Assessing quality of care of elderly patients using the ACOVE quality indicator set: a systematic review

Background

Care of the elderly is recognized as an increasingly important segment of health care. The Assessing Care Of Vulnerable Elderly (ACOVE) quality indicators (QIs) were developed to assess and improve the care of elderly patients.

Objectives

The purpose of this review is to summarize studies that assess the quality of care using QIs from or based on ACOVE, in order to evaluate the state of quality of care for the reported conditions.

Methods

We systematically searched MEDLINE, EMBASE and CINAHL for English-language studies indexed by February 2010. Articles were included if they used any ACOVE QIs, or adaptations thereof, for assessing the quality of care. Included studies were analyzed and relevant information was extracted. We summarized the results of these studies, and when possible generated an overall conclusion about the quality of care as measured by ACOVE for each condition, in various settings, and for each QI.

Results

Seventeen studies were included with 278 QIs (original, adapted or newly developed). The quality scores showed large variation between and within conditions. Only a few conditions showed a stable pass rate range over multiple studies. Overall, pass rates for dementia (interquartile range (IQR): 11%–35%), depression (IQR: 27%–41%), osteoporosis (IQR: 34%–43%) and osteoarthritis (IQR: 29–41%) were notably low. Medication management and use (range: 81%–90%), hearing loss (77%–79%) and continuity of care (76%–80%) scored higher than other conditions. Out of the 278 QIs, 141 (50%) had mean pass rates below 50% and 121 QIs (44%) had pass rates above 50%. Twenty-three percent of the QIs scored above 75%, and 16% scored below 25%.

Conclusions

Quality of care per condition varies markedly across studies. Although there has been much effort in improving the care for elderly patients in the last years, the reported quality of care according to the ACOVE indicators is still relatively low.     

Plant growth promoting activity of an auxin and siderophore producing isolate of <Emphasis Type="Italic">Streptomyces</Emphasis> under saline soil conditions

A biocontrol Streptomyces isolate (C) was tested for its plant growth promoting qualities under saline conditions. Exposure to elevated osmotic strengths up to 300 mM NaCl increased dry weight and cfu/ml significantly. The isolate C produced indolyl-3-acetic acid (IAA) into the medium in the amount of 2.4 μg/ml. The amount of auxin increased after adding salt and reached to 4.7 μg/ml in 300 mM NaCl. Biosynthesis of siderophore was detectable and increased in presence of NaCl. Streptomyces isolate C showed good solubilization of tricalcium phosphate in culture medium with 92 mg/l. Solubilization decreased in presence of NaCl. Soil treatment with isolate C increased the growth and development of wheat plant in normal and saline conditions. In this treatment there were significant increases in germination rate, percentage and uniformity, shoot length and dry weight compared to the control. Applying the bacterial inocula increased the concentration of N, P, Fe and Mn in wheat shoots grown in normal and saline soil, but had non-significant effect on other micro and macronutrients concentrations. Results of this study show that Streptomyces isolate C has potential to be utilized as biofertilizer in saline soils.     

Regulation of (Na++K+)-ATPase by inorganic phosphate: pH dependence and physiological implications

Inhibition of Na++K+-dependent ATPase activity by Pi was maximal in the pH range of 6.1-7, but decreased with increasing pH in the range of 7-8.5. Ki of Pi was 2.8 mM at pH 7.1, and 12 mM at pH 7.8. K+-dependent phosphorylation of the enzyme by Pi, which is thought to be responsible for inhibition of ATPase activity, also decreased with increasing pH. The data suggest that (a) previously observed requirement of high Pi concentrations for inhibition of ATPase activity and associated pump fluxes may have been due to high pH of the assays; (b) at normal values of intracellular pH the pump may be partially inhibited by intracellular Pi; and (c) this effect of Pi may be amplified or dampened with alterations in intracellular pH and ATP/Pi ratio.     

