ABSTRACT
The incidence of asthma and obesity is increasing worldwide. Understanding the causal directions between asthma and obesity could have important therapeutic implications. However, the mechanism connecting the two is not well defined. This study was undertaken to compare pulmonary function tests [PFTs], C-reactive protein [CRP] and inflammatory cytokines in obesity and asthma in Egyptian adolescents and to investigate whether obese asthmatics have a specific inflammatory phenotype than lean asthmatics. Fifty asthmatic and 30 control subjects were enrolled in the study and divided into 2 sub-groups: obese and non-obese. Serum levels of CRP, leptin, tumor necrosis factor-alpha [TNF-alpha], interleukin-6 [IL-6], IL-5, body mass index [BMI] and PFTs were done for asthmatics and controls. Serum levels of IL-6, TNF-alpha and leptin in obese individuals whether asthmatic or not showed significant increase compared to lean ones [P < 0.01]. Body mass index [BMI] showed positive linear correlations with serum levels of IL-6, TNF-alpha, leptin and CRP. Serum IL-5 showed significantly higher levels in all asthmatics versus all controls [P < 0.01]. Also serum IL-5 showed non-significant difference between lean and obese asthmatics and it showed significant negative correlations with FEVl/FVC% and PEF. Serum levels oflL-6, TNF-alpha and leptin could be considered surrogate markers for obesity, whereas serum IL-5 is considered a marker of airway inflammation in bronchial asthma. Thus obesity and asthma have been shown to coexist together but systemic and airway inflammation appears to operate independent of each other
ABSTRACT
The aim of the work was to study the involvement of the optic tract in both conditions by measuring the latency and amplitude of the visual evoked potentials in those patients. Subjects and Twenty patients and 10 controls were studied. Ten patients had recently diagnosed Graves' disease and 10 had recently diagnosed primary hypothyroidism. Detailed ophthalmologic assessment was performed. Pattern VEP was recorded for all subjects, each eye separately. P100 latency and amplitude were used for comparing patients and controls. Thyroid hormone levels and thyroid stimulating hormone were measured. Patients with Graves' disease had abnormally prolonged latency [P100 = 109 +/- 20 msec] as compared to controls [94 +/- 6 msec]; P < 0.05. They also had significantly lower PI00 amplitude [3.2 +/- 2.6 vs. 5.9 +/- 2.7 mV; P < 0.05]. Those with abnormal VEP [4/10 patients] had significantly higher degree of proptosis but normal visual acuity and intraocular pressure. P100 latency correlated positively with the level of T3 [r=0.79]. Patients with primary hypothyroidism had abnormally prolonged P100 latency [112 +/- 24 msec, P < 0.05. In hypothyroid patients with prolonged latency [5/10 patients], P100 correlated significantly with age [r=0.6], duration of symptoms [r=0.66] and intraocular pressure [r=0.87]. Conclusions: VEP is more sensitive as regards the detection of pre-clinical visual pathway abnormality in patients with Graves' disease than fundus or visual field examination, where prolonged latency of P100 in VEP indicates pre-clinical optic nerve involvement. In patients with hypothyroidism, prolonged latency of VEP was present in 50% of the studied cases, thus the CNS is more sensitive to thyroid hormone deficiency than to excess. Further study is needed to determine its value as a quantitative test for CNS involvement in hypothyroidism