The effect of teriparatide compared with risedronate on reduction of back pain in postmenopausal women with osteoporotic vertebral fractures

Summary

The effect of teriparatide and risedronate on back pain was tested, and there was no difference in the proportion of patients experiencing a reduction in back pain between groups after 6 or 18?months. Patients receiving teriparatide had greater increases in bone mineral density and had fewer vertebral fractures.

Introduction

This study aimed to understand the effect of teriparatide in reducing back pain in patients with prevalent back pain and vertebral fracture compared to risedronate.

Methods

In an 18-month randomized, double-blind, double-dummy trial, we investigated the effects of teriparatide (20?μg/day) vs. risedronate (35?mg/week) in postmenopausal women with back pain likely due to vertebral fracture. The primary objective was to compare the proportion of subjects reporting ≥30% reduction in worst back pain severity from baseline to 6?months as assessed by a numeric rating scale in each treatment group. Pre-specified secondary and exploratory outcomes included assessments of average and worst back pain at additional time points, disability and quality of life, bone mineral density, incidence of fractures, and safety.

Results

At 6?months, 59% of teriparatide and 57% of risedronate patients reported ≥30% reduction in worst back pain and there were no differences between groups in the proportion of patients experiencing reduction in worst or average back pain at any time point, disability, or quality of life. There was a greater increase from baseline in bone mineral density at the lumbar spine (p?=?0.001) and femoral neck (p?=?0.02) with teriparatide compared to risedronate and a lower incidence of vertebral fractures at 18?months (4% teriparatide and 9% risedronate; p?=?0.01). Vertebral fractures were less severe (p?=?0.04) in the teriparatide group. There was no difference in the overall incidence of adverse events.

Conclusions

Although there were no differences in back pain-related endpoints, patients receiving teriparatide had greater skeletal benefit than those receiving risedronate.     

Are occult fractures of the hip and pelvic ring mutually exclusive?

We have evaluated retrospectively the relationship of bony injuries seen on 106 consecutive MR scans in elderly patients of a mean age of 81.4 years (67 to 101) who were unable to bear weight after a low-energy injury. There were no visible fractures on plain radiographs of the hip but eight patients (7.5%) had fractures of the pubic ramus. In 43 patients (40.5%) MRI revealed a fracture of the femoral neck and in 26 (24.5%) there was a fracture of a pubic ramus. In 17 patients (16%) MRI showed an occult sacral fracture and all of these had a fracture of the pubic ramus. No patient with a fracture of the femoral neck had an associated fracture of the pelvic ring or vice versa. Occult fracture of the hip and of the pelvic ring appear to be mutually exclusive and if an acute fracture of the pubic ramus is diagnosed radiologically further investigations are not needed to rule out an occult fracture of the hip.     

Limb ischaemia in a Stanford B aortic dissection into an abdominal aortic aneurysm

Aortic dissection presenting with acute lower limb ischaemia is not uncommon. However, stanford B dissection into a pre-existing abdominal aortic aneurysm resulting in bilateral lower limb ischaemia has not been reported in the literature. This patient underwent unsuccessful revascularisation of the lower limbs with an axillo-bifemoral bypass procedure.     

Mutations in the VHL gene in sporadic apparently congenital polycythemia

The congenital polycythemic disorders with elevated erythropoietin (Epo) have been until recently an enigma, and abnormality in the hypoxia-sensing pathway has been hypothesized as a possible mechanism. The tumor suppressor von Hippel-Lindau (VHL) participates in the hypoxia-sensing pathway, as it binds to the proline-hydroxylated form of the hypoxia-inducible factor 1alpha (HIF-1alpha) and mediates its ubiquitination and proteosomal degradation. The loss of VHL function may result in the accumulation of HIF-1alpha and overproduction of HIF-1 downstream target genes including Epo. VHL syndrome is an autosomal dominant disorder predisposing to the development of tumors, due to inherited mutations in the VHL gene. Some rare patients with VHL syndrome have polycythemia, which has been attributed to Epo production by a tumor. It was recently found that homozygosity for the VHL Arg200Trp mutation is the cause of Chuvash polycythemia, an autosomal recessive polycythemic disorder characterized by elevated serum Epo and hypersensitivity of erythroid cells to Epo. We evaluated the role of VHL in 8 children with a history of polycythemia and an elevated serum Epo level and found 3 different germline VHL mutations in 4 of them. One child was homozygous for the Arg200Trp VHL mutation, and another compound heterozygous for the Arg200Trp and the Val130Leu mutations. Two children (siblings) were heterozygous for an Asp126Tyr mutation, one of them fulfilling some criteria of VHL syndrome. We propose that mutations of the VHL gene represent an important cause of pediatric sporadic polycythemias with an inappropriately high serum Epo concentration.     

