Hypertension, diabetes, and obesity in Barbados: findings from a recent population-based survey

A stratified random sample of 464 persons aged 40 ato 79 years, drawn from enumeration registers in the Bridgetown area of Barbados, participated in this survey. The prevalence of hypertension (defined as systolic blood pressure of at least 160mm Hg, diastolic blood pressure of at least 95 mm Hg, or use of antihypertensive medication) was 47 percent and 43 percent for women and men, respectively. Diabetes was present in 17 percent of all subjects (18 percent of women and 15 percent of men). Of the 209 hypertensive subjects, 82 percent were aware of their blood pressure status. The proportion of previously diagnosed hypertensive subjects on medication was 72 percent for men and 68 percent for women. Fifty-three percent of men and 42 percent of women were overweight (body mass indices [weight in kilograms divided by height in meters squared] between 25 and 30. However, 30 percent of women and 10 percent of men were obese (body mass indices over 30), supporting the growing recognition of the marked gender disparity in obesity among persons of African origin in the Caribbean. Body mass index was positively associated with hypertension (OR=1.33; 95 percent CI: 1.1-1.6). Obese persons experienced a 2.6 times greater risk of hypertension compared to those with body mass indices below 25. Similar statistically significant associations were observed between diabetes and body mass index: Or comparing body mass index over 30 with body mass index under 25 was 2.5 (95 percent CI: 1.3-5.1) for all subjects, 1.0 (0.3-4.1) for men only, and 5.2 (1.9-14) for women only. Preventing obesity in this population could reduce the incidence of hypertension and diabetes by approximately 30 percent and 33 percent among men and women, respectively. (Au)

Potassium and glucose tolerance in Barbadian hypertensives, treated with thiazides - abstract

This study was designed to assess the metabolic complications of thiazide use in black Barbadian hypertensives, and in particular the relationship between plasma potassium and glucose tolerance, including glycated haemoglobin (HbA1C). Patients attending the QEH Hypertension Clinic, whose blood pressure was controlled on a thiazide diuretic and no more than two other drugs, and who gave informed consent, were randomly assigned to one of four thiazide regimes (plus their other usual drugs): bendrofluazide (B) 5mg, bendrofluazide 5 mg+ potassium (K) 39 meq daily, triamterene/hydrochlorothiazide (T/H), or amiloride/hydrochlorothiazide (A/H). Forty patients completed one-year follow-up. There were no significant differences in any metabolic variables or bloodpressures at baseline. At one year, significant differences were seen for plasma potassium between patients on B and on B + K (p<0.05), between those on B and on T/H (p 0.01) and between the T/H and A/H groups (p<0.05), using Student 't' test. When compared by analysis of variance (ANOVA), these differences were again significant (F + 3.62, p + 0.03). When data of all 40 subjects for the baseline assessment and at one year were analysed as a group, there was a strong negative correlation between change in plasma potassium (K6 - K1), and change in glycated haemoglobin (HbA1C 6 - HbA1C 1) (r = 0.62, p = < 0.01). This is the first time that thiazide-induced changes in plasma potassium, and correction of hypokalaemia have been shown to be correlated withn glycated haemoglobin, and that this relationship applies across the whole range of potassium values. If these results can be confirmed in other study populations, then perhaps thiazides can be safely used without inducing glucose intolerance or diabetes, as long as effective potassium supplementation is achieved. This has far-reaching implications for the cost-effective treatment of hypertension in the Caribbean, and other developing countries(AU)

HTLV-I serology in neurological patients at the Queen Elizabeth Hospital, Barbados - abstract

A survey of the spectrum of neurological syndromes encountered in Barbados was carried out to determine the pathogenic role of human T-lymphotropic virus (HTLV-I) infection in affected patients. Since 1989, patients with chronic neurological disorders were either recalled or were selected from new referrals to the neurology clinic at the Queen Elizabeth Hospital, Barbados. With the consent of patients, serum and CSF samples were tested for IgG antibodies to HTLV-I, using an enzyme-linked immunosorbent assay method. Positive results were confirmed by Western Immunoblotting at the CAREC Laboratories, in Trinidad. Only patients native to Barbados and the Eastern Caribbean were included in the survey. Twenty-nine (29) of 170 patients tested were serpositive for HTLV-I antibodies 18(62 percent) of the HTLV-I-positive patients had tropical spastic paraparesis (TSP). Of 21 seropositive patients who also had CFS-positive antibodies status, 16(76 percent) had TSP, 2(9.5 percent) adult T-cell leukaemia/lymphoma (ATLL), and 3 (14 percent) polymyositis, including 2 with an atypical clinical profile. HTLV-I seronegative patients included 12 (8.5 percent) with ataxia, 19(13.5 percent) with a relapsing/remitting sydrome characteristic of multiple sclerosis, 8(5.5 percent) with idiopathic intracranial hypertension and 8(5.5 percent) with stroke. HTLV-I positive associated neurological diseases in Barbados consist primarily of myelopathy (TSP). Some cases present more complex patterns of neurlogical dysfunction, associated with polymyositis. (AU)

Hypertension, diabetes mellitus and potassium status in a population sample of black Barbadians: a preliminary report - abstract

