PubMed HealthSearch

Biomedical subjects

G H Maude

Publications and source records attributed to G H Maude.

At least 19 recordsLinked to original sources

Coagulation abnormalities and ivermectin.

Prothrombin ratios were measured 13-16 days after treatment in 148 subjects from Sierra Leone taking part in a double-blind placebo-controlled trial of ivermectin. Prolonged prothrombin ratios were observed more frequently in the ivermectin group, although this difference was not significant and no patients suffered bleeding complications. Further investigation of these patients failed to reveal any abnormality of liver function, although factor VII and II levels were reduced in most affected individuals, suggesting interference with vitamin K metabolism. Ivermectin has a minimal effect on coagulation and concern about mass treatment for this reason appears to be unjustified.

Adolescent

Effects of repeated doses of ivermectin on ocular onchocerciasis: community-based trial in Sierra Leone.

Ivermectin seems to be a safe and effective treatment for onchocerciasis when given in a single dose, but less is known about the effects of repeated doses. Also, there seem to be differences in its effectiveness in anterior and posterior segment ocular disease. The ocular effects of ivermectin were studied in 586 villagers who were taking part in a double-blind, placebo-controlled, randomised trial in Sierra Leone. Only those who had received four doses, with 6-month intervals, of ivermectin or placebo were eligible. The 296 ivermectin-treated subjects and the 272 who received placebo were comparable with respect to age, sex, Onchocerca infection, blindness, and visual impairment before treatment. After treatment, the ivermectin group had less anterior segment disease than the placebo group, with significantly lower prevalences of microfilariae in the anterior chamber and cornea, and punctate keratitis (all p less than 0.001), and iritis (p less than 0.05). There was no significant difference in the prevalence of sclerosing keratitis, optic atrophy, or chorioretinitis between the groups. Visual acuities tended to be better in the ivermectin group, but the difference was not significant. There was a small but significant (p less than 0.01) excess of vascular sheathing in the ivermectin group. These differences persisted when subjects who were blind or visually impaired at baseline were excluded from analysis. The long-term effects of ivermectin, particularly on posterior segment disease, need further evaluation. In the mean time, the mass distribution of ivermectin should be promoted for all communities with hyperendemic onchocerciasis at risk of anterior segment disease.

Adolescent

Leptospiral infection: a household serosurvey in urban and rural communities in Barbados and Trinidad.

A longitudinal study of leptospiral agglutinins in subjects five years of age and over was undertaken in Trinidad and Barbados between 1980 and 1982. Households were sampled randomly from one urban and two rural communities on each island, giving a total of 576 eligible individuals in Barbados and 524 in Trinidad. Participants were examined three times at approximately annual intervals. The prevalence of seropositivity at a titre of 1:50 using the microscopic agglutination test was 18.5% in Barbados and 21.9% in Trinidad. Prevalence increased steeply with age in both sexes and was higher in males than females on both islands. There was a marked difference in predominating serogroups on the two islands--Autumnalis (42% of positive cases) predominated in Barbados while Bataviae (29% of positive cases) predominated in Trinidad. Estimates of incidence rates for seroconversion were 2.9% per annum for Barbados and 3.5% per annum for Trinidad. Occupational risk varied between the islands, but in both cases highest seropositivity rates (greater than 50%) were found in outdoor labourers and lowest were found in indoor non-manual workers and urban homeworkers. In Barbados seroprevalence was higher among persons who cleared drains or who had contact with livestock. Lack of an inside toilet was associated with an increase in seropositivity on both islands. There was little evidence of household clustering of seropositive cases.

Adolescent

Evaluation of the nutritional status of 1st-year school children in Campinas, Brazil.

We present findings from a study of nutritional status amongst 1st year primary school children in Brazil. The study was based on a 10% stratified random sample of children in Campinas, Sao Paulo State. The primary schools in the city were grouped into four socio-economic strata (high, medium, low and very low) based on the type of school maintenance (private or maintained by the local or by the State government) and the socio-economic characteristics of the school's catchment area. The nutritional status of 1942 children was assessed by looking at the distributions of z-scores of weight-for-age, height-for-age and weight-for-height in relation to growth charts of the National Center for Health Statistics reference population. In the overall population, 22% of the children were found to be stunted (z-score of height-for-age less than -1.0), 15% wasted (z-score of weight-for-height less than -1.0), 22% underweight (z-score of weight-for-age less than -1.0) and 5% overweight (z-score of weight-for-height greater than 2.0). These figures represent an excess of 6% of stunted children and also 6% of underweight children in comparison with the expected values in the NCHS reference population, and an excess of 2% overweight. The data were analysed by age, sex, ethnic group and socio-economic level. Both stunting and low weight-for-age were observed in 32% of children from the very low socio-economic level, with the highest percentages amongst the oldest children. A total of 11.6% of children from the high socio-economic stratum were obese. These results emphasize the need for different programmes to deal with nutritional problems in different groups of the population.

