Geriatric syndromes and functions in older adults with COVID-19 hospitalized in sub-acute care: a multicenter study.

OBJECTIVE: Alternatives to conventional acute hospitalizations have been particularly useful during the COVID-19 pandemic. However, little is known on the management and outcomes of COVID-19 in older patient admitted to non-acute settings. The main aim of this study was to determine the effect of geriatrics syndromes on functional outcomes in older COVID-19 patients cared in sub-acute units. METHODS: Prospective multicenter observational cohort study of patients aged 65 years and older with COVID-19, admitted to sub-acute units in Italy and Spain. Multivariable logistic regression models were used to test the association between geriatric syndromes and other clinical variables, and the functional status at discharge, defined by a Barthel Index > = 80. RESULTS: A total of 158 patients were included in the study with a median age of 82 [Interquartile Range 81, 83]; of these 102 (65%) patients had a Barthel Index ≥ 80 at discharge. In the main multivariable logistic regression model a higher severity of frailty-measured with the Clinical Frailty Scale-(OR 0.30; CI 0.18-0.47), and the presence of delirium (OR 0.04; CI 0.00-0.35) at admission were associated with lower odds of a higher functional status at discharge. Other variables associated with lower functional status were female gender (OR 0.36; CI 0.13-0.96), and a higher number of comorbidities (OR 0.48; CI 0.26-0.82). CONCLUSION: The study reports a relatively high prevalence of functional recovery for older COVID-19 patients admitted to sub-acute units. Additionally, it underlines the importance of targeting geriatrics syndromes, in particular frailty and delirium, for their possible effects on functional recovery.

Structural alterations in subcutaneous small resistance arteries predict changes in the renal function of hypertensive patients.

BACKGROUND: We have previously demonstrated that structural alterations in subcutaneous small resistance arteries of hypertensive patients, as indicated by an increased media to lumen ratio (M/L), are a potent predictor of cardiovascular events, and that a close correlation exists between serum creatinine and M/L. The aim of the present study was to assess whether M/L of subcutaneous small resistance arteries may predict subsequent changes in renal function in hypertensive patients. METHOD: Sixty participants (13 normotensive participants and 47 hypertensive patients) underwent a biopsy of subcutaneous fat. Resistance-sized arteries were dissected and mounted on a wire myograph, and M/L was measured. Patients were re-evaluated after a mean follow-up period of 8.6 years. Serum creatinine, blood urea nitrogen, and uric acid were measured; glomerular filtration rate (eGFR) was estimated according to Modification of Diet in Renal Disease formula. RESULTS: At baseline, we observed significant correlations between M/L and serum creatinine, eGFR, blood urea nitrogen, systolic, diastolic, mean, and pulse pressure. In addition, we observed significant correlations between M/L and serum creatinine at follow-up (r = 0.57; P < 0.001), percentage changes in serum creatinine (r = 0.46; P < 0.001), eGFR at follow-up (r = -0.43; P < 0.001); percentage changes in eGFR, yearly changes in eGFR, blood urea nitrogen at follow-up, and uric acid at follow-up. A multivariate analysis in which all common cardiovascular risk factors were included showed that M/L ratio is the most potent predictor of changes in renal function. CONCLUSION: Our data suggest that structural alterations in subcutaneous small arteries may predict the time course of changes in renal function during a follow-up period of about 9 years.

Effects of melatonin and Pycnogenol on small artery structure and function in spontaneously hypertensive rats.