The aims of this study were to assess the previously reported hypokalaemia in black Barbadians and investigate relationships between hypertension (diastolic bloodpressue > 90mm Hg and/or systolic bloodpressure > 160mm Hg), diabetes mellitus (DM, fasting plasma glucose > 7.8 mmol/l), diet and potassium (K) status in Barbadians. A stratified random sample by sex and age (40-70 years) was obtained from enumeration registers of a geographically defined area. Of 955 persons invited, 464 (48.6 per cent) responded and they comprised 190 men and 274 women. A general and a food frequency questionnaire for 24-hr. diet recall were administered, and height, weight and bloodpressure (BP) were measured. Fasting plasma glucose, K and sodium levels were measured in blood, and urine volume, sodium and K were determined in a 24-hr. urine collection. The mean plasma of K was 3.8 mmol/l, S.D. 0.44, giving a range (mean ñ 2 S.D.) of 2.9 - 4.7 mmol/l which was almost identical to that previously reported. Both 24-hr. urinary K and sodium showed a weak negative correlation with systolic BP only. K deficiency was not clearly linked to hypertension and neither K deficiency nor current thiazide use was linked to DM. The prevalence of hypertension (25 per cent), DM (11 per cent), obesity, hypokalaemia and moderately low dietary K were high (AU)

Malnutrition and theophylline clearance in the elderly

Thirteen elderly, clinically malnourshed (mean age 75.7) were studied for theophylline clearance before and after treatment for malnutrition. Theophylline half-life and clearance values were within normally reported values though the mean clearance value was greater (p<0.001) than that in a control group. Following treatment for malnutrition the clearance increased by 36 percent (p<0.05). This is an indication that the requirements of geriatric patients may need revision upon the nutritional rehabilitation which is expected following admission to appropriate facilities (AU)

Theophylline clearance in malnourished elderly subjects - abstract

Many factors, including age and nutritional status, can affect drug metabolic rates. This study was designed to assess the metabolising capacity for the anti-asthmatic drug, theophylline, in malnourished elderly subjects before and after nutritional rehabilitation. Thirteen elderly, clinically malnourished subjects (aged 65-88 yrs.) were studied three to four days after admission to hospital for social reasons, and again after ten days of re-feeding with a high calorie, high protein diet. Theophylline half-life (T«) and clearance (CI) were determined from blood samples taken between 3 and 24 hours after a dose of 3.5 mg/kg. Malnutrition was assessed clinically and by serum albumin, haemoglobin and thyroid binding pre-albumin (TBPA). Serum albumin and TBPA were positively correlated and both increased after re-feeding. Theophylline Tu« and Cl values were within reported ranges. Half-lives were the same as those of healthy adult controls, but clearances were greater. Cigarette smokers were among the slowest, suggesting some other factor of malnutrition or acute hospitalisation may accelerate metabolism. On re-feeding, clearances increased by 37 percent, showing a great capacity of the elderly to respond to dietary supplementation; the subjects who were most malnourished had the lowest Cl rates and responded with the greates increase. These results have important implications for the selection of drug dose regimes for elderly hospitalised patients as the drug requirements may changed considerably during rehabilitation (AU)

Nutritional status of medical admissions - abstract

Following the observation of an apparently high prevalence of poor nutritional status in elderly hospital admissions a prospective survey was carried out on two medical wards at the Queen Elizabeth Hospital, Barbados. Sixty consecutive admissions had haemoglobin, serum albumin and serum trasferrin levels assayed, and weights and heights measured. Albumin was measured by immunoelectrophoressis and transferrin by radial diffusion methods. Patients with renal or liver disease, blood loss or diseases of the haemopoietic system were excluded. The mean age of patients admitted was 59.3 years ñ 17.4 (S.D.), (range 13 to 85). Laboratory indices for all patients were: haemoglobin level 10.2g/dl ñ 4.0 (women) and 11.7gm/dl ñ 2.3 (men), albumin level 37.4 g/l ñ 7.3 (normal range at QEH 29-45) and transferrin level 2.2 ñ 0.5 g/l (normal range 2.0-4.0). There was a significant negative correlation between serum albumin and age (r=-0.36;p<0.025), and between haemoglobin and age (r= -40; p<0.025). The haemoglobin level was more strongly correlated with age in men than in the whole group (r = -0.48) or in women (r = 0.28). Serum transferrin levels showed the strongest correlation with age (r = -0.48) although it was measured in only 18 subjects (p<0.05). Serum albumin and transferrin levels showed a significant positive correlation with each other as expected (r = 0.47;p<0.05). Ther was no correlation between albumin and haemoglobin levels or between body mass index (weight devided by heightý) and age. Neither haemoglobin nor albumin levels are ideal indices of malnutrition. Transferrin is widely accepted to be a better index of protein deficiency. The negative correlation of all three with age in this survey provides strong evidence that elderly patients admitted to hospital with acute medical problems are ess well-nourished than their younger counterparts. Since nutritional status may affect resistance to infection and stress, malnutrition may play a role both in precipitating illness in the elderly and in determining the outcome. Malnutrition in the elderly in the Caribbean merits the attention of preventive as well as curative services (AU)

Reference ranges for thirteen biochemical parameters in Barbadian blood donors - abstract

At the Queen Elizabeth Hospital, the reference ranges of thirteen (13) biochemical constituents in plasma where determined, using blood donors. Prior to the establishment of these reference ranges, we were using either the European or the North American reference ranges. Differences between the Barbadian population and both of these groups are expected since we have different diets and optimal nutritional standards. Significant differences were found to be present in the plasma potassium, albumin and urate levels (p<0.01). In Jmaica, it has been shown that a reversal of the usual albumin/globulin ratio is associated with the nutritional and infectious disease status of that population. The total protein and albumin ranges appear to be wide. This is not a reflection of the precision of the methods used, but may be due to the fact that we sampled a fairly large cross-section of the population, with varying dietary habits. The low potassium range need further investigation. It must, however, be mentioned that many of our patients have a plasma potassium value at the lower limits of the European and North American reference ranges without any apparent symptoms of hypokalaemia. The explanation for the low plasma potassium value may be dietary deficiency, as the traditional Barbadian diet in the lower socio-economic group is low in fresh fruits and vegetables (AU)