Pulmonary function, cognitive impairment and brain atrophy in a middle-aged community sample.
OBJECTIVE
To determine the relationship of lung function to brain anatomical parameters and cognitive function and to examine the mediating factors for any relationships.


METHODS
A random sub-sample of 469 persons (men = 252) aged 60-64 years from a larger community sample underwent brain magnetic resonance imaging scans and pulmonary function tests (forced vital capacity, FVC, forced expiratory volume in the first second, FEV(1)). Subjects were assessed for global cognitive function, episodic memory, working memory, information processing speed, fine motor dexterity and grip strength. The magnetic resonance imaging scans were analysed for overall brain atrophy, subcortical atrophy (ventricle-to-brain ratio, VBR), hippocampal volume, and white matter hyperintensity (WMH) volume.


RESULTS
FEV(1) had a significant negative correlation with overall brain atrophy and VBR in men. The FEV(1)/FVC ratio had a significant correlation with WMHs in both men and women. In regression models that controlled for sex, age, height, level of activity, smoking, chronic respiratory disease and education, FEV(1) and FVC were significant predictors of VBR but no other structural brain measure. Pulmonary function was also significantly related to information processing speed and fine motor dexterity. Male subjects with chronic respiratory disease had more deep WMHs. Path analyses to examine if structural measures mediated between lung function and cognition, and whether markers of inflammation and oxidative stress or cortisol mediated between lung function and brain measures were negative.


CONCLUSIONS
Decreased lung function is related to poorer cognitive function and increased subcortical atrophy in mid-adult life. Presence of chronic respiratory disease may be related to deep WMHs in men.
School of Psychiatry, University of New South Wales, Sydney, Australia. p.sachdev@unsw.edu.au
P S
PS
Sachdev
K J
KJ
Anstey
R A
RA
Parslow
W
W
Wen
J
J
Maller
R
R
Kumar
H
H
Christensen
A F
AF
Jorm
D001284:Atrophy / Q000473:pathology; D001921:Brain / Q000033:anatomy & histology / Q000473:pathology*; D002097:C-Reactive Protein / Q000502:physiology; D003072:Cognition Disorders / Q000175:diagnosis* / Q000453:epidemiology / Q000209:etiology*; D003430:Cross-Sectional Studies; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008171:Lung Diseases / Q000175:diagnosis / Q000453:epidemiology* / Q000503:physiopathology*; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009483:Neuropsychological Tests; D015995:Prevalence; D012129:Respiratory Function Tests; D012720:Severity of Illness Index
D002097:C-Reactive Protein