Incidence of hypertension and non-insulin dependent diabetes mellitus and associated risk factors in a rapidly developing Caribbean community: the St. James survey, Trinidad

OBJECTIVE: To compare the incidence rates of hypertension and non-insulin dependent diabetes mellitus in relation to ethnicity and other characteristics in a rapidly developing community. DESIGN: Prospective surveillance of a total community for five years. SUBJECTS: Cohort of 2491 men and women aged 35 to 69 years (79 percent response), of African, Indian and other (mainly Afro-European) descent. RESULTS: During surveillance, secular increases ocurred in fasting blood glucose concentrations in both sexes and in Body Mass Index (BMI) in men with apparent secular reductions in systolic blood pressure in both sexes. Incidence rates of hypertension did not differ significantly with ethnicity, ranging between 31 and 41 per 1000 person-years in men and between 27 and 32 person-years in women. In men, the incidence of diabetes (per 1000 persons-years) in Indians (24) was significantly higher than in Africans (13) and others (11). In women the diabetic incidence was similar to that for men in Indians (23) and Africans 914), but in others was twice that in men 921). In both sexes, weight gain was an important risk factor for hypertension, whereas risk for diabetes increased with BMI at baseline. The increased risk of diabetes in Indians among men was independent baseline BMI and blood glucose. CONCLUSION: Apart from the increased risk of diabetes in Indians, ethnicity had no significant influence on incidence rates hypertension and diabetes in Trinidad. Secular increases in blood glucose in both sexes and in BMI in men probably contributed to the concurrent increase in mortality from coronary heart disease in this community (AU).

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 prevalance rates of cardiac and arterial disease and diabetes mellitus were increased in the 118 (8.8 percent) 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. (AU)

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 decent who were free of coronary heart disease at entry (n=960, 69 percent 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<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. (AU)

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 prevalance of seropositivity at a titre of 1:50 using the microscopic agglutination test was 18.5 percent in Barbados and 21.9 percent 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 percent of positive cases) predominated in Barbados while Bataviae (29 percent of positive cases) predominated in Trinidad. Estimates of incidence rates for seroconversion were 2.9 percent per annum for Barbados and 3.5 percent per annum for Trinidad. Occupational risk varied between the islands, but in both cases highest seropositivity rates (greater than 50 percent) 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 island toilet was associated with an increase in seropositivity on both islands. There was little evidence of household clustering of seropositive cases. (AU)

Alcohol consumption: protection against coronary 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 percent) 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 between 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 cholesterol concentration. The overall morbidity and mortality experience in this community indicated a protective effect of alcohol against CHD, but averse health consequences from multiple causes in drinkers who were alcohol dependent. (AU)

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 (CHI) incidence among people of Indian (South Asian) descent in Trinidad, West Indies. Of 2491 individuals aged 35-69, 2215 (89 percent) were examined and 2069 (83 percent) 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, wheras alcohol consumption and HDL cholesterol concentration were inversely associated with risk after allowing for age and ethnic group. The ethnic contrast in CHD persisted when these characteristics were taken into account. In the smaller sample of women, only ethnic groups were 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. (AU)

A serological survey for leptospiral agglutinins among patients in a Barbadian general practice - abstract

Sera from 1,419 patients who attended a Barbadian general practice for a variety of complaints between 1st April and 30th April 1988 were examined for leptospiral agglutinins by the microscopic agglutination test. Sera from patients presenting with pyrexia of unknown origin, jaundice or kidney complaints, and from those whose titre was > 1:400, were also examined by the ELISA for IgM and IgG antibodies. Only one patient was diagnosed clinically as possibly having mild leptospirosis, but three others had been recently infected and some mild cases may have been missed. Altogether, 177 of the patients (12.5 percent) were positive at titres> 1:50. These were 104 of the 739 males (14 percent) and 73 of the 680 females (11 percent) (no statistically significant difference). Seropositivity tended to increase with age (p<0.01), and the highest rates were in agricultural workers (35 percent), labourers (24 percent) and non-manual outdoor workers (19 percent). The difference in seropositivity between the various indoor and outdoor occupational groups was highly significant (p<0.005). Autumnalis (31 percent of the sero postives), Panama (15 percent), Australia (14 percent) and Pyrogenes (11 percent) were the serogroups most commonly recorded among the seropositive patients. Autumnalis predominated in each of the main occupational groups except indoor non-manual workers where Panama, Pyrogenes and Australis occurred more frequently. Ninety-five per cent of the positive titres ranged between 1:50 and 1:400. Titres tended to increase with age, but there was no obvious association between higher titres and particular occupations (AU)