It was suggested that oxidative stress has a key role in the development of endothelial dysfunction, as well as microvascular structural alterations. Therefore, we have investigated 2 substances with antioxidant properties: melatonin and Pycnogenol. We treated 7 spontaneously hypertensive rats (SHRs) with melatonin and 7 with Pycnogenol for 6 weeks. We compared results obtained with those observed in 7 SHRs and 7 Wistar-Kyoto normotensive control rats kept untreated. Mesenteric small resistance arteries were dissected and mounted on a wire myograph, and a concentration-response curve to acetylcholine was performed. Aortic contents of metalloproteinase 2, Bax, inducible NO synthase, and cyclooxygenase 2 were evaluated, together with the aortic content of total collagen and collagen subtypes and apoptosis rate. A small reduction in systolic blood pressure was observed. A significant improvement in mesenteric small resistance artery structure and endothelial function was observed in rats treated with Pycnogenol and melatonin. Total aortic collagen content was significantly greater in untreated SHRs compared with Wistar-Kyoto control rats, whereas a full normalization was observed in treated rats. Apoptosis rate was increased in the aortas of untreated SHRs compared with Wistar-Kyoto control rats; an even more pronounced increase was observed in treated rats. Bax and metalloproteinase 2 expressions changed accordingly. Cyclooxygenase 2 and inducible NO synthase were more expressed in the aortas of untreated SHRs compared with Wistar-Kyoto control rats; this pattern was normalized by both treatments. In conclusion, our data suggest that treatment with Pycnogenol and melatonin may protect the vasculature, partly independent of blood pressure reduction, probably through their antioxidant effects.

Vasodilator effects of red wines in subcutaneous small resistance artery of patients with essential hypertension.

BACKGROUND: It has been suggested that in animal models, red wine may have a protective effect on the vascular endothelium. However, it is not known whether this effect is also present in human small vessels and whether it is specific for certain wines. The objective of this study is to compare the vasodilator effects in subcutaneous small resistance arteries of wines with different flavonoid content as well as of ethanol vs. wines in normotensive (NT) subjects and in patients with essential hypertension (EH). METHODS: Twenty-six EH and 27 NT were included in the study. Subcutaneous small resistance arteries were dissected and mounted on a micromyograph. Then we evaluated vasodilator responses as concentration-response curves (20, 30, and 50 microl) to the following items: (i) a red wine produced in small oak barrels ("en barrique": EB) (Barolo Oberto 1994), (ii) a red wine produced in large wood barrels (LB) (Barolo Scarzello 1989), (iii) a red wine produced in steel tanks (Albarello Rosso del Salento 1997), and (iv) a white wine produced in steel tanks in the presence or absence of an inhibitor of the nitric oxide (NO) synthase (L-NMMA 100 micromol/l). RESULTS: A dose-dependent vasodilator effect of red wines (particularly EB and LB) was detected in both NT and HT. The observed response was not reduced after preincubation with L-NMMA. CONCLUSIONS: Our results suggest red wines are more potent vasodilator than ethanol alone, possibly depending on the content of polyphenols or tannic acid. HT show similar responses compared with NT, indicating that red wine is not harmful in this population.

Role of heme oxygenase in modulating endothelial function in mesenteric small resistance arteries of spontaneously hypertensive rats.

It has been proposed that endothelial dysfunction is due to the excessive degradation of nitric oxide (NO) by oxidative stress. The enzyme heme-oxygenase (HO) seems to exert a protective effect on oxidative stress in the vasculature, both in animal models and in humans. The objective of this study is to evaluate the effects of inhibition or activation of HO on endothelial function in mesenteric small resistance arteries of spontaneously hypertensive rats (SHR). Six SHR were treated with cobalt protoporphyrin IX 50 mg/Kg (CoPP), an activator of HO; six SHR with stannous mesoporphyrin 30 mg/Kg (SnMP), an inhibitor of HO, and six SHR with saline. As controls, six Wistar-Kyoto rats (WKY) were treated with CoPP, six WKY with SnMP, and six WKY with saline. Drugs were injected in the peritoneum once a week for 2 weeks. Systolic blood pressure (SBP) was measured (tail cuff method) before and after treatment. Mesenteric small resistance arteries were mounted on a micromyograph. Endothelial function was evaluated as a cumulative concentration-response curve to acetylcholine (ACH), before and after preincubation with N(G)-methyl-L-arginine (L-NMMA, inhibitor of NO synthase), and to bradykinin (BK). In SHR treatment with CoPP, improved ACH-and BK-induced vasodilatation (ANOVA p < 0.001) and this improvement was abolished by L-NMMA (ANOVA p < 0.001). SnMP was devoid of effects on endothelial function. In WKY, both activation and inhibition of HO did not substantially affect endothelium-mediated vasodilatation. The stimulation of HO seems to induce an improvement of endothelial dysfunction in SHR by possibly reducing oxidative stress and increasing NO availability.

