Schizophrenia has often been associated with a reduced skin flush response to niacin. Blunted response suggests potential disturbance in phospholipid metabolism.

We performed niacin skin tests in patients with schizophrenia, their first-degree relatives and healthy controls.

To examine possible differences in skin flush response to niacin.

We examined 51 patients (female 49%, age 33.1 years, SD 11), with schizophrenia-spectrum disorders, 51 matched healthy controls (female 49%, age 33 years, SD 12.1), and 21 first-degree relatives (female 61,9%, age 49,5 years, SD 17,6, one affected, others non-affected). The Positive and Negative Syndrome Scale and the Mini International Neuropsychiatrie Interview were used to assess psychopathology and diagnosis, respectively. The non-invasive niacin skin flush test was used to assess vasodilatative reaction to four different concentrations of niacin on the forearms of subjects.

We found no differences in total scores on the niacin skin flush test between the three groups (p = 0.774). Mean scores were 60.27 (SD 14.2) in healthy controls, 58.84 (SD 10.2) in patients and 58.48 (SD 9.4) in first-degree relatives.

Contrary to our expectations we did not find a significantly blunted niacin skin flush reaction in patients with schizophrenia-spectrum disorders compared to healthy controls or 1st degree relatives.