High-Density Lipoprotein and Verbal Learning in First Episode Psychosis

For patients with first episode psychosis being treated with antipsychotic medication, an increase in high-density lipoprotein (HDL) cholesterol was associated with better verbal learning at a 1-year follow-up, according to a study published in the European Archives of Psychiatry and Clinical Neuroscience.

Researchers evaluated participants from the Thematically Organized Psychosis study to identify the association between cognition, serum lipid levels, and the effect lifestyles, metabolic measurements, improvements in symptoms, and other illness-related factors might have on patients with first episode psychosis. Patients in the first episode psychosis cohort were diagnosed with broad schizophrenia spectrum psychosis using the Diagnostic and Structural Manual of Mental Disorders, and an age and gender matched healthy control cohort was recruited. Assessment, including clinical data, laboratory serum analysis, psychotic symptoms, self-assessed lifestyle factors, and cognitive tests, were evaluated at baseline and at a 1-year follow-up.

The first episode psychosis cohort (n=132) and the healthy control cohort (n=83) were significantly different in demographic characteristics for age (26.7 vs 29.0 years old, P =.01), education (12.9 vs 14.2 years, P <.001), ethnicity (65.9% vs 98.3% white, P <.001), and smoking (45.5% vs 19.8%, P <.001). The first episode psychosis cohort had higher levels of total cholesterol (P =.003) and low-density lipoproteins (P =.001) when compared with the healthy controls at baseline. At follow-up there were no mean changes in lipid levels, but there were individual differences in the first episode psychosis cohort.

The first episode psychosis cohort had marked impairment across all areas, including cognitive function, verbal learning, processing speed, working memory, verbal fluency, and inhibition (P <.001, for all) when compared with the healthy controls at baseline. At follow-up, there was a main effect of time (F=17.60, P <.001) and a group by time interaction for verbal learning (F=6.86, P =.01).

Analyzing the association between lipid levels and cognition, the first episode psychosis cohort had a significant group by HDL interaction effect for verbal learning (F=11.12, P =.001), and increases in HDL were associated with increases in verbal learning in the first episode psychosis cohort when compared with the healthy control cohort (B=10.32, P =.001). Post hoc analysis indicated HDL levels were a stronger predictor for verbal learning (B=3.13, P =.007) than negative symptoms (B=−2.20, P =.001), positive symptoms (B=−1.76, P =.03), and remission status (B=8.42, P =.002).

Limitations of this study include differences in demographics and learning potentials between the 2 cohorts, potential biases in self-assessments, and inability to assess temporality.

The researchers of the study concluded that “antipsychotic-treated [patients with first episode psychosis] showed that during the first year of follow-up, an increase in serum HDL was associated with better cognitive performance.”

Reference
Gjerde PB, Simonsen CE, Lagerberg TV, et al. Improvement in verbal learning over the first year of antipsychotic treatment is associated with serum HDL levels in a cohort of first episode psychosis patients [published online April 27, 2019]. Eur Arch Psychiatry Clin Neurosci. doi: 10.1007/s00406-019-01017-w