Renal tissue oxygenation in essential hypertension and chronic kidney disease

Animal studies suggest that renal tissue hypoxia plays an important role in the development of renal damage in hypertension and renal diseases, yet human data were scarce due to the lack of noninvasive methods. Over the last decade, blood oxygenation level-dependent magnetic resonance imaging (BOLD-MRI), detecting deoxyhemoglobin in hypoxic renal tissue, has become a powerful tool to assess kidney oxygenation noninvasively in humans. This paper provides an overview of BOLD-MRI studies performed in patients suffering from essential hypertension or chronic kidney disease (CKD). In line with animal studies, acute changes in cortical and medullary oxygenation have been observed after the administration of medication (furosemide, blockers of the renin-angiotensin system) or alterations in sodium intake in these patient groups, underlining the important role of renal sodium handling in kidney oxygenation. In contrast, no BOLD-MRI studies have convincingly demonstrated that renal oxygenation is chronically reduced in essential hypertension or in CKD or chronically altered after long-term medication intake. More studies are required to clarify this discrepancy and to further unravel the role of renal oxygenation in the development and progression of essential hypertension and CKD in humans.

Myocardial infarction and post-traumatic stress disorder: frequency, outcome, and atherosclerotic mechanisms

BACKGROUND: Post-traumatic stress disorder (PTSD) may develop in the aftermath of an acute myocardial infarction (MI). Whether PTSD is a risk factor for cardiovascular disease (CVD) is elusive. The biological mechanisms linking PTSD with atherosclerosis are unclear. DESIGN: A critical review of 31 studies in the English language pursuing three aims: (i) to estimate the prevalence of PTSD in post-MI patients; (ii) to investigate the association of PTSD with cardiovascular endpoints; and (iii) to search for low-grade systemic inflammatory changes in PTSD pertinent to atherosclerosis. METHODS: We located studies by PubMed electronic library search and through checking the bibliographies of these sources. RESULTS: The weighted prevalence of PTSD after MI was 14.7% (range 0-25%; a total of 13 studies and 827 post-MI patients). Two studies reported a prospective association between PTSD and an increased risk of cardiovascular readmission in post-MI patients and of cardiovascular mortality in combat veterans, respectively. In a total of 11 studies, patients with PTSD had increased rates of physician-rated and self-reported cardiovascular diseases. Various cytokines and C-reactive protein were investigated in a total of seven studies suggesting that PTSD confers a pro-inflammatory state. CONCLUSIONS: Increasing evidence suggests that PTSD specifically related to MI develops considerably frequently in post-MI patients. More research is needed in larger cohorts applying a population design to substantiate findings suggesting PTSD is an atherogenic risk factor and to understand better the suspected behavioural and biological mechanisms involved.

Geriatric Pain Measure short form: development and initial evaluation

OBJECTIVES: To develop and evaluate a short form of the 24-item Geriatric Pain Measure (GPM) for use in community-dwelling older adults. DESIGN: Derivation and validation of a 12-item version of the GPM in a European and an independent U.S. sample of community-dwelling older adults. SETTING: Three community-dwelling sites in London, United Kingdom; Hamburg, Germany; Solothurn, Switzerland; and two ambulatory geriatrics clinics in Los Angeles, California. PARTICIPANTS: European sample: 1,059 community-dwelling older persons from three sites (London, UK; Hamburg, Germany; Solothurn, Switzerland); validation sample: 50 persons from Los Angeles, California, ambulatory geriatric clinics. MEASUREMENTS: Multidimensional questionnaire including self-reported demographic and clinical information. RESULTS: Based on item-to-total scale correlations in the European sample, 11 of 24 GPM items were selected for inclusion in the short form. One additional item (pain-related sleep problems) was included based on clinical relevance. In the validation sample, the Cronbach alpha of GPM-12 was 0.92 (individual subscale range 0.77-0.92), and the Pearson correlation coefficient (r) between GPM-12 and the original GPM was 0.98. The correlation between the GPM-12 and the McGill Pain Questionnaire was 0.63 (P<.001), similar to the correlation between the original GPM and the McGill Pain Questionnaire (Pearson r=0.63; P<.001). Exploratory factor analysis indicated that the GPM-12 covers three subfactors (pain intensity, pain with ambulation, disengagement because of pain). CONCLUSION: The GPM-12 demonstrated good validity and reliability in these European and U.S. populations of older adults. Despite its brevity, the GPM-12 captures the multidimensional nature of pain in three subscales. The self-administered GPM-12 may be useful in the clinical assessment process and management of pain and in pain-related research in older persons.