BACKGROUND: This cohort study aimed to identify the accumulation patterns of objectively measured ambulatory activity (AA) variables in the middle-aged and older Japanese women and examine the relationship of these derivative patterns with onset of metabolic syndrome (MetS). METHODS: A total of 794 women (mean age: 56.2 years) provided objectively assessed AA data using a uniaxial accelerometer. The number of steps, time accumulated in light-intensity AA (LIAA) and moderate-to-vigorous intensity AA (MVAA) and the ratio of MVAA to total AA (LIAA + MVAA) were calculated. Latent profile analysis was used to identify participant groups based on their distinct AA patterns. Logistic regression models were used to assess the association of groups with the onset of MetS after adjusting for age, sex, education, alcohol habit, smoking habit, energy intake, and the number of MetS components present at baseline. RESULTS: Four distinct groups were identified: Group A had low levels of the AA variable; group B accumulated a certain number or more steps primarily through MVAA; group C accumulated a certain number or more steps primarily through LIAA; and group D had high level of the AA variables. Over the course of the 5-year follow-up period, 61 participants (7.7%) developed MetS. The multivariate-adjusted odds ratio (95% confidence interval) for onset of MetS in groups B, C, and D relative to group A were 0.416 (0.166-1.218), 0.451 (0.223-0.914), and 0.933 (0.365-2.382), respectively. Group C had a significantly lower odds ratio of MetS onset than group A. CONCLUSION AA patterns accumulating a certain number or more steps, regardless of the intensity of AA, may help reduce the risk of MetS compared to inactive AA patterns.
Humans ; Metabolic Syndrome/etiology* ; Female ; Middle Aged ; Japan/epidemiology* ; Aged ; Exercise ; Cohort Studies ; Accelerometry ; Risk Factors ; East Asian People

Objectives: Few studies examined the association between deterioration of masticatory ability assessed by objective marker and physical function. Therefore, we examined the association between salivary flow rate which is one of the objective and surrogate marker of masticatory ability and lower Timed Up & Go (TUG) performance which is one of major measurement of physical function among aging Japanese. Methods: This cross-sectional study enrolled 464 Japanese aged 60e84 years old. Participants chewed tasteless and odorless gum for 5 min, calculated stimulated salivary flow rate (g/min) during all chews.The 3 m TUG was conducted, and 75th percentile value (6.8 s for men and 7.0 s for women) or higher was defined as lower TUG performance. Logistic regression analysis was used to examine the association between stimulated salivary flow rate and lower TUG performance. Results: We found that the stimulated salivary flow rate tended to be negatively associated with the TUG time. We also observed significant negative association between stimulated salivary flow rate and lower TUG performance; the multivariable-adjusted OR (95% confidence interval, CIs) of lower TUG performance for the highest quartile of stimulated salivary flow rate compared with the lowest quartile was0.34 (0.16e0.69, P for trend ¼ 0.02). Further adjusting for BMI, the association was attenuated but remaind significant; the OR (95% CIs) in highest quartile was 0.37 (0.18e0.76, P for trend ¼ 0.04). Conclusions Higher stimulated salivary flow, which means well masticatory ability, was inversely associated with lower TUG performance in the aging Japanese population.