Relation between serum leptin levels, lipid profiles and neurocognitive deficits in Chinese OSAHS patients

The aim of this study was to compare serum leptin, apolipoprotein A1 (ApoA1), apolipoprotein J (ApoJ) and apolipoprotein H (ApoH) levels in males with obstructive sleep apnea and hypopnea syndrome (OSAHS) to those in healthy control subjects and to examine the possible relation between neurocognitive performance and these factors/serum markers in the subjects.

In this observational, cross-sectional study, a full-night polysomnography and sensitive neuropsychological assessment were performed on 50 newly diagnosed Chinese male patients and 30 healthy subjects. Fasting blood samples were used to measure leptin and ApoA1, ApoH and ApoJ levels using ELISA.

Compared with normal control subjects, OSAHS patients have significantly lower levels of ApoA1 and higher levels of leptin, ApoH and ApoJ. After adjustment for age, years of education, body mass index (BMI) and apnea-hypopnea index, leptin and ApoA1 were associated with global cognitive function, and leptin level was positively correlated with inhibition reaction time. ApoJ was negatively correlated with visual reproduction and logical memory performance. Multiple regression analysis shows that from age, BMI, education year, biomarker levels and the parameters of PSG, only the variables of leptin and education year added to the prediction of the Montreal cognitive assessment score in a statistically significant way.

Abnormal expression of leptin and apolipoproteins and poor performance on neuropsychological tests were observed in patients with OSAHS. There is also an association between serum leptin, ApoA1, and ApoJ levels and cognitive performance in the patients.