Excess mortality after hip fracture in elderly persons from Europe and the USA: the CHANCES project

BACKGROUND

Hip fractures are associated with diminished quality of life and survival especially amongst the elderly.

OBJECTIVE

All-cause mortality after hip fracture was investigated to assess its magnitude.

METHODS

A total of 122 808 participants from eight cohorts in Europe and the USA were followed up for a mean of 12.6 years, accumulating 4273 incident hip fractures and 27 999 deaths. Incident hip fractures were assessed through telephone interviews/questionnaires or national inpatient/fracture registries, and causes of death were verified with death certificates. Cox proportional hazards models and the time-dependent variable methodology were used to assess the association between hip fracture and mortality and its magnitude at different time intervals after the injury in each cohort. We obtained the effect estimates through a random-effects meta-analysis.

RESULTS

Hip fracture was positively associated with increased all-cause mortality; the hazard ratio (HR) in the fully adjusted model was 2.12, 95% confidence interval (CI) 1.76-2.57, after adjusting for potential confounders. This association was stronger amongst men [HR: 2.39, 95% CI: 1.72-3.31] than amongst women [HR: 1.92, 95% CI: 1.54-2.39], although this difference was not significant. Mortality was higher during the first year after the hip fracture [HR: 2.78, 95% CI: 2.12-3.64], but it remained elevated without major fluctuations after longer time since hip fracture [HR (95% CI): 1.89 (1.50-2.37) after 1-4 years; 2.15 (1.81-2.55) after 4-8 years; 1.79 (1.57-2.05) after 8 or more years].

CONCLUSION

In this large population-based sample of older persons across eight cohorts, hip fracture was associated with excess short- and long-term all-cause mortality in both sexes.

Changes in muscle mass, fat mass, and bone mineral content in the legs after stroke: a 1 year prospective study

Demineralization and muscle atrophy, common among patients with hemiplegia, may be risk factors for future hip fracture. The aim of this longitudinal study was to investigate changes in lean (muscle) mass and bone mineral content (BMC) of the legs during the first year after stroke according to the patient's ambulatory level. Twenty-five patients immobilized due to acute stroke were followed. BMC and lean mass of each leg were measured at a mean of 7 days, 2 months, 7 months, and 1 year after the stroke using dual-energy X-ray absorptiometry. Both BMC and lean mass had decreased significantly in the paretic leg (p < 0.05) at the 1 year evaluation and the loss was significantly greater on the paretic side compared with the nonparetic side (p < 0.001). Patients who had not relearned to walk at the 2 month evaluation (n = 12) lost 6% (p < 0.05) of their lean mass in the paretic leg during this time period, and this mass was not regained within the subsequent 10 months. In contrast, a significant 5% loss of lean mass found at 2 months on the nonparetic side was regained completely. With respect to the patients who relearned to walk within the first 2 months (n = 13) lean mass had increased by 5% after 1 year (p < 0.05) in the nonparetic leg, whereas no significant changes were found in the paretic leg during follow-up. Both groups of patients did, however, lose bone mineral in the paretic leg during the first year after stroke (9% and 6%, respectively, p < 0.05), but only the patients who were still unable to walk by 2 months had significant bone loss in the nonparetic leg also (3%, p < 0.05). Thus, lean muscle mass is rapidly lost and may be regained shortly after stroke, whereas loss of BMC appears difficult to prevent, especially on the paretic side. Regaining muscle mass may, however, slow the loss of bone mineral.

Ambulatory level and asymmetrical weight bearing after stroke affects bone loss in the upper and lower part of the femoral neck differently: bone adaptation after decreased mechanical loading

The aim of this 1-year prospective study of acute stroke patients was to determine the effects of walking and asymmetrical weight bearing on the loss of bone mineral in the upper and lower femoral neck. Forty patients were followed. Eight remained unable to walk, whereas 32 relearned to walk independently within 7 months (12 shortly after the stroke, 15 by 2 months, 5 by 7 months). Bone mineral density (BMD) was measured in the proximal femur within the first week after stroke and 1 year later; regional BMD changes were computed for the lower and upper femoral neck. The lower part of the femoral neck is mainly influenced by compressive stresses of the hip, the upper part by tensile stresses during walking. When comparing mean BMD loss in groups of patients according to when they relearned to walk, a statistically significant trend in BMD loss was found in the lower femoral neck on both the paretic and nonparetic sides (p < 0.01 and p = 0.01, respectively), whereas, for the upper femoral neck, no significant trend was seen (p >/= 0.1). In addition, the body weight distribution during standing was assessed by use of a force-plate in 38 patients who could stand independently at the 7 month evaluation. The only significant correlation between changes in BMD and asymmetrical weight bearing was found in the lower femoral neck on the paretic side (r = 0.6, p < 0.001). In conclusion, this study shows that the reduction in BMD in the femoral neck occurs mainly in the lower part of the neck and on the paretic side. The BMD loss depended on when or if the patients relearned to walk, but also on the amount of body weight born on the paretic leg. Thus, measuring the lower part of the femoral neck gives a better estimate of the impact of gait and weight bearing than measuring the total femoral neck.