Hypertrophic remodeling of subcutaneous small resistance arteries in patients with Cushing's syndrome.

OBJECTIVE: Structural alterations of small resistance arteries in essential hypertensive patients (EH) are mostly characterized by inward eutrophic remodeling. However, we observed hypertrophic remodeling in patients with renovascular hypertension, in those with acromegaly, as well as in patients with non-insulin-dependent diabetes mellitus, suggesting a relevant effect of humoral growth factors on vascular structure, even independent from the hemodynamic load. Cortisol may stimulate the renin-angiotensin system and may induce cardiac hypertrophy. However, presently no data are available about small artery structure in patients with Cushing's syndrome. SUBJECTS: We have investigated the structure of sc small resistance arteries in 12 normotensive subjects (NT), in 12 EH subjects, and in eight patients with Cushing's syndrome (CS). Small arteries from sc fat were dissected and mounted on a micromyograph. The normalized internal diameter, media thickness, media to lumen ratio, and the media cross-sectional area were measured, as well as indices of oxidative stress. RESULTS: Demographic variables were similar in the three groups, except for clinic blood pressure. The media to lumen ratio was significantly greater in EH and CS, compared with NT; no difference was observed between EH and CS. The media cross-sectional area was significantly greater in CS compared with EH and with NT. An increased vascular oxidative stress was present in CS, as demonstrated by increased levels of superoxide anions, cyclooxygenase-1 and endothelial nitric oxide synthase in the microvessels. CONCLUSION: Our results suggest the presence of hypertrophic remodeling in sc small resistance arteries of CS, probably as a consequence of growth-promoting properties of circulating cortisol and/or increased vascular oxidative stress.

Immunohistochemical evaluation of microvascular rarefaction in hypertensive humans and in spontaneously hypertensive rats.

OBJECTIVE: No data are presently available about changes in capillary density in the skeletal muscle and in the brain of spontaneously hypertensive rats (SHR) in relation to the development of hypertension. DESIGN AND METHODS: We have investigated 4 week-old and 12 week-old SHR and age-matched normotensive Wistar-Kyoto controls (WKY). Microvessel density (MVD) in the cerebral cortex and in a skeletal muscle were evaluated in sections stained for CD31. We also evaluated MVD in the dermal tissue of normotensive subjects and essential hypertensive patients. Subcutaneous small resistance arteries were dissected and mounted in a micromyograph and the media to lumen ratio (M/L) was measured. RESULTS: A significant reduction in MVD in the skeletal muscle and in the brain of SHR was clearly observed at 12 weeks of age, after the development of hypertension, but not at 4 weeks of age (pre-hypertensive condition). In hypertensive patients a significant reduction in the dermal MVD and an inverse correlation between M/L and MVD was observed. CONCLUSIONS: Our results suggest that, in the brain and skeletal muscle of adult SHR after the development of hypertension, and in the derma of adult essential hypertensive patients microvascular rarefaction may occur.

Altered structure of small cerebral arteries in patients with essential hypertension.

OBJECTIVE: Structural alterations in the microcirculation may be considered an important mechanism of organ damage. An increased media-to-lumen ratio of subcutaneous small resistance arteries has been demonstrated to predict the development of cardiocerebrovascular events in hypertensive patients. Alterations in the structure of small cerebral arteries have been demonstrated in animal models of experimental or genetic hypertension. However, no evaluation with reliable techniques has ever been performed in humans. DESIGN AND METHODS: Twenty-eight participants were included in the present study: they were 13 hypertensive patients and 15 normotensive individuals. All participants underwent a neurosurgical intervention for benign or malign tumors. A small portion of morphologically normal cerebral tissue was excised from surgical samples and examined. Cerebral small resistance arteries (relaxed diameter around 200 mum) were dissected and mounted on an isometric and isobaric myograph, and the tunica media to internal lumen ratio was measured. In addition, cerebral cortical microvessel density (MVD) was also evaluated. The tissue was sectioned and stained for CD31, and MVD was measured with an automated image analyzer (percentage of area stained). Blood pressure values were evaluated, before surgical intervention, by standard sphygmomanometry. RESULTS: M/L was significantly greater and MVD significantly lower in hypertensive patients than that in normotensive individuals. No difference between groups in collagen content or mechanical properties of cerebral small arteries was observed. CONCLUSION: Our results indicate that structural alterations of small cerebral vessels are present in hypertensive patients compared with normotensive individuals, similar to those previously observed in subcutaneous small arteries.

