Biomedical subjects

Derek G Cook

Publications and source records attributed to Derek G Cook.

29 records · Page 2Linked to original sources

PubMed2004

Cellular adhesion molecules and blood pressure: interaction with sex in a multi-ethnic population.

OBJECTIVE: To clarify the association between blood pressure and four different adhesion molecules, adjusting for potential confounders, in men and women from different ethnic origins. DESIGN AND METHODS: The soluble (s) plasma adhesion molecules sP-selectin, sE-selectin, intracellular adhesion molecule-1 (sICAM-1) and vascular cell adhesion molecule-1 (sVCAM-1) were measured in 261 white (120 women), 188 African origin (99 women) and 215 South Asian (99 women) individuals living in England. All were free from coronary heart disease, stroke, other cardiovascular disease and diabetes, and were not receiving drug treatment for hypertension or high lipids, hormone replacement therapy or oral contraceptives. RESULTS: After adjustment for age, only sE-selectin concentrations were significantly associated with blood pressure. There was a significant interaction of sex with systolic (P = 0.013), diastolic (P = 0.042) and pulse (P = 0.015) pressures. After adjustment for age, ethnicity, body mass index and smoking, the significant interaction of sex persisted and in women the associations with systolic (P < 0.001), diastolic (P < 0.001) or pulse (P = 0.004) pressure were unchanged, but in men the association with diastolic blood pressure was abolished. Finally, the association appeared to be present in women younger than 50 years, who were likely to be premenopausal. CONCLUSIONS: The relationship between adhesion molecules and blood pressure is adhesion molecule specific and varies with sex and age, which may partially explain previous inconsistencies in the literature. The mechanisms relating blood pressure to adhesion molecule concentrations are unknown, but they are likely to be modified by the menopause. These differences may relate to the production, clearance or cell-surface shedding of the adhesion molecules.

Asian People↗

PubMed2004

Linking survey data with computerised records to predict consulting by older people.

Despite high consultation rates, little is known about predictors of primary care use by older people. A survey of patients aged > or = 65 years from two London practices included details on physical health and functioning, psychological measures, social support, and socioeconomic measures. The response rate was 75% (1704/2276). We obtained consent to link the survey data to subjects' computerised primary care records for 92% (1565/1704) of responders. Individual factors (physical ill health, anxiety, female sex), social factors (frequent telephone contact with friends or family), and practice factors independently predicted consultation in the year post survey. Although physical ill health was the most important, the other factors had independent effects and may be useful in understanding the increase in consulting by older people.

Aged↗

PubMed2003

Effect of breast feeding in infancy on blood pressure in later life: systematic review and meta-analysis.

OBJECTIVE: To determine whether breast feeding in infancy compared with bottle feeding formula milk is associated with lower mean blood pressure at different ages. DESIGN: Systematic review. DATA SOURCES: Embase, Medline, and Web of Science databases. STUDY SELECTION: Studies showing the effects of feeding in infancy on blood pressure at different ages. DATA EXTRACTION: Pooled mean differences in blood pressure between breast fed infants and those bottle fed formula milk, based on random effects models. DATA SYNTHESIS: The pooled mean difference in systolic blood pressure was -1.10 mm Hg (95% confidence interval -1.79 to -0.42 mm Hg) but with significant heterogeneity between estimates (P < 0.001). The difference was largest in studies of < 300 participants (-2.05 mm Hg, -3.30 to -0.80 mm Hg), intermediate in studies of 300-1000 participants (1.13 mm Hg, -2.53 to 0.27 mm Hg), and smallest in studies of > 1000 participants (-0.16 mm Hg, -0.60 to 0.28 mm Hg). An Egger test but not Begg test was statistically significant for publication bias. The difference was unaltered by adjustment for current size and was independent of age at measurement of blood pressure and year of birth. Diastolic blood pressure was not significantly related to type of feeding in infancy. CONCLUSIONS: Selective publication of small studies with positive findings may have exaggerated claims that breast feeding in infancy reduces systolic blood pressure in later life. The results of larger studies suggest that feeding in infancy has at most a modest effect on blood pressure, which is of limited clinical or public health importance.

Adolescent↗

PubMed2003

Implications of the problem orientated medical record (POMR) for research using electronic GP databases: a comparison of the Doctors Independent Network Database (DIN) and the General Practice Research Database (GPRD).

