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Medical AI Inquiry: You was designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.  Labels: OBJECTIVE, METHODS, RESULTS. Meshes: Adult, Albuminuria, Autonomic Nervous System, Blood Pressure, Chromium Radioisotopes, Diabetes Mellitus, Type 1, Diabetic Neuropathies, Electrocardiography, Electrocardiography, Ambulatory, Female, Glomerular Filtration Rate, Heart Rate, Humans, Male, Middle Aged, Regression Analysis.
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Are autonomic dysfunction and urinary albumin excretion rate associated with an abnormal blood pressure pattern in normotensive normoalbuminuric type 1 diabetic patients? Context: To analyze the role of autonomic function and other possible factors associated with a blunted fall in nocturnal blood pressure. A total of 39 normotensive normnoalbuminuric type 1 diabetic patients were studied. Glomerular filtration rate (51Cr-EDTA technique), extracellular volume (51Cr-EDTA distribution volume), and urinary albumin excretion rate (UAER) (by radioimmunoassay) were measured. The subjects' 24-h ambulatory blood pressure and a 24-h electrocardiogram were recorded simultaneously Heart rate variability was calculated in the time domain for 24 h, in the frequency domain at night, at rest in the supine position, and during tilt. Patients were classified according to diastolic blood pressure (dBP) night/day ratio as dipper patients (< or =0.9) and nondipper patients (>0.9). Nondipper patients presented a higher low-frequency (LF) component (a sympathetic index) and higher LF/high-frequency (HF) ratio during sleep than dipper patients (0.29 +/- 0.12 vs. 0.19 +/- 0.10 normalized units [n.u.], P = 0.008; and 0.98 +/- 0.53 vs. 0.55 +/- 0.45 n.u., P = 0.007, respectively). At rest, the LF component in nondipper patients (0.38 +/- 0.13 n.u.) was higher than in dipper patients (0.27 +/- 0.12 n.u., P = 0.04). After the tilt, nondipper patients did not show an increase in the LF component (P = 0.32), but in dipper patients, the increase was significant (P = 0.001). In both groups, tilting promoted a decrease in the HF component (a parasympathetic index). In a stepwise multiple linear regression analysis, the LF component during sleep and the UAER accounted for 24% of the variability in the dBP night/day ratio.
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The predominance of sympathetic activity and increased levels of UAER, although within the normal range, are associated with a blunted fall in nocturnal dBP in normoalbuminuric normotensive type 1 diabetic patients. Final Decision: yes