Determinants of the structure of resistance-sized arteries in hypertensive patients.

OBJECTIVE: It has been previously demonstrated that structural alterations of subcutaneous small resistance arteries of hypertensive patients, as indicated by an increased media to lumen (M/L) ratio, is the most potent predictor of cardiovascular events. The aim of the present study was to identify possible determinants of small resistance artery structure that may be evaluated with non-invasive approaches. MATERIALS AND METHODS: One hundred and ninety-nine subjects (normotensives, essential hypertensives and patients with secondary hypertension) were included in the present study. All subjects were submitted to a biopsy of subcutaneous fat from the gluteal or the anterior abdominal region. Small resistance arteries were dissected and mounted on an isometric myograph, and M/L ratio was measured. All patients underwent standard biochemical tests, clinic blood pressure measurement, standard echocardiography and 24-h ambulatory blood pressure measurement. Glomerular filtration rate (GFR) was calculated according to MDRD study formula and Cockroft's formula. RESULTS: Significant correlation was found between M/L ratio and, respectively: GFR calculated both with MDRD study formula and Cockroft-Gault formula, creatinine serum, blood urea nitrogen, glycaemia, circulating sodium, clinical pulse pressure, stroke volume to pulse pressure ratio, clinical systolic, diastolic and mean arterial pressure, daytime pulse pressure. However, in a multivariate regression analysis, only serum creatinine remained in the model, and proved to be an independent predictor of small artery structure. CONCLUSIONS: Indices of renal function and, probably, of large artery distensibility may be related to small arteries remodelling in hypertension.

Angiotensin receptor blockers improve insulin signaling and prevent microvascular rarefaction in the skeletal muscle of spontaneously hypertensive rats.

OBJECTIVE: Spontaneously hypertensive rats are an example of an animal model of genetic hypertension with insulin resistance. The aim of this study was to investigate insulin signaling in the heart and in the skeletal muscle of spontaneously hypertensive rats, as well as to evaluate the effects of renin-angiotensin system blockade. DESIGN AND METHODS: We investigated eight untreated spontaneously hypertensive rats of 12 weeks of age and eight age-matched normotensive Wistar-Kyoto controls. In addition, eight spontaneously hypertensive rats were treated for 8 weeks with the angiotensin receptor blocker olmesartan, and eight spontaneously hypertensive rats with the angiotensin-converting enzyme inhibitor enalapril. The heart and a skeletal muscle (quadriceps femoris) were promptly dissected and frozen. Insulin signaling was evaluated by Western blot analysis of involved proteins; in addition, microvessel density was indirectly evaluated by immunohistochemistry. RESULTS: Blood pressure values were normalized by both olmesartan and enalapril. In the heart, no statistically significant difference in the expression of proteins involved in insulin signaling was observed between untreated spontaneously hypertensive rats and Wistar-Kyoto controls. On the contrary, in the skeletal muscle of untreated spontaneously hypertensive rats, we noted a significant reduction of insulin receptors, of insulin-receptor substrate-1, and of phosphorylated-mammalian target of rapamycin. The treatment with olmesartan normalized insulin signaling, including expression of glucose transporter-4, whereas the treatment with enalapril was ineffective for the insulin receptor and less effective than olmesartan on the insulin-receptor substrate-1, phosphorylated-mammalian target of rapamycin and glucose transporter-4. There was a significant reduction in microvessel density in the skeletal muscle of spontaneously hypertensive rats compared with Wistar-Kyoto controls, and this was completely prevented by both olmesartan and enalapril. CONCLUSION: These results suggest that changes in insulin signaling occur in the skeletal muscle but not in the heart of untreated spontaneously hypertensive rats. In the skeletal muscle, insulin signaling was restored by olmesartan, whereas enalapril was less effective. Effective antihypertensive treatment with olmesartan or enalapril was associated with prevention of microvascular rarefaction.

