The PiTSTOP study: a feasibility cluster randomized trial of delirium prevention in care homes for older people.

BACKGROUND AND OBJECTIVES: delirium is a distressing but potentially preventable condition common in older people in long-term care. It is associated with increased morbidity, mortality, functional decline, hospitalization and significant healthcare costs. Multicomponent interventions, addressing delirium risk factors, have been shown to reduce delirium by one-third in hospitals. It is not known whether this approach is also effective in long-term care. In previous work, we designed a bespoke delirium prevention intervention, called 'Stop Delirium!' In preparation for a definitive trial of Stop Delirium, we sought to address key aspects of trial design for the particular circumstances of care homes. DESIGN: a cluster randomized feasibility study with an embedded process evaluation. SETTING AND PARTICIPANTS: residents of 14 care homes for older people in one metropolitan district in the UK. INTERVENTION: Stop Delirium!: a 16-month-enhanced educational package to support care home staff to address key delirium risk factors. Control homes received usual care. MEASUREMENTS: we collected data to determine the following: recruitment and attrition; delirium rates and variability between homes; feasibility of measuring delirium, resource use, quality of life, hospital admissions and falls; and intervention implementation and adherence. RESULTS: two-thirds (215) of eligible care home residents were recruited. One-month delirium prevalence was 4.0% in intervention and 7.1% in control homes. Proposed outcome measurements were feasible, although our approach appeared to underestimate delirium. Health economic evaluation was feasible using routinely collected data. CONCLUSION: a definitive trial of delirium prevention in long-term care is needed but will require some further design modifications and pilot work.

Pulmonary vascular disease in mice xenografted with human BM progenitors from patients with pulmonary arterial hypertension.

Hematopoietic myeloid progenitors released into the circulation are able to promote vascular remodeling through endothelium activation and injury. Endothelial injury is central to the development of pulmonary arterial hypertension (PAH), a proliferative vasculopathy of the pulmonary circulation, but the origin of vascular injury is unknown. In the present study, mice transplanted with BM-derived CD133(+) progenitor cells from patients with PAH, but not from healthy controls, exhibited morbidity and/or death due to features of PAH: in situ thrombi and endothelial injury, angioproliferative remodeling, and right ventricular hypertrophy and failure. Myeloid progenitors from patients with heritable and/or idiopathic PAH all produced disease in xenografted mice. Analyses of hematopoietic transcription factors and colony formation revealed underlying abnormalities of progenitors that skewed differentiation toward the myeloid-erythroid lineage. The results of the present study suggest a causal role for hematopoietic stem cell abnormalities in vascular injury, right ventricular hypertrophy, and morbidity associated with PAH.

Hypoxia-inducible factors in human pulmonary arterial hypertension: a link to the intrinsic myeloid abnormalities.

Pulmonary arterial hypertension (PAH) is a proliferative vasculopathy characterized by high circulating CD34(+)CD133(+) proangiogenic progenitors, and endothelial cells that have pathologic expression of hypoxia-inducible factor 1 α (HIF-1α). Here, CD34(+)CD133(+) progenitor cell numbers are shown to be higher in PAH bone marrow, blood, and pulmonary arteries than in healthy controls. The HIF-inducible myeloid-activating factors erythropoietin, stem cell factor (SCF), and hepatocyte growth factor (HGF) are also present at higher than normal levels in PAH blood, and related to disease severity. Primary endothelial cells harvested from human PAH lungs produce greater HGF and progenitor recruitment factor stromal-derived factor 1 α (SDF-1α) than control lung endothelial cells, and thus may contribute to bone marrow activation. Even though PAH patients had normal numbers of circulating blood elements, hematopoietic alterations in myeloid and erythroid lineages and reticulin fibrosis identified a subclinical myeloproliferative process. Unexpectedly, evaluation of bone marrow progenitors and reticulin in nonaffected family members of patients with familial PAH revealed similar myeloid abnormalities. Altogether, the results show that PAH is linked to myeloid abnormalities, some of which may be related to increased production of HIF-inducible factors by diseased pulmonary vasculature, but findings in nonaffected family suggest myeloid abnormalities may be intrinsic to the disease process.

