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Biomedical subjects

A Prentice

Publications and source records attributed to A Prentice.

At least 73 records · Page 4Linked to original sources
PubMed1999

Randomised controlled trial of educational package on management of menorrhagia in primary care: the Anglia menorrhagia education study.

OBJECTIVE: To determine whether an educational package could influence the management of menorrhagia, increase the appropriateness of choice of non-hormonal treatment, and reduce referral rates from primary to secondary care. DESIGN: Randomised controlled trial. SETTING: General practices in East Anglia. SUBJECTS: 100 practices (348 doctors) in primary care were recruited and randomised to intervention (54) and control (46). INTERVENTIONS: An educational package based on principles of "academic detailing" with independent academics was given in small practice based interactive groups with a visual presentation, a printed evidence based summary, a graphic management flow chart, and a follow up meeting at 6 months. OUTCOME MEASURES: All practices recorded consultation details, treatments offered, and outcomes for women with regular heavy menstrual loss (menorrhagia) over 1 year. RESULTS: 1001 consultation data sheets for menorrhagia were returned. There were significantly fewer referrals (20% v 29%; odds ratio 0. 64; 95% confidence interval 0.41 to 0.99) and a significantly higher use of tranexamic acid (odds ratio 2.38; 1.61 to 3.49) in the intervention group but no overall difference in norethisterone treatment compared with controls. There were more referrals when tranexamic acid was given with norethisterone than when it was given alone. Those practices reporting fewer than 10 cases showed the highest increase in prescribing of tranexamic acid. CONCLUSIONS: The educational package positively influenced referral for menorrhagia and treatment with appropriate non-hormonal drugs.

Anti-Inflammatory Agents, Non-Steroidal↗
PubMed1999

Bone mineral changes during and after lactation.

OBJECTIVE: To assess bone mineral changes during and after lactation. METHODS: Fifty-nine breast-feeding women, 11 formula-feeding women, and 22 nonpregnant, nonlactating women had dual-energy x-ray absorptiometry measurements of the whole body, spine, hip, and forearm at 0.5 (baseline), 3, 6, and 12 months postpartum, with an additional measurement at 3 months after lactation for women who had breast-fed for more than 9 months. RESULTS: Lactation was associated with decreases in bone mineral at the whole body, spine, femoral neck, total hip, and radial wrist, which reversed as lactation declined and menstruation resumed. These changes were not seen in formula-feeding women. The magnitude and duration of the response were greater for women who breast-fed for a longer time. After lactation had stopped for at least 3 months, bone mineral, adjusted for bone area, had increased significantly above baseline at the whole body (+1.44%; 95% confidence interval [CI] +0.97%, +1.91%; P < .001), spine (+2.66%; 95% CI +1.60%, +3.72%; P < .001), and greater trochanter (+3.55%; 95% CI +2.53%, +4.57%; P < .001), was not different at the total hip and radial shaft, but was lower at the femoral neck (-2.07%; 95% CI -3.21%, -0.93%; P < .001) and radial wrist (-1.23%; 95% CI -1.99%, -0.47%; P < .01). Changes after lactation were largely independent of the duration of lactation or amenorrhea, and similar effects were observed in formula-feeding women. CONCLUSION: Lactation was associated with temporary decreases in bone mineral. After lactation, there were significant residual effects on bone mineral that were unrelated to the duration of lactation and may be related to having been pregnant. The long-term effect of lactation on the femoral neck requires further investigation.

Adult↗
PubMed1999

Epidemiological study of hip fracture in Shenyang, People's Republic of China.

