Welcome to Hirsla, Landspítali University Hospital research archive

Hirsla is an open access repository, designed as a place to store, index, preserve and redistribute in digital format scholarly work of Landspitali employees. (A/H1N1)

  • Global Landscape Review of Serotype-Specific Invasive Pneumococcal Disease Surveillance among Countries Using PCV10/13: The Pneumococcal Serotype Replacement and Distribution Estimation (PSERENADE) Project.

    Deloria Knoll, Maria; Bennett, Julia C; Garcia Quesada, Maria; Kagucia, Eunice W; Peterson, Meagan E; Feikin, Daniel R; Cohen, Adam L; Hetrich, Marissa K; Yang, Yangyupei; Sinkevitch, Jenna N; et al. (MDPI, 2021-04-02)
    Serotype-specific surveillance for invasive pneumococcal disease (IPD) is essential for assessing the impact of 10- and 13-valent pneumococcal conjugate vaccines (PCV10/13). The Pneumococcal Serotype Replacement and Distribution Estimation (PSERENADE) project aimed to evaluate the global evidence to estimate the impact of PCV10/13 by age, product, schedule, and syndrome. Here we systematically characterize and summarize the global landscape of routine serotype-specific IPD surveillance in PCV10/13-using countries and describe the subset that are included in PSERENADE. Of 138 countries using PCV10/13 as of 2018, we identified 109 with IPD surveillance systems, 76 of which met PSERENADE data collection eligibility criteria. PSERENADE received data from most (n = 63, 82.9%), yielding 240,639 post-PCV10/13 introduction IPD cases. Pediatric and adult surveillance was represented from all geographic regions but was limited from lower income and high-burden countries. In PSERENADE, 18 sites evaluated PCV10, 42 PCV13, and 17 both; 17 sites used a 3 + 0 schedule, 38 used 2 + 1, 13 used 3 + 1, and 9 used mixed schedules. With such a sizeable and generally representative dataset, PSERENADE will be able to conduct robust analyses to estimate PCV impact and inform policy at national and global levels regarding adult immunization, schedule, and product choice, including for higher valency PCVs on the horizon. Keywords: global; invasive pneumococcal disease; pneumococcal conjugate vaccines; pneumococcal meningitis; surveillance.
  • Serotype Distribution of Remaining Pneumococcal Meningitis in the Mature PCV10/13 Period: Findings from the PSERENADE Project.

    Garcia Quesada, Maria; Yang, Yangyupei; Bennett, Julia C; Hayford, Kyla; Zeger, Scott L; Feikin, Daniel R; Peterson, Meagan E; Cohen, Adam L; Almeida, Samanta C G; Ampofo, Krow; et al. (MDPI, 2021-04-01)
    Pneumococcal conjugate vaccine (PCV) introduction has reduced pneumococcal meningitis incidence. The Pneumococcal Serotype Replacement and Distribution Estimation (PSERENADE) project described the serotype distribution of remaining pneumococcal meningitis in countries using PCV10/13 for least 5-7 years with primary series uptake above 70%. The distribution was estimated using a multinomial Dirichlet regression model, stratified by PCV product and age. In PCV10-using sites (N = 8; cases = 1141), PCV10 types caused 5% of cases <5 years of age and 15% among ≥5 years; the top serotypes were 19A, 6C, and 3, together causing 42% of cases <5 years and 37% ≥5 years. In PCV13-using sites (N = 32; cases = 4503), PCV13 types caused 14% in <5 and 26% in ≥5 years; 4% and 13%, respectively, were serotype 3. Among the top serotypes are five (15BC, 8, 12F, 10A, and 22F) included in higher-valency PCVs under evaluation. Other top serotypes (24F, 23B, and 23A) are not in any known investigational product. In countries with mature vaccination programs, the proportion of pneumococcal meningitis caused by vaccine-in-use serotypes is lower (≤26% across all ages) than pre-PCV (≥70% in children). Higher-valency PCVs under evaluation target over half of remaining pneumococcal meningitis cases, but questions remain regarding generalizability to the African meningitis belt where additional data are needed.
  • Fetal descent in nulliparous women assessed by ultrasound: a longitudinal study.