Acquisition of urine, kidney and submandibular gland epidermal growth factor responsiveness to thyroxine administration in neonatal mice

Thyroxine (T4) administration to newborn mice on days 0-6 produced no measurable changes of submandibular gland (SMG) or kidney epidermal growth factor (EGF) concentrations on day 7, compared with vehicle-treated control pups. By contrast, this regimen caused a large increase in urine EGF levels. The effects of three T4 injection regimens (on days 0-6, 7-14 and 0-14) were then studied on day 15. The 0-14 and 7-14 day-regimens elicited large increments in urine, SMG and kidney EGF concentration, the 0-14 day-regimen having the greatest effect. The 0-6 day-regimen had no effect on SMG and kidney EGF concentrations on day 15 but did increase urine EGF. In summary, urine EGF responsiveness to T4 is present during the first week of life, but SMG and kidney EGF responsiveness develops only in the second week. Administration of T4 appears to accelerate the normal ontogeny of urine, kidney and SMG EGF.     

Antiretroviral therapy adherence measurement in non-clinical settings in South India

Optimal adherence to antiretroviral therapy (ART) is key to viral suppression, but may be impeded by psychosocial consequences of HIV-infection such as stigma and depression. Measures of adherence in India have been examined in clinic populations, but little is known about the performance of these measures outside clinical settings. We conducted a cross-sectional study of 151 Tamil-speaking people living with HIV/AIDS (PLHA) in India recruited through HIV support networks and compared single item measures from the Adult AIDS Clinical Trial Group (AACTG) scale, a visual analog scale (VAS), and a question on timing of last missed dose. Depression was measured using the Major Depression Inventory (MDI) and HIV-related stigma was measured using an adaptation of the Berger Stigma Scale. Mean age was 35.6 years (SD ± 5.9); 55.6% were male; mean MDI score was 11.9 (SD ± 9.1); and mean stigma score was 67.3 (SD ± 12.0). Self-reported perfect adherence (no missed doses) was 93.3% using the AACTG item, 87.1% using last missed dose, and 83.8% using the VAS. The measures had moderate agreement with each other (kappa 0.45–0.57). Depression was associated with lower adherence irrespective of adherence measure used, and remained significantly associated in multivariable analyses adjusting for age and marital status. Stigma was not associated with adherence irrespective of the measure used. The VAS captured the greatest number of potentially non-adherent individuals and may be useful for identifying PLHA in need of adherence support. Given the consistent and strong association between poorer adherence and depression, programs that jointly address adherence and mental health for PLHA in India may be more effective than programs targeting only one.     

The Association Between Opioid Use and Outcomes in Infants Undergoing Pyloromyotomy

PurposeThe purpose of this study was to describe the frequency and variation of opioid use across hospitals in infants undergoing pyloromyotomy and to determine the impact of opioid use on postoperative outcomes.MethodsA retrospective cohort study (2005–2015) was conducted by using the Pediatric Health Information System (PHIS) database, including infants (aged <6 months) with pyloric stenosis who underwent pyloromyotomy. Infants with significant comorbidities were excluded. Opioid use was classified as a patient receiving at least 1 opioid medication during his or her hospital stay and categorized as preoperative, day of surgery, or postoperative (≥1 day after surgery). Outcomes included prolonged hospital length of stay (LOS; ≥3 days) and readmission within 30 days.FindingsOverall, 25,724 infants who underwent pyloromyotomy were analyzed. Opioids were administered to 6865 (26.7%) infants, with 1385 (5.4%) receiving opioids postoperatively. In 2015, there was significant variation in frequency of opioid use by hospital, with 0%–81% of infants within an individual hospital receiving opioids (P < 0.001). Infants only receiving opioids on the day of surgery exhibited decreased odds of prolonged hospital LOS (odds ratio [OR], 0.85; 95% CI, 0.78–0.92). Infants who received an opioid on both the day of surgery and postoperatively exhibited increased odds of a prolonged hospital LOS (OR, 1.71; 95% CI, 1.33–2.20). Thirty-day readmission was not associated with opioid use (OR, 1.03; 95% CI, 0.93–1.14).ImplicationsThere is national variability in opioid use for infants undergoing pyloromyotomy, and postoperative opioid use is associated with prolonged hospital stay. Nonopioid analgesic protocols may warrant future investigation.     

