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David Wright

Publications and source records attributed to David Wright.

12 recordsLinked to original sources
PubMed2025

Polygenic Risk Scores for Preeclampsia Prediction Beyond Gold-Standard Clinical Models in Multiethnic Populations.

BACKGROUND: Preeclampsia is a major cause of maternal and fetal mortality and morbidity. Early risk stratification enables timely preventative therapy in high-risk women. Polygenic risk scores (PGS) improve prediction in complex diseases, but their added value for preeclampsia remains unclear, particularly in comparison to gold-standard first-trimester prediction models and across non-European ancestries. METHODS: We evaluated the performance of both a preeclampsia and systolic blood pressure PGS in 2 prospective pregnancy cohorts with detailed phenotyping: the Fetal Medicine Foundation study (n=5207; 2127 cases) and the Pregnancy Outcome Prediction study (n=3659; 228 cases). Risk models included (1) clinical factors; (2) clinical factors plus PGS; (3) advanced model including first-trimester mean arterial pressure, PAPP-A (pregnancy-associated plasma protein-A), and uterine artery pulsatility index; and (4) advanced model plus PGS. Discriminative performance, measured by the area under the receiver operating characteristic curve, was assessed overall and by ancestry. RESULTS: The preeclampsia PGS was independently associated with preeclampsia (odds ratio per SD, 1.24 [95% CI, 1.17-1.31]; P<0.001). It modestly improved prediction over clinical models (area under the receiver operating characteristic curve 0.746 versus 0.750; P=0.017) but not over the advanced model (area under the receiver operating characteristic curve 0.817 versus 0.818; P=0.326). The systolic blood pressure PGS showed stronger performance, improving prediction over both models in women of European ancestry. No improvement was observed with either score in women of African ancestry. CONCLUSIONS: PGSs for preeclampsia and SBP provide modest added predictive value beyond clinical risk factors in European ancestry women. Limited utility in African ancestry women reflects underrepresentation in the genome-wide association studies used to develop current scores. As cohort sizes grow and models are refined, PGSs may become important tools for equitable risk stratification in maternal health.

Adult↗
PubMed2003

How well do midwives estimate the date of delivery?

OBJECTIVE: to compare expected date of delivery (EDD) and gestational age (GA) obtained by midwives with those calculated using the Confidential Enquiry into Stillbirths and Death in Infancy (CESDI) recommended formula. DESIGN: retrospective study of obstetric records and prospective study of clinical cases examined by multiple midwives. SETTING: postnatal wards, Maternity Unit, Plymouth, Devon, UK. PARTICIPANTS: two studies were performed. The first was a retrospective analysis of 115 sets of obstetric records. The second, a prospective study which included five clinical cases and 19 qualified midwives whose experience ranged from six months to 25 years. FINDINGS: in the retrospective study, 68 (59%) of the 115 obstetric case notes had sufficient information to apply the CESDI formula. The midwives'calculated EDD was interpreted to a GA and 35 (52.5%) agreed to within three days of the GA derived from the CESDI formula EDD. In the prospective study, the midwives' calculation of EDD was in good agreement with the CESDI formula in cases where last menstrual period (LMP) was known and menstrual cycle was 28 days with 17 (90%) of the 19 midwives providing the EDD to within three days of the CESDI formula. In the clinical case where LMP was known but menstrual cycle length was 33 days only two (10%) of the 19 calculated the EDD within three days of the CESDI formula. KEY CONCLUSIONS: when LMP is known and the cycle length is 28 days, midwives produce results consistent with the CESDI formula. However, when the menstrual cycle differs from 28 days or LMP is unknown, inaccurate or ambiguous and obstetric ultrasound scan (USS) information is used to calculate the EDD, the midwives show varying degrees of departure from the CESDI formula. Further, we found that the midwives tended to produce underestimates when calculating GA from EDD. This bias occurs across the range of gestations covered, including early gestations when such biases may have more important medical implications. IMPLICATIONS FOR PRACTICE: midwives' calculation of EDD and estimation of GA showed both random and systematic errors; in some cases, the errors were so large that they may have important medical consequences. If the CESDI-recommended formula for calculating EDD were used there would be improved accuracy and reliability of EDD and the calculation of GA.

Clinical Competence↗
PubMed2003

How much are patients willing to pay to avoid intraoperative awareness?