Transmission of HIV Drug Resistance and the Predicted Effect on Current First-line Regimens in Europe

Transmitted human immunodeficiency virus drug resistance in Europe is stable at around 8%. The impact of baseline mutation patterns on susceptibility to antiretroviral drugs should be addressed using clinical guidelines. The impact on baseline susceptibility is largest for nonnucleoside reverse transcriptase inhibitors.

Background. Numerous studies have shown that baseline drug resistance patterns may influence the outcome of antiretroviral therapy. Therefore, guidelines recommend drug resistance testing to guide the choice of initial regimen. In addition to optimizing individual patient management, these baseline resistance data enable transmitted drug resistance (TDR) to be surveyed for public health purposes. The SPREAD program systematically collects data to gain insight into TDR occurring in Europe since 2001.

Methods. Demographic, clinical, and virological data from 4140 antiretroviral-naive human immunodeficiency virus (HIV)–infected individuals from 26 countries who were newly diagnosed between 2008 and 2010 were analyzed. Evidence of TDR was defined using the WHO list for surveillance of drug resistance mutations. Prevalence of TDR was assessed over time by comparing the results to SPREAD data from 2002 to 2007. Baseline susceptibility to antiretroviral drugs was predicted using the Stanford HIVdb program version 7.0.

Results. The overall prevalence of TDR did not change significantly over time and was 8.3% (95% confidence interval, 7.2%–9.5%) in 2008–2010. The most frequent indicators of TDR were nucleoside reverse transcriptase inhibitor (NRTI) mutations (4.5%), followed by nonnucleoside reverse transcriptase inhibitor (NNRTI) mutations (2.9%) and protease inhibitor mutations (2.0%). Baseline mutations were most predictive of reduced susceptibility to initial NNRTI-based regimens: 4.5% and 6.5% of patient isolates were predicted to have resistance to regimens containing efavirenz or rilpivirine, respectively, independent of current NRTI backbones.

Conclusions. Although TDR was highest for NRTIs, the impact of baseline drug resistance patterns on susceptibility was largest for NNRTIs. The prevalence of TDR assessed by epidemiological surveys does not clearly indicate to what degree susceptibility to different drug classes is affected.

Walking after stroke: does it matter? Changes in bone mineral density within the first 12 months after stroke. A longitudinal study

Stroke patients have increased risk of hip fractures. Nearly all fractures occur on the hemiplegic side, and reduced bone mineral density (BMD) may be an important predisposing factor. The aim of this study was to investigate the degree of demineralization within the first year after stroke, and to elucidate a possible difference in patients with high versus low ambulatory levels. Forty acute stroke patients were followed (17 initially wheelchair-bound and 23 initially ambulatory). BMD was measured in the proximal femur bilaterally at a mean 6 days, 7 months and 1 year after stroke onset using dual-energy X-ray absorptiometry. Ambulatory status was independently associated with changes in BMD (p < or = 0.005) 1 year after stroke. The 17 initially wheelchair-bound patients had a significant 10% reduction in BMD at the paretic side and 5% reduction at the non-paretic side (p < 0.001), while the 23 patients initially able to walk had a significant loss (3%) only at the paretic side (p = 0.01). The analysis also indicated that the major reduction in BMD took place within the first 7 months. Two months after stroke 12 of the wheelchair-bound patients had relearned to walk. At the paretic side the 1 year changes in BMD in the patients who stayed wheelchair-bound, the patients who re-learned to walk within the first 2 months and the patients who were able to walk throughout the study were 13%, 8% and 3%, respectively, and a statistically significant trend with ambulatory level was found (p = 0.007). This study provides clear evidence that lack of mobility and weight-bearing early after stroke is an important factor for the greater bone loss in the paretic leg, but that relearning to walk within the first 2 months after stroke, even with the support of another person, may reduce the bone loss after immobilization.

Bone mineral density in acute stroke patients: low bone mineral density may predict first stroke in women

BACKGROUND AND PURPOSE

Osteoporosis and stroke share several risk factors, including age, smoking, low physical activity, and hypertension. Thus, low bone mineral density (BMD) and high stroke risk may be related. We examined the relationship between BMD and acute stroke in noninstitutionalized men and women aged >/=60 years.