A Non-Radioactive DAPI-based High-Throughput In Vitro Assay to Assess Plasmodium falciparum Responsiveness to Antimalarials��Increased Sensitivity of P. falciparum to Chloroquine in Senegal

The spread of Plasmodium falciparum drug resistance is outpacing new antimalarial development and compromising effective malaria treatment. Combination therapy is widely implemented to prolong the effectiveness of currently approved antimalarials. To maximize utility of available drugs, periodic monitoring of drug efficacy and gathering of accurate information regarding parasite-sensitivity changes are essential. We describe a high-throughput, non-radioactive, field-based assay to evaluate in vitro antimalarial drug sensitivity of P. falciparum isolates from 40 Senegalese patients. Compared with earlier years, we found a significant decrease in chloroquine in vitro and in genotypic resistances (> 50% and > 65%, respectively, in previous studies) with only 23% of isolates showing resistance. This is possibly caused by a withdrawal of chloroquine from Senegal in 2002. We also found a range of artemisinin responses. Prevalence of drug resistance is dynamic and varies by region. Therefore, the implementation of non-radioactive, robust, high-throughput antimalarial sensitivity assays is critical for defining region-specific prophylaxis and treatment guidelines.Plasmodium falciparum, which causes the most virulent human malaria, is responsible for approximately one million deaths annually. Malaria related morbidity and mortality in sub-Saharan Africa presents a significant obstacle for economic development in this part of the world.^1,2 Although a number of chemotherapeutic options are available for treating P. falciparum malaria, the rapid spread of drug resistance has marginalized the utility of many of these drugs. Chloroquine (CQ), quinine (QN), pyrimethamine, amodiaquine (AMQ), and artemisinin (ART) are among the most effective antimalarial agents. The latter two have been used in combination in many malaria endemic regions to thwart the emergence of drug resistance.³ In fact, the World Health Organization recommends the use of ART-based combination therapy (ACT) as a first-line regimen throughout much of Africa.⁴ However, monotherapy with ART and its derivatives has caused the emergence of parasites that show decreased sensitivity to these drugs, which is reflected in the higher IC₅₀ values of some P. falciparum clinical isolates.^5,6 Although clinical resistance to ART has not been adequately defined and reported, these decreased sensitivities may be the harbinger of clinical resistance. Periodic surveillance of drug efficacy through in vitro drug-sensitivity assays is essential for optimal selection of drug combinations, which will ensure successful administration of antimalarial treatment.High-throughput methods that enable analyses of drug responsiveness of clinical isolates from different countries where malaria is endemic are essential to define antimalarial treatment regimens in those regions. For example, ACT is routinely and widely used for managing most malaria infections, sulfadoxine-pyrimethamine is still used for intermittent preventative treatment in pregnancy, and QN remains an important option for parenteral use in severe disease.⁴ In addition, a wide variation in drug sensitivity may be present even within the same country,⁷ and thus, drug-sensitivity testing would be needed for each geographically distinct region. Moreover, such high-throughput methods will allow screening of lead compounds that could potentially be developed into novel antimalarials.Herein, we describe the field implementation of a non-radioactive, high-throughput assay to evaluate drug sensitivity on ex vivo isolates of P. falciparum collected from infected Senegalese patients. Previously, the only means of evaluating inhibition of parasite proliferation entailed microscopic examination of blood smears stained with modified Wright-Giemsa or use of the [³H]-hypoxanthine incorporation assay.