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 percent) were examined and 2069(83 percent) found to be clinically free of CHD at baseline> After exclusion of 71 of minority ethnic groups, 786 African, 598 Indian, 147 European 467 adults of Mixed descent were followed for CHD morbidity and mortality. In both sexes, adults of Indian descent had higher prevalences 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 thickness 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 and examination of other potential risk factors such as insulin concentration (AU)

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 percent of children with SS and SC genotypes at age 6 years and increased to affect 90 percent 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. (AU)

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 female patients. There was a striking increase in painful crises in male patients with hemoglobin levels above 8.5 g/dL (>85 g/L). High hemoglobin levels appear to be an important risk factor for painful crises.(AU)

Persistent splenomegaly and hypersplenism in sickle cell disease - abstract

Hypersplenism, arbitrarily defined as a spleen more than 3 cm below the left costal margin, associated with an haemoglobin level below 6.5 gm/dl and platelet counts below 260 x 10/1, for at least one month, occurred in 38/308 (12.3 percent) children with SS disease in a cohort study followed from birth. Comparison of clinical and haematological features in 12 patients (10 SS; 2 S§ thalassemia), with splenomegaly but without hypersplenism, indicated that hypersplenic patients had significantly shorter red cell survival (mean 3.8 days, p=0.04), lower red cell volumes (p=0.03), higher plasma volumes (p=0.003) and higher blood volumes (p=0.02). These patients also had greater diploic expansion (p = 0.05) and greater cardiomegaly (p =0.0d). Following splenectomy, there were highly significant increases in haemoglobin levels, red cell volume, red cell survival, and platelet counts, and decreases in reticulocytes and plasma volume. Height velocity over the year following splenectomy increased in 7/9 patients, with adequate data, at ages when height velocity is normally falling. Hypersplenism is characterized by severe anaemia, rapid haemolysis, and bone expansion; the metabolic cost of the erythropoietic hyperactivity may compete with the demands for normal growth. Splenectomy is the optimal method of treatment in such cases (AU)

Pregnancy in Jamaican women with homozygous sickle cell disease: fetal and maternal outcome

The outcome of 664 pregnancies in 297 Jamaican women with homozygous sickle cell (SS) disease during the period 1959-84 was reviewed. Overall, the spontaneous abortion rate was 118/1000 pregnancies, the stillbirth rate 128/1000 births, and perinatal mortality 171/1000 births. There was a striking secular increase in both spontaneous abortions and stillbirths accounted for, in part, by a trend for abortions to increase with maternal age up to the age of 30, a greater proportion of patients in the high-risk group, ages 25-29, occuring during 1980-84. Another factor contributing to the poor obstetric performance during the 1980-84 period was probably an increased survival and pregnancy rate in high-risk patients. 7 women had pregnancy-related deaths giving a pregnancy mortality rate of 1.1 percent.(AU)

Topical antibiotics in chronic sickle cell leg ulcers - abstract

Previous studies have indicated that chronic leg ulcers in homozygous sickle-cell (SS) disease usually contain at least one of the common skin pathogens, Staphylococcus aureus, Pseudomonas aeruginosa or Beta haemolytic streptococci. These organisms are usually sensitve t a mixture of neomycin, bacitracin, and polymyxin B, and a randomised controlled crossover trial of these topical antibiotics has been performed in 30 patients with chronic leg ulcers and SS disease. During the first 8 weeks, the mean ulcer area decreased to 51 percent (SD 34 percent) of initial ulcer size in the treatment group compared to 75 percent (SD 37 percent) in the control group, the difference being significant at the 5 percent level. On crossover, accelerated healing was noted in the group previously receiving control therapy, comparison of the healing rates in the two phases showing a highly significant difference (p<0.005). The results suggest that these topical antibiotics may have a place in the therapy of chronic leg ulceration associated with sickle-cell disease (AU)

Computerisation of data in a sickle cell clinic - abstract

A computer system has been set up at the Medical Research Council Laboratories, Kingston, Jamaica, to assist in patient management and statistical analysis of data collected from over 4000 patients with sickle-cell disease. The records are stored in a patient data-base which includes personal data, relative cross-referencing information, haematological and clinical observations and a directory of stored sera samples. The information is processed in three main stages: the collection and editing; storage and maintenace; and retrieval and usage. Computer programmes have also been written to show the attendance pattern of children in the "cohort" clinic, which assists in maintaining regular follow-up. The computer system has become an integral part of the work of the Unit and offers a flexible approach to research (AU)

Stilboestrol and stuttering priapism in homozygous sickle-cell disease - abstract

