Biomedical subjects

Simon A Ogston

Publications and source records attributed to Simon A Ogston.

10 recordsLinked to original sources

PubMed2006

Mortality in people diagnosed with type 2 diabetes at an older age: a systematic review.

OBJECTIVES: To review all published observational studies reporting on all-cause mortality in patients with type 2 diabetes to determine the degree of increased mortality when diagnosed at an older age. DESIGN: Systematic literature search. SETTING: The review included studies carried out in populations from Germany, United Kingdom, United States, Japan, Italy, Western Australia, Netherlands and Sweden. MEASUREMENTS: Medline, CINAHL, EMBASE, National Research Register and Cochrane Reviews were systematically searched from 1975 to 2004. We identified observational studies that reported overall mortality for people diagnosed with type 2 diabetes when they were over the age of 60, compared with a non-diabetic population. Outcome measures were expressed as risk ratios or relative risks. RESULTS: Among 14 eligible studies, one study reported reduced mortality for patients diagnosed with type 2 diabetes over the age of 60, whereas another found virtually no increased risk of mortality. However, 7 of the 14 studies reported increased mortality in all patients diagnosed when older, and 5 studies for certain subgroups only. A meta-analysis showed the combined relative risks (with 95% CI) of increased mortality for men diagnosed between the ages of 60 and 70 to be 1.38 (1.08-1.76) and 1.13 (0.88-1.45) for men diagnosed aged 70 years or older. A similar pattern was found for the same age groups for women, with combined relative risks of 1.40 (1.10-1.79) and 1.19 (0.93-1.52) respectively. CONCLUSION: Increased mortality associated with a diagnosis of type 2 diabetes at an older age is lower than that reported for the general older diabetic population.

Age Factors↗

PubMed2006

Vitamin A and lung function in CF.

Laboratory evidence suggests that vitamin A could have a protective effect on respiratory status in patients with cystic fibrosis (CF). This study shows a significant correlation between serum vitamin A concentrations and every aspect of lung function tested in 38 patients with stable CF. Serum vitamin D and vitamin E concentrations were also measured but did not show any significant correlations with lung function.

Adolescent↗

PubMed2005

Serum thyroid hormones in preterm infants: associations with postnatal illnesses and drug usage.

CONTEXT: Transient hypothyroxinemia is common in infants less than 30 wk gestation and is associated with neurodevelopmental deficits. Reductions in T4 and T3 levels with TSH unchanged are the key features of severe illness using surrogate indices of overall severity of illness, but these do not inform the impact of individual disease conditions or drug use. OBJECTIVE: Our objective was to investigate the contribution of postnatal factors to the variations in serum levels of iodothyronines, thyroid-binding globulin, and TSH. DESIGN: We recruited a cohort of infants (23-34 wk gestation; n = 780) between January 1998 and September 2001. SETTING AND PATIENTS: The study involved 11 level III Scottish neonatal intensive care units and included cohorts of infants delivered at 23-34 wk gestation. MAIN OUTCOME: We assessed serum levels of iodothyronines, thyroid-binding globulin, and TSH at 7, 14, and 28 d adjusted for the potentially significant postnatal influences (n = 31). RESULTS: Serum levels of TSH, free T4, T3, and T4 are variably but significantly associated with bacteremia, endotracheal bacterial cultures, persistent ductus arteriosus, necrotizing enterocolitis, cerebral ultrasonography changes, oxygen dependence at 28 d, and the use of aminophylline, caffeine, dexamethasone, diamorphine, and dopamine. CONCLUSIONS: There are many more associations of postnatal factors with transient hypothyroxinemia than had previously been considered in preterm infants. Alternative strategies should be considered for correction of hypothyroxinemia rather than sole reliance on the direct therapy of hormone replacement. A more oblique preventative approach may be necessary through reduction in the incidence or severity of individual illness(es). Similarly, alternatives to those drugs that interfere with the hypothalamic-pituitary-thyroid axis should be evaluated (e.g. other inotropics instead of dopamine).

Aminophylline↗

PubMed2005

Transient hypothyroxinemia in preterm infants: the role of cord sera thyroid hormone levels adjusted for prenatal and intrapartum factors.