Age Factors

Alcohol consumption: protection against coronary heart disease and risks to health.

In a prospective cardiovascular study of 1341 Trinidadian men aged 35-69 years undertaken between 1977 and 1986, the baseline prevalence rates of cardiac and arterial disease and diabetes mellitus were increased in the 118 (8.8%) who had been but were no longer regular drinkers. This finding suggested that awareness of these disorders was a discouragement to drinking alcohol. When this group and all with coronary heart disease (CHD) or diabetes at entry were excluded, a significant inverse trend was found between alcohol consumption in the week before recruitment and risk of CHD across the subsequent average follow-up of 7.5 years. Men who had taken 5-14 drinks had about half the CHD risk of those who had had no alcohol, even after allowance for age, ethnicity, smoking, blood pressure and serum cholesterol concentration. The overall morbidity and mortality experience in this community indicated a protective effect of alcohol against CHD, but adverse health consequences from multiple causes in drinkers who were alcohol dependent.

Adult

High density lipoprotein cholesterol concentration as a predictor of coronary heart disease in West Indian men.

STUDY OBJECTIVE: The aim of the study was to determine whether the inverse association between high density lipoprotein cholesterol concentration and risk of coronary heart disease described in people of European stock was also present in other racial groups. DESIGN: The study was a prospective population survey. Cardiovascular risk factors were examined, including fasting serum lipid estimation (obtained at recruitment). SETTING: This was a community based study within a defined survey area in Trinidad. PARTICIPANTS: All men aged between 35 and 69 years within the survey area were identified and followed between 1977 and 1986. Analysis was confined to those of African, Asian Indian, and mixed descent who were free of coronary heart disease at entry (n = 960, 69% of age eligible men in the survey population). MEASUREMENTS AND MAIN RESULTS: 64 men developed coronary heart disease during the study period. A strong inverse curvilinear relation was found between high density lipoprotein cholesterol and coronary heart disease incidence (p less than 0.005), independent of age or other relevant characteristics including low density lipoprotein cholesterol. CONCLUSIONS: A low serum concentration of high density lipoprotein cholesterol is a risk factor for coronary heart disease in non-whites as well as in whites.

Adult

Ethnicity and other characteristics predictive of coronary heart disease in a developing community: principal results of the St James Survey, Trinidad.

A ten-year community survey was undertaken to investigate the high coronary heart disease (CHD) incidence among people of Indian (South Asian) descent in Trinidad, West Indies. Of 2491 individuals aged 35-69 years, 2215 (89%) were examined and 2069 (83%) found to be clinically free of CHD at baseline. After exclusion of 71 of minority ethnic groups, 786 African, 598 Indian, 147 European and 467 adults of Mixed descent were followed for CHD morbidity and mortality. In both sexes, adults of Indian origin had higher prevalence rates of diabetes mellitus, a low concentration of high-density lipoprotein (HDL) cholesterol, and recent abstinence from alcohol than other ethnic groups. Indian men also had larger skinfold thicknesses than other men. In participants free of CHD at entry, the age-adjusted relative risk of a cardiac event believed due to CHD was at least twice as high in Indian men and women as in other ethnic groups. In men, blood pressure, diabetes mellitus and low-density lipoprotein (LDL) cholesterol concentration were positively and independently related to risk of CHD, whereas alcohol consumption and HDL cholesterol concentration were inversely associated with risk after allowing for age and ethnic group. The ethnic contrasts in CHD persisted when these characteristics were taken into account. In the smaller sample of women, only ethnic group was predictive of CHD as defined. The failure of point estimates of risk to explain the high CHD incidence in Indians calls for focus on age of onset of risk and examination of other potential risk factors such as insulin concentration.

Adult

Onchocerciasis in Sierra Leone.2: A comparison of forest and savanna villages.