    Hjartardóttir, Hulda; Lund, Sigrún H; Benediktsdóttir, Sigurlaug; Geirsson, Reynir T; Eggebø, Torbjørn M; 1Department of Obstetrics and Gynecology, Landspitali - The National University Hospital of Iceland, Reykjavik, Iceland; Faculty of Medicine, University of Iceland, Reykjavik, Iceland. Electronic address: huldahja@landspitali.is. 2deCODE genetics, Reykjavik, Iceland. 3Department of Obstetrics and Gynecology, Landspitali - The National University Hospital of Iceland, Reykjavik, Iceland; Faculty of Medicine, University of Iceland, Reykjavik, Iceland. 4National Center for Fetal Medicine, Department of Obstetrics and Gynecology, St. Olavs Hospital, Trondheim University Hospital, Trondheim, Norway; Department of Obstetrics and Gynecology, Stavanger University Hospital, Stravanger, Norway; Institute of Clinical and Molecular Medicine, Norwegian University of Science and Technology, Trondheim, Norway. (Elsevier, 2020-10-08)
    Background: Ultrasound measurements offer objective and reproducible methods to measure the fetal head station. Before these methods can be applied to assess labor progression, the fetal head descent needs to be evaluated longitudinally in well-defined populations and compared with the existing data derived from clinical examinations. Objective: This study aimed to use ultrasound measurements to describe the fetal head descent longitudinally as labor progressed through the active phase in nulliparous women with spontaneous onset of labor. Study design: This was a single center, prospective cohort study at the Landspitali - The National University Hospital of Iceland, Reykjavik, Iceland, from January 2016 to April 2018. Nulliparous women with a single fetus in cephalic presentation and spontaneous labor onset at a gestational age of ≥37 weeks, were eligible. Participant inclusion occurred during admission for women with an established active phase of labor or at the start of the active phase for women admitted during the latent phase. The active phase was defined as an effaced cervix dilated to at least 4 cm in women with regular contractions. According to the clinical protocol, vaginal examinations were done at entry and subsequently throughout labor, paired each time with a transperineal ultrasound examination by a separate examiner, with both examiners being blinded to the other's results. The measurements used to assess the fetal head station were the head-perineum distance and angle of progression. Cervical dilatation was examined clinically. Results: The study population comprised 99 women. The labor patterns for the head-perineum distance, angle of progression, and cervical dilatation differentiated the participants into 75 with spontaneous deliveries, 16 with instrumental vaginal deliveries, and 8 cesarean deliveries. At the inclusion stage, the cervix was dilated 4 cm in 26 of the women, 5 cm in 30 of the women, and ≥6 cm in 43 women. One cesarean and 1 ventouse delivery were performed for fetal distress, whereas the remaining cesarean deliveries were conducted because of a failure to progress. The total number of examinations conducted throughout the study was 345, with an average of 3.6 per woman. The ultrasound-measured fetal head station both at the first and last examination were associated with the delivery mode and remaining time of labor. In spontaneous deliveries, rapid head descent started around 4 hours before birth, the descent being more gradual in instrumental deliveries and absent in cesarean deliveries. A head-perineum distance of 30 mm and angle of progression of 125° separately predicted delivery within 3.0 hours (95% confidence interval, 2.5-3.8 hours and 2.4-3.7 hours, respectively) in women delivering vaginally. Although the head-perineum distance and angle of progression are independent methods, both methods gave similar mirror image patterns. The fetal head station at the first examination was highest for the fetuses in occiput posterior position, but the pattern of rapid descent was similar for all initial positions in spontaneously delivering women. Oxytocin augmentation was used in 41% of women; in these labors a slower descent was noted. Descent was only slightly slower in the 62% of women who received epidural analgesia. A nonlinear relationship was observed between the fetal head station and dilatation. Conclusion: We have established the ultrasound-measured descent patterns for nulliparous women in spontaneous labor. The patterns resemble previously published patterns based on clinical vaginal examinations. The ultrasound-measured fetal head station was associated with the delivery mode and remaining time of labor. Keywords: angle of progression; cesarean delivery; fetal head position; fetal head station; head-perineum distance; transabdominal ultrasound; transperineal ultrasound.
  • Changes in Invasive Pneumococcal Disease Caused by Serotype 1 Following Introduction of PCV10 and PCV13: Findings from the PSERENADE Project.