METHODS

Sixty-three stroke patients (33 women and 30 men) and 188 control subjects from the general population were included. BMD was measured by using dual-energy x-ray absorptiometry at both proximal femurs. The measurements of the stroke patients were performed 6 days after the onset of stroke.

RESULTS

The BMD at the femoral neck in the female stroke patients was 8% lower than in the control subjects (P:=0.007). In men, no difference in BMD between the stroke patients and their controls was found. Women with BMD values in the lowest quartile had a higher risk of stroke than women with BMD values in the highest quartile (OR 4.8), and the probability value for linear trend over the quartiles was statistically significant (P:=0.003). The OR for stroke increased 1.9 per SD (0.13 g/cm(2)) reduction in BMD, and the association between low BMD and stroke in women remained significant when the analysis was adjusted for potential confounders.

CONCLUSIONS

Female, but not male, stroke patients have lower BMD than population controls. Low BMD may predict stroke in women.

Innervation of the human middle meningeal artery: immunohistochemistry, ultrastructure, and role of endothelium for vasomotility

The majority of nerve fibers in the middle meningeal artery and branching arterioles are sympathetic, storing norepinephrine and neuropeptide Y (NPY). A sparse supply of fibers contain acetylcholinesterase activity and immunoreactivity toward vasoactive intestinal peptide (VIP), peptidine histidine methionine (PHM), and calcitonin gene-related peptide (CGRP). Only few substance P and neuropeptide K immunoreactive fibers are noted. Electronmicroscopy shows axons and terminals at the adventitial medial border of the human middle meningeal artery, with a fairly large distance to the smooth muscle cells (>500 nM). Several axon profiles contain vesicles of different types, including putative sensory profiles. The perivascularly stored signal substances, norepinephrine and NPY induced vasoconstrictor. Relaxations were induced by acetylcholine and substance P, and these were significantly reduced in arteries without endothelium, while the responses to norepinephrine, NPY, VIP, PHM, and CGRP were not changed by endothelium removal. Blockade experiments showed that the vasomotor responses to norepinephrine were blocked by prazosin, to NPY by BIBP 3226, acetylcholine by atropin, substance P by RP 67580, and the human alpha-CGRP response by human alpha-CGRP(8-37).

Serum osteoprotegerin is a predictor for incident cardiovascular disease and mortality in a general population: the Tromsø Study

BACKGROUND

Osteoprotegerin (OPG) concentration in serum is associated with the presence and severity of atherosclerosis.

OBJECTIVE

To investigate the association between serum osteoprotegerin and the risk of a future myocardial infarction, ischemic stroke and mortality in a general population.

PATIENTS/METHODS

OPG was measured in serum collected from 6265 subjects recruited from a general population without a prior myocardial infarction and ischemic stroke (the Tromsø Study). Incident myocardial infarction, ischemic stroke and mortality were registered during follow-up. Cox regression models were used to estimate crude and adjusted hazard ratios and 95% confidence intervals (HR; 95% CI).

RESULTS

There were 575 myocardial infarctions, 284 ischemic strokes and 824 deaths (146 deaths as a result of ischemic heart disease, 78 deaths because of stroke and 600 deaths due to other causes) in the cohort during a median of 10.6 years of follow-up. Serum OPG (per SD [1.13 ng mL(-1)] increase in OPG) was associated with an increased risk of a myocardial infarction (1.20; 1.11-1.31), ischemic stroke (1.32; 1.18-1.47), total mortality (1.34; 1.26-1.42), death because of ischemic heart disease, (1.35; 1.18-1.54), stroke (1.44; 1.19-1.75) and non-vascular causes (1.31; 1.22-1.41) after adjustment for age, gender, current smoking, systolic blood pressure, body mass index, high density lipoprotein cholesterol, total cholesterol, creatinine, high sensitivity C-reactive protein (CRP) and diabetes mellitus or HbA1c > 6.1%. No association was detected between OPG and incident hemorrhagic stroke (1.02; 0.73-1.43).

CONCLUSIONS

Serum OPG was associated with future risk of myocardial infarction, ischemic stroke, total mortality, mortality of ischemic heart disease, stroke and of non-vascular causes independent of traditional cardiovascular risk factors.

