Chest
Clinical InvestigationsOBESITYExpiratory Flow Limitation and Orthopnea in Massively Obese Subjects
Section snippets
Subjects
Forty-six obese subjects (18 men) with a mean body mass index (BMI) of > 40 kg/m2 were investigated in a prospective open study at the respiratory division of Sant'Orsola-Malpighi Hospital in Bologna, Italy. The mean (± SD) age and BMI were 42 ± 11 years and 50 ± 8 kg/m2, respectively, for men and 45 ± 10 years and 51 ± 9 kg/m2, respectively, for women. Five men and eight women were current smokers, while four men and five women were previous smokers. None of the subjects had acute or chronic
Results
The anthropometric characteristics and lung function parameters of the subjects are given in Table 1. According to the MRC dyspnea scale, the chronic dyspnea score as reported by our subjects was mild, amounting to 1.1 ± 0.1. Twenty-one subjects (14 men) had OSAHS, with a markedly higher prevalence in men (78%) than in women (25%).
None of the subjects exhibited complete EFL in either position. Partial EFL was detected in 10 subjects (4 men) when seated, and in 27 subjects (10 men) when supine,
Discussion
The main findings of this study of healthy, massively obese subjects are the following: (1) partial EFL is common when subjects are supine, while it is seldom observed when they are seated; (2) almost half of these subjects experienced orthopnea, although to a mild degree; and (3) in most subjects orthopnea was associated with the occurrence or worsening of EFL in the supine position.
Before discussing these results, some aspects inherent in the NEP method chosen to detect EFL need to be
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