The aim of this study was to investigate the incidence and epidemiology in 1994 of hip fracture in Shenyang, a large city in the northeast of The People's Republic of China, using register information and medical records collected from the 36 hospitals in Shenyang. The hip fracture data were restricted to cervical or trochanteric types. A subset (59% of total) of medical records of hip fracture was used to investigate the causes of hip fracture. The causes were classified as simple fall, fall from a bicycle during cycling, bicycle accident, car accident, and fall from a height. There was a total of 453 hip fractures (206 in women and 247 in men) in the population over 50 years of age. The age-adjusted 1 year cumulative incidence rate was 67/100,000 (95% confidence interval [CI] = 58-76/100,000) for women and 81/100,000 (95% CI = 71-91/100,000) for men. The standardized incidence rate against the 1985 U.S. population was 87/100,000 (95% CI = 77-97/100,000) for women and 100/100,000 (95% CI = 89-111/100,000) for men. The mean (+/-standard deviation) age of patients with a hip fracture was 67.5+/-9.8 years for men and 66.9+/-9.0 years for women. The overall male-to-female ratio of hip fracture was 1.21:1 for age-adjusted hip fracture incidence and 1.15:1 for standardized incidence. Simple fall accounted for 70% hip fractures in women but caused only 49% in men (chi2 = 11.2, degrees of freedom [df] = 1,p = 0.0008). The frequency of hip fractures caused by a fall from a bicycle was higher in men (28%) than women (10%) (chi2 = 13.0, df = 1,p = 0.0003). The results of this study indicate (1) a low incidence of hip fracture in a Chinese population compared with more affluent countries, and (b) a higher incidence in men than women that is related in part to a higher incidence of accidents, especially bicycle-related ones.

Accidental Falls↗
PubMed1999

Micronutrients: highlights and research challenges from the 1994-5 National Diet and Nutrition Survey of people aged 65 years and over.

The aims of the National Diet and Nutrition Survey series are summarized, and the new National Diet and Nutrition Survey of people aged 65 years and over is explored, with particular emphasis on micronutrient intakes and status indices. Mean nutrient intakes were generally satisfactory for most micronutrients, but intakes of vitamin D, Mg, K and Cu were low. Intakes of vitamin D were far below the reference nutrient intake for people aged 65 years and over, and there was also biochemical evidence of vitamin D deficiency, for 8% of free-living and 37% of institution participants, attributed partly to limited exposure to sunlight. A substantial proportion of people living in institutions had inadequate biochemical status indices, notably for vitamin C, Fe and folate. Relationships between intake and status were close for vitamins. Mineral intakes did not correlate well with currently used status indices. Some intakes and indices, especially those of vitamin C, carotenoids, Na and K, were strongly correlated with socio-economic status and with north-south gradients in Britain. Future research challenges should address the functional and health significance of low intakes and sub-optimal biochemical indices for certain micronutrients, especially for people living in institutions; the shortcomings of mineral status indices especially as indicators of mineral intake; the social and geographical inequalities of micronutrient intakes and status, and why micronutrient status deteriorates with increasing age. The answers to these questions will help to define the characteristics of nutritional risk for older people in Britain, and to clarify future needs for education and intervention.

Aged↗
PubMed1999

Use of medicines by older people in a large British national survey, and their relation to vitamin status indices.

OBJECTIVE: To describe the extent of use of medicines by older people living in Britain, and to explore relationships with vitamin status indices. DESIGN: The National Diet and Nutrition Survey of people aged 65 years and over collected data from a British sample during 1994-95. The present study has made novel use of it, to relate medicine use with biochemical indices of vitamin status. SETTING: Eighty postcode areas, selected randomly from mainland Britain. SUBJECTS: 1506 people, 65 years and over gave information about use of medication, and a 4-day weighed food record. Three-quarters gave blood for status indices. RESULTS: 78% of those living in the community and 93% of those in institutions were using medication. Certain vitamin status indices: plasma retinol, erythrocyte folate and riboflavin, paradoxically suggested better status in users than in non-users of antihypertensive, gastrointestinal, central nervous system, corticosteroid or diabetic drugs. There was evidence of a link with renal insufficiency, especially for plasma retinol, but neither this nor increased nutrient intake, acute phase effects or haemoconcentration could explain the paradoxical associations. CONCLUSIONS: Caution is needed in interpreting certain vitamin status indices, especially in older people who are extensively using medicines. New vitamin indices are needed, to avoid confounding interferences.

Aged↗
PubMed1999

Relationship between cigarette smoking and nutrient intakes and blood status indices of older people living in the UK: further analysis of data from the National Diet and Nutrition Survey of people aged 65 years and over, 1994/95.