CONTEXT: Transient hypothyroxinemia is common in infants less than 30 wk gestation and is associated with neurodevelopmental deficits; it has no consensus definition. We previously suggested that appropriate ranges for postnatal serum T4 values are at least cord levels corrected to an equivalent gestational age if the fetuses had remained in utero. OBJECTIVE: The study objective is to investigate the contribution of prenatal and intrapartum factors (n = 27) to the variations in cord levels of iodothyronines, T4-binding globulin, and TSH, and to provide an appropriate definition of transient hypothyroxinemia. DESIGN: The study design is a cohort study (n = 620) in 11 Scottish neonatal intensive care units. PATIENTS: Infants were delivered at 23- to 42-wk gestation and recruited between January 1998 and September 2001. RESULTS: Using -2 SD of adjusted T4 cord levels applied to postnatal d-7 values of equivalent gestational age, 14% of the 23- to 27-wk group, 1% of the 28- to 30-wk group, and 3% of the 31- to 34-wk group are hypothyroxinemic; using -1 SD, the respective figures are 41, 23, and 12%. CONCLUSIONS: In the absence of neurodevelopmental follow-up studies to quantify transient hypothyroxinemia, a pragmatic criterion is necessary for selection of extreme preterm infants into clinical trials of T4 supplementation. We suggest the use of serum T4 levels on postnatal d 7 that are below -1 SD of adjusted cord T4 levels of equivalent gestational age. This criterion avoids over-recruitment of the more mature infants in whom universal T4 supplementation is detrimental to neurodevelopmental outcome, but still allows selection of the least mature entrants on whom universal T4 supplementation is beneficial.

Chemistry, Clinical↗

PubMed2005

Asians with cystic fibrosis in the UK have worse disease outcomes than clinic matched white homozygous delta F508 controls.

BACKGROUND: We tested the hypothesis that the Asian cystic fibrosis (CF) phenotype is comparable to the commonest genetic form of CF found in 50% of the white UK CF population using the UK CF Database, a national disease-specific patient registry. METHODS: 50 Asian CF patients were matched by Centre with 143 white homozygous delta F508 patients for gender, age and chronic Pseudomonas aeruginosa status (a marker of morbidity). The authors compared FEV1 and FVC% predicted, mean height, weight and BMI Z scores. RESULTS: FVC% predicted, weight and BMI Z scores were significantly worse in the Asians. Asian male/female FVC% predicted (p-value, 95% CI) -15.1 (p=0.001, -24.0, -8.8)/-15.2 (p=0.014, -27.1, -3.3) compared with white controls. Asian females also had significantly worse FEV1% predicted compared with controls (-14.9, p=0.025, 95% CI: -27.8, -2.0). Asians had significantly lower raw Z scores for weight (males p=0.002, females p=0.013) and BMI (males p=0.002, females p=0.008). CONCLUSIONS: These data suggest that the Asian CF phenotype is as severe as the white controls with the homozygous delta F508 phenotype but is worse in some outcomes, especially in Asian females. Socio-cultural factors and rare CF genotypes may contribute to the severity of CF in this vulnerable group.

Adolescent↗

PubMed2005

Overweight and obesity in deltaF508 homozygous cystic fibrosis.

Overweight (9%) and obesity (1%) in patients with cystic fibrosis homozygous for the deltaF508 mutation (CFdeltaF508) were non-trivial. Children with CFdeltaF508, in contrast to the general population, showed a positive association between body mass index and lung function for all body mass index z-scores.

Adolescent↗

PubMed2004

Serum thyroid hormones in preterm infants and relationships to indices of severity of intercurrent illness.

The purpose of this study was to relate severity of illness at 1, 7, 14, and 28 postnatal days in preterm infants groups, 23-27 (n = 73), 28-30 (n = 160), and 31-34 (n = 208) wk gestation, to the corresponding sera levels of T(4), free T(4), T(4)-binding globulin, TSH, T(3), rT(3), and T(4) sulfate. The British Association of Perinatal Medicine and Neonatal Nurses Association 1992 scoring categories (published elsewhere) were used as an index of illness severity: level 1 (maximal intensive care) was compared with level 2 (high-dependency intensive care) combined with level 3 (special care); infants were scored on 1, 7, 14, and 28 postnatal days. In level 1 infants, there were significant reductions in T(3) at 7 d (28-30 wk), 14, and 28 d (23-27 and 28-30 wk); T(4) at 7, 14, and 28 d (23-27 wk); at 14 and 28 d (28-30 wk); and at 7 d (31-34 wk); and free T(4) at 14 d (23-27 wk). TSH was unchanged in all groups at all ages and with reductions in T(4) and T(3) being the key features of severe illness in extreme preterm infants.

Age Factors↗

PubMed2004

The hypothalamic-pituitary-thyroid axis in preterm infants; changes in the first 24 hours of postnatal life.