STUDY OBJECTIVE: To determine how much patients are willing to pay to avoid intraoperative awareness? DESIGN: Observational study SETTING: University-affiliated metropolitan hospital. PATIENTS: 60 patients who completed a questionnaire (39 F, 21 M). The mean age was 43 years and the median household income range of 45,000-60,000 US dollars. INTERVENTIONS: Patients completed an interactive computer-generated questionnaire on the value of preventing intraoperative awareness and their willingness to pay for a "depth of anesthesia" monitor. Their willingness to pay for the prevention of postoperative pain, nausea and vomiting, postoperative grogginess, and sleepiness was also determined as a means of comparison. MEASUREMENTS AND MAIN RESULTS: Patients were willing to pay (WTP) 34 US dollars, 10 US dollars to 42 US dollars (median, interquartile range) for a monitor that would assist an anesthesia care provider assess the depth of anesthesia in an effort to avoid awareness. This increased to 43 US dollars, 20 US dollars to 77 US dollars (p < 0.0,001) (median, interquartile range), if the insurance company was making the payment and the WTP value only decreased minimally to 33 US dollars if the incidence of awareness was reduced 10-fold. CONCLUSION: The incidence of intraoperative awareness and WTP value for monitoring awareness have a nonlinear relationship (a risk averse utility function), which suggests that patients assign an intrinsic base value for a rare or very rare possibility of an event. Other healthcare economic analyses (such as cost effectiveness) do not take this factor into account and assume a linear value relationship (i.e., if something occurs ten times less frequently, it has ten times less value). IMPLICATION: The median value for patients' WTP for a monitor that might prevent awareness under anesthesia was 34 US dollars given an incidence of 5/1,000 cases. The incidence of awareness and WTP value have a nonlinear relationship suggesting that patients assign an intrinsic base value for the possibility of awareness.

Adult↗
PubMed2002

The high-speed Hydra-Plus-One system for automated high-throughput protein crystallography.

An automated high-throughput dispenser has been developed for the setup of protein crystallization trials by vapor diffusion or Microbatch methods. The Hydra-Plus-One is composed of a Hydra-PP system equipped with a motorized XYZ-platform, 96 precision glass syringes and a single-channel microsolenoid dispenser, which transfers 100 nl-50 micro l of protein solution with an accuracy of > 90% at a speed of 60s per 96 wells. Up to 300 micro l of premixed cocktails can be aspirated with the 96-syringe-assembly and dispensed into reservoir and droplet wells within 60s. The Hydra-Plus-One combines high precision, reliability and speed in a cost-effective high-throughput system ideally suited for protein crystallization

Bacterial Proteins↗
PubMed2002

HIV seroconverting donors delay their return: screening test implications.

BACKGROUND: The yield of HIV p24 antigen testing implemented in March 1996 has been lower than projected. One possible explanation is that HIV seroconverting donors delay their return because of the recent practice of risk behaviors and/or signs and symptoms associated with primary infection. STUDY DESIGN AND METHODS: From a database of 6.8-million allogeneic donations collected at five U.S. blood centers from 1991 to 1997, 49 HIV, 21 HCV, 32 HTLV, and 44 HBsAg seroconverters with at least three donations were identified. A statistical method was developed to investigate whether the time between a donor's last negative donation and their positive donation was significantly longer than expected based on their previous return history. RESULTS: HIV seroconverters returned on average 42 percent later than expected (p < 0.01). Although not significant, HCV seroconverters donated on average 43 percent earlier than expected. HTLV and HBsAg seroconverters did not appear to change their donation pattern around the time of seroconversion. Sixty-three percent of the HIV seroconverters later acknowledged practicing a high-risk behavior. CONCLUSIONS: HIV seroconverters delay their return around the time of seroconversion and are thus less likely to be recently infected. Unique among HIV seroconverters, this observation provides a possible explanation for the lower than expected yield of HIV p24 antigen testing and suggests that NAT may have a similar low yield.

Blood Donors↗
PubMed2002

Five-year follow-up of patients undergoing laparoscopic or open groin hernia repair: a randomized controlled trial.

