9 resultados para ambulatory monitoring
em BORIS: Bern Open Repository and Information System - Berna - Suiça
Resumo:
BACKGROUND: Although affective instability is an essential criterion for borderline personality disorder (BPD), it has rarely been reported as an outcome criterion. To date, most of the studies assessing state affective instability in BPD using paper-pencil diaries did not find indications of this characteristic, whereas in others studies, the findings were conflicting. Furthermore, the pattern of instability that characterizes BPD has not yet been identified. METHOD: We assessed the affective states of 50 female patients with BPD and 50 female healthy controls (HC) during 24 hours of their everyday life using electronic diaries. RESULTS: In contrast to previous paper-and-pencil diary studies, heightened affective instability for both emotional valence and distress was clearly exhibited in the BPD group but not in the HC group. Inconsistencies in previous papers can be explained by the methods used to calculate instability (see Appendix). In additional, we were able to identify a group-specific pattern of instability in the BPD group characterized by sudden large decreases from positive mood states. Furthermore, 48% of the declines from a very positive mood state in BPD were so large that they reached a negative mood state. This was the case in only 9% of the HC group, suggesting that BPD patients, on average, take less time to fluctuate from a very positive mood state to a negative mood state. CONCLUSION: Future ambulatory monitoring studies will be useful in clarifying which events lead to the reported, sudden decrease in positive mood in BPD patients.
Resumo:
Many experts now believe that pervasive problems in affect regulation constitute the central area of dysfunction in borderline personality disorder (BPD). However, data is sparse and inconclusive. We hypothesized that patients with BPD, in contrast to healthy gender and nationality-matched controls, show a higher frequency and intensity of self-reported emotions, altered physiological indices of emotions, more complex emotions and greater problems in identifying specific emotions. We took a 24-hour psychophysiological ambulatory monitoring approach to investigate affect regulation during everyday life in 50 patients with BPD and in 50 healthy controls. To provide a typical and unmanipulated sample, we included only patients who were currently in treatment and did not alter their medication schedule. BPD patients reported more negative emotions, fewer positive emotions, and a greater intensity of negative emotions. A subgroup of non-medicated BPD patients manifested higher values of additional heart rate. Additional heart rate is that part of a heart rate increase that does not directly result from metabolic activity, and is used as an indicator of emotional reactivity. Borderline participants were more likely to report the concurrent presence of more than one emotion, and those patients who just started treatment in particular had greater problems in identifying specific emotions. Our findings during naturalistic ambulatory assessment support emotional dysregulation in BPD as defined by the biosocial theory of [Linehan, M.M., 1993. Cognitive-Behavioral Treatment of Borderline Personality Disorder. The Guildford Press, New York.] and suggest the potential utility for evaluating treatment outcome.
Resumo:
Approximate entropy (ApEn) of blood pressure (BP) can be easily measured based on software analysing 24-h ambulatory BP monitoring (ABPM), but the clinical value of this measure is unknown. In a prospective study we investigated whether ApEn of BP predicts, in addition to average and variability of BP, the risk of hypertensive crisis. In 57 patients with known hypertension we measured ApEn, average and variability of systolic and diastolic BP based on 24-h ABPM. Eight of these fifty-seven patients developed hypertensive crisis during follow-up (mean follow-up duration 726 days). In bivariate regression analysis, ApEn of systolic BP (P<0.01), average of systolic BP (P=0.02) and average of diastolic BP (P=0.03) were significant predictors of hypertensive crisis. The incidence rate ratio of hypertensive crisis was 14.0 (95% confidence interval (CI) 1.8, 631.5; P<0.01) for high ApEn of systolic BP as compared to low values. In multivariable regression analysis, ApEn of systolic (P=0.01) and average of diastolic BP (P<0.01) were independent predictors of hypertensive crisis. A combination of these two measures had a positive predictive value of 75%, and a negative predictive value of 91%, respectively. ApEn, combined with other measures of 24-h ABPM, is a potentially powerful predictor of hypertensive crisis. If confirmed in independent samples, these findings have major clinical implications since measures predicting the risk of hypertensive crisis define patients requiring intensive follow-up and intensified therapy.
