria was established in 42 subjects, who displayed maximal UP excretion during stress and the presence of apolipoprotein AI on SDS-PAGE. Children with PSGN showed no significant increase of UP during stress. Some children with diabetes mellitus (27%) and chronic pyelonephritis (47%) displayed microproteinuria or overt proteinuria after stress. Quantitative and qualitative changes in total UP excretion can be detected by stress tolerance test and SDS-PAGE. It remains to be seen whether stress tolerance test can identify children and youths who are at higher risk for disease progression.