Kanako Muramatsu

Total n-3 polyunsaturated fatty acid intake is inversely associated with serum C-reactive protein in young Japanese women.

Little is known about the relation of dietary factors to circulating C-reactive protein (CRP) concentrations in young adults and non-Western populations. We cross-sectionally examined associations between dietary intake and serum CRP concentrations in young Japanese women. The subjects were 443 female Japanese dietetic students aged 18 to 22 years. Dietary intake was assessed with a validated, self-administered, comprehensive, diet history questionnaire. Serum CRP concentrations were measured by highly sensitive nephelometry. The prevalence of elevated CRP (> or = 1 mg/L) was 5.6%. After adjustment for possible confounding factors including body mass index, a significant inverse association was seen between total n-3 polyunsaturated fatty acid intake and elevated CRP. The multivariate adjusted odds ratios of elevated CRP for women with intake below and above the median (1.1% of energy) were 1.00 and 0.33 (95% confidence interval, 0.13-0.82; P = .02), respectively. Intake of eicosapentaenoic acid + docosahexaenoic acid and alpha-linolenic acid was not associated with elevated CRP concentrations (P = .62 and P = .27, respectively). Vitamin C intake was independently inversely associated with elevated CRP, although the association was nonsignificant (P = .10). No clear associations were observed for other dietary factors examined including total fat, saturated fatty acids, monounsaturated fatty acids, polyunsaturated fatty acids, total dietary fiber, soluble dietary fiber, insoluble dietary fiber, and magnesium; fruits, vegetables, and fish and shellfish; and dietary glycemic load (P = .27 to P = .99). In conclusion, total n-3 polyunsaturated fatty acid intake showed an independent inverse association with elevated serum CRP concentration in a group of young Japanese women.

Neighborhood Socioeconomic Status and Premenstrual Symptoms: A Cross-sectional Study of Young Japanese Women

Recent evidence suggests reduced levels of serotonin, which may be associated with premenstrual symptoms, among populations in socioeconomically disadvantaged areas. In this cross-sectional study, we examined the association between neighborhood socioeconomic status (SES) and premenstrual symptoms. Participants were 640 female Japanese dietetic students aged 18–22 years, residing in 210 municipalities in Japan. Neighborhood SES index was defined by seven municipal-level variables (unemployment, household overcrowding, poverty, education, income, home ownership, and vulnerable groups), with an increasing index signifying increasing neighborhood socioeconomic disadvantage. Menstrual cycle symptoms were assessed using the Moos Menstrual Distress Questionnaire, from which subscale (pain, concentration, behavioral change, autonomic reactions, water retention, and negative affect) and total scores in the premenstrual phase were calculated and expressed as percentages relative to those in the intermenstrual phase. Neighborhood SES index was positively associated with pain score in the premenstrual phase (P = 0.02). This association remained after adjustment for potential confounding factors (P = 0.008). Neighborhood SES index also showed a positive relation with water retention score in the premenstrual phase (P = 0.03), although not independently of potential confounding factors (P = 0.14). However, no association was seen between neighborhood SES index and other subscale scores or total score in the premenstrual phase (P > 0.05). In conclusion, neighborhood socioeconomic disadvantage was independently associated with higher pain in the premenstrual phase, although a clear relationship with premenstrual symptoms was not found. Considering the plausibility of the proposed mechanism, however, further investigation using more relevant neighborhood SES indicators is warranted.