    Bennett, Julia C; Hetrich, Marissa K; Garcia Quesada, Maria; Sinkevitch, Jenna N; Deloria Knoll, Maria; Feikin, Daniel R; Zeger, Scott L; Kagucia, Eunice W; Cohen, Adam L; Ampofo, Krow; et al. (MDPI, 2021-03-27)
    Streptococcus pneumoniae serotype 1 (ST1) was an important cause of invasive pneumococcal disease (IPD) globally before the introduction of pneumococcal conjugate vaccines (PCVs) containing ST1 antigen. The Pneumococcal Serotype Replacement and Distribution Estimation (PSERENADE) project gathered ST1 IPD surveillance data from sites globally and aimed to estimate PCV10/13 impact on ST1 IPD incidence. We estimated ST1 IPD incidence rate ratios (IRRs) comparing the pre-PCV10/13 period to each post-PCV10/13 year by site using a Bayesian multi-level, mixed-effects Poisson regression and all-site IRRs using a linear mixed-effects regression (N = 45 sites). Following PCV10/13 introduction, the incidence rate (IR) of ST1 IPD declined among all ages. After six years of PCV10/13 use, the all-site IRR was 0.05 (95% credibility interval 0.04-0.06) for all ages, 0.05 (0.04-0.05) for <5 years of age, 0.08 (0.06-0.09) for 5-17 years, 0.06 (0.05-0.08) for 18-49 years, 0.06 (0.05-0.07) for 50-64 years, and 0.05 (0.04-0.06) for ≥65 years. PCV10/13 use in infant immunization programs was followed by a 95% reduction in ST1 IPD in all ages after approximately 6 years. Limited data availability from the highest ST1 disease burden countries using a 3+0 schedule constrains generalizability and data from these settings are needed.
  • Vitamin D status and association with gestational diabetes mellitus in a pregnant cohort in Iceland.

    Magnusdottir, Kristin S; Tryggvadottir, Ellen A; Magnusdottir, Ola K; Hrolfsdottir, Laufey; Halldorsson, Thorhallur I; Birgisdottir, Bryndis E; Hreidarsdottir, Ingibjorg T; Hardardottir, Hildur; Gunnarsdottir, Ingibjorg; 1Unit for Nutrition Research, Landspitali University Hospital and Faculty of Food Science and Nutrition, University of Iceland, Reykjavik, Iceland. 2Institution of Health Science Research, University of Akureyri and Akureyri Hospital, Akureyri, Iceland. 3Centre for Fetal Programming, Department of Epidemiology Research, Statens Serum Institut, Copenhagen, Denmark. 4Department of Obstetrics and Gynecology, Landspitali University Hospital, Reykjavík, Iceland. 5Faculty of Medicine, University of Iceland, Reykjavík, Iceland. (Swedish Nutrition Foundation, 2021-03-23)
    Background: Vitamin D deficiency has been associated with an increased risk of gestational diabetes mellitus (GDM), one of the most common pregnancy complications. The vitamin D status has never previously been studied in pregnant women in Iceland. Objective: The aim of this research study was to evaluate the vitamin D status of an Icelandic cohort of pregnant women and the association between the vitamin D status and the GDM incidence. Design: Subjects included pregnant women (n = 938) who attended their first ultrasound appointment, during gestational weeks 11-14, between October 2017 and March 2018. The use of supplements containing vitamin D over the previous 3 months, height, pre-pregnancy weight, and social status were assessed using a questionnaire, and blood samples were drawn for analyzing the serum 25‑hydroxyvitamin D (25OHD) concentration. Information regarding the incidence of GDM later in pregnancy was collected from medical records. Results: The mean ± standard deviation of the serum 25OHD (S-25OHD) concentration in this cohort was 63±24 nmol/L. The proportion of women with an S-25OHD concentration of ≥ 50 nmol/L (which is considered adequate) was 70%, whereas 25% had concentrations between 30 and 49.9 nmol/L (insufficient) and 5% had concentrations < 30 nmol/L (deficient). The majority of women (n = 766, 82%) used supplements containing vitamin D on a daily basis. A gradual decrease in the proportion of women diagnosed with GDM was reported with increasing S-25OHD concentrations, going from 17.8% in the group with S-25OHD concentrations < 30 nmol/L to 12.8% in the group with S-25OHD concentrations ≥75 nmol/L; however, the association was not significant (P for trend = 0.11). Conclusion: Approximately one-third of this cohort had S-25OHD concentrations below adequate levels (< 50 nmol/L) during the first trimester of pregnancy, which may suggest that necessary action must be taken to increase their vitamin D levels. No clear association was observed between the vitamin D status and GDM in this study. Keywords: cod liver oil; gestational diabetes mellitus; nutritional status; pregnancy; supplements; vitamin D.

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