BACKGROUND: The General Practice Research Database (GPRD) and Doctor's Independent Network Database (DIN), are large electronic primary care databases compiled in the UK during the 1990s. They provide a valuable resource for epidemiological and health services research. GPRD (based on VAMP) presents notes as a series of discrete episodes, whereas DIN is based on a system (MEDITEL) that used a Problem Orientated Medical Record (POMR) which links prescriptions to diagnostic problems. We have examined the implications for research of these different underlying philosophies. METHODS: Records of 40,183 children from 141 practices in DIN and 76,310 from 464 practices in GRPD who were followed to age 5 were used to compare the volume of recording of prescribing and diagnostic codes in the two databases. To assess the importance and additional value of the POMR within DIN, the appropriateness of diagnostic linking to skin emollient prescriptions was investigated. RESULTS: Variation between practices for both the number of days on which prescriptions were issued and diagnoses were recorded was marked in both databases. Mean number of "prescription days" during the first 5 years of life was similar in DIN (19.5) and in GPRD (19.8), but the average number of "diagnostic days" was lower in DIN (15.8) than in GPRD (22.9). Adjustment for linkage increased the average "diagnostic days" to 23.1 in DIN. 32.7% of emollient prescriptions in GPRD appeared with an eczema diagnosis on the same day compared to only 19.4% in DIN; however, 86.4% of prescriptions in DIN were linked to an earlier eczema diagnosis. More specifically 83% of emollient prescriptions appeared under a problem heading of eczema in the 121 practices that were using problem headings satisfactorily. CONCLUSION: Prescribing records in DIN and GPRD are very similar, but the usage of diagnostic codes is more parsimonious in DIN because of its POMR structure. Period prevalence rates will be underestimated in DIN unless this structure is taken into account. The advantage of the POMR is that in 121 of 141 practices using problem headings as intended, most prescriptions can be linked to a problem heading providing a specific reason for their issue.

Child, Preschool↗

PubMed2003

Ethnic differences in circulating soluble adhesion molecules: the Wandsworth Heart and Stroke Study.

The aim of this study was to investigate whether soluble adhesion molecule levels differ by ethnic group. Soluble plasma adhesion molecules [soluble P-selectin (sP-selectin), soluble E-selectin (sE-selectin), soluble intercellular adhesion molecule-1 (sICAM-1) and soluble vascular cell adhesion molecule-1 (sVCAM-1)] were measured in 261 white (120 females), 188 African origin (99 females) and 215 South Asian (99 females) individuals living in England. All were free from coronary heart disease, stroke and other cardiovascular disease, diabetes, drug therapy for hypertension or high lipids, hormone-replacement therapy or oral contraceptive pill. The results of the study indicated that there were important differences in the levels of adhesion molecules by sex and smoking. However, when adjusting for these and other potential confounders, there were no differences in levels between white subjects and individuals of South Asian origin. In contrast, people of African origin had significantly lower levels of sICAM-1 [Caribbean -30% (-36 to -23%); West African -22% (-29 to -15%), values are means (95% confidence intervals)], sVCAM-1 [Caribbean -14% (-19 to -8%); West African -10% (-17 to -3%)] and sP-selectin [Caribbean -10% (-17 to -2%); West African -24% (-31 to -16%)] than white individuals. In conclusion, circulating levels of some soluble adhesion molecules are lower in individuals of Caribbean or West African origin compared with white or South Asian individuals. These relationships may contribute to the low risk of coronary heart disease seen in people of African origin living in England.

Adult↗

PubMed2003

Predictors of depressive symptoms in older people--a survey of two general practice populations.

