@article {6285, title = {Bidirectional relationship between cognitive function and pneumonia.}, journal = {Am J Respir Crit Care Med}, volume = {188}, year = {2013}, month = {2013 Sep 01}, pages = {586-92}, abstract = {

RATIONALE: Relationships between chronic health conditions and acute infections remain poorly understood. Preclinical studies suggest crosstalk between nervous and immune systems.

OBJECTIVES: To determine bidirectional relationships between cognition and pneumonia.

METHODS: We conducted longitudinal analyses of a population-based cohort over 10 years. We determined whether changes in cognition increase risk of pneumonia hospitalization by trajectory analyses and joint modeling. We then determined whether pneumonia hospitalization increased risk of subsequent dementia using a Cox model with pneumonia as a time-varying covariate.

MEASUREMENTS AND MAIN RESULTS: Of the 5,888 participants, 639 (10.9\%) were hospitalized with pneumonia at least once. Most participants had normal cognition before pneumonia. Three cognition trajectories were identified: no, minimal, and severe rapid decline. A greater proportion of participants hospitalized with pneumonia were on trajectories of minimal or severe decline before occurrence of pneumonia compared with those never hospitalized with pneumonia (proportion with no, minimal, and severe decline were 67.1\%, 22.8\%, and 10.0\% vs. 76.0\%, 19.3\%, and 4.6\% for participants with and without pneumonia, respectively; P < 0.001). Small subclinical changes in cognition increased risk of pneumonia, even in those with normal cognition and physical function before pneumonia (β = -0.02; P < 0.001). Participants with pneumonia were subsequently at an increased risk of dementia (hazard ratio, 2.24 [95\% confidence interval, 1.62-3.11]; P = 0.01). Associations were independent of demographics, health behaviors, other chronic conditions, and physical function. Bidirectional relationship did not vary based on severity of disease, and similar associations were noted for those with severe sepsis and other infections.

CONCLUSIONS: A bidirectional relationship exists between pneumonia and cognition and may explain how a single episode of infection in well-appearing older individuals accelerates decline in chronic health conditions and loss of functional independence.

}, keywords = {Aged, Cognition Disorders, Dementia, Female, Hospitalization, Humans, Longitudinal Studies, Male, Neuropsychological Tests, Pneumonia, Proportional Hazards Models, Risk Factors}, issn = {1535-4970}, doi = {10.1164/rccm.201212-2154OC}, author = {Shah, Faraaz Ali and Pike, Francis and Alvarez, Karina and Angus, Derek and Newman, Anne B and Lopez, Oscar and Tate, Judith and Kapur, Vishesh and Wilsdon, Anthony and Krishnan, Jerry A and Hansel, Nadia and Au, David and Avdalovic, Mark and Fan, Vincent S and Barr, R Graham and Yende, Sachin} } @article {5997, title = {Effects of respiratory and non-respiratory factors on disability among older adults with airway obstruction: the Cardiovascular Health Study.}, journal = {COPD}, volume = {10}, year = {2013}, month = {2013 Oct}, pages = {588-96}, abstract = {

BACKGROUND: High rates of disability associated with chronic airway obstruction may be caused by impaired pulmonary function, pulmonary symptoms, other chronic diseases, or systemic inflammation.

METHODS: We analyzed data from the Cardiovascular Health Study, a longitudinal cohort of 5888 older adults. Categories of lung function (normal; restricted; borderline, mild-moderate, and severe obstruction) were delineated by baseline spirometry (without bronchodilator). Disability-free years were calculated as total years alive and without self-report of difficulty performing \&γτ;1 Instrumental Activities of Daily Living over 6 years of follow-up. Using linear regression, we compared disability-free years by lung disease category, adjusting for demographic factors, body mass index, smoking, cognition, and other chronic co-morbidities. Among participants with airflow obstruction, we examined the association of respiratory factors (FEV1 and dyspnea) and non-respiratory factors (ischemic heart disease, congestive heart failure, diabetes, muscle weakness, osteoporosis, depression and cognitive impairment) on disability-free years.

RESULTS: The average disability free years were 4.0 out of a possible 6 years. Severe obstruction was associated with 1 fewer disability-free year compared to normal spirometry in the adjusted model. For the 1,048 participants with airway obstruction, both respiratory factors (FEV1 and dyspnea) and non-respiratory factors (heart disease, coronary artery disease, diabetes, depression, osteoporosis, cognitive function, and weakness) were associated with decreased disability-free years.

CONCLUSIONS: Severe obstruction is associated with greater disability compared to patients with normal spirometery. Both respiratory and non-respiratory factors contribute to disability in older adults with abnormal spirometry.

}, keywords = {Activities of Daily Living, Aged, Cognition Disorders, Cohort Studies, Comorbidity, Depression, Diabetes Mellitus, Disease Progression, Dyspnea, Female, Heart Failure, Humans, Linear Models, Longitudinal Studies, Male, Muscle Weakness, Myocardial Ischemia, Osteoporosis, Pulmonary Disease, Chronic Obstructive, Severity of Illness Index, Spirometry}, issn = {1541-2563}, doi = {10.3109/15412555.2013.781148}, author = {Locke, Emily and Thielke, Stephen and Diehr, Paula and Wilsdon, Anthony G and Barr, R Graham and Hansel, Nadia and Kapur, Vishesh K and Krishnan, Jerry and Enright, Paul and Heckbert, Susan R and Kronmal, Richard A and Fan, Vincent S} }