Inverse association between docosahexaenoic acid and mortality in patients on hemodialysis during over 10 years.

We have previously conducted a cohort study to investigate n-3 polyunsaturated fatty acids (PUFAs) in red blood cells (RBCs) and risk of all-cause mortality in hemodialysis (HD) patients over 5 years and found that n-3 PUFAs, especially docosahexaenoic acid (DHA), might be an independent predictor of all-cause mortality. In the present study, we extended the study for another 5 years to determine whether DHA levels in RBCs still predict the mortality of HD patients during a 10-year study period. The study cohort consisted of 176 patients (64.1 ± 12.0 [mean ± standard deviation] years of age, 96 men and 80 women) under HD treatment. The fatty acid composition of patients' RBCs was analyzed by gas chromatography. During the study period of 10 years, 97 deaths occurred. After adjustment for 10 confounding factors, the hazard ratio of all-cause mortality of the HD patients in the highest DHA tertile (>8.1%) was 0.52 (95% confidence interval 0.30-0.91) compared with those in the lowest DHA tertile (<7.2%). However, other n-3 PUFAs such as eicosapentaenoic acid and docosapentaenoic acid (n-3) did not reveal any significant correlations. The level of DHA in RBCs could be an independent predictor of all-cause mortality in HD patients even during a long period of follow-up.

Relationships among skin conditions, mood, and polyunsaturated fatty acids of RBCs in healthy women.

Little is known about nonpathological facial skin problems at present. The aim of the present study was to investigate the relationships among facial skin conditions, mood, and the fatty acid composition of red blood cells (RBCs) in women. One hundred and thirty-two apparently healthy Japanese women aged between 20 and 60 years were recruited. Facial skin conditions were analyzed using a Robo Skin Analyzer, and the RBC fatty acid composition was also determined. Questionnaires concerning mood were administered. Forehead pigmentation was more mood-dependent (in 20s group) and less arachidonic acid (AA)-dependent (in all participants) than that in other areas of the face. Actually there was no correlation in pigmentation between the forehead and other areas of the face when adjusted for age, smoking, and drinking. Skin conditions were adversely correlated with a negative mood. α-Linolenic acid concentrations were negatively correlated with negative mood scores. Pigmentation characteristics in the forehead were independent from other areas of the face. Negative mood and AA were adversely correlated with skin conditions.

Polyunsaturated fatty acids and blood circulation in the forebrain during a mental arithmetic task.

The effects of polyunsaturated fatty acids on human cerebral blood oxygenation have yet to be extensively investigated. In this study, healthy participants (14 men, 40 women) aged between 20 and 49 years were recruited. All female participants entered the trial at the start of their menstrual cycle. Blood was sampled before measuring cerebral blood oxygenation in the prefrontal cortex (PFC) and prior to administering two kinds of questionnaires, the Profile of Mood States (POMS) and a questionnaire regarding participants' arousal level. Blood oxygenation in the PFC was continuously monitored immediately before and during the Uchida-Kraepelin Performance (UKP) test as a mental arithmetic task. Changes in the tissue oxygenation index (the ratio of oxyhemoglobin to oxyhemoglobin+deoxyhemoglobin; TOI, a simplified index for cerebral blood circulation) were measured by near-infrared spectroscopy. Multiple regression analysis was performed with sex, age, smoking and drinking as confounding factors. Eicosapentaenoic acid (EPA) was positively associated with TOI, which was positively associated with arousal level and inversely associated with negative mood (POMS). EPA and docosahexaenoic acid were inversely associated with depression-dejection (POMS) and positively associated with arousal level and overall performance in the UKP test. We suggest that EPA might increase the oxygenation level in the PFC, in turn improving various psychological parameters and performance.

Docosahexaenoic acid is an independent predictor of all-cause mortality in hemodialysis patients.

BACKGROUND: Dietary n-3 polyunsaturated fatty acids (PUFAs), docosahexaenoic acid (DHA) and eicosapentaenoic acid have been shown to reduce cardiovascular mortality. Patients on hemodialysis (HD) have a very high mortality from cardiovascular disease. Fish consumption reduces all-cause mortality in patients on HD. Moreover, n-3 PUFAs, especially DHA levels in red blood cells (RBCs), are associated with arteriosclerosis in patients on HD. The aim of this study was to determine whether DHA levels in RBCs predict the mortality of patients on HD in a prospective cohort study. METHODS: A cohort of 176 patients (64.1 ± 12.0 (mean ± SD) years of age, 96 men and 80 women) under HD treatment was studied. The fatty acid composition of their RBCs was analyzed by gas chromatography. RESULTS: During the study period of 5 years, 54 deaths occurred. After adjustment for 10 confounding factors, the Cox hazard ratio of all-cause mortality of the patients on HD in the highest DHA tertile (>8.1%, 15 deaths) was 0.43 (95% CI 0.21-0.88) compared with those patients in the lowest DHA tertile (<7.2%, 21 deaths). CONCLUSION: The findings suggest that the level of DHA in RBCs could be an independent predictor of all-cause mortality in patients on HD.