24-hour home pad weighing test versus 1-hour ward test in the assessment of mild stress incontinence

Twenty-three normal volunteers and 31 women admitted for stress or mixed incontinence underwent two 24-hour home pad weighing tests. In the patients the test result was compared with the result obtained with the 1-hour ward pad weighing test. Median pad weight gain was 4 g/24-h, with an upper 99% limit of 8 g/24 h in normal women. The median urine loss was 17 g/24-h in the patients. Eighteen (58%) patients were classified as incontinent according to the result of the 1-h ward test, versus 28 (90%) according to the result of the 24-h home test. There was no significant correlation between the result of the 1-h test and the 24-h test. In the patients, test-retest analysis showed a significant variation in the result of the 24-h test. It is concluded that the better of two 24-h home tests is more sensitive for confirmation incontinence than is one 1-h ward test. Consequently, the 24-h home test is of practical use as a screening test for incontinence. The reproducibility of the test, however, seems insufficiently satisfactory to allow of its use in comparative scientific studies.

Combination of budesonide/formoterol more effective than fluticasone/salmeterol in preventing exacerbations in chronic obstructive pulmonary disease: the PATHOS study

OBJECTIVES

Combinations of inhaled corticosteroids (ICSs) and long-acting β2 -agonists (LABAs) are recommended for patients with moderate and severe chronic obstructive pulmonary disease (COPD). However, it is not known whether different fixed combinations are equally effective. The aim of this study was to investigate exacerbation rates in primary care patients with COPD treated with budesonide/formoterol compared with fluticasone/salmeterol.

METHODS

Patients with physician-diagnosed COPD and a record of postdiagnosis treatment with a fixed combination of budesonide/formoterol or fluticasone/salmeterol were included. Data from primary care medical records were linked to those from Swedish national hospital, drug and cause of death registers. Pairwise (1 : 1) propensity score matching was carried out at the index date (first prescription) by prescribed fixed ICS/LABA combination. Exacerbations were defined as hospitalizations, emergency visits and collection of oral steroids or antibiotics for COPD. Yearly event rates were compared using Poisson regression.

RESULTS

Matching of 9893 patients (7155 budesonide/formoterol and 2738 fluticasone/salmeterol) yielded two cohorts of 2734 patients, comprising 19 170 patient-years. The exacerbation rates were 0.80 and 1.09 per patient-year in the budesonide/formoterol and fluticasone/salmeterol groups, respectively (difference of 26.6%; P < 0.0001); yearly rates for COPD-related hospitalizations were 0.15 and 0.21, respectively (difference of 29.1%; P < 0.0001). All other healthcare outcomes were also significantly reduced with budesonide/formoterol versus fluticasone/salmeterol.

CONCLUSIONS

Long-term treatment with fixed combination budesonide/formoterol was associated with fewer healthcare utilization-defined exacerbations than fluticasone/salmeterol in patients with moderate and severe COPD.

Heterotrophic bacteria growing in association with Methylococcus capsulatus (Bath) in a single cell protein production process

The methanotrophic bacterium Methylococcus capsulatus (Bath) grows on pure methane. However, in a single cell protein production process using natural gas as methane source, a bacterial consortium is necessary to support growth over longer periods in continuous cultures. In different bioreactors of Norferm Danmark A/S, three bacteria consistently invaded M. capsulatus cultures growing under semi-sterile conditions in continuous culture. These bacteria have now been identified as a not yet described member of the Aneurinibacillus group, a Brevibacillus agri strain, and an acetate-oxidiser of the genus Ralstonia. The physiological roles of these bacteria in the bioreactor culture growing on natural, non-pure methane gas are discussed. The heterotrophic bacteria do not have the genetic capability to produce either the haemolytic enterotoxin complex HBL or non-haemolytic enterotoxin.

Transmission of HIV-1 drug-resistant variants: prevalence and effect on treatment outcome

BACKGROUND

Human immunodeficiency virus type 1 (HIV-1) drug resistance is an important threat to the overall success of antiretroviral therapy (ART). Because of the limited sensitivity of commercial assays, transmitted drug resistance (TDR) may be underestimated; thus, the effect that TDR has on treatment outcome needs to be investigated. The objective of this study was to investigate the prevalence of TDR in HIV-infected patients and to evaluate the significance of TDR with respect to treatment outcome by analyzing plasma viral RNA and peripheral blood mononuclear cell proviral DNA for the presence of drug resistance mutations.

METHODS

In a prospective study, we investigated the level of TDR in 61 patients by comparing the results of a sensitive multiplex-primer-extension approach (termed HIV-SNaPshot) that is capable of screening for 9 common nucleoside reverse-transcriptase inhibitor and nonnucleotide reverse-transcriptase inhibitor mutations with those of a commercial genotyping kit, ViroSeq (Abbott).

RESULTS

Twenty-two patients were found to carry mutations. More patients with TDR were identified by the HIV-SNaPshot assay than by ViroSeq analysis (33% vs 13%; [P=.015). There was no significant difference in the time from initiation of ART to virological suppression between susceptible patients and those carrying low- or high-level resistance mutations (mean +/- standard deviation, 128 +/- 59.1 vs 164.9 +/- 120.4; P=.147). Furthermore, analyses of CD4 cell counts showed no significant difference between these 2 groups 1 year after the initiation of ART (mean, 184 vs 219 cells/microL; P=.267).