Very little of the original primary forest remains in Sierra Leone and the savanna is mainly woodland or a forest-savanna mosaic. The prevalence of microfilariae of Onchocerca volvulus, nodules and moderate or severe skin lesions was higher in forest than savanna villages. In forest villages the prevalence of microfilariae was 71.8% at the iliac crest, 36.6% (outer canthus), 12.8% (cornea) and 34.1% in the anterior chamber of the eye. Corresponding figures for the savanna villages were 51.9%, 20.5%, 5.6% and 21.8%. The overall prevalence of nodules in the forest and savanna was 70.5% and 53.2% respectively, while the prevalence of head and upper body nodules was 14.8% (forest) and 11.0% (savanna). The prevalence of moderate or severe skin lesions was 17.7% in forest and 13.0% in savanna villages. Lesions of the groin and scrotum were few in both zones. In persons aged 30 years or more the prevalence rates of severe eye lesions--sclerosing keratitis, iritis, optic atrophy and choroidoretinitis--were 4.3%, 16.1%, 13.9% and 14.8% respectively in forest villages. Corresponding figures for the savanna villages were 3.7%, 8.7%, 14.2% and 11.3%. Males were more commonly affected than females. At least one of these lesions was found in 32% persons in forest and 24% in savanna villages.

Adolescent

Onchocerciasis in Sierra Leone 3: Relationships between eye lesions and microfilarial prevalence and intensity.

The relationship between severe onchocercal eye lesions (iritis, sclerosing keratitis, optic atrophy and choroidoretinitis) and (i) the prevalence and intensity of microfilariae (mf) of Onchocerca volvulus in skin snips from the iliac crest and outer canthus, and (ii) the prevalence of mf in the cornea and anterior chamber of the eye, was studied in 1414 persons from forest and savanna villages and 312 attenders at eye clinics. Ecologically the savanna of Sierra Leone more closely resembles the forest than the dry Sudan-savanna areas of West Africa, and in persons aged 30 years or more the combined prevalence of anterior segment lesions (iritis and sclerosing keratitis) was higher in the forest villages (20.6%) than in the savanna (12.7%). The higher loads of mf found in the forest compared to savanna villages could explain these results. Prevalence rates for posterior segment lesions (optic atrophy and choroidoretinitis) were 28.1% and 22.6% in the forest and savanna respectively. Although in villages from both zones there was a close association between mf in the anterior chamber and optic atrophy, other associations between posterior segment lesions and mf were either not significant or weak. In contrast, there was a strong association between anterior segment lesions and mf in the eye and the concentration of mf at the outer canthus. This association was stronger for iritis than for sclerosing keratitis.

Adolescent

Sickle cell retinopathy in Jamaican children: further observations from a cohort study.

Serial retinal examinations were performed in children aged 5 years and older and fluorescein angiography/angioscopy in children 6 years and older participating in a cohort study of sickle cell disease. There were 1229 patient years of observation among 389 children aged 5-13 years. Peripheral retinal vessel closure was present in approximately 50% of children with SS and SC genotypes at age 6 years and increased to affect 90% of children by age 12 years. A matched pair analysis, comparing groups with minimal and complete closure, indicated that complete closure was associated with significantly lower total haemoglobin and fetal haemoglobin levels and significantly lower weight in SS disease, whereas in SC disease the risk factors appeared to be high mean cell volume and low platelet count. Proliferative retinopathy was rare, occurring only once in an 8-year-old boy with SC disease, despite 592 patient years of observation in children over this age.

Adolescent

Epidemiological studies of onchocerciasis in forest villages of Sierra Leone.

Results are presented for five villages in the forest zone of Sierra Leone in which forest onchocerciasis was considered to be a significant health problem. All five villages were found to be hyperendemic and 85% (682/803) of persons were found to have at least one sign of onchocerciasis. The emergence of microfilariae from skin snips (iliac crest and/or canthus) or the presence of nodules accounted for 96.5% of all persons positive for onchocerciasis. The prevalence of nodules from all body sites was 70.5% and of elephantiasis, hanging groin and skin lesions (moderate and severe) was 0.4%, 0.3% and 5.3% respectively. Analysis of eye lesions (the most serious clinical manifestation of the disease) was restricted to persons aged 30 years and over since this gives a better indication of the public health importance of onchocerciasis than analysis in the overall population. This gave prevalence rates of onchocercal blindness of 4.5% (both eyes) and 2.8% (one eye only). Rates for the four potentially blinding eye lesions were sclerosing keratitis (4.1%), iritis (16.5%), optic atrophy (13.8%) and choroidoretinitis (14.4%). Rates in males were approximately twice as high as those in females.

Adolescent

Epidemiological studies of onchocerciasis in savanna villages of Sierra Leone.

