Biomedical subjects

Linda Dodds

Publications and source records attributed to Linda Dodds.

23 records · Page 2Linked to original sources

PubMed2003

A population-based study of prognostic factors related to major disability in very preterm survivors.

OBJECTIVE: This study was conducted to determine the rates and risk factors for major disability in very preterm survivors born to residents of Nova Scotia, Canada between 1992 and 1996. STUDY DESIGN: A cohort study was conducted of all 355 infants born to Nova Scotia residents between 22 and 30 weeks gestation. Major disability was defined by mental development index <70, moderate or severe cerebral palsy, bilateral visual acuity <20/200, or deafness requiring bilateral hearing aids. Logistic regression analysis was used to determine which factors were significantly associated with major disability. RESULTS: Of the infants who survived 1 year and had follow-up data, 21 (8.3%) developed a major disability. Cystic periventricular leukomalacia (PVL), hypernatremia and surgery requiring general anesthesia were independently associated with the development of a major disability. CONCLUSION: This study confirms the association between cystic PVL and major disability observed in other studies. Surgery and hypernatremia will be important to verify in future studies since preventive measures may be possible.

Confidence Intervals↗

PubMed2003

Unexplained elevated maternal serum alpha-fetoprotein and/or human chorionic gonadotropin and the risk of adverse outcomes.

OBJECTIVE: The study was undertaken to determine the risks of adverse obstetric outcomes in pregnant women with unexplained elevations of maternal serum alpha-fetoprotein (MSAFP) and/or human chorionic gonadotropin (hCG) and to determine whether these risks vary by prepregnancy risk status. STUDY DESIGN: All women who underwent double-marker screening (MSAFP+hCG) between 1994 and 2000 and were delivered of an infant in Nova Scotia, Canada, during this period were identified from a hospital serum screening database and a provincial perinatal database. Patients with inaccurate dating, major structural anomalies, or chromosomal abnormalities were excluded. The primary outcomes studied were preeclampsia, abruptio placentae, fetal growth restriction, fetal death, and preterm birth. Women with medical or previous obstetric complications were designated high risk. Logistic regression, controlling for confounding factors, was used to estimate the relative risks (RRs) and 95% CI for elevated levels of MSAFP and/or hCG and each of the outcomes. RESULTS: Among the 14,374 women who met the study criteria, 5,789 were designated high risk. Except for abruptio placentae, unexplained elevated MSAFP or elevated hCG levels were independently associated with all the outcomes in both high- and low-risk women. Elevated screening values were associated with increased risk of abruptio placentae among low-risk women only. Particularly large RRs were seen for fetal death in both high- and low-risk women (RR=4.9, 95% CI 2.7-8.7 for elevated MSAFP or hCG in high- and low-risk women combined). CONCLUSION: Unexplained elevated levels of MSAFP and/or hCG are associated with an increased risk of most pregnancy complications. Increased antenatal surveillance of these patients is important regardless of prepregnancy risk status.

Abruptio Placentae↗

PubMed2002

Does chorionicity or zygosity predict adverse perinatal outcomes in twins?

OBJECTIVE: The purpose of this study was to evaluate chorionicity and zygosity as risk factors for adverse perinatal outcomes in twins. STUDY DESIGN: A population-based, retrospective cohort study was conducted of all twin deliveries in Nova Scotia, Canada, from 1988 to 1997. Chorionicity was established by histologic examination. Zygosity was determined by chorionicity, sex, and infant blood group. Three groups were established: monochorionic/monozygotic twins, dichorionic/dizygotic twins, and dichorionic/majority monozygotic twins. RESULTS: Outcomes from 1008 twin pregnancies were analyzed. Monochorionic/monozygotic twins had lower mean birth weights compared with dichorionic/dizygotic twins. Rates of perinatal mortality of at least 1 twin were significantly higher among monochorionic/monozygotic twins relative to dichorionic/dizygotic twins (relative risk, 2.5; 95% CI, 1.1-2.5). Dichorionic/majority monozygotic twins had similar perinatal outcomes compared with dichorionic/dizygotic twins. CONCLUSION: Monochorionicity increases the risk of adverse perinatal outcome, whereas the effect of zygosity is less clear. Because chorionicity can be determined by prenatal ultrasound scanning, this information should be considered in the prenatal care of twin pregnancies.

Adult↗

PubMed2002

Assessing exposure in epidemiologic studies to disinfection by-products in drinking water: report from an international workshop.

The inability to accurately assess exposure has been one of the major shortcomings of epidemiologic studies of disinfection by-products (DBPs) in drinking water. A number of contributing factors include a) limited information on the identity, occurrence, toxicity, and pharmacokinetics of the many DBPs that can be formed from chlorine, chloramine, ozone, and chlorine dioxide disinfection; b) the complex chemical interrelationships between DBPs and other parameters within a municipal water distribution system; and c) difficulties obtaining accurate and reliable information on personal activity and water consumption patterns. In May 2000, an international workshop was held to bring together various disciplines to develop better approaches for measuring DBP exposure for epidemiologic studies. The workshop reached consensus about the clear need to involve relevant disciplines (e.g., chemists, engineers, toxicologists, biostatisticians and epidemiologists) as partners in developing epidemiologic studies of DBPs in drinking water. The workshop concluded that greater collaboration of epidemiologists with water utilities and regulators should be encouraged in order to make regulatory monitoring data more useful for epidemiologic studies. Similarly, exposure classification categories in epidemiologic studies should be chosen to make results useful for regulatory or policy decision making.

Acetates↗

PubMedDate not supplied

Changes in maternal characteristics in Nova Scotia, Canada from 1988 to 2001.

BACKGROUND: Maternal characteristics such as age, parity, smoking status, pre-pregnancy weight and pregnancy weight gain have changed in many industrialized countries in recent years. Many of these changes have not been adequately described at a population level. The purpose of this study was to describe recent trends in selected maternal characteristics in Nova Scotia. METHODS: Data from a population-based perinatal database were used to examine changes in maternal age, parity, smoking, pre-pregnancy weight, delivery weight and pregnancy weight gain among all deliveries between 1988 and 2001. RESULTS: The proportion of deliveries to women > or = 35 years increased by 84% over the study period from 7.0% in 1988-1991 to 12.9% in 1998-2000, while deliveries to women > or = 40 years increased by more than 100%. The number of nulliparous women > or = 35 years also increased significantly. The overall prevalence of smoking decreased from 32.7% in 1988-1991 to 25.1% in 1998-2001, however the prevalence of smoking among women <20 years did not change over the study period and was almost 50%. The proportion of women with a pre-pregnancy weight of > or = 90 kilograms (kg) increased by 165% from 4.1% in 1988-1991 to 10.7% in 1998-2001. The proportion of women with pregnancy weight gain of < 7 kg and > or =18 kg increased by 37% and 13%, respectively. CONCLUSION: Dramatic changes have occurred in several important maternal characteristics and there is evidence of ongoing change. Continuation of these trends is likely to impact on future obstetric practice and perinatal health.

Adult↗