OBJECTIVES: To examine the relationship between cigarette smoking and a range of nutrient intakes and blood status indices in older people. DESIGN: National Diet and Nutrition Survey: cross-sectional survey of nationally representative sample of people aged 65 years and over. SETTING: Mainland Britain during 1994/95. SUBJECTS: 1191 people (619 male, 572 female) aged 65 years and over, of whom 920 were living in private households and 271 were living in institutions. RESULTS: Cigarette smoking was inversely correlated with intakes of antioxidants and other micronutrients after adjustment for age, sex and domicile. Cigarette smoking was also inversely correlated with a number of antioxidant micronutrient status indices including plasma vitamin C and the carotenoids (but not vitamin E status indices), and with other micronutrient status indices, including plasma pyridoxal phosphate, red cell and serum folate, after adjustment for age, sex, domicile and the corresponding nutrient intake. Previous cigarette smoking or cigar/pipe smoking was not generally associated with lower nutrient intakes or status indices, however, both current and previous cigarette smoking was associated with increased concentrations of acute phase indicators. Further adjustment for total energy intake and/or sociodemographic, health and drug usage variables attenuated only a few of the associations observed. CONCLUSION: Older people who smoke cigarettes are at increased risk of suboptimal antioxidant and other micronutrient intakes and status, but the lower intakes found in cigarette smokers only partly explain their reduced blood indices.

Aged↗
PubMed1999

An appraisal of vitamin B6 status indices and associated confounders, in young people aged 4-18 years and in people aged 65 years and over, in two national British surveys.

OBJECTIVE: To compare vitamin B6 status indices with each other and with potential confounding factors, in the datasets from two national British surveys and associated studies. DESIGN: Vitamin B6 status was measured by plasma pyridoxal phosphate (PLP) and plasma pyridoxic acid (PA) in both surveys, and also by erythrocyte aspartate aminotransferase activation coefficient (EAATAC) in one of the surveys. Plasma alpha1-antichymotrypsin was measured as an index of acute phase status; plasma creatinine was measured as an index of renal function; and plasma total alkaline phosphatase activity was measured as a proxy for PLP hydrolase activity. SETTING: The survey of people aged 65 years and over was carried out in 80 postcode sectors across mainland Britain during 1994-95 and the survey of young people was carried out in 132 postcode sectors across mainland Britain during 1997. SUBJECTS: Blood samples from c. 1,000 subjects of both sexes in each survey permitted measurements of plasma PLP and PA. There were also measurements of EAATAC in the young people's survey. RESULTS: According to published limits of normality, only 5% or less of the young people had unacceptable vitamin B6 status as measured by plasma PLP. About half had apparently unacceptable status by EAATAC, but this observation is difficult to interpret. The young people had considerably higher plasma concentrations of PLP and lower concentrations of PA than the older people. In both surveys, plasma PLP was strongly correlated with plasma PA and in the young persons' survey it was also correlated, although much less strongly, with the basal activity and activation coefficient of aspartate aminotransferase. Both plasma PLP and EAATAC (but not PA nor basal aspartate aminotransferase activity) were influenced by acute phase status in young people, as indicated by significant correlations with alpha1-antichymotrypsin. In people aged 65 years and over, PA (but not PLP) was correlated with renal function, as indicated by its relation with plasma creatinine; however PLP (but not PA) was correlated with plasma alkaline phosphatase activity. CONCLUSIONS: Several potential confounders - acute phase reaction, kidney malfunction and hydrolase activity - may influence vitamin B6 status indices, although differently for different indices and different age groups. Since older people have relatively poor vitamin B6 status, which may have important health implications for them, more reliable vitamin B6 status indices are needed.

Adolescent↗
PubMed1999

North-south differences in some indices of Vitamin B6 nutritional status in older British people.

The National Diet and Nutrition Survey, nationally representative for the British population aged 65 years and over, has revealed a north-south geographical gradient, with a decline from south to north of vitamin B6 status indices. The present study further explores the possible explanatory factors (dietary intake of vitamin B6 and riboflavin, alcohol consumption, smoking habits and some other lifestyle determinants) on the difference of vitamin B6 indices--plasma concentrations of pyridoxal phosphate (pPLP) and pyridoxic acid (pPA), between older people living in the north (Scotland, North of England) and the south (Southern England, Wales and Midlands). The results showed that older people living in the northern half of Britain are at greater risk of poor vitamin B6 status, mainly as a result of low intakes of this vitamin, than the people living in the southern half of the country. Riboflavin intake, alcohol consumption, smoking and socio-economic status also correlated with the north-south gradient of pPLP and pPA. Other potential determinants such as use of vitamin B6 supplements, medicines probably affecting vitamin B6 metabolism, were not independent correlates of the north-south gradient in vitamin B6 status indices. This may have important implications for disease-risk geographical gradients in the UK.

