Association of adulthood weight gain with circulating adipokine and insulin resistance in the Japanese population.

BACKGROUND/OBJECTIVES: Although adipokines and insulin resistance are known to be correlated with body fatness, it is unclear whether they are independently related to weight gain experience. We examined the associations of serum adipokines and marker of insulin resistance with past weight gain during adulthood by taking the degree of attained body mass index (BMI) level into consideration. SUBJECTS/METHODS: Subjects were 399 Japanese municipal employees, aged ⩾ 30 years, who participated in a health survey. Serum adipokines were measured using a Luminex suspension bead-based multiplexed array. Weight change during adulthood was calculated as the difference between measured current weight and recalled weight at the age of 20 years. Multiple regression was performed to calculate mean adipokine levels and homeostasis model assessment of insulin resistance (HOMA-IR) according to weight gain (< 5 kg, 5-9.9 kg, or ⩾ 10 kg) with adjustment for current BMI. RESULTS: Weight gain from the age of 20 years was significantly and positively associated with leptin levels even after adjustment for current BMI (P for trend < 0.001), whereas it was significantly and inversely associated with adiponectin levels in a BMI-adjusted model among subjects aged ⩾ 40 years (P for trend=0.03). Weight gain was associated with HOMA-IR in a BMI-unadjusted model (P for trend < 0.001), but this association was largely attenuated after adjustment for BMI. Resistin, plasminogen activator inhibitor-1 and visfatin were not associated with past weight gain. CONCLUSIONS: Results suggest that a large weight gain during adulthood is associated with higher leptin and lower adiponectin levels independently of the degree of attained BMI level.

Serum pyridoxal concentrations and depressive symptoms among Japanese adults: results from a prospective study.

BACKGROUND/OBJECTIVES: Vitamin B6 is suggested to have a protective role against depression. However, the association between vitamin B6 intake and depression remains inconclusive, and few studies have examined the relationship between circulating vitamin B6 concentrations and depressive symptoms. Here, we investigated the cross-sectional and prospective associations between serum pyridoxal concentrations and depressive symptoms among Japanese workers. SUBJECTS/METHODS: Participants were 422 municipal employees (aged 21-67 years) who participated in a baseline survey in 2006 for cross-sectional analysis, and 210 subjects without depressive symptoms at baseline (2006) who completed both baseline and follow-up (2009) surveys for prospective analysis. Depressive symptoms were assessed using the Center for Epidemiologic Studies Depression (CES-D) scale. Logistic regression analysis was used to estimate the odds ratio of depressive symptoms (CES-D scale of ≥ 19) according to tertile of serum pyridoxal with adjustment for potential confounding variables. RESULTS: In the cross-sectional analysis, serum pyridoxal concentrations were significantly associated with a decreased prevalence of depressive symptoms (P for trend=0.03); the multivariable-adjusted odds ratio of depressive symptoms for the highest tertile of pyridoxal was 0.54 (95% confidence interval 0.30-0.96) compared with the lowest tertile. In longitudinal analyses, higher serum pyridoxal concentrations at baseline were associated with a trend toward reduced depressive symptoms after 3 years; the multivariable-adjusted odds ratio of depressive symptoms for the highest versus the lowest tertile of pyridoxal concentration was 0.55 (95% confidence interval 0.13-2.32). CONCLUSIONS: A higher vitamin B6 status may be associated with a decreased risk of depressive symptoms in Japanese.

Dietary patterns and type 2 diabetes in Japanese men and women: the Japan Public Health Center-based Prospective Study.

BACKGROUND/OBJECTIVE: Dietary patterns in Western populations have been linked to type 2 diabetes, but the association of distinctive dietary patterns of Japanese population remains unclear. We prospectively investigated the association between dietary patterns and risk of developing type 2 diabetes among Japanese adults. SUBJECTS/METHODS: Participants were 27, 816 men and 36,889 women aged 45-74 years who participated in the second survey of the Japan Public Health Center-based prospective study and had no history of diabetes. Dietary patterns were derived by using principal component analysis of the consumption of 134 food and beverage items ascertained by a food frequency questionnaire. Odds ratios of self-reported physician-diagnosed type 2 diabetes over 5 year were estimated using logistic regression analysis. RESULTS: A total of 1194 new cases (692 men and 502 women) of type 2 diabetes were self-reported. We identified three dietary patterns: prudent, westernized and traditional Japanese patterns. Any dietary pattern was not significantly associated with type 2 diabetes risk after adjustment for covariates in both men and women. The multivariate-adjusted odds ratios (95% confidence interval) for type 2 diabetes for the highest versus lowest quartile of each dietary pattern score in men and women, respectively, were 0.93 (0.74-1.16) and 0.90 (0.69-1.16) for the prudent pattern, 1.15 (0.90-1.46) and 0.81 (0.61-1.08) for the westernized pattern, and 0.97 (0.74-1.27) and 0.87 (0.66-1.15) for the traditional pattern. CONCLUSIONS: Although a small protective effect of the prudent dietary pattern cannot be excluded, dietary patterns may not be appreciably associated with type 2 diabetes risk in Japanese.