Resumo:
INTRODUCTION: Voluntary muscle activity, including swallowing, decreases during the night. The association between nocturnal awakenings and swallowing activity is under-researched with limited information on the frequency of swallows during awake and asleep periods. AIM: The aim of this study was to assess nocturnal swallowing activity and identify a cut-off predicting awake and asleep periods. METHODS: Patients undergoing impedance-pH monitoring as part of GERD work-up were asked to wear a wrist activity detecting device (Actigraph(®)) at night. Swallowing activity was quantified by analysing impedance changes in the proximal esophagus. Awake and asleep periods were determined using a validated scoring system (Sadeh algorithm). Receiver operating characteristics (ROC) analyses were performed to determine sensitivity, specificity and accuracy of swallowing frequency to identify awake and asleep periods. RESULTS: Data from 76 patients (28 male, 48 female; mean age 56 ± 15 years) were included in the analysis. The ROC analysis found that 0.33 sw/min (i.e. one swallow every 3 min) had the optimal sensitivity (78 %) and specificity (76 %) to differentiate awake from asleep periods. A swallowing frequency of 0.25 sw/min (i.e. one swallow every 4 min) was 93 % sensitive and 57 % specific to identify awake periods. A swallowing frequency of 1 sw/min was 20 % sensitive but 96 % specific in identifying awake periods. Impedance-pH monitoring detects differences in swallowing activity during awake and asleep periods. Swallowing frequency noticed during ambulatory impedance-pH monitoring can predict the state of consciousness during nocturnal periods
Resumo:
Introduction: Diagnosing arrhythmias by conventional Holter-ECG can be cumbersome because of artifacts, skin irritation and poor P-waves. In contrast, esophageal electrocardiography (eECG) is promising due to the anatomic relationship of the esophagus to the atria and its favorable bioelectric properties. Methods used: In an ambulant setting, we recorded eECGs from 10 volunteers with a novel, highly-miniaturized eECG recorder that is worn discretely behind the ear (1.5×1.8×5cm, 22grams). The device continuously records two eECG leads during 3 days with 500Hz sampling frequency and 24-bit resolution. Results: Mean ± SD recording time was 21.7±19.6 hours (max. 60 hours). Test persons were not limited in daily activities (e.g. eating, speaking) and only complained mild discomfort during probe insertion, which subsided later on. During 99.8% of time, the recorder acquired signals appropriate for further analysis. In unfiltered data, QRS complexes and P-waves were identifiable during >98% of time. P waves had higher amplitudes as compared to surface ECG (0.71 ± 0.42mV vs. 0.16 ± 0.03mV, p = 0.004). No complications occurred. Conclusion: Ambulatory eECG recording is safe, well tolerated and promising due to excellent P-wave detection, overcoming some limitations of conventional Holter ECG.
Resumo:
OBJECTIVE Little information is available on the early course of hypertension in type 1 diabetes. The aim of our study, therefore, was to document circadian blood pressure profiles in patients with a diabetes duration of up to 20 years and relate daytime and nighttime blood pressure to duration of diabetes, BMI, insulin therapy, and HbA1c. RESEARCH DESIGN AND METHODS Ambulatory profiles of 24-h blood pressure were recorded in 354 pediatric patients with type 1 diabetes (age 14.6 +/- 4.2 years, duration of diabetes 5.6 +/- 5.0 years, follow-up for up to 9 years). A total of 1,011 profiles were available for analysis from patients not receiving antihypertensive medication. RESULTS Although daytime mean systolic pressure was significantly elevated in diabetic subjects (+3.1 mmHg; P < 0.0001), daytime diastolic pressure was not different from from the height- and sex-adjusted normal range (+0.1 mmHg, NS). In contrast, both systolic and diastolic nighttime values were clearly elevated (+7.2 and +4.2 mmHg; P < 0.0001), and nocturnal dipping was reduced (P < 0.0001). Systolic blood pressure was related to overweight in all patients, while diastolic blood pressure was related to metabolic control in young adults. Blood pressure variability was significantly lower in girls compared with boys (P < 0.01). During follow-up, no increase of blood pressure was noted; however, diastolic nocturnal dipping decreased significantly (P < 0.03). Mean daytime blood pressure was significantly related to office blood pressure (r = +0.54 for systolic and r = +0.40 for diastolic pressure); however, hypertension was confirmed by ambulatory blood pressure measurement in only 32% of patients with elevated office blood pressure. CONCLUSIONS During the early course of type 1 diabetes, daytime blood pressure is higher compared with that of healthy control subjects. The elevation of nocturnal values is even more pronounced and nocturnal dipping is reduced. The frequency of white-coat hypertension is high among adolescents with diabetes, and ambulatory blood pressure monitoring avoids unnecessary antihypertensive treatment.