Aged↗
PubMed1999

Vitamin D: seasonal and regional differences in preschool children in Great Britain.

OBJECTIVES: To examine seasonality of 25-hydroxyvitamin D (25OH-D) levels in British preschool children and the effect of vitamin D supplementation on this. DESIGN: The National Diet and Nutrition Survey of children aged 1.5 4.5 y in Britain during 1992-3 measured dietary intakes and blood status indices, including those for vitamin D, during all four seasons. The present study addresses the seasonal dependence of the relation between vitamin D intake and status. SETTING: 100 randomly selected postcode sectors throughout Britain, whose locations were classified as (a) Scotland; (b) Northern England; (c) Central, Wales, South+SW; (d) London+SE. SUBJECTS: Of 1859 whose parents or guardians were interviewed, 1675 provided a weighed diet estimate, and blood vitamin D status (25OH-D) was measured in 756, with approximately equal numbers in each season. RESULTS: Vitamin D status is highly dependent on season: moreover, the relation between vitamin D intake and status is also seasonally dependent, being strong in the winter and negligible in the summer. During the winter, those children who had relatively low 25OH-D concentrations generally were those not receiving vitamin D supplements. Vitamin D intakes and supplement use were lower in the north than in the south of Britain. CONCLUSIONS: For British preschool children, dietary vitamin D is of much greater importance in the winter than in the summer. There is evidence of regional inequality, with lesser use of supplements in the north. Supplements are needed in the winter, to achieve satisfactory vitamin D status and minimise the risk of rickets and of poor bone health, especially in high-risk groups.

Calcifediol↗
PubMed1999

Gender differences in food and nutrient intakes and status indices from the National Diet and Nutrition Survey of people aged 65 years and over.

OBJECTIVES: To determine the patterns and possible explanations for gender differences in food choices, nutrient intakes and status indices, especially for micronutrients, in a representative sample of older people living in Britain, who participated in the National Diet and Nutrition Survey of people aged 65 y and over during 1994-95. DESIGN: The Survey procedures included a health-and-lifestyle interview, a four-day weighed diet record, anthropometric measurements and a fasting blood sample for biochemical indices. SETTING: Eighty randomly-selected postcode sectors from mainland Britain. SUBJECTS: Of 1556 older people not living in institutions who were interviewed, 80% agreed to provide a complete four-day diet record and 63% agreed to give a blood sample for status index measurements. INTERVENTIONS: None. MAIN RESULT: The most highly significant gender differences in food choices were that women ate more butter, full-fat milk and certain beverages, cakes, apples, pears and bananas, whereas men ate more eggs, sugar, certain meat products and drank more alcoholic drinks, especially beer and lager. When adjusted for energy intakes, the younger women (65-79 y) had higher intakes than the younger men, of fat, retinol, vitamin C and calcium. The older women (80+ y) had higher intakes than older men, of fat and vitamin E, but lower intakes of protein, zinc and beta-carotene. The younger women had better status indices than the younger men: for alpha- and beta-carotenes, beta-cryptoxanthin and vitamin C. Women had higher plasma concentrations of cholesterol and HDL cholesterol, phosphate and copper, but lower indices of iron and vitamin D status, than men. These gender differences in status were not altered by inclusion of the corresponding nutrient intakes in the model. CONCLUSIONS: There are gender differences in food choices, in energy and nutrient intakes and in nutritional blood status indices in older British people, especially those aged 65-79 y. Some of the status differences are attenuated in the age group of 80 y and older, whereas others are enhanced. The relationships between the quantity and type of foods or nutrients consumed, and nutrient status, are complex. With respect to suspected risk and protective factors for vascular disease, women aged 65-79 y had significantly better status for plasma alpha- and beta-carotene, ascorbate, HDL-cholesterol and homocysteine; but, in contrast, they had lower blood haemoglobin concentrations and higher concentrations of total and non-HDL-cholesterol.