CONCLUSION

We found the prevalence of TDR in recently infected ART-naive patients to be higher than that estimated by ViroSeq genotyping alone. Follow-up of patients after treatment initiation showed a trend toward there being more clinical complications for patients carrying TDR, although a significant effect on treatment outcome could not be demonstrated. Therefore, the clinical relevance of low-abundance resistant quasispecies in early infection is still in question.

Dislocation following total hip arthroplasty

The rate of postoperative dislocation after Stanmore total hip arthroplasty in 427 cases was 4.9%; 1.4% were classified as recurrent cases. Retroversion of the acetabular component and postoperative joint laxity were the only factors that were found to predispose to dislocation. The importance of preserving the effective femoral neck length during total hip arthroplasty is emphasized.

Large eccentric strength increase using the Copenhagen Adduction exercise in football: A randomized controlled trial

Hip adductor injuries are frequent in football, and players with low adductor strength appear to be at increased risk of injury. High adductor muscle activity has been shown in the Copenhagen Adduction exercise (CA); however, an associated strength gain has not been investigated. This study aims to examine the eccentric hip adduction strength (EHAD) gain using the CA in-season. Two U-19 sub-elite football teams, including 24 football players, were randomized to either an 8-week supervised progressive training program in addition to the usual training (intervention) or to continue training as usual (control). EHAD, eccentric hip abduction strength (EHAB), and side-bridge endurance were measured using reliable test procedures at baseline and follow-up by a blinded tester. There was a significant interaction between group and time on EHAD, EHAB, and EHAD/EHAB ratio (P < 0.025). The intervention group demonstrated a 35.7% increase in EHAD (P < 0.001); a 20.3% increase in EHAB (P = 0.003), and 12.3% increase in EHAD/EHAB ratio (P = 0.019). No significant within-group differences were found in the control group (P > 0.335). Compliance was 91.25%, and median muscle soreness ranged from 0 to 2. The CA implemented in-season with an 8-week progressive training program elicited a large significant increase in EHAD, EHAB, and EHAD/EHAB ratio.

Effect of early supervised progressive resistance training compared to unsupervised home-based exercise after fast-track total hip replacement applied to patients with preoperative functional limitations. A single-blinded randomised controlled trial

OBJECTIVE

To examine if 2 weekly sessions of supervised progressive resistance training (PRT) in combination with 5 weekly sessions of unsupervised home-based exercise is more effective than 7 weekly sessions of unsupervised home-based exercise in improving leg-extension power of the operated leg 10 weeks after total hip replacement (THR) in patients with lower pre-operative function.

METHOD

A total of 73 patients scheduled for THR were randomised (1:1) to intervention group (IG, home based exercise 5 days/week and PRT 2 days/week) or control group (CG, home based exercise 7 days/week). The primary endpoint was change in leg extension power at 10 week follow up. Secondary outcomes were isometric hip muscle strength, sit-to-stand test, stair climb test, 20 m walking speed and patient-reported outcome (HOOS).

RESULTS

Sixty-two completed the trial (85%). Leg extension power increased from baseline to the 10 week follow up in both groups; mean [95% CI] IG: 0.29 [0.13; 0.45] and CG: 0.26 [0.10; 0.42] W/kg, with no between-group difference (primary outcome) (P = 0.79). Maximal walking speed (P = 0.008) and stair climb performance (P = 0.04) improved more in the IG compared to CG, no other between-group differences existed.

CONCLUSIONS

In this trial, supervised PRT twice a week in addition to 5 weekly sessions of unsupervised exercise for 10 weeks was not superior to 7 weekly sessions of unsupervised home-based exercise for 10 weeks in improving the primary outcome, leg-extension power of the operated leg, at the primary endpoint 10 weeks after surgery in THR patients with lower pre-operative function.

TRIAL REGISTRATION

NCT01214954.

