Body fat distribution, body composition, and respiratory function in elderly men.
BACKGROUND
Most population studies have reported weak or nonsignificant associations between body mass index (BMI; in kg/m2) and lung function.


OBJECTIVE
This study focused on the distinct effects of fat distribution and body composition on lung function and examined these relations in elderly men.


METHODS
The study was a cross-sectional evaluation of 2744 men aged 60-79 y who were free of cardiovascular disease and cancer and were drawn from general practices in 24 British towns. Anthropometric and body-composition [including fat mass (FM), fat-free mass (FFM), and percentage body fat (%BF) evaluated with bioelectric impedance] measurements were made, and lung function was examined by using spirometry.


RESULTS
Height-standardized forced expiratory volume in 1 s (FEV1) was diminished only in lean (BMI < 22.5) and obese (BMI > or = 30) men, but forced vital capacity (FVC) tended to decrease with increasing BMI (P < 0.01). All other measures of adiposity [ie, waist circumference (WC), waist-hip ratio (WHR), FM, and %BF] were significantly and inversely related to FEV1 and FVC after adjustment for confounders, including age and cigarette smoking (all: P < 0.05). This was seen both in nonobese (BMI < 30) and obese men. FFM was positively associated with FEV1 (P = 0.03) and to a lesser extent with FVC. Higher BMI and FFM were both associated with reduced odds of a low FEV1-FVC ratio (ie, <70%).


CONCLUSIONS
Total body fat and central adiposity are inversely associated with lung function, but increased FFM reflecting increases in muscle mass is associated with increased lung function and lower odds of low FEV1:FVC in the elderly.
Wannamethee
S Goya
SG
Department of Primary Care and Population Sciences, Royal Free and University College Medical School, London, United Kingdom. goya@pcps.ucl.ac.uk
Shaper
A Gerald
AG
Whincup
Peter H
PH
D000273:Adipose Tissue / Q000033:anatomy & histology* / Q000378:metabolism; D000368:Aged; D000375:Aging / Q000502:physiology; D001823:Body Composition / Q000502:physiology*; D050218:Body Fat Distribution; D015992:Body Mass Index; D002318:Cardiovascular Diseases / Q000453:epidemiology; D003430:Cross-Sectional Studies; D017097:Electric Impedance; D005500:Follow-Up Studies; D005541:Forced Expiratory Volume; D006801:Humans; D008168:Lung / Q000502:physiology*; D008297:Male; D008450:Maximal Midexpiratory Flow Rate; D008875:Middle Aged; D018482:Muscle, Skeletal / Q000378:metabolism; D009765:Obesity / Q000378:metabolism / Q000503:physiopathology*; D010101:Oxygen Consumption; D011446:Prospective Studies; D012129:Respiratory Function Tests; D012307:Risk Factors; D013147:Spirometry; D014797:Vital Capacity; D049629:Waist-Hip Ratio