Age Factors↗
PubMed1999

Health care implications of dysfunctional uterine bleeding.

Objective menorrhagia (measured menstrual blood loss of > 80 ml) affects approximately 10% of the population, while the subjective complaint of menorrhagia is experienced by almost a third of the female population of childbearing age. Consequently, large numbers of women consult their general practitioners annually and many are subsequently referred on for gynaecological opinion. Ineffective utilization of medical therapies may result in inappropriate referral and subsequently may result in operative intervention. The introduction of many minimally invasive techniques to manage menorrhagia has not brought about the expected reduction in surgical intervention rates but has merely increased the overall operative burden on the National Health Service (NHS). Recent advances in medical therapy may, for the first time, offer a rational and effective alternative to surgical therapy but long-term clinical and cost effectiveness studies are required. At present menorrhagia continues to be a major drain on health care resources.

Adolescent↗
PubMed1999

Effective treatment of subfertility: introducing the Cochrane Menstrual Disorders and Subfertility Group.

The last two decades have seen a rapid explosion in research surrounding subfertility treatments. This ever-increasing volume of research has made it a difficult task for health professionals involved in the management of the subfertility to be able to assimilate the information easily. There is an urgent need for the findings from research to be synthesized into simple easy to read reviews that are both of a high quality and are based on the best evidence available. The Menstrual Disorders and Subfertility Group of the Cochrane Collaboration is attempting to address these issues by collecting a register of all the randomized controlled trials in the field of reproductive medicine and preparing systematic reviews on topics that will be of interest to healthcare workers and consumers. Readers are invited to participate in this process by identifying published and unpublished data and by helping in the process of preparing protocols and systematic reviews for inclusion in the Cochrane Library.

Female↗
PubMed1999

Lipid dynamics in the plasma membrane of fresh and cryopreserved human spermatozoa.

Preserving the integrity of the plasma membrane of spermatozoa is crucial for retention of their fertilizing capacity, especially after stressful procedures such as freezing and storage. In this investigation we have measured lipid diffusion in different regions of the plasma membrane of fresh and cryopreserved human spermatozoa using a sensitive, high resolution fluorescence photobleaching technique (FRAP) with 5-(N-octadecanyl)aminofluorescein as reporter probe. Results show that diffusion was significantly faster on the plasma membrane overlying the acrosome and decreased progressively in the postacrosome, midpiece and principal piece. The midpiece plasma contains a higher proportion of immobile lipids than other regions. In cryopreserved spermatozoa, lipid diffusion in the plasma membrane was significantly reduced on the acrosome, postacrosome and midpiece relative to fresh spermatozoa. Diffusion, however, could be restored to normal levels by washing spermatozoa in a medium containing 0.4% polyvinylpyrrolidine but not in medium alone or in medium containing 0.4% albumin. These results suggest that (i) lipid dynamics in the plasma membrane of human spermatozoa varies significantly between surface regions; (ii) in-plane diffusion is adversely affected by cryopreservation; and (iii) washing frozen spermatozoa in 0.4% polyvinylpyrrolidine restores membrane lipid fluidity to normal levels. The latter finding has important implications for improving the fertility of human spermatozoa following cryopreservation.

Adult↗
PubMed1999

Comparison of adult and paediatric spine and whole body software for the Lunar dual energy X-ray absorptiometer.

Simple phantoms were devised to compare the performance of adult (software 3.64) and paediatric (software 3.8 g) spine and whole body software developed for the Lunar dual energy X-ray absorptiometer. Rectangular slabs of aluminium with high (1.18 g cm-2) and low (0.57 g cm-2) density were used to represent bone mineral. For spine measurements, the phantoms were scanned in water at depths of 5-20 cm. For whole body measurements, the phantoms were scanned with known amounts of oil and water to represent fat and lean tissue. This simulated tissue depths of 5.5-19.7 cm and body composition ranging from 14-29% fat. There were systematic differences in spine and whole body bone mineral content (BMC), bone area (BA) and bone mineral density (BMD) measurements and also between adult and paediatric software versions. The magnitude and direction of these differences were dependent on BMD of the phantom and tissue depth. Similar systematic differences were observed in vivo when volunteers were scanned using adult and paediatric software. Paediatric software enabled measurements to be made at low tissue depths. The weights of fat, lean and total soft tissue measured by the adult and paediatric whole body software were similar to the values calculated from the known composition of the phantom. Precision estimates for all softwares were excellent. In conclusion, paediatric software should improve bone mineral measurements of children but the discrepancies between adult and paediatric softwares may cause problems in longitudinal studies of skeletal growth and when compiling reference data from infancy through to adulthood.