Effects of insulin on endothelial and contractile function of subcutaneous small resistance arteries of hypertensive and diabetic patients.

The effect of insulin on the vasoconstriction induced by norepinephrine is at present controversial. We have previously demonstrated that high-concentration insulin may induce an increased reactivity to norepinephrine in mesenteric small resistance arteries of spontaneously hypertensive rats. The aim of the present study was to evaluate the effects of low- and high-concentration insulin on the concentration-response curves to norepinephrine and acetylcholine in subcutaneous small resistance arteries of hypertensive and diabetic patients. Twelve normotensive subjects (NT), 11 patients with essential hypertension (EH), 8 patients with non-insulin-dependent diabetes mellitus (NIDDM), and 8 patients with both EH and NIDDM (EH + NIDDM) were included in the study. Subcutaneous small resistance arteries were dissected and mounted on an isometric myograph. Concentration-response curves to norepinephrine (from 10(-8) to 10(-5) mol/l) and acetylcholine (from 10(-9) to 10(-5) mol/l) were performed in the presence or absence of insulin 715 pmol/l (low concentration) and 715 nmol/l (high concentration). A significant reduction in the contractile response to norepinephrine was observed in NT after preincubation of the vessels with both low- and high-concentration insulin. No reduction was observed in NIDDM and EH + NIDDM, while a significant decrease was obtained in EH with high-concentration insulin. Moreover, a significant difference in reduction in contractile response at maximal concentration of norepinephrine in the presence of low-concentration insulin was observed in NT compared to EH (p = 0.03), NIDDM (p = 0.02), and EH + NIDDM (p = 0.05), whereas no difference was observed with high-concentration insulin. No differences in the concentration-response curves to acetylcholine before or after precontraction with either low- or high-concentration insulin were observed in any group. In conclusion, insulin at low (physiological) concentrations seems to induce a decreased reactivity to norepinephrine in subcutaneous small resistance arteries of NT, but this effect was lost in EH, NIDDM and EH + NIDDM. This effect does not seem to involve acetylcholine-stimulated nitric oxide release.

Morning rise of blood pressure and subcutaneous small resistance artery structure.

OBJECTIVES: It has been previously demonstrated that the morning rise (MoR) of blood pressure (BP) may predict major cardiovascular events in hypertensive patients. Structural alterations of small resistance arteries, as evaluated by the tunica media to internal lumen ratio (M/L) of subcutaneous small resistance arteries, may also predict cardiovascular events. Because an increased M/L may amplify the effect of hypertensive stimuli, the present study aimed to evaluate the possible relationships between MoR and M/L in a population of hypertensive patients. METHODS: Sixty-four patients with essential hypertension were included in the present study. All patients were submitted to a biopsy of subcutaneous fat. Small resistance arteries were dissected and mounted on an isometric myograph, and the M/L was measured. In addition, MoR was calculated from ambulatory blood pressure monitoring (ABPM) according to four previously published different methods (MoR1 to MoR4). RESULTS: A statistically significant correlation was observed between M/L and MoR1 (r = 0.52, P < 0.001), MoR2 (r = 0.32, P < 0.01), MoR3 (r = 0.25, P < 0.05) and MoR4 (r = 0.27, P < 0.05), as well as between internal diameter of subcutaneous small arteries and MoR1 (r = -0.45, P < 0.001) and MoR2 (r = -0.28, P < 0.05). CONCLUSION: Our results indicate that subcutaneous small artery structure is related to MoR, possibly because an altered vascular structure may amplify BP changes or, vice versa, because a greater MoR may further damage peripheral vasculature.