The overall prevalence of onchocerciasis was 78% and 73% in three villages of the woodland savanna of Koinadugu and four villages of the savanna-forest mosaic of Kambia respectively. The total number of persons examined was 611. In Koinadugu the prevalence of microfilariae of Onchocerca volvulus in skin snips from the iliac crest and canthus was 51.3% and 22.5% respectively while corresponding figures for Kambia were 52.2% and 19.3%. The pattern of clinical manifestations were similar in both districts, the overall rates for nodules, skin lesions (moderate and severe) and leg elephantiasis being 53.2%, 12.5% and 0.3% respectively. No cases of hanging groin were seen. The prevalence of onchocercal eye lesions was lower in the present surveys than in our own findings in Guinea or the findings of other investigators in the Guinea or Sudan savanna of West Africa. In the present study prevalences of the fourmain blinding eye lesions in persons aged 30 years or more were sclerosing keratitis (3.7%), iritis (8.7%), optic atrophy (14.2%) and choroidoretinitis (11.3%), and the prevalence of blindness was 4.2% (both eyes) and 2.0% (one eye). Males were more commonly affected than females. Further entomological studies are needed to elucidate the relative role played by the different cytospecies of Simulium damnosum s.l. in the transmission of onchocerciasis in the savanna of Sierra Leone.

Adolescent

Topical antibiotics in chronic sickle cell leg ulcers.

A randomized, controlled, trial of a topical antibiotic preparation (neomycin, bacitracin, and polymyxin B) was performed in 30 patients with homozygous sickle cell (SS) disease and chronic leg ulceration. Over a period of 8 weeks, the reduction in ulcer size was significantly (P less than 0.05) greater in the treatment group than in the control group. The results suggest that these topical antibiotics may contribute to the therapy of chronic leg ulceration associated with sickle cell disease.

Administration, Topical

The haematology of steady state homozygous sickle cell disease: interrelationships between haematological indices.

The interrelationships between steady state haematological variables in 825 patients with homozygous sickle cell (SS) disease have been examined. On simple correlation coefficient analysis HbA2 correlated negatively with both HbF and MCV, red cell count (RBC) correlated positively with total haemoglobin and negatively with MCV and reticulocytes, and MCV correlated positively with reticulocytes. Less consistent were positive correlations between HbA2 and RBC, between HbF and both MCV and haemoglobin, between MCHC and MCV, and a negative relationship between haemoglobin and reticulocyte count. Partial correlation coefficient analysis clarified some of these relationships. In principal component analysis, the first component weighted positively on Hb and RBC and negatively on reticulocytes and possibly reflected the haemolytic rate. The second component weighted positively on HbF and MCV and negatively on HbA2 and may be related to alpha thalassaemia status. The third component weighted almost exclusively on MCHC and may relate to the degree of intracellular polymerization of HbS. These three components accounted for approximately 75% of the total variation in the haematological data.

Adolescent

The painful crisis of homozygous sickle cell disease. A study of the risk factors.

Some epidemiologic features of the painful crisis in homozygous sickle cell disease were examined in a retrospective study of 995 painful crises. Previously reported associations with cold weather and pregnancy were confirmed. There was a striking increase in painful crises in male patients between the ages of 15 and 25 years, whereas female patients showed little age-related change. The frequency of painful crises correlated positively with hemoglobin levels and reticulocyte counts in both sexes and negatively with mean corpuscular volume in female patients. There was a striking increase in painful crises in male patients with hemoglobin levels above 8.5 g/dL (greater than 85 g/L). High hemoglobin levels appear to be an important risk factor for painful crises.

Acute Disease

Clinical presentation of sickle cell-hemoglobin C disease.

Early symptoms were observed in a representative sample of 166 children with sickle cell-hemoglobin C disease diagnosed at birth. Symptoms were uncommon in the first year of life; in approximately 50% specific symptoms had developed by 5 years, but 22% remained without specific symptoms to 10 years. The age at presentation was significantly earlier in patients with low hemoglobin F levels, but was not influenced by heterozygous alpha-thalassemia-2. Painful crisis was the initial manifestation in 77% of the children; other symptoms included dactylitis (14%) and pneumococcal septicemia and acute splenic sequestration (4% each). The commonest nonspecific symptom was acute chest syndrome. The relatively mild early clinical course of sickle cell-hemoglobin C disease indicates that neonatal diagnosis does not have the same urgency as for homozygous sickle cell disease.

Acute Disease