Tomohiko Kamo1, Ryoma Asahi2, Masato Azami2, Hirofumi Ogihara2, Tomoko Ikeda3, Keisuke Suzuki4, Yuusuke Nishida5. 1. Department of Physical Therapy, School of Health Sciences, Japan University of Health Sciences, 2-555, Hirasuka, Satte-city, Saitama, 340-0145 Japan. Electronic address: t-kamo@jhsu.ac.jp. 2. Department of Physical Therapy, School of Health Sciences, Japan University of Health Sciences, 2-555, Hirasuka, Satte-city, Saitama, 340-0145 Japan. 3. Department of Nursing, School of Health Sciences, Japan University of Health Sciences, 1961-2, Satte, Satte-city, Saitama, 340-0113 Japan. 4. Department of Physical Therapy, School of Health Sciences at Odawara, International University of Health and Welfare, 1-2-25, Shiroyama, Odawara-city, Kanagawa, 250-8588 Japan. 5. Department of Physical Therapy, School of Health Sciences at Narita, International University of Health and Welfare, 4-3, Kōzunomori, Narita-shi, Chiba-ken, 286-8686 Japan.
Abstract
BACKGROUND: Rate of torque development (RTD) is defined as the slope of the torque-time curve obtained during an isometric contraction. Several studies have shown that RTD is lower in fallers than in nonfallers. However, these studies had small sample size and was not adjusted confounding factors. RESEARCH QUESTION: Is RTD associated with falls history in healthy community dwelling older adults. METHODS: This was cross-sectional study. In total, 122 participants aged ≥65 (mean, 71.3 ± 4.4) years were recruited for this study. We assessed RTD, muscle strength, functional capacity, and physical activity. We assessed RTD over the first 200 ms of the maximal isometric contraction, whereby the onset of contraction was deemed as the point at which torque had risen 4 Nm above the baseline. Differences between the 3 groups (no fall group, single fall group and multiple falls group) were examined using one-way analysis of variance or Kruskal-Wallis test. A post-hoc Bonferroni or Games-Howell test was used to assess the differences between the individual groups. A multivariate multinomial logistic model was built using the factors associated with the fall category. RESULTS: RTD was significantly different between the no fall group and multiple falls group (P = 0.047). Similarly, RTD was significantly different between the single fall group and multiple falls group (P = 0.016). RTD was associated with both the no fall group and single fall group (odds ratio = 2.05, 95% confidence interval: 1.06-3.97, odds ratio = 2.45, 95% confidence interval: 1.20-4.98, respectively) in multinomial logistic regression. SIGNIFICANCE: This is the first study to investigate the relationship between RTD and falls history in community-dwelling older adults in multivariate analysis. RTD is more strongly associated with falls history than other performance measures in community-dwelling elderly.
BACKGROUND: Rate of torque development (RTD) is defined as the slope of the torque-time curve obtained during an isometric contraction. Several studies have shown that RTD is lower in fallers than in nonfallers. However, these studies had small sample size and was not adjusted confounding factors. RESEARCH QUESTION: Is RTD associated with falls history in healthy community dwelling older adults. METHODS: This was cross-sectional study. In total, 122 participants aged ≥65 (mean, 71.3 ± 4.4) years were recruited for this study. We assessed RTD, muscle strength, functional capacity, and physical activity. We assessed RTD over the first 200 ms of the maximal isometric contraction, whereby the onset of contraction was deemed as the point at which torque had risen 4 Nm above the baseline. Differences between the 3 groups (no fall group, single fall group and multiple falls group) were examined using one-way analysis of variance or Kruskal-Wallis test. A post-hoc Bonferroni or Games-Howell test was used to assess the differences between the individual groups. A multivariate multinomial logistic model was built using the factors associated with the fall category. RESULTS:RTD was significantly different between the no fall group and multiple falls group (P = 0.047). Similarly, RTD was significantly different between the single fall group and multiple falls group (P = 0.016). RTD was associated with both the no fall group and single fall group (odds ratio = 2.05, 95% confidence interval: 1.06-3.97, odds ratio = 2.45, 95% confidence interval: 1.20-4.98, respectively) in multinomial logistic regression. SIGNIFICANCE: This is the first study to investigate the relationship between RTD and falls history in community-dwelling older adults in multivariate analysis. RTD is more strongly associated with falls history than other performance measures in community-dwelling elderly.