Slowing gait speed precedes cognitive decline by several years

INTRODUCTION: In this longitudinal study, we aimed to examine if slowing gait speed preceded cognitive decline and correlated with brain amyloidosis. METHODS: The sample (n = 287) was derived from the Gothenburg H70 Birth Cohort Studies, with follow-ups between 2000 and 2015. Gait speed was measured by indoor walk, and cognition using the Clinical Dementia Rating (CDR) score. All participants had CDR = 0 at baseline. Some participants had data on cerebrospinal fluid (CSF) amyloid beta (Aβ)1-42 concentrations at the 2009 examination. RESULTS: Gait speed for participants who worsened in CDR score during follow-up was slower at most examinations. Baseline gait speed could significantly predict CDR change from baseline to follow-up. Subjects with pathological CSF Aβ1- 42 concentrations at the 2009 visit had lost more gait speed compared to previous examinations. DISCUSSION: Our results indicate that gait speed decline precedes cognitive decline, is linked to Alzheimer's pathology, and might be used for early detection of increased risk for dementia development

Results from Ward hierarchical cluster analysis based on Spearman correlation.

<p>The analysis resulted in five clusters: the <i>Hop performance and knee strength</i> cluster is associated with absolute measurements of functional tests and knee strength measures; the <i>Perceived knee function</i> cluster is linked with scores and questionnaires; the <i>Knee function reflected in activity and health cluster</i> contains a mixture of variables of different character; the <i>Knee strength ratio</i> and the <i>Limb asymmetry</i> clusters were mainly associated with relative measurements between legs (LSI) in functional tests.</p

Distributions of the estimator of knee function and the test battery variables.

<p>The distribution of each of the variables included in the estimator of knee function (w) for each of the two groups, <i>i</i>.<i>e</i>. individuals with an ACL injury and healthy-knee controls. For the estimator of knee function, values close to 1 indicate a good knee function, and values close to 0 indicate the opposite. Quadriceps concentric strength was measured in Nm/kg; the one-leg hop for distance in meters, the one-leg balance in number of floor support, and the side hop in number of side hops.</p

Misclassification rates for different sizes of test batteries.

<p>Misclassification rates for about 72 000 test batteries of different sizes, representing different combinations of the included test variables. The size of the test battery is the number of included variables. The misclassification rate should be as low as possible. The results for combinations consisting of 5, 10, 15 and 20 variables are based on 10000 random samples. The horizontal line indicates our threshold (0.2) for the highest acceptable misclassification rate.</p

Illustration of the data structure and the statistical approach.

<p>First, correlation analysis combined with cluster analysis is applied to better understand the relationship between all outcome variables. Potential test batteries are then investigated using logistic regression and subsequently evaluated based on their misclassification rate and on their feasibility. The combined outcomes of the final test battery result in an estimator of knee function, again using logistic regression. Finally, this new variable (estimator of knee function) is analyzed using traditional statistical approaches such as Spearman rank correlation and Wilcoxon rank sum test.</p

Misclassification rates and the T:E-index for a selected subset of test batteries.

<p>Misclassification rates and the T:E-index for a selected subset of test batteries.</p

Participant characteristics.

<p>Participant characteristics.</p

A brief description of the 48 outcome variables included in the analysis.

<p>A brief description of the 48 outcome variables included in the analysis.</p

Six-year mortality associated with living alone and loneliness in Swedish men and women born in 1930

Abstract Background This study examined how living alone and loneliness associate with all-cause mortality in older men and women. Methods Baseline data from the Gothenburg H70 Birth Cohort Studies, including 70-year-olds interviewed in 2000 and 75-year-olds (new recruits) interviewed in 2005 were used for analyses (N = 778, 353 men, 425 women). Six-year mortality was based on national register data. Results At baseline, 36.6% lived alone and 31.9% reported feelings of loneliness. A total of 72 (9.3%) participants died during the 6-year follow-up period. Cumulative mortality rates per 1000 person-years were 23.9 for men and 9.6 for women. Mortality was increased more than twofold among men who lived alone compared to men living with someone (HR 2.40, 95% CI 1.34–4.30). Elevated risk remained after multivariable adjustment including loneliness and depression (HR 2.56, 95% CI 1.27–5.16). Stratification revealed that mortality risk in the group of men who lived alone and felt lonely was twice that of their peers who lived with someone and did not experience loneliness (HR 2.52, 95% CI 1.26–5.05). In women, a more than fourfold increased risk of mortality was observed in those who experienced loneliness despite living with others (HR 4.52, 95% CI 1.43–14.23). Conclusions Living alone was an independent risk factor for death in men but not in women. Mortality was doubled in men who lived alone and felt lonely. In contrast, mortality was particularly elevated in women who felt lonely despite living with others. In the multivariable adjusted models these associations were attenuated and were no longer significant after adjusting for mainly depression in men and physical inactivity in women. Gender needs to be taken into account when considering the health consequences of living situation and loneliness