Mechanisms of detergent effects on membrane-bound (Na+ + K+)-ATPase

Because the nonionic detergent octaethylene glycol dodecyl ether has been used extensively for studies on active solubilized preparations of (Na+ + K+)-ATPase, we tried to see if the detergent alters the properties of the membrane-bound enzyme prior to solubilization. Addition of the detergent, at concentrations below its critical micellar concentration, to reaction mixtures containing the highly purified membrane-bound enzyme reduced the K0.5 of ATP for (Na+ + K+)-dependent ATPase activity without affecting the maximal velocity or abolishing the negative cooperativity of the substrate-velocity curve. Under these conditions, however, the enzyme was not solubilized as evidenced by complete sedimentation of the membrane fragments containing the enzyme upon centrifugation at 100,000 X g for 30 min. Other nonsolubilizing effects of the detergent included an increase in K0.5 of K+, inhibition of Na+-dependent ATPase with no effect on K0.5 of ATP for this activity, and reductions in the spontaneous decomposition rates of the K+-sensitive phosphoenzyme obtained from ATP and the phosphoenzyme obtained from Pi. The nonsolubilizing effects of the detergent on the purified enzyme were obtained with no detectable lag, were readily reversible, and could be distinguished from its vesicle-opening effects on crude membrane preparations. Several other nonionic and ionic detergents had similar effects on the enzyme. The findings indicate (a) detergent binding to hydrophobic sites on extramembranous segments of enzyme subunits; (b) that occupation of these sites mimics the effects of ATP at a low-affinity regulatory site with no effect on high-affinity ATP binding to the catalytic site; and (c) that in studies on detergent-solubilized preparations, it is necessary to distinguish between the effects of solubilization per se and detergent effects at the regulatory site.     

(Na+ + K+)-dependent adenosine triphosphatase. Regulation of inorganic phosphate, magnesium ion, and calcium ion interactions with the enzyme by ouabain

1. (Na+ + K+)-dependent adenosine triphosphatase was phosphorylated on the alpha-subunit by Pi in the presence of Mg2+. Phosphorylation was stimulated by ouabain. The interactions of Pi, Mg2+, and ouabain with the enzyme could be explained by a random terreactant scheme in which the binding of each ligand to the enzyme increased the affinities for the other two. Dissociation constants of all steps of this scheme were estimated. 2. In the presence of Pi and ouabain and without added Mg2+, the phosphoenzyme was formed. Because this could be prevented by ethylenediaminetetraacetic acid, but not ethylene glycol bis(beta-aminoethyl ether)-N,N,N',N'-tetraacetic acid, phosphoenzyme formation under these conditions was probably dependent on traces of endogenous Mg2+. The ability of this Mg2+ to support phosphorylation could be explained by the large increase in the enzyme's affinity for Mg2+ by ouabain. 3. In the absence of ouabain, Ca2+ did not support phosphorylation and inhibited Mg2+-dependent phosphorylation. At lower concentrations, Ca2+ was competitive with Mg2+. With increasing Ca2+ concentration, negative cooperativity was observed, suggesting the existence of multiple divalent cation sites with equivalent affinities for Mg2+, but varying affinities for Ca2+. 4. In the presence of ouabain, the maximum inhibition of Mg2+-dependent phosphorylation by Ca2+ was 50%. With saturating Pi, Mg2+, and ouabain, the number of sites binding ouabain was equal to the number of sites phosphorylated. Although Ca2+ halved phosphorylation and reduced the affinity for ouabain about 100-fold, it did not affect the number of ouabain sites. 5. We suggest that the enzyme is an alpha-oligomer and that the half-of-the-sites reactivity for phosphorylation in the presence of Pi, Mg2+, ouabain, and optimal Ca2+ is caused by (a) ouabain-induced increase in the affinities of both protomers for Mg2+ and (b) the inability of Ca2+ to replace Mg2+ on one of the protomers.     

Transport ATPase of erythrocyte membrane: sensitivities of Na plus, K, plus-ATPase and Kplus-phosphatase activities to ouabain.

