Biomedical subjects

Lewis J Smith

Publications and source records attributed to Lewis J Smith.

3 recordsLinked to original sources

PubMed2006

Plasma fibrinogen and lung function: the CARDIA Study.

BACKGROUND: We hypothesized that fibrinogen, as a marker of chronic inflammation, is inversely associated with forced vital capacity (FVC) and forced expiratory volume in 1 s (FEV(1)) in healthy persons. METHODS: The CARDIA cohort started in 1985 and included black and white men and women, aged 18-30, from the general population. Spirometry testing conducted at years 5 and 10 [FVC, FEV(1), and their ratio (FEV(1)/FVC)] was studied relative to plasma fibrinogen levels measured at year 5 (cross-sectional n = 4,040) and at year 7 (longitudinal n = 3,001), controlling for race, sex, age, height, smoking, asthma, body mass index, physical activity, birth control pill use, and alcohol intake. RESULTS: In cross-sectional analyses, FVC at year 5 was lower by 166 ml (95% confidence interval 116-216 ml) in the highest vs lowest year 5 fibrinogen quartile. At year 10, holding year 5 FVC and change in fibrinogen (year 7-year 5) constant, the difference in FVC between the highest and the lowest year 5 fibrinogen quartiles widened by 67 ml (95% CI 31-103 ml). The corresponding differences for FEV(1) were 166 ml (95% CI 146-253 ml) at year 5 and 45 ml (95% CI 11-80 ml) widening by year 10. The FEV(1)/FVC ratio was unrelated to plasma fibrinogen. CONCLUSION: These findings are consistent with the hypothesis that fibrinogen, possibly as a marker for chronic low-grade inflammation, is associated with modest deterioration of lung function in healthy young adults.

Adolescent↗

PubMed2006

Effect of obesity on clinical presentation and response to treatment in asthma.

Obesity is a risk factor for being diagnosed with asthma, but there is conflicting evidence on whether obesity is a risk factor for lung function abnormalities characteristic of asthma. We studied a cohort of 488 subjects, 47% of whom were obese. Obese and non-obese subjects with asthma had similar airflow limitation and bronchodilator responsiveness, but obese participants had increased sleep disturbance and gastroesophageal reflux disease, higher cytokine levels, and a trend towards increased exacerbations when treated with theophylline. Obese and non-obese asthmatics have similar lung function abnormalities, but comorbidities and altered responses to medications may significantly affect asthma control in obese people.

Acetates↗

PubMed2004

Dietary intake of soy genistein is associated with lung function in patients with asthma.

To determine if micronutrient intake is associated with asthma severity, we administered the Block food frequency questionnaire to participants in a randomized clinical trial of the safety of influenza vaccine for asthmatics. The nutrition substudy included 1033 participants, aged 12-75. Intake of antioxidant vitamins, soy isoflavones, total fruits and vegetables, fats, and fiber was compared with asthma severity at baseline [forced expiratory volume in 1 second (FEV1), peak expiratory flow rate (PEF), asthma symptoms] and the rate of asthma exacerbations during the 2 weeks following influenza vaccination. The only nutrient that had a consistent association with asthma severity was genistein, a soy isoflavone. None of the nutrients evaluated were related to asthma exacerbation rate when adjusted for known confounders. The FEV1 in genistein consumers of at least 250 microg/1000 Kcal/day was 82.1% predicted, 79.9% predicted for those who consumed between 1 and 249 microg/1000 kcal, and 76.2% predicted in genistein nonconsumers (p=0.006); the PEF was 82.7% predicted, 80.8% predicted, and 78.3% predicted, respectively (p=0.009). There were no differences in the Asthma Symptom Utility Index (ASUI). We could not account for these results based on differences in demographics, body mass index, or consumption of other nutrients. Thus, increasing consumption of genistein is associated with better lung function in patients with asthma. Further studies are needed to determine whether dietary supplementation with genistein can reduce asthma severity.

Adolescent↗