Changes in blood sugar and weight during the first 90 days of antipsychotic treatment are significantly more rapid than at any other point, according to new research published in The Lancet Psychiatry. The study, led by researchers at UCL, examined health records from nearly 97,000 adults in England with severe mental illness.
Rapid metabolic shifts
The analysis focused on four common medications: Olanzapine, Quetiapine, Risperidone, and Aripiprazole. Data was collected from two years prior to treatment initiation through two years after, tracking HbA1c levels and body weight. The findings indicate that the highest rates of change occur immediately following the start of medication.
During the first 90 days, HbA1c, a marker of average blood sugar, increased approximately 14 times faster than before treatment began, while weight gain occurred about nine times faster. For patients taking Olanzapine, the increases were even steeper, with HbA1c rising around 50 times faster and weight around 10 times faster in the same timeframe.
Read Also: Coffee and Genes Shape Breast Milk Composition
Demographic differences
The study identified disparities in how the drugs affected men and women. Among female patients, HbA1c rose around 24 