Cardiac glycosides are inhibitors of Na⁺,K⁺-ATPase, and K⁺-phosphatase activities of the transport enzyme. Previous studies have shown that when the sensitivities of these two activities to ouabain are compared by the addition of varying concentrations of the drug to the assay media, the K⁺-phosphatase is significantly less sensitive than Na⁺,K⁺-ATPase. This work was done to seek an explanation for this phenomenon. 3-O-Methyl-fluorescein phosphate was used as substrate for the continuous fluorimetric assay of K⁺-phosphatase obtained from human red cells. When ouabain was added to the assay medium, a time-dependent inhibition of K⁺-phosphatase was observed. The rate of inhibition was also influenced by the order of additions of K⁺ and ouabain. In view of these results, several enzyme samples exposed to ouabain for varying lengths of time were prepared, and their Na⁺,K⁺-ATPase and K⁺-phosphatase activities were then determined. A good correlation between the extent of inhibition of the two activities was obtained. These results prove that the previously observed discrepancies between the sensitivities of Na⁺,K⁺-ATPase and K⁺-phosphatase to ouabain are due to the different kinetics of drug interaction with the enzyme under the different conditions of the two assays and that once a certain level of ouabain binding to the enzyme is achieved, both activities are equally inhibited.     

Na+,K+-ATPase: half-of-the-subunits cross-linking reactivity suggests an oligomeric structure containing a minimum of four catalytic subunits

When Na⁺,K⁺-ATPase was reacted with Cu²⁺ and o-phenanthroline under conditions where the formation of a cross-linked dimer of the catalytic subunit (α,α-dimer) is dependent on the prior phosphorylation of the enzyme by ATP, it was found that (a) only half of the α-subunit content is phosphorylated, and only half is cross-linked; and (b) a phosphorylated α-subunit is cross-linked to an unphosphorylated α-subunit. It is suggested that the functional unit of the membrane-bound enzyme contains at least four α-subunits, and that ligand-induced half-of-the-sites reactivity may be exerted across two different intersubunit domains of the tetramer.     

Characterization of Na+-dependent phosphate transport in cardiac sarcolemmal vesicles

Pi uptake by purified bovine cardiac sarcolemmal vesicles was stimulated by an inwardly directed Na+ gradient, but not by such gradients of K+, Rb+, Li+, and choline. When Na+ was present both inside and outside the vesicles, or when Na+ gradient was dissipated by monensin, the Na+-dependent Pi uptake increased with time, reached a peak, and then declined approaching a steady state. The initial rate of Na+-dependent Pi uptake was a saturable function of Pi concentration (Km = 0.5 mM). These findings indicate the existence of a Na+,Pi-cotransporter in the sarcolemma. The Na+-activation curve of the Pi uptake exhibited positive cooperativity, suggesting the requirement for multiple Na+ binding to the functional unit of the carrier. The initial rate of Na+-dependent Pi uptake decreased as extra-vesicular pH increased in the range of 5.5-8.7. The uptake rate increased under conditions that are known or expected to generate an inside-negative membrane potential, indicating that Pi uptake is accompanied by the uptake of positive charge. These results suggest the electrogenic cotransports of two Na+ and one H2PO4-. We conclude that this cotransporter catalyzes the secondary active transport of Pi across the cardiac plasma membrane and regulates myocardial energy metabolism. We also suggest that the cotransporter may control intracellular Na+ and thus be involved in the regulation of trans-sarcolemmal Ca2+ movement and cardiac contractility.     

Focal adhesions are sites of integrin extension

Integrins undergo global conformational changes that specify their activation state. Current models portray the inactive receptor in a bent conformation that upon activation converts to a fully extended form in which the integrin subunit leg regions are separated to enable ligand binding and subsequent signaling. To test the applicability of this model in adherent cells, we used a fluorescent resonance energy transfer (FRET)–based approach, in combination with engineered integrin mutants and monoclonal antibody reporters, to image integrin α5β1 conformation. We find that restricting leg separation causes the integrin to adopt a bent conformation that is unable to respond to agonists and mediate cell spreading. By measuring FRET between labeled α5β1 and the cell membrane, we find extended receptors are enriched in focal adhesions compared with adjacent regions of the plasma membrane. These results demonstrate definitely that major quaternary rearrangements of β1-integrin subunits occur in adherent cells and that conversion from a bent to extended form takes place at focal adhesions.