Associations of whole-blood fatty acids and dietary intakes with prostate cancer in Jamaica.

OBJECTIVE: To investigate the association of whole-blood fatty acids and reported intakes of fats with risk of prostate cancer (PCa). DESIGN: Case-control study of 209 men 40-80 years old with newly diagnosed, histologically confirmed prostate cancer and 226 cancer-free men attending the same urology clinics. Whole-blood fatty acid composition (mol%) was measured by gas chromatography and diet assessed by food frequency questionnaire. RESULTS: High whole-blood oleic acid composition (tertile 3 vs. tertile 1: OR, 0.37; CI, 0.14-0.0.98) and moderate palmitic acid proportions (tertile 2: OR, 0.29; CI, 0.12-0.70) (tertile 3: OR, 0.53; CI, 0.19-1.54) were inversely related to risk of PCa, whereas men with high linolenic acid proportions were at increased likelihood of PCa (tertile 3 vs. tertile 1: OR, 2.06; 1.29-3.27). Blood myristic, stearic and palmitoleic acids were not associated with PCa. Higher intakes of dietary MUFA were inversely related to prostate cancer (tertile 3 vs. tertile 1: OR, 0.39; CI 0.16-0.92). The principal source of dietary MUFA was avocado intake. Dietary intakes of other fats were not associated with PCa. CONCLUSIONS: Whole-blood and dietary MUFA reduced the risk of prostate cancer. The association may be related to avocado intakes. High blood linolenic acid was directly related to prostate cancer. These associations warrant further investigation.

Urinary phytoestrogens and risk of prostate cancer in Jamaican men.

We evaluated the relationship of spot urinary concentrations of phytoestrogens with total prostate cancer and tumor grade in a hospital-based case-control study in Jamaica. Urine samples were analyzed for genistein, daidzein, equol (isoflavones), and enterolactone (lignan) among newly diagnosed cases (n = 175) and controls (n = 194). Urinary concentrations of enterolactone (lignan) were higher among cases. There were no significant differences in median concentrations of isoflavone excretion. Compared with non-producers of equol (reference tertile), men who produced equol were at decreased risk of total prostate cancer (tertile 2: OR, 0.42; CI, 0.23-0.75) (tertile 3: OR, 0.48; CI, 0.26-0.87) (p (trend), 0.020) and high-grade disease (tertile 2: OR, 0.31; CI, 0.15-0.61) (tertile 3: OR, 0.29; CI, 0.13-0.60) (p (trend), 0.001). Higher concentrations of enterolactone were positively related to total prostate cancer (OR, 1.85; CI, 1.01-3.44; p (trend), 0.027) as well as high-grade disease (OR, 2.46; CI, 1.11-5.46; p (trend), 0.023). There were no associations between urinary excretion of genistein and daidzein with risk of prostate cancer. Producers of equol (isoflavone) may be at reduced risk of total- and high-grade prostate cancer whereas enterolactone may increase the likelihood of disease.

An assessment of the iron status of the Jamaican population - abstract

Iron deficiency is believed to be responsible for the high prevalence of anaemia in Jamaica and the Caribbean. The groups reported to have the highest incidence of anaemia are pre-school children, pregnant and lactating females. All the data on the extent of anaemia have been based on haemoglobin measurements. This has been shown not to be an accurate estimate of body store of iron. This study was undertaken to determine the iron status of individuals under 19 years of age and of pregnant and lactating females in Jamaica. The haemoglobin, serum ferritin, transferrin saturation and free erythrocyte protoporphyrin of 2,544 people in all geographical areas and socio-economic classes, were measured and used to estimate the iron stores. The results show that approximately 50 percent of pregnant females and infants less than 2 years of age had low iron stores. There was also a high incidence of low iron stores in children between 2 and 5 years of age (approx 25 percent), and in lactating females (29 percent). Mean haemoglobin levels in all age and sex groups were lower than internationally accepted standards. In all age-sex groups, haemoglobin measurements overestimated the prevalence of iron deficiency. Although there was a good correlation between iron stores and haemoglobin levels, measurement of haemoglobin did not appear to be a good tool for screening for iron deficiency. These data indicate that iron deficiency is a major cause of anaemia in Jamaica and provide the basis for the evaluation of an iron supplementation programme, should one be embarked upon (AU)

