The impact of metabolic syndrome on ventilatory pulmonary Functions

Abstract

Abstract Background A relationship between metabolic syndrome (MS) and lung disease has been observed in several cross-sectional and longitudinal studies. This syndrome has been identified as an independent risk factor for worsening respiratory symptoms and higher lung function impairment. Aim The aim of this study was to analyze the effect of MS on ventilatory pulmonary functions. Patients and methods This study included 60 participants. They were divided to two groups – group A included 45 patients with MS, and group B included 15 apparently healthy participants as a control group. All of them were subjected to the following: complete history taking and physical examination (blood pressure, BMI, and waist circumference), laboratory investigations for fasting blood glucose, lipid profile (triglyceride and high-density lipoprotein), C-reactive protein, and HbA1C, and spirometry [forced vital capacity (FVC), forced expiratory volume in first second (FEV1), and FEV1/FVC]. Results Among MS participants (n=45), 28 (63%) had the restrictive ventilatory pattern, three (6%) had the obstructive pattern, nine (20%) were normal, and five (11%) had a mixed pattern. Pulmonary functions were impaired more among MS cases. FVC% predicted of group A was 61.49±17.56%, whereas in group B it was 85.73±5.24%. FEV1% predicted of group A was 66.22±18.7%, whereas in group B it was 87.73 ±7.98%. The differences were statistically highly significant. Pulmonary function impairment was more prominent among males than among females. After examining the association between metabolic components and both FVC% predicted and FEV1% predicted, the results revealed that there was a strong linear decrease in FVC% predicted and FEV1% predicted as the number of components of MS increased. The β coefficients of FVC% predicted for those with 1, 2, 3, 4, and 5 features of MS were 0.011, −0.018, −0.023, −0.035, and −0.048 in men and 0.020, −0.029, −0.035, −0.047, and −0.068 in women, respectively. The β coefficients of FEV1% predicted for those with 1, 2, 3, 4, and 5 features of MS were 0.009, −0.015, −0.026, −0.041, and −0.051 in men and 0.004, −0.009, −0.017, −0.029, and −0.038 in women, respectively. Conclusion Pulmonary function impairment (mainly restrictive pattern) is commonly associated with MS. FVC and FEV1 are inversely associated with the accumulation of elements of MS and also associated independently with each element of MS, especially waist circumference.

Keywords

• forced expiratory volume in the first second
• forced vital capacity
• metabolic syndrome
• spirometry
• waist circumference