Relation between bipolar mood disorder and seasonality of serum lipids

Introduction: The association between mood disorders and serum lipid levels has been evaluated for many years. Recently, it has been showed that serum lipid levels may have seasonal changes. From here, we aimed to evaluate seasonality of serum lipids in bipolar disorder which may be related with episodic and seasonal features. Method: Mean serum lipid levels and seasonal differences of serum lipid levels were compared between 79 patients with bipolar disorder type I, who were followed in Rasit Tahsin Mood Disorders Outpatient Unit of Bakırköy Prof. Dr. Mazhar Osman Research and Training Hospital for Psychiatry, Neurology & Neurosurgery and 38 healthy controls, for one year. Results: Mean cholesterol and triglyceride levels were similar between patients and controls for all seasons. Mean serum HDL levels were lower for all seasons, except winter in patients with bipolar disorders. When seasonal changes in lipid levels were evaluated, the only significant difference among the two groups was changes in spring HDL levels. Conclusions: This is the first study that evaluates seasonality of lipid levels in bipolar patients, although it has some limitations. Long term, big sample-sized follow-up studies are required to get strong evidence for understanding aetiology of illness related with lipid levels among bipolar patients.