Severity of obstructive sleep apnea and metabolic variables: complex relationship needs comprehensive consideration

摘要: Dear Editor: We recently read the article named ‘‘Correlation between severity of apnea and hypopnea sleep, hypertension serum lipid glycemic: a case control study’’ conducted by de Sousa Rodrigues Lira [1] with great interest. In this well-presented study, authors explored correlation obstructive sleep (OSA) levels blood pressure (BP), lipids glucose; however, no correlations OSA metabolic variables were found. First all, we congratulate for carrying out such an important study hypertension, dyslipidemia hyperglycemia. However, conclusion differs from previous studies focused on increased BP, profile, insulin resistance respiratory disturbance index [2–4]. This inconsistence may partly be explained small sample size in which should estimated through power calculations (a two-sided confidence level 99.9% 80%). 6–11 subjects per group not sufficient to draw conclusion. Besides, some additional considerations mentioned. First, physical activity dietary habits associated disorders patients [5], thus these factors considered. addition, confounding effects gender difference medications also have influence variables, taken into account. Finally, inflammatory cytokines (i.e., interleukins, tumor necrosis factor-a, C-reactive protein) adipokines leptin, adiponectin, visfatin resistin) are related obesity, [6]. These biomarkers altered conditions OSA. The results might more convincible if enroll participants give information about above-mentioned factors. believe that findings will provide valuable clarify comprehensive relationship