T cells detect intracellular DNA but fail to induce type I IFN responses: implications for restriction of HIV replication

HIV infects key cell types of the immune system, most notably macrophages and CD4+ T cells. Whereas macrophages represent an important viral reservoir, activated CD4+ T cells are the most permissive cell types supporting high levels of viral replication. In recent years, it has been appreciated that the innate immune system plays an important role in controlling HIV replication, e.g. via interferon (IFN)-inducible restriction factors. Moreover, innate immune responses are involved in driving chronic immune activation and the pathogenesis of progressive immunodeficiency. Several pattern recognition receptors detecting HIV have been reported, including Toll-like receptor 7 and Retinoic-inducible gene-I, which detects viral RNA. Here we report that human primary T cells fail to induce strong IFN responses, despite the fact that this cell type does express key molecules involved in DNA signaling pathways. We demonstrate that the DNA sensor IFI16 migrates to sites of foreign DNA localization in the cytoplasm and recruits the signaling molecules stimulator of IFN genes and Tank-binding kinase, but this does not result in expression of IFN and IFN-stimulated genes. Importantly, we show that cytosolic DNA fails to affect HIV replication. However, exogenous treatment of activated T cells with type I IFN has the capacity to induce expression of IFN-stimulated genes and suppress HIV replication. Our data suggest the existence of an impaired DNA signaling machinery in T cells, which may prevent this cell type from activating cell-autonomous anti-HIV responses. This phenomenon could contribute to the high permissiveness of CD4+ T cells for HIV-1.

Relation between serum osteoprotegerin and carotid intima media thickness in a general population - the Tromsø Study

BACKGROUND

 Previous studies have reported conflicting results on the relation between serum osteoprotegerin (OPG) concentration and carotid intima media thickness (CIMT).

PATIENTS/METHODS

 The present study was conducted to investigate the relations between OPG, risk factors for cardiovascular diseases (CVD) and carotid intima media thickness (CIMT) in a large cross-sectional study including 6516 subjects aged 25-85years who participated in a population-based health survey.

RESULTS

 CIMT increased significantly across tertiles of OPG after adjustment for traditional cardiovascular risk factors such as age, gender, smoking, total cholesterol, high-density lipoprotein (HDL) cholesterol, C-reactive protein (CRP), body mass index (BMI), systolic blood pressure, CVD and diabetes mellitus (P<0.0001). There was a significant interaction between age and OPG (P=0.026). The risk of being in the uppermost quartile of CIMT was reduced (OR 0.52, 95% CI 0.30-0.88) with each standard deviation (SD) higher level of OPG in subjects <45years (n=444), whereas subjects ≥55years of age (n=4884) had an increased risk of being in the uppermost quartile of CIMT (OR 1.19, 95% CI 1.10-1.29) after adjustment for traditional CVD risk factors.

CONCLUSIONS

Age has a differential impact on the association between OPG and CIMT in a general population. The present findings may suggest that increased serum OPG does not promote early atherosclerosis in younger subjects.

Influence of statin treatment on platelet inhibition by clopidogrel - a randomized comparison of rosuvastatin, atorvastatin and simvastatin co-treatment

OBJECTIVES

Possible interactions between clopidogrel and atorvastatin, simvastatin or rosuvastatin (a 'non-CYP3A4' metabolized statin) were investigated in a randomized prospective study using sensitive and specific ex vivo platelet function tests.

METHODS

Patients with coronary artery disease participating in a double-blind study comparing lipid-lowering effects of atorvastatin (20-80 mg OD; n = 22) and rosuvastatin (10-40 mg OD; n = 24) were studied before and after 2 weeks treatment with clopidogrel 75 mg OD after completed statin dose titration. In addition, 23 patients were randomized to open-label simvastatin 40 mg OD.

RESULTS

Clopidogrel inhibited 10 mumol L(-1) ADP-induced platelet aggregation by 40 +/- 27%, 57 +/- 28% and 51 +/- 29%, respectively, in patients on rosuvastatin, atorvastatin and simvastatin treatment. The other platelet tests yielded similar results. No dose-dependent effects of rosuvastatin or atorvastatin co-treatment on clopidogrel efficacy were observed.

CONCLUSIONS

Treatment with CYP3A4 metabolized statins, atorvastatin or simvastatin, did not attenuate the platelet inhibitory effect of clopidogrel maintenance treatment compared with the non-CYP3A4 metabolized, rosuvastatin.

Limited cross-border infections in patients newly diagnosed with HIV in Europe

BACKGROUND

International travel plays a role in the spread of HIV-1 across Europe. It is, however, not known whether international travel is more important for spread of the epidemic as compared to endogenous infections within single countries. In this study, phylogenetic associations among HIV of newly diagnosed patients were determined across Europe.

RESULTS

Data came from the SPREAD programme which collects samples of newly diagnosed patients that are representative for national HIV epidemics. 4260 pol sequences from 25 European countries and Israel collected in 2002-2007 were included.We identified 457 clusters including 1330 persons (31.2% of all patients). The cluster size ranged between 2 and 28. A number of 987 patients (74.2%) were part of a cluster that consisted only of patients originating from the same country. In addition, 135 patients (10.2%) were in a cluster including only individuals from neighboring countries. Finally, 208 patients (15.6%) clustered with individuals from countries without a common border. Clustering with patients from the same country was less prevalent in patients being infected with B subtype (P-value <0.0001), in men who have sex with men (P-value <0.0001), and in recently infected patients (P-value =0.045).