The vaso-occlusive process in sickle-cell disease compromises drainage of the corpora cavernosa and may cause priapism. This may consist of short, recurrent, nocturnal, "stuttering" attacks or major episodes lasting over 24 hours and usually resulting in impotence. Stuttering attacks have been reported in approximately 40 percent of adults with SS disease and, in at least one-quarter of the patients, herald a major episode. The therapy of stuttering attacks is unsatisfactory, and there are unconfirmed anecdotal reports that oral stilboestrol may be effective. A double-blind cross-over controlled study has therefore been performed in 11 patients with SS disease and stuttering priapism. Patients were randomised to either tablet A (placebo) or tablet B (stilboestrol, 5 mg), taken daily for 2 weeks. A calendar of priapism was recorded and if attacks did not cease, patients were crossed-over to the alternative modality for a further 2 weeks. The results showed that the placebo failed in all cases and that stilboestrol inhibited attacks in all 9 patients completing the study. The results were highly significant (Fishers exact test, p<0.001), indicating that oral stilboestrol is effective in terminating attacks of stuttering priapism (AU)

Delayed menarche in homozygous sickle cell disease

Age at menarche was prospectively assessed in 106 patients with homozygous sickle cell (SS) disease and the relationship with clinical, haemotological and socioeconomic factors was examined. Compared to a normal Jamaican population, the mean age at menarche in SS disease was delayed by 3.4 years. Simple regression analysis indicated that late menarche was significantly associated with low foetal haemoglobin (p<0.001), low total haemoglobin (p<0.05), low mean cell volume (p<0.05), low weight (p<0.05), low height (p<0.01) and lower social class (p<0.05). Multiple regression analyses indicated that the terms giving greatest predictive power were social class and foetal haemoglobin level (AU)

Alpha thalassemia and the hematology of homozygous sickle cell disease in childhood

Alpha thalassemia modifies the gematolic expression of homozygous sickle cell (SS) disease, resulting in increased total hemoglobin and HbA2 and decreased HbF, mean cell volume, reticulocytes, irreversibly sickled cells, and biliru-bin levels. The age at which these changes develop in children with SS disease is unknown. Ascertainment of globin gene status in a large representative sample of study the gematologic indices in nine children homozygous for Alpha thalassemia 2 (two-gene group), 90 children heterozygous for Alpha thalassemia 2 (three-gene group), and 167 children with a normal Alpha globin gene complement (four-gene group). The two-gene group had significantly lower mean cell volumes from birth, higher red cell counts from one month, lower reticulocytes from three months, and higher HbA2 levels from one year, as compared with the four-gene group. Children with three genes had intermediate indices but resembled more closely the four-gene group. Differences in total hemoglobin or in fetal hemoglobin between the groups were not apparent by eight years of age. The most characteristic differences of the two-gene group were the raised proportional HbA2 level and low mean cell volume, the latter having some predictive value for Alpha thalassemia status at birth.(AU)

Stilboestrol and stuttering priapism in homozygous sickle-cell disease

A double-blind, placebo-controlled crossover study was conducted in 11 patients with stuttering atacks of priapism and homozygous sickle-cell (SS) disease. Stilboestrol 5 mg daily was better than the placebo in preventing attacks (AU)

Pneumonia in young children with homozygous sickle cell disease: risk and clinical features

The incidence and clinical features of pneumonia have been examined in children with homozygous sickle cell (SS) disease and in age/sex matched control children with a normal haemoglobin (AA) genotype followed in a cohort study of sickle cell disease from birth. Survival curve analysis indicated a similar incidence of pneumonia in the two genotypes up to the ages of 8 months after which pneumonia became significantly more prevalent in SS disease, the relative risk exceeding a factor of four by 4 years of age. Children with SS disease were also more prone to multiple episodes.Comparison of clinical features in the two genotypes yielded no difference in sex or seasonal involvement, or in the results of bacteriological and radiological investigations. Children with SS disease and pneumonia had an increased frequency and increased duration of hospital admission, and mortality was confined to this group. It is concluded that children with SS disease have an increased prevalence of single and multiple attacks of pneumonia and that these events run a more serious clinical course than in control children. (AU)

Recurrent infections in sickle cell disease: haematological and immune studies

Some haematological and immunological indices were compared in 19 children with sickle cell disease and a history of recurrent infections and in 16 children with sickle cell disease without any known infections. The recurrent infection group had significantly greater pitted red cell counts and greater absolute monocyte counts. No differences were apparent in routine haematological indices, foetal haemoglobin, immunoglobulin, or complement levels between the groups. The interpretation of these results is discussed (AU)