⁸ The assays are either laborious or require the use of radioactive isotopes, whose safe disposal is difficult in a resource-limited setting. More recently, methods for quantifying parasite histidine-rich protein-2 (HRP-2) as well as non-radioactive fluorescence-based methods using SYBR green and 4–6-diamidino-2-phenylindole (DAPI) that measure parasite DNA have been developed.^9–11 We have adapted the DAPI-based method to evaluate drug sensitivity of ex vivo P. falciparum parasite cultures, thus directly assessing parasite samples collected from patients under field laboratory conditions in Senegal.We examined the drug-sensitivity profiles of P. falciparum parasites derived from Senegalese patients presenting during transmission season in the fall of 2007 to the Anti-Parasite Service in Thiès (SLAP), a city ~75 km southeast of Dakar, against a panel of antimalarial agents. In this region, malaria transmission is perennial and hypoendemic with an increase in cases during the end of the rainy season from September to December.¹² Approximately one-third of all outpatient consultations and 20–30% of mortality in healthcare facilities in Senegal can be attributed to infection with P. falciparum. CQ was recommended as the first-line malaria therapy in Senegal until 2002. However, in 2003, the Senegalese Ministry of Health altered the national treatment policy to include ACT using artesunate, a more soluble derivative of ART, plus AMQ as the first-line antimalarial regimen.Consenting outpatients with clinical signs suggestive of mild malaria and a positive Giemsa-stained thick film for P. falciparum were identified and enrolled from SLAP. Patients presenting with fever or those who had a history of fever and symptoms indicative of malaria were enrolled. The study protocol was approved by the Ethics Committee of the Ministry of Health in Senegal and the Human Subject Committee of the Harvard School of Public Health.Before the start of the transmission season, microtiter plates were pre-loaded with antimalarial drug dilutions (serial dilutions of CQ [0.02–400 nM], AMQ [0.02–20 μM], ART [3.12–35 nM], and QN [234.37–75 μM] and stored at −20°C until needed. Blood was collected from patients and transported on ice to the central laboratory. Only samples with 0.3% parasitemia or greater were used for the study. Inasmuch as this may introduce some bias, we were unable to use our method to obtain standard threshold 50% inhibitory concentration (IC₅₀) values for isolates with lower parasitemias. Packed erythrocytes were washed twice with RPMI (pH 7.4). The hematocrit of all samples was set to 2%, and samples with parasitemia greater than 1% were adjusted to 0.5–1.0% in complete medium using standard tissue-culture media.¹⁰ The cell suspension (180 μL per well) was dispensed into the thawed, pre-loaded, 96-well microtiter plates. The plates were incubated at 37°C in a gas environment of 5% CO₂, 1% O₂, and 94% N₂ for 72 hours. Smears prepared from zero drug wells were stained with Giemsa to ensure parasite growth at 72 hours. Samples that did not show any parasite growth in culture were eliminated from the subsequent analyses. At the end of the assay, the plates were frozen at −20°C. The microtiter plates were then thawed at room temperature and centrifuged, and media were aspirated with care to avoid disturbing the red cell pellet. The fluorochrome mixture was prepared as previously described¹⁰ and dispensed in each well at a final dilution of 1:100,000 of DAPI (5 mg/mL stock; Molecular Probes, Inc., Eugene, OR). The microtiter plates were then incubated in the dark for 30 minutes and centrifuged at 4,000 rpm for 10 minutes. Excess fluorochrome mixture was aspirated, and 30 μL of 1× phosphate buffered saline (PBS) was dispensed into each well. The microtiter plates were read using a Fluoroskan plate reader (ThermoFisher Scientific, Milford, MA) with excitation and emission wavelengths of 355 nm and 460 nm, respectively. IC₅₀ values were calculated by non-linear regression analysis (GraphPad Prism, La Jolla, CA). Each antimalarial compound was evaluated in duplicate.Parasite resistance to CQ, QN, and AMQ was defined based on standard threshold IC₅₀ values, above which parasites are classified as resistant (13

Table 1

Median IC₅₀ values of field isolates from Senegal for a panel of antimalarials