The purpose of this study was to measure serum T4, free T4, TSH, T3, rT3, T4 sulfate, and thyroxine binding globulin at four time points within the first 24 h of life (cord and 1, 7, and 24 h) in infants between 24 and 34 wk gestation. The infants were subdivided into gestational age groups: 24-27 wk (n = 22); 28-30 wk (n = 26); and 31-34 wk (n = 24). The TSH surge in the first hour of postnatal life was markedly attenuated in infants of 24-27 wk gestation [8 compared with 20 (28-30 wk) and 23 mU/liter (31-34 wk)]. T4 levels in the most immature group declined over the first 24 h, whereas levels increased in the more mature groups [mean cord and 24-h levels: 65 and 59 (NS) vs. 70 and 84 (P < 0.002) vs. 98 and 125 (NS) nmol/liter]. Free T4 and T3 showed only small, transient increases in the most immature group and progressively larger and sustained increases in the other gestational groups. rT3 and T4 sulfate levels in cord serum were higher in the most immature infants, and in all groups levels decreased initially and then variably increased. The features of a severely attenuated or failed hypothalamic-pituitary-thyroid response to delivery critically define this 24- to 27-wk group as distinct from more mature preterm infants.

Humans↗

PubMed2004

Developmental trends in cord and postpartum serum thyroid hormones in preterm infants.

The purpose of this study was first to clarify postnatal trends in sera T(4), free T(4) (FT(4)), T(4)-binding globulin, TSH, T(3), rT(3), and T(4) sulfate levels in cord and at 7, 14, and 28 d in groups of preterm infants at 23-27 wk (n = 101), 28-30 wk (n = 196), and 31-34 (n = 253) wk gestation, and second to compare these trends to those of term infants and also with cord sera levels of equivalent gestational ages (n = 812; 23-42 wk gestation). In all preterm groups, TSH and rT(3) decrease to below, T(4)-binding globulin increases to within, and T(3) and T(4) sulfate increase to above cord levels of equivalent gestational age. Term infants are hyperthyroxinemic relative to cord and nonpregnant adult levels of T(4). Postnatal T(4) increases are attenuated in 31- to 34-wk infants, absent in 28- to 30-wk infants (although levels are equivalent to gestational age), and crucially reversed in 23- to 27-wk infants. This immature group is hypothyroxinemic relative to other groups and to cord levels of equivalent gestational age. Compared with term infants, postnatal FT(4) increases are lower in 31- to 34-wk infants, attenuated in 28- to 30-wk infants, and absent in 23- to 27-wk infants. The 23- to 27-wk group is distinctive; they are hypothyroxinemic on T(4) levels, yet FT(4) levels are within the cord levels of equivalent gestational age.

Fetal Blood↗

PubMed2002

Does renal dysfunction predict mortality after acute stroke? A 7-year follow-up study.

BACKGROUND AND PURPOSE: The purpose of this study was to investigate renal function as a long-term predictor of mortality in patients hospitalized for acute stroke. METHODS: This was a cohort study done in a Scottish tertiary teaching hospital. Participants included 2042 (993 male) unselected consecutive stroke patients (mean age, 73 years) admitted to hospital within 48 hours of stroke between 1988 and 1994. Follow-up was up to 7 years. Main outcome measure was all-cause mortality. RESULTS: The total number of deaths at the end of follow-up was 1026. Most subjects (1512) had creatinine <124 micromol/L. The mean calculated creatinine clearance was 54.8 mL/min (SD, 23 mL/min). Renal function indexes were analyzed by quartiles with Cox proportional-hazards model. Stroke survivors had higher calculated creatinine clearance and lower serum creatinine, urea, and ratios of urea to creatinine. Calculated creatinine clearance > or =51.27 mL/min significantly predicted better long-term survival in these stroke patients even after adjustment for confounders (age, neurological score, ischemic heart disease, hypertension, smoking, and diuretic use). Similarly, creatinine > or =119 micromol/L "relative risk (RR), 1.59; 95% confidence interval (CI), 1.32 to 1.92", urea 6.8 to 8.9 mmol/L (RR, 1.34; 95% CI, 1.09 to 1.65) or > or =9 mmol/L (RR, 1.74; 95% CI, 1.42 to 2.13), and ratio of urea to creatinine > or =0.08573 mmol/micromol (RR, 1.24; 95% CI, 1.03 to 1.50) remained significant predictors of mortality after adjustment for confounders. CONCLUSIONS: After acute stroke, patients with reduced admission calculated creatinine clearance, raised serum creatinine and urea concentrations (even within conventional reference intervals), and raised ratio of urea to creatinine had a higher mortality risk. This finding may be used to stratify risk and target interventions, eg, the use of angiotensin-converting enzyme inhibitors.

Aged↗