CONCLUSIONS

Our findings indicate that the transmission of HIV-1 in Europe is predominantly occurring between patients from the same country. This could have implications for HIV-1 transmission prevention programmes. Because infections through travelling between countries is not frequently observed it is important to have good surveillance of the national HIV-1 epidemics.

Doxepin in the treatment of female detrusor overactivity: a randomized double-blind crossover study

A total of 19 women with detrusor overactivity and associated symptoms completed a double-blind placebo-controlled crossover study of doxepin. All patients had previously failed to respond to conventional pharmacotherapy. Doxepin was given at bedtime in a single 50 mg. dose for the first 2 weeks and, if needed, the dose was increased with 25 mg. in the morning for the last week of the 3-week treatment period, which was followed by 2 weeks of washout before crossover. The preference for doxepin to placebo was statistically significant (p less than 0.01). Doxepin caused a significant decrease in the nighttime micturition frequency and the nighttime incontinence episodes (p less than 0.05). Urine loss at the standardized 1-hour pad weighing test decreased significantly during treatment with doxepin although statistical significance (p equals 0.07) was not obtained. Cystometric parameters (first sensation and maximum cystometric capacity) improved significantly during treatment with doxepin (p less than 0.06 and less than 0.04, respectively). Side effects were frequent but mild. Suggestions for use of this tricyclic antidepressant in women with detrusor overactivity and possible mechanisms of action are discussed.

Impact of osteoporotic fracture type and subsequent fracture on mortality: the Tromsø Study

Less is known about the impact of non-hip non-vertebral fractures (NHNV) on early death. This study demonstrated increased risk of dying following hip and NHNV fractures which was further increased by a subsequent fracture. This highlights the importance of early intervention to prevent both initial and subsequent fractures and improve survival.

INTRODUCTION

Osteoporotic fractures are a major health concern. Limited evidence exists on their impact on mortality in ageing populations. This study examined the contribution of initial fracture type and subsequent fracture on mortality in a Norwegian population that has one of the highest rates of fractures.

METHODS

The Tromsø Study is a prospective population-based cohort in Norway. Women and men aged 50+ years were followed from 1994 to 2010. All incident hip and non-hip non-vertebral (NHNV) fractures were registered. NHNV fractures were classified as either proximal or distal. Information on self-reported co-morbidities, lifestyle factors, general health and education level was collected. Multivariable Cox models were used to quantify mortality risk with incident and subsequent fractures analysed as time-dependent variables.

RESULTS

Of 5214 women and 4620 men, 1549 (30%) and 504 (11%) sustained a fracture, followed by 589 (38%) and 254 (51%) deaths over 10,523 and 2821 person-years, respectively. There were 403 (26%) subsequent fractures in women and 68 (13%) in men. Hip fracture was associated with a two-fold increase in mortality risk (HR 2.05, 95% CI 1.73-2.42 in women and 2.49, 95% CI 2.00-3.11 in men). Proximal NHNV fractures were associated with 49% and 81% increased mortality risk in women and men (HR 1.49, 95% CI 1.21-1.84 and 1.81, 95% CI 1.37-2.41), respectively. Distal NHNV fractures were not associated with mortality. Subsequent fracture was associated with 89% and 77% increased mortality risk in women and men (HR 1.89, 95% CI 1.52-2.35 and 1.77, 95% CI 1.16-2.71), respectively.

CONCLUSION

Hip, proximal NHNV and subsequent fractures were significantly associated with increased mortality risk in the elderly, highlighting the importance of early intervention.

Nosocomial HIV-transmission in an outpatient clinic detected by epidemiological and phylogenetic analyses

OBJECTIVE

To determine if a case of HIV-infection in a patient (GP) with common variable immunodeficiency, and with no known risk factors for HIV-infection, could be due to horizontal nosocomial transmission.

METHODS

For determination of time of transmission stored serum-samples from GP were analysed for HIV RNA content. Patient records were used to identify patients, who had received intravenous therapy on the same day as GP. Samples from GP and these possible source patients were identified and phylogenetic analyses of the env, gag and RT-encoding region of pol were performed. Furthermore, routines in conjunction with intravenous therapy were examined.