Loss of alveolar membrane diffusing capacity and pulmonary capillary blood volume in pulmonary arterial hypertension.

BACKGROUND: Reduced gas transfer in patients with pulmonary arterial hypertension (PAH) is traditionally attributed to remodeling and progressive loss of pulmonary arterial vasculature that results in decreased capillary blood volume available for gas exchange. METHODS: We tested this hypothesis by determination of lung diffusing capacity (DL) and its components, the alveolar capillary membrane diffusing capacity (D(m)) and lung capillary blood volume (V(c)) in 28 individuals with PAH in comparison to 41 healthy individuals, and in 19 PAH patients over time. Using single breath simultaneous measure of diffusion of carbon monoxide (DL(CO)) and nitric oxide (DL(NO)), DL and D(m) were respectively determined, and V(c) calculated. D(m) and V(c) were evaluated over time in relation to standard clinical indicators of disease severity, including brain natriuretic peptide (BNP), 6-minute walk distance (6MWD) and right ventricular systolic pressure (RVSP) by echocardiography. RESULTS: Both DL(CO) and DL(NO) were reduced in PAH as compared to controls and the lower DL in PAH was due to loss of both D(m) and V(c) (all p < 0.01). While DL(CO) of PAH patients did not change over time, DL(NO) decreased by 24 ml/min/mmHg/year (p = 0.01). Consequently, D(m) decreased and V(c) tended to increase over time, which led to deterioration of the D(m)/V(c) ratio, a measure of alveolar-capillary membrane functional efficiency without changes in clinical markers. CONCLUSIONS: The findings indicate that lower than normal gas transfer in PAH is due to loss of both D(m) and V(c), but that deterioration of D(m)/V(c) over time is related to worsening membrane diffusion.

Ventricular geometry, strain, and rotational mechanics in pulmonary hypertension.

BACKGROUND: We tested the hypothesis that right ventricular (RV) pressure overload affects RV function and further influences left ventricular (LV) geometry, which adversely affects LV twist mechanics and segmental function. METHODS AND RESULTS: Echocardiographic images were prospectively acquired in 44 patients (age, 46+/-12 years; 82% women) with evidence of pulmonary hypertension (estimated pulmonary artery systolic pressure, 71+/-23 mm Hg) and in 44 age- and gender-matched healthy subjects. Patients with intrinsic LV diseases were excluded. RV lateral wall longitudinal strain (LS) and interventricular septal (IVS) LS were reduced in the pulmonary hypertension group compared with control subjects (-15.9+/-7.6% versus -25.5+/-6.1%, P<0.001; and -17.3+/-4.4% versus -20.2+/-3.9%, P=0.002, respectively), whereas LV lateral wall LS was preserved. RV lateral wall LS and IVS LS, but not LV lateral wall LS, correlated with pulmonary artery systolic pressure (r=0.56, P<0.01; r=0.32, P<0.01) and LV eccentricity index (r=0.57, P<0.01; r=0.57, P<0.01). IVS and LV lateral wall circumferential strain (CS) were both reduced in the pulmonary hypertension group. Although IVS CS and LV lateral wall CS correlated with pulmonary artery systolic pressure and LV eccentricity index, after adjustment of CS for LV eccentricity index, differences between groups persisted for IVS CS (P<0.01) but not LV lateral wall CS (P=0.09). LV torsion was decreased in patients with pulmonary hypertension compared with control subjects (9.6+/-4.9 degrees versus 14.7+/-4.9 degrees , P<0.001). LV torsion inversely correlated with pulmonary artery systolic pressure (r=-0.39, P<0.01) and LV eccentricity index (r=-0.3, P<0.01). LV untwisting rates were similar in both groups (P=0.7). CONCLUSIONS: Chronic RV pressure overload directly affects RV longitudinal systolic deformation. RV pressure overload further influences IVS and LV geometry, which impairs LV torsion and segmental LS and CS, more for the IVS than for the free wall of the LV.