OBJECTIVE: To compare laparoscopic with open hernia repair in a randomized clinical trial at a median follow-up of 5 years. SUMMARY BACKGROUND DATA: Follow-up of patients in clinical trials evaluating laparoscopic hernia repair has been short. METHODS: Of 379 consecutive patients admitted for surgery under the care of one surgeon, 300 were randomized to totally extraperitoneal hernia repair or open repair, with the open operation individualized to the patient's age and hernia type. All patients, both randomized and nonrandomized, were followed up by clinical examination annually by an independent observer. RESULTS: Recurrence rates were similar for both randomized groups. In 1 of the 79 nonrandomized patients, a recurrent hernia developed. Groin or testicular pain was the most common symptom on follow-up of randomized patients. The most common reason for reoperation was development of a contralateral hernia, which was noted in 9% of patients; 11% of all patients died on follow-up, mainly as a result of cardiovascular disease or cancer. CONCLUSIONS: These data show a similar outcome for laparoscopic and open hernia repair, and both procedures have a place in managing this common problem.

Aged↗
PubMed2002

Hemodynamic aspects of Alzheimer's disease.

Neuroradiological functional imaging techniques demonstrate the patterns of hypoperfusion and hypometabolism that are thought to be useful in the differential diagnosis of Alzheimer's disease (AD) from other dementing disorders. Besides the distribution patterns of perfusion or energy metabolism, vascular transit time (VTT), vascular reactivity (VR), and oxygen extraction fraction (OEF), which can be measured with positron emission tomography (PET), provide hemodynamic aspects of brain pathophysiology. In order to evaluate the hemodynamic features of AD, PET studies were carried out in 20 patients with probable AD and 20 patients with vascular dementia (VaD). The PET findings were not included in their diagnostic process of AD. Using oxygen-15-labeled compounds, cerebral blood flow (CBF), cerebral metabolic rate of oxygen (CMRO(2)), OEF, cerebral blood volume, and VTT were measured quantitatively during resting state. To evaluate VR, CBF was also measured during CO(2) inhalation. There was a significant increase in OEF in and around the parietotemporal cortices, but both VTT and VR were well preserved in patients with AD. By contrast, VR was markedly depressed and VTT was mildly prolonged in patients with VaD. Thus, from the hemodynamic point of view, the preservation of vascular reserve may be a distinct difference between AD and VaD. Furthermore, this indicates a hemodynamic integrity of the vasculature in the level of arterioles in AD.

Aged↗
PubMed2002

Medical devices on trial, Part I.

This is the first of a two-part article exploring the place that clinical research plays in today's medical device industry. Part I looks at the differences in development processes between drugs and devices and examines future trends for increased requirements for clinical data in the device sector.

Biomedical Research↗
PubMedDate not supplied

Medication administration in nursing homes.

AIM: To describe the difficulties faced when administering oral medication to patients with swallowing difficulties in nursing homes, the methods that are used to overcome these difficulties and their appropriateness. METHOD: A self-administered questionnaire was given to all participants (n = 763) at eight regional study days for nurses employed in independent nursing homes. The questionnaire included sections on respondent and nursing home demographics, extent of and methods used to overcome swallowing difficulties, experience of overcoming swallowing difficulties and nurses' opinions on the ease of changing prescriptions to liquid formulations. RESULTS: Of 763 questionnaires, 540 (70.8 per cent) were returned completed. On average 15 per cent of all residents had difficulty swallowing tablets and capsules, 5 per cent regularly spat out their medication and 1 per cent hid it. Hiding medication in food was reported by 56.5 per cent (n = 305) of respondents, 26.9 per cent (n = 145) omitted the dose, 61.3 per cent (n = 331) crushed or opened medication before administration and 87.6 per cent (n = 473) obtained liquid alternatives. Crushing or opening of medication (unlicensed administration) took place in more than 80 per cent of all nursing homes on at least a weekly basis. The majority of nurses (n = 487, 90.2 per cent) would not be reluctant to ask the prescriber for a liquid alternative, however, 58 per cent (193 out of 333) stated that the prescriber might recommend that medicines be crushed or opened, and cost was stated to be a consideration in this process by 62 per cent (n = 335) of nurses. CONCLUSION: The crushing or opening of medication results in unlicensed administration. Liability lies solely with the nurse if the action was unauthorised and is shared with the prescriber if it had been authorised. With the availability of most oral medicines as a liquid formulation, the majority of reported crushing or opening that is taking place is unnecessary. In many instances this is because of prescriber reluctance to change the prescription. Nurses choosing to administer medication via a non-licensed method should ensure that all other avenues have been considered and appropriate advice sought. Where unlicensed administration is authorised by the prescriber, a written and signed record of this should be obtained.

Administration, Oral↗