Superoxide dismutase in red cell fractions in severe malnutrition - abstract

When fed a milk-based diet, the red cell superoxide dismutase activity (CuSODA) of malnourished children decreased. Copper supplementation prevented the decrease. This led to the suggestion that red cell CuSODA represented recent copper intake. By separating red blood cells (RBC) into fractions of different ages and measuring the CuSODA of each, it should be possible to obtain an estimate of the copper status over the life span of the RBC. There is a strong correlation between the age of RBCs and their destiny: young cells being less dense than old cells. Percoll was used to develop a method to separate cells iospycnically. Thirteen fractions were prepared with densities between 1.076 g/ml. RBCs from malnourished and healthy children were fractionated by this method, and each fraction assayed for haemoglobin and CuSODA. The total CuSODA of whole blood from each subject was also measured. Mean (and standard error) whole blood CuSODA of 15 malnourished children on admission was 3,284ñ132 i.u./gm Hb. This correlated well (r=0.69) with the sum of CuSODA in the fractions of cells (3,187ñ112). In malnourished children, there was a preponderance of heavy (old) cells. However, there was no difference in the CuSODA between the different fractions. There was a slight decrease in the CuSODA with increasing density in blood taken from three healthy children. The control children had higher CuSODA in their lighter cells. This study has shown that severely malnourished children have a preponderance of heavy (old) cells. The fact that young, less dense cells had the same CuSODA as old (more dense) cells suggests that there is no change in the copper status of severely malnourished children in the four-month (120 days) period prior to their admission to hospital (AU)

Use of red cell superoxide dismutase activity to measure copper status in severe malnutrition - abstract

As plasma copper is predominantly in the acute phase glycoprotein, ceruloplasmin, it is an unreliable index of copper status. In rats, the activity of the enzyme copper-zinc superoxide dismutase (CuSODA) is responsive to dietary manipulations of copper, but not zinc. Copper SODA was measured in 38 severely malnourished children who were rehabilitated using a cow's milk based infant formula, supplying 1.0-2.0 ænol Cu/kg body weight/day. Ninetine of the children received the formula only, while 19 received an additional 3.2 æmol copper and 31 æmol zinc/kg/day throughout their recovery. In children who did not receive the CU/Zn supplement, there was a highly significant fall in CuSODA from 1,037 ñ 70 (meanñSEM) to 784 ñ 67 æg/gHb over 33 ñ 3 days. The rate of fall was 7.5 ñ 1.7 æg/gHb/d. Thus, assuming the red cell mass turns over in 100 days, the CuSODA of the new cells being produced would be 287 æg/gHb. In children receiving copper/zinc supplement, the CuSODA rose slightly from 1,023 ñ 52 to 1,075 ñ 42 33 ñ 3 days. The dietary supplement therefore prevented the fall in CuSODA seen with a copper deficient diet. CuSODA was measured in 25 control 93 severly malnourished children on admission. Twenty-five, 9 and 3 percent of the children had CuSODA's more than 2, 3 and 4 standard deviations (respectively) below the control group. There was no relationship between any specific clinical feature (particulary hepatomegaly, oedema, skin lesions, dyspigmentation, anaemia, leucopenia), death or the subsequent rate of recovery and the CuSODA. It is concluded that (1) CuSODA is an index of copper status in humans, as it is in rats, (2) about one quarter of Jamaican malnourished children have an impaired copper status, but this is without discernible clinical correlates, (3) a cow's milk diet will result in deterioration of copper status, which is without any observed deleterious effects (AU)

Red cell glutathione peroxidase concentrations in Jamaican children with malnutrition - abstract

The activity of the seleno enzyme, red cell glutathione peroxidase (GPX) is closely related to selenium status in experimental and farm animals. Selenium deficiency causes skeletal and cardiac degeneration, hepatic necrosis and nephrosis in experimental and farm animals and cardiomyopathy in humans. As low levels of blood selenium have been reported in malnutrition, we have used GPX to assess the selenium status of 38 severely malnourished children aged 4 - 31 months (median 11.9 quartiles 9.4, 15.8). Twenty three children from a "Place of Safety" acted as controls. Fifteen of the malnourished children had normal values (25 - 60 æ/gm/Hb), 11 borderline values (20 ñ 25) and 12 subnormal values (less than 20). There were no age or sex differences. The 20 children from urban areas had higher values than the 18 from rural districts (30.8 ñ 3.0 vs 22.0 ñ 2.4). The differences among the children with marasmus, kwashiorkor and marasmic kwashiorkor were not significant (m 29.2 ñ 4.2, n = 11; K 22.3 ñ 1.7, n = 8; (MK 26.2 ñ 3.2, n = 19). Low GPX activity was associated with hepatomegaly on palpation (21.0 ñ 3.2, n = 10), skin ulceration (16.4 ñ 2.7, n = 9) and the degree of oedema (mild 31.8 ñ 3.8, n = 11; moderate 24.7 ñ 1.7, n = 5; severe 18.3 ñ 3.2 , n = 11). There was no relationship between GPX and weight or height deficits, haemoglobin, red cell appearance, clinical infection or length of antecedent history. There was a strong positive correlation between the heart diameter on chest X-ray (cardio-thoracic ratio) and GPX level (r=0.50 p <0.001). There was a tendency for children with higher GPX values to gain weight more rapidly during recovery, but this just failed to reach statistical significance (r=0.31). It is concluded that selenium status, as measured by GPX, is subnormal in about half of Jamican children with severe malnutrition. This could be associated with the clinical expression of their illness. This work was supported by the Wellcome Trust (AU)