BACKGROUND: Studies have shown strong associations between disability, social support and depressive symptoms in older people; but socio-economic effects are less clear and little is known about the role of health locus of control. OBJECTIVE: To examine the roles of physical health, disability, social support, socio-economic factors and health locus of control as predictors of depressive symptoms in older people. METHOD: A postal survey of patients aged >/= 65 years from two London practices. Outcome measure was a score of > 5 on the 15-item Geriatric Depression Scale. Associations with other factors were examined using logistic regression and expressed as odds ratios. RESULTS: 70.4% (1602/2276) responded and provided Geriatric Depression Score 15 data, with 23.8% (381/1602) scoring > 5. After adjusting for age, sex and practice, high depression scores were associated with: (i) physical health and disability [e.g. severe versus no disability odds ratio 26.9 (15.7-46.2)]; (ii) social support [e.g. dissatisfaction with support odds ratio 4.2 (3.2-5.6)]; (iii) socio-economic [e.g. no occupational pension odds ratio 1.9 (1.5-2.4)]; (iv) health locus of control [e.g. internality 0.6 (0.6-0.7)]. After adjusting for disability, associations with general measures of physical health were reduced but still significant, while associations with social support, socio-economic factors, and health locus of control were unaffected. All four groups of factors were included in a final model for predicting depressive symptoms. CONCLUSIONS: Disability, physical health, social support, socio-economic factors, and health locus of control were all independent depression score predictors in this study. This has implications for measures to reduce depressive symptoms in older people.

Aged↗

PubMed2003

Birth weight and blood cholesterol level: a study in adolescents and systematic review.

OBJECTIVE: To examine the relationship between birth weight and blood total cholesterol (TC) and to compare its strength with that of the relationship between current body mass index and TC. METHODS: 1). Cross-sectional study of adolescents, with retrospective ascertainment of birth weight from birth records or parental recall; 2). systematic review of studies examining the relations between birth weight and cholesterol at all ages. PARTICIPANTS: 1). 1532 individuals (92% white, 55% male) in 10 British towns; 2). 28 studies with 32 observations showing the change in TC per 1 kg increase in birth weight-6 in infancy, 14 in adolescents, 12 in adults. RESULTS: In the cross-sectional study, there was a weak inverse relation between birth weight and TC level (-.061 mmol/L fall in TC per kg increase in birth weight, 95% confidence interval -.131 to.008 mmol/L per kg) which was little affected by adjustment for current body size. The difference in TC corresponding to an interquartile range increase in birth weight (-.03 mmol/L) was approximately a quarter of that for an equivalent increase in body mass index (.11 mmol/L). In the systematic review, an inverse association between birth weight and TC of a similar size to that in the cross-sectional study was observed (-.048 mmol/L per kg, 95% confidence interval -.078 to -.018 mmol/L per kg) similar in strength at all ages. CONCLUSION: The relation of fetal nutrition to TC appears to be weak and is probably of limited public health importance when compared with the effects of childhood obesity.

Adolescent↗

PubMed2002

Early evidence of ethnic differences in cardiovascular risk: cross sectional comparison of British South Asian and white children.

OBJECTIVES: To examine whether British South Asian children differ in insulin resistance, adiposity, and cardiovascular risk profile from white children. DESIGN: Cross sectional study. SETTING: Primary schools in 10 British towns. PARTICIPANTS: British children aged 8 to 11 years (227 South Asian and 3415 white); 73 South Asian and 1287 white children aged 10 and 11 years provided blood samples (half fasting, half after glucose load). MAIN OUTCOME MEASURES: Insulin concentrations, anthropometric measures, established cardiovascular risk factors. RESULTS: Mean ponderal index was lower in South Asian children than in white children (mean difference -0.43 kg/m(3), 95% confidence interval -0.13 kg/m(3) to -0.73 kg/m(3)). Mean waist circumferences and waist:hip ratios were similar. Mean insulin concentrations were higher in South Asian children (percentage difference was 53%, 14% to 106%, after fasting and 54%, 19% to 99%, after glucose load), though glucose concentrations were similar. Mean heart rate and triglyceride and fibrinogen concentrations were higher among South Asian children; serum total, low density lipoprotein, and high density lipoprotein cholesterol concentrations were similar in the two groups. Differences in insulin concentrations remained after adjustment for adiposity and other potential confounders. However, the relations between adiposity and insulin concentrations (particularly fasting insulin) were much stronger among South Asian children than among white children. CONCLUSIONS: The tendency to insulin resistance observed in British South Asian adults is apparent in children, in whom it may reflect an increased sensitivity to adiposity. Action to prevent non-insulin dependent diabetes in South Asian adults may need to begin during childhood.

Adipose Tissue↗

PubMed2002

Homocysteine levels in men and women of different ethnic and cultural background living in England.