Serum 25-hydroxyvitamin D and markers of insulin resistance in a Japanese working population.

BACKGROUND/OBJECTIVES: The association between vitamin D status and insulin resistance (IR) has been less studied among Asians, and it remains elusive whether calcium could modify such an association. We examined the association of serum 25-hydroxyvitamin D (25(OH)D) concentrations with IR markers and the potential effect modification by calcium intake among a Japanese population. SUBJECTS/METHODS: The authors analyzed data (n=494) from a cross-sectional survey conducted in 2009 among a Japanese working population aged 20-68 years. Fasting serum 25(OH)D and insulin, as well as fasting plasma glucose were determined, and homeostatic model assessment of IR (HOMA-IR) was calculated. Calcium intake was assessed using a validated diet history questionnaire. Multiple linear regression was done with adjustment of potential confounding variables. RESULTS: Fasting insulin and HOMA-IR were significantly inversely associated with 25(OH)D concentration across quartiles of 25(OH)D after fully adjusting for covariates (P(trend)=0.04 and 0.02, respectively). Across clinically relevant categories of 25(OH)D, compared with participants in the vitamin D sufficiency group, those in the vitamin D insufficiency group had a 5% higher HOMA-IR score, and those in the hypovitaminosis D group had an 18% higher HOMA-IR score (P(trend)=0.01). In an analysis by calcium intake, the HOMA-IR score was highest among participants with both a low calcium intake and lowest 25(OH)D concentrations, with significant inverse trend being observed in the group with lower calcium intake (P(trend)=0.02). CONCLUSIONS: Our findings suggest that low vitamin D status is associated with IR among Japanese adults.

Magnesium intake and type II diabetes in Japanese men and women: the Japan Public Health Center-based Prospective Study.

This study examined the association between magnesium intake and type II diabetes risk among Japanese adults. Participants were 25 872 men and 33 919 women aged 45-75 years who had no history of diabetes. Magnesium intake was ascertained using a 147-item food frequency questionnaire. Odds ratio of self-reported physician-diagnosed type II diabetes over 5 years was estimated using logistic regression analysis. A total of 1114 new cases of type II diabetes were self-reported. Magnesium intake was not significantly associated with type II diabetes in either men or women. The multivariable-adjusted odds ratios (95% confidence intervals) of type II diabetes for the highest versus lowest quintile of magnesium intake were 0.86 (0.63-1.16) and 0.92 (0.66-1.28) for men and women, respectively. Although a small effect cannot be excluded in men, magnesium intake may not be appreciably associated with risk of type II diabetes for Japanese adults.

Dietary patterns and depressive symptoms among Japanese men and women.

OBJECTIVE: Although several studies have reported associations of depressive state with specific nutrients and foods, few studies examined the association with dietary patterns in adults. We investigated the association between major dietary patterns and depressive symptoms in Japanese. METHODS: Subjects were 521 municipal employees (309 men and 212 women), aged 21-67 years, who participated in a health survey at the time of periodic checkup. Depressive symptoms were assessed using the Center for Epidemiologic Studies Depression (CES-D) Scale. Dietary patterns were derived by using principal component analysis of the consumption of 52 food and beverage items, which was assessed by a validated brief diet history questionnaire. Logistic regression analysis was used to estimate odds ratios of depressive symptoms (CES-D >or=16) with adjustment for potential confounding variables. RESULTS: We identified three dietary patterns. A healthy Japanese dietary pattern characterized by high intakes of vegetables, fruit, mushrooms and soy products was associated with fewer depressive symptoms. The multivariate-adjusted odds ratios (95% confidence intervals) of having depressive symptoms for the lowest through highest tertiles of the healthy Japanese dietary pattern score were 1.00 (reference), 0.99 (0.62-1.59) and 0.44 (0.25-0.78), respectively (P for trend=0.006). Other dietary patterns were not appreciably associated with depressive symptoms. CONCLUSIONS: Our findings suggest that a healthy Japanese dietary pattern may be related to decreased prevalence of depressive status.

Serum folate and homocysteine and depressive symptoms among Japanese men and women.

BACKGROUND/OBJECTIVES: Folate and homocysteine have been implicated to have a role in depression. However, results of epidemiologic studies on this issue have been inconsistent. The objective of this study was to clarify the association between serum folate and homocysteine concentrations and depressive symptoms in Japanese adults. SUBJECTS/METHODS: We analyzed cross-sectional data for 530 municipal employees (313 men and 217 women), aged 21-67 years, who participated in a health survey at the time of periodic checkup. Depressive symptoms were assessed using the Center for Epidemiologic Studies Depression (CES-D) scale. Logistic regression analysis was used to estimate odds ratios of depressive symptoms (CES-D scale scores of >or=16) with adjustment for potential confounding variables. RESULTS: In total, 113 men (36.1%) and 79 women (36.4%) had depressive symptoms. A higher serum folate was associated with a decreased prevalence of depressive symptoms in men. The multivariate-adjusted odds ratios (95% confidence interval) of depressive symptoms for the lowest to highest quartiles of serum folate were 1.00 (reference), 0.53 (0.27-1.03), 0.33 (0.16-0.68) and 0.51 (0.25-1.03), respectively (trend P=0.03). Furthermore, the data suggested a positive association between serum homocysteine and depressive symptoms in men (trend P=0.06). In women, neither folate nor homocysteine was associated with depressive symptoms. CONCLUSIONS: Low serum folate may be related to an increased prevalence of depressive symptoms in Japanese men.

Weight change and all-cause, cancer and cardiovascular disease mortality in Japanese men and women: the Japan Public Health Center-Based Prospective Study.

BACKGROUND: It is unclear whether weight change during adulthood influences subsequent mortality in Asian populations, who have a relatively lean body mass. OBJECTIVE: To assess the relation of weight change over 5 years to all-cause, cancer and cardiovascular disease mortality among Japanese men and women. DESIGN: Subjects were 36 220 men and 44 091 women aged between 45 and 75 years without a history of serious disease at baseline. Weight change was calculated as the difference of body weight between two surveys with a 5-year interval. RESULTS: During 699 963 person-years of follow-up, we identified 4232 deaths of all-cause, 1872 cancer deaths and 1021 cardiovascular deaths. The relation between weight change and all-cause mortality was reverse J-shaped. Multivariate hazard ratios (95% confidence interval) for weight loss of 5 kg or more versus weight change of less than 2.5 kg were 1.62 (1.45-1.81) in men and 1.76 (1.51-2.05) in women, whereas those for weight gain of 5 kg or more were 1.40 (1.22-1.59) in men and 1.25 (1.02-1.54) in women. These associations remained statistically significant even after the exclusion of deaths in the first 3 years of follow-up. The weight change-mortality association was pronounced in underweight persons or in nonsmoking men. The risk of cancer mortality increased in both men and women who lost weight by 5 kg or more. With regard to cardiovascular disease, mortality risk tended to increase with weight loss both in men and women, whereas its increase with weight gain was observed only in women. CONCLUSIONS: A large weight change, both loss and gain, was associated with an increased risk of mortality. Weight loss and gain may be predictors of early death in apparently healthy adult Japanese.

Association between serum 25-hydroxyvitamin D and depressive symptoms in Japanese: analysis by survey season.

Both depressive symptoms and vitamin D insufficiency are common during winter. This study examined the association between serum 25-hydroxyvitamin D and depressive symptoms by survey season. Subjects were 527 municipal employees aged 21-67 years of two municipal offices in Japan. Overall, there was no measurable association. However, in the workplace surveyed in November, multivariate-adjusted odds ratios (95% confidence interval) of having depressive symptoms (Center for Epidemiologic Studies Depression score of >or=16) for the lowest through highest quartiles of serum 25-hydroxyvitamin D were 1.00 (reference), 0.84 (0.45-1.58), 0.83 (0.44-1.58) and 0.59 (0.30-1.15), respectively (trend P=0.14). The association with the severe depressive state was more pronounced. By contrast, there was no such association in the workplace surveyed in July. Overall, this study did not provide evidence linking higher blood vitamin D levels with decreased depressive symptoms. The suggestive inverse association in sun-deprived season warrants further investigation.