Resumo:
OBJECTIVE Altered arterial stiffness is a recognized risk factor of poor cardiovascular health. Ambulatory arterial stiffness index (AASI, defined as one minus the regression slope of diastolic on systolic blood pressure values derived from a 24 h arterial blood pressure monitoring, ABPM) is an upcoming and readily available marker of arterial stiffness. Our hypothesis was that AASI is increased in obese children compared to age- and gender matched healthy subjects. METHODS AASI was calculated from ABPM in 101 obese children (BMI ≥ 1.88 SDS according to age- and sex-specific BMI charts), 45% girls, median BMI SDS 2.8 (interquartile range (IQR) 2.5-3.4), median age 11.5 years (9.1-13.4) and compared with an age and gender matched healthy control group of 71 subjects with median BMI SDS 0.0 (-0.8-0.5). Multivariate regression analysis was applied to identify significant independent factors explaining AASI variability in this population. RESULTS AASI was significantly higher in obese children compared to controls (0.388 (0.254-0.499) versus 0.190 (0.070-0.320), p < 0.0001), but blood pressure values were similar. In a multivariate analysis including obese children only, AASI was independently predicted by 24-h systolic blood pressure SDS (p = 0.012); in a multivariate analysis including obese children and controls BMI SDS and pulse pressure independently influenced AASI (p < 0.001). CONCLUSIONS This study shows that AASI, a surrogate marker of arterial stiffness, is increased in obese children. AASI seems to be influenced by BMI and pulse pressure independently of systolic and diastolic blood pressure values, suggesting that other factors are involved in increased arterial stiffness in obese children.
Resumo:
Intake of caffeinated beverages might be associated with reduced cardiovascular mortality possibly via the lowering of blood pressure. We estimated the association of ambulatory blood pressure with urinary caffeine and caffeine metabolites in a population-based sample. Families were randomly selected from the general population of Swiss cities. Ambulatory blood pressure monitoring was conducted using validated devices. Urinary caffeine, paraxanthine, theophylline, and theobromine excretions were measured in 24 hours urine using ultrahigh performance liquid chromatography tandem mass spectrometry. We used mixed models to explore the associations of urinary excretions with blood pressure although adjusting for major confounders. The 836 participants (48.9% men) included in this analysis had mean age of 47.8 and mean 24-hour systolic and diastolic blood pressure of 120.1 and 78.0 mm Hg. For each doubling of caffeine excretion, 24-hour and night-time systolic blood pressure decreased by 0.642 and 1.107 mm Hg (both P values <0.040). Similar inverse associations were observed for paraxanthine and theophylline. Adjusted night-time systolic blood pressure in the first (lowest), second, third, and fourth (highest) quartile of paraxanthine urinary excretions were 110.3, 107.3, 107.3, and 105.1 mm Hg, respectively (P trend <0.05). No associations of urinary excretions with diastolic blood pressure were generally found, and theobromine excretion was not associated with blood pressure. Anti-hypertensive therapy, diabetes mellitus, and alcohol consumption modify the association of caffeine urinary excretion with systolic blood pressure. Ambulatory systolic blood pressure was inversely associated with urinary excretions of caffeine and other caffeine metabolites. Our results are compatible with a potential protective effect of caffeine on blood pressure.