This population-based cross-sectional study in South London looks at the total homocysteine (tHcy) levels in groups of different ethnic background and the possible role of environmental factors and the 677C-->T genetic polymorphism of the methylenetetrahydrofolate reductase (MTHFR). Fasting plasma tHcy was measured in 1392 men and women, age 40-59 years; 475 were white, 465 of African origin (of whom 180 were West Africans and 280 Caribbeans) and 452 South Asian (of whom 222 were Hindus and 167 Muslims). The homozygous MTHFR TT variant had observed frequencies of 0.10 in whites, 0.01 in people of African origin and 0.02 in South Asians (P<0.001). tHcy levels were 16% (95% CI 8-26) higher amongst TT than CC. tHcy levels were 25% (21-29) higher in men than women. Levels were significantly higher in South Asians than whites (8% [3-13]). Vegetarians had higher levels than non-vegetarians (25% [18-33]). These differences were present after adjustments for age, sex, smoking, body mass index (BMI), MTHFR 677C-->T polymorphism and socio-economic status. Compared with whites (10.0 [9.7-10.3] micromol/l), and allowing for confounders, Hindus had significantly higher levels of tHcy (12.1 [11.6-12.6] micromol/l). This difference was attenuated by the inclusion of vegetarianism in the model (11.3 [10.8-11.9] micromol/l). In contrast Muslims had similar tHcy levels to whites while both West Africans and Caribbeans had slightly lower levels, though differences were not significant. The reported higher levels of tHcy in South Asians are due to high levels amongst Hindus only. They are in part accounted for by their vegetarianism. These differences in tHcy are large enough to be important contributors to the risk of vascular disease and may be preventable by simple targeted population strategies.

Adult↗

PubMed2002

Mammography uptake predictors in older women.

BACKGROUND: In women aged under 65 years, socio-economic factors and general health behaviours are important predictors of mammography uptake. Little is known about whether these factors are important in older women. OBJECTIVE: To examine a broad range of mammography uptake predictors in women aged 65 and older registered with a London (UK) practice. METHODS: A survey of all female patients aged 65 and over (n = 613) in a south London practice included questions on mammography and cervical screening, general health and functional ability, socio-economic factors, mental health, health behaviours, and attitudes to health. Associations between mammography uptake and other factors were examined using logistic regression. RESULTS: The response rate was 70% (432/613). Increased age was strongly associated with decreased mammography uptake. Additionally, socio-economic factors and general health behaviours (previous cervical smear, drinking alcohol and being a non-smoker) were independently predictive of mammography uptake. Measures of physical and mental health and health attitudes were not independent predictors. Restricting analyses to the oldest women, outside the national screening programme, gave very similar results. CONCLUSIONS: In this sample of older women, socio-economic factors and general health behaviours were more predictive of mammography uptake than measures of physical and mental health or attitudes to health. Knowledge of these predictors is of increasing importance as the screening programme in the UK is extended up to age 70.

Age Factors↗

PubMed2002

Infant feeding and blood cholesterol: a study in adolescents and a systematic review.

OBJECTIVE: To examine the influence of infant feeding method on serum total cholesterol (TC) and low-density lipoprotein (LDL) cholesterol. METHODS: A cross-sectional study of 13- to 16-year-olds and a systematic review of studies (all observational) on the effects of infant feeding on cholesterol in infancy (<1 year), childhood or adolescence (1-16 years), and adulthood (> or =17 years) were conducted using random effects models. Differences are presented as breastfed-bottle-fed. A total of 1532 individuals (92% white; 55% male; mean age: 15.1 years) in 10 British towns were studied, and 37 studies with 52 observations on TC (26 in infancy, 17 in childhood or adolescence, and 9 in adulthood; corresponding figures for LDL were 7, 4, and 6) were reviewed. RESULTS: Mean TC in childhood or adolescence (including the new study) was not related to infant feeding pattern (mean TC difference = 0.00; 95% confidence interval [CI]: -0.07 to 0.07 mmol/L). However, in infancy, mean TC was higher among those breastfed (mean TC difference = 0.64; 95% CI: 0.50-0.79 mmol/L), whereas in adults, mean TC was lower among those breastfed (mean TC difference = -0.18; 95% CI: -0.30 to -0.06 mmol/L). Patterns for LDL were similar to those for TC throughout. CONCLUSIONS: Breastfeeding is associated with increased mean TC and LDL levels in infancy but lower levels in adulthood/adult life. These results suggest that breastfeeding may have long-term benefits for cardiovascular health and may have implications for the content of formula feed milks.

Adolescent↗