Absorptiometry, Photon↗
PubMed1999

Bone mineralization and turnover in preterm infants at 8-12 years of age: the effect of early diet.

Our previous studies raised two hypotheses: first that suboptimal early nutrition and second that human milk have enhancing effects on long-term bone mineralization. To test these hypotheses experimentally, we measured whole body and regional bone mineral content (BMC) and bone mineral density (BMD), using dual-energy X-ray absorptiometry and single-photon absorptiometry, and bone turnover at 8-12 years in 244 preterm children (128 boys) who participated in a prospective randomized study of diet during the neonatal period. Dietary randomizations studied were: banked human milk (BBM, n = 87) versus preterm formula (PTF, n = 96) as the sole diet or as a supplement to mother's expressed breast milk (EBM); PTF (n = 25) versus term formula (TF, n = 36) as sole diet. Ninety-five term children of the same age were also studied. First, preterm children were shorter and lighter than term children (height SD scores -0.49 (1.1) vs. +0.22 (0.9), weight SD scores -0.41 (1.2) vs. +0.38 (1.0)) and had significantly lower whole-body BMC than their peers; decrements were also evident at some regional sites. These differences disappeared after adjusting for bone area, body size, and pubertal status. Second, children previously randomized to BBM versus PTF or TF versus PTF showed no significant differences in anthropometry, BMC, BMD, or osteocalcin (OC). Third, there was no independent effect of the proportion of EBM on BMC, BMD, or OC and no interaction between randomized diet and the amount of EBM received. Fourth, plasma OC was significantly higher in preterm children than in term children (12.4 vs. 11.0 ng/ml, p < 0.005) and in preterm children who had received a low-nutrient (BBM/TF) as opposed to a high-nutrient diet (PTF) during the neonatal period (12. 9 vs. 11.9 ng/ml, p = 0.03). In conclusion, preterm children are shorter, lighter, and have lower bone mass than their peers at age 8-12 years. The lower BMC is, however, appropriate for the bone and body size achieved. Despite large differences in early mineral intake, early diet does not affect bone mass in preterm children, and fresh human milk has no specific effect. However, poor nutrition during the neonatal period may result in higher bone formation rates during childhood.

Biomarkers↗
PubMed1999

Plasma pyridoxal phosphate and pyridoxic acid and their relationship to plasma homocysteine in a representative sample of British men and women aged 65 years and over.

Concentrations of pyridoxal phosphate and pyridoxic acid were measured in fasting plasma samples from British men and women aged 65 years and over, participating in a National Diet and Nutrition Survey during 1994-5, selected to be representative of the population of mainland Britain. In this population, the concentration of pyridoxal phosphate declined, whereas pyridoxic acid rose, with increasing age and frailty; however, both status indicators were strongly and directly (with a positive coefficient) correlated with estimates of vitamin B6 intake. This was little affected by the inclusion of food energy and protein intakes in the model. Forty-eight percent of the participants living in the community and 75% of those living in institutions had plasma pyridoxal phosphate concentrations below a range considered normal from other studies. In a univariate regression model, plasma pyridoxal phosphate concentrations were inversely correlated with plasma homocysteine concentrations, consistent with the hypothesis that vitamin B6 status may influence plasma homocysteine levels, and hence vascular disease risk. However, this relationship was partly attenuated in a multiple regression model including age, sex, domicile and biochemical status indices, including those of folate and vitamin B12. There was evidence that plasma pyridoxal phosphate was sensitive to metabolic conditions associated with inflammation and the acute-phase reaction, and that plasma pyridoxic acid was sensitive to renal function. Thus, neither index is an ideal predictor of vitamin B6 status in older people, unless these confounding factors are allowed for. Since poor vitamin B6 status may have health implications, e.g. for immune function, cognition, and for essential intermediary metabolic pathways in older people, it needs to be investigated as a possible public health problem.

Adolescent↗