RESULTS

We identified a patient (FDL) harbouring virus almost indistinguishable from the virus isolated from GP. The pairwise nucleotide distance between the C2-V3-C3 region of the env and gag sequences from the two patients were 1.9 and 0.9% respectively. In addition, GP harboured HIV RNA with a foscarnet resistance mutation further lending support to virus from the foscarnet-treated FDL being the source of the infection. Interestingly, GP experienced increases in immunoglobulin production after contracting the HIV-infection, and decreases after antiretroviral-induced viral suppression. A clinical procedure which, under stressful conditions, could lead to breaches in infection control measures was identified. The source of the infection was most likely a contaminated multidose vial.

CONCLUSION

Through epidemiological and phylogenetic analyses a case of horizontal nosocomial HIV-transmission was disclosed. Identification of multidose vials as possible vehicles for horizontal nosocomial transmission recently led to the recommendation of restriction of the use of multidose vials, a recommendation supported by the present study. The study underlies the importance of a constant survey of infection control precautions.

Variations in urethral and bladder pressure during stress episodes in healthy women

Pressure variations in the urethra and bladder during stress episodes and their time separations were investigated in 30 healthy female volunteers. The pressure was measured by means of a double microtip transducer catheter with the distal sensor in the bladder and the proximal sensor at the bladder neck, the mid-urethra and the distal urethra. In advance of the pressure spike during cough a pressure rise was demonstrated in the bladder and at all 3 sites of measurement in the urethra. The urethral pressure increments preceding and following the pressure spike were statistically significantly higher in the mid-urethra than the corresponding bladder pressures. This active urethral pressure generation in the mid-urethra and distal urethra was initiated 200 ms before the bladder pressure began to rise. The pressure in the urethral high pressure zone was higher than the bladder pressure in all cases. Passive pressure transmission to the urethral high pressure zone can take place only insignificantly due to a continuous higher pressure inside the urethra than in the bladder and due to the location of the high pressure zone in the demarcation of the abdominal cavity. It was concluded that the urethral pressure rise in the high pressure zone during stress episodes is mainly generated actively by intra- and/or peri-urethral structures.

Patterns of transmitted HIV drug resistance in Europe vary by risk group

Background

In Europe, a continuous programme (SPREAD) has been in place for ten years to study transmission of drug resistant HIV. We analysed time trends of transmitted drug resistance mutations (TDRM) in relation to the risk behaviour reported.

Methods

HIV-1 patients newly diagnosed in 27 countries from 2002 through 2007 were included. Inclusion was representative for risk group and geographical distribution in the participating countries in Europe. Trends over time were calculated by logistic regression.

Results

From the 4317 patients included, the majority was men-having-sex-with-men -MSM (2084, 48%), followed by heterosexuals (1501, 35%) and injection drug users (IDU) (355, 8%). MSM were more often from Western Europe origin, infected with subtype B virus, and recently infected (<1 year) (p<0.001). The prevalence of TDRM was highest in MSM (prevalence of 11.1%), followed by heterosexuals (6.6%) and IDU (5.1%, p<0.001). TDRM was predominantly ascribed to nucleoside reverse transcriptase inhibitors (NRTI) with a prevalence of 6.6% in MSM, 3.3% in heterosexuals and 2.0% in IDU (p = 0.001). A significant increase in resistance to non- nucleoside reverse transcriptase inhibitors (NNRTIs) and a decrease in resistance to protease inhibitors was observed in MSM (p = 0.008 and p = 0.006, respectively), but not in heterosexual patients (p = 0.68 and p = 0.14, respectively).

Conclusions

MSM showed to have significantly higher TDRM prevalence compared to heterosexuals and IDU. The increasing NNRTI resistance in MSM is likely to negatively influence the therapy response of first-line therapy, as most include NNRTI drugs.

Endothelial cells of the cardiac microvasculature during and after cold cardioplegic ischaemia. Comparison of endothelial and myocyte damage

Ultrastructural changes in endothelial cells of the myocardial microvasculature were studied in 18 patients who underwent aortocoronary bypass surgery under cold ischaemic cardioplegia. Biopsy specimens for electron microscopy were taken from the right atrium before and at the end of aortic cross-clamping and after 20 and 60 min of reperfusion. At the end of the cold ischaemic cardioplegia, the endothelial cells showed reduced numbers of pinocytotic vesicles, moderate intracellular oedema and slight nuclear changes. During reperfusion the endothelial changes became more pronounced and interstitial oedema developed. These changes persisted, or even increased in the first 60 min of reperfusion, in contrast to the myocytic changes, which tended to regress. The endothelial cells of the myocardial microvasculature thus appeared to be more vulnerable than the myocytes to cold ischaemic cardioplegia and reperfusion. Focally reduced blood reperfusion due to endothelial swelling and interstitial oedema did not seem to be the main cause of the focal postischaemic myocytic damage.