[A literature review on the relationship between questionnaires for assessing minor health complaints and health status indices among Japanese people].

Objectives　Minor health complaints related to stress, mental health, sleep, and fatigue are closely associated with each other, and their deterioration may cause lifestyle diseases. The health status of people can be predicted through a questionnaire by exploring the relationship between their state of minor health complaints and objective health status indices. Therefore, we conducted a systematic review of the relationship between a questionnaire on the state of minor health complaints and health status indices among Japanese people who have a high level of stress, which they experience on a daily basis, using epidemiological literature. Additionally, we considered items for the questionnaire which were necessary for an index development.Methods　The PubMed database was searched for papers on "autonomic nervous system," "sleep disorders," "mental health and stress," and "fatigue," using keywords mentioned in previous studies on minor health complaints.　The extracted research papers were screened according to the following inclusion criteria: 1) the participants were healthy Japanese people; 2) descriptions included characteristics of the target population; 3) use of analytic epidemiological study design, intervention studies, and systematic reviews; 4) minor health complaints assessed by a questionnaire; 5) evaluation of the relationship between the questionnaires for minor health complaints and the health index; and 6) written in Japanese or English. Based on this, ten papers were adopted.Results　Of the 10 papers collected, one was a cohort study, three were case-control studies, and six were cross-sectional studies. The participants in five of them were working adults. Reports on three out of six questionnaires on stress, four out of seven on sleep, and all two on comprehensive health status showed significant associations between minor health complaints assessed by the questionnaires and the index for health status. The increase in responses about work-related stress from the questionnaire was associated with an increase in the "risk of developing depression" [odds ratio 2.96 (confidence interval: 1.04-8.42)]. Poor sleep quality was associated with an increase in "changes in autonomic index," "number of comorbidities and the rate of depression," and the "risk of work-related injuries." Moreover, the health score was associated with the "autonomic nervous system index".Conclusion　These results suggest that a questionnaire evaluating minor health complaints should include questions about "stress," "sleep quality," and "comprehensive health status." Since studies that appropriately adopted for risk of bias were limited, it is necessary to further examine these relationships by applying prospective studies such as cohort studies and intervention studies.

Low-dose vitamin K2 (MK-4) supplementation for 12 months improves bone metabolism and prevents forearm bone loss in postmenopausal Japanese women.

Menaquinone-4 (MK-4) administered at a pharmacological dosage of 45 mg/day has been used for the treatment of osteoporosis in Japan. However, it is not known whether a lower dose of MK-4 supplementation is beneficial for bone health in healthy postmenopausal women. The aim of this study was to examine the long-term effects of 1.5-mg daily supplementation of MK-4 on the various markers of bone turnover and bone mineral density (BMD). The study was performed as a randomized, double-blind, placebo-controlled trial. The participants (aged 50-65 years) were randomly assigned to one of two groups according to the MK-4 dose received: the placebo-control group (n = 24) and the 1.5-mg MK-4 group (n = 24). The baseline concentrations of undercarboxylated osteocalcin (ucOC) were high in both groups (>5.1 ng/ml). After 6 and 12 months, the serum ucOC concentrations were significantly lower in the MK-4 group than in the control group. In the control group, there was no significant change in serum pentosidine concentrations. However, in the MK-4 group, the concentration of pentosidine at 6 and 12 months was significantly lower than that at baseline. The forearm BMD was significantly lower after 12 months than at 6 months in the control group. However, there was no significant decrease in BMD in the MK-4 group during the study period. These results suggest that low-dose MK-4 supplementation for 6-12 months improved bone quality in the postmenopausal Japanese women by decreasing the serum ucOC and pentosidine concentrations, without any substantial adverse effects.

[Preservation of quality of life and its relation to lifestyle in centenarians in Japan: a visitation interview survey].

PURPOSE: To investigate quality of life (QOL) and associated factors in centenarians, we conducted a visitation interview survey for all male and one half of the female centenarians living in Japan, and studied QOL, lifestyle and health status. METHODS: All the male centenarians and a randomly-sampled half of the female centenarians living in Japan were included in the study based on the National Census. Finally, 556 male and 1341 female centenarians participated in the present visitation interview survey and were studied using a structured questionnaire. QOL was assessed from 3 aspects; activities of daily life (ADL), cognitive function (CF) and mental health (MH). RESULTS: Individuals having superior ADL accounted for 30.9% of the male and 13.6% of the female centenarians, those with superior CF were 58.1% and 35.6%, respectively, and those with superior MH were 39.2% and 26.8%, providing evidence that superior QOL was more dominant in males than in females. There were no effects of residential areas (north, east, middle, west, southwest and south of Japan) on the prevalence of ADL, CF and MH. Multiple logistic regression analyses conducted independently, for ADL, CF and MH as dependent valuables revealed that habitual exercise, less decline in visual ability and preservation of masticating ability were associated with better results for these 3 aspects of male centenarians' QOL, and that habitual exercise, less decline in visual ability, spontaneous awakening in the morning, good appetite and having cohabitating family members were associated with superior QOL in the females, suggesting that more factors are operating in the latter. CONCLUSIONS: Several lifestyle factors were found to be associated with preservation of QOL in centenarians in Japan. These results should facilitate establishing a public health and welfare policy for the most senior citizens, a group that has been increasing in Japan.

Effect of low dose vitamin K2 (MK-4) supplementation on bio-indices in postmenopausal Japanese women.

It has been reported that treatment with a pharmacological dose (45 mg/d) of menaquinone-4 (MK-4) prevents bone loss in postmenopausal women. However, it is not known whether supplementation with low dose MK-4 has beneficial effects on bone metabolism in healthy women. The aim of this study is to examine the effects of the supplementation of 1.5 mg/d MK-4 for 4 wk on bone and lipid metabolism in healthy postmenopausal Japanese women. The study was performed as a randomized double blind placebo-controlled trial. The participants aged 53-65 y were randomly assigned to 2 groups and supplemented with 1.5 mg/d of MK-4 or a placebo for 4 wk (n=20 for each group). The most marked effects of MK-4 intake were observed on serum osteocalcin (OC) concentrations. Serum undercarboxylated OC (ucOC) concentration decreased, and the gamma-carboxylated OC (GlaOC) and GlaOC/GlaOC+ucOC ratio that indicates the degree of OC gamma-carboxylation increased significantly at 2 and 4 wk compared with that at baseline in the MK-4 group. The serum ucOC and GlaOC concentrations in the MK-4 group were significantly different from those in the placebo group at 2 wk. These results suggest that supplementation with 1.5 mg/d MK-4 accelerated the degree of OC gamma-carboxylation. The concentrations of serum lipids and other indices were not different between the groups at either intervention period. Thus, the additional intake of MK-4 might be beneficial in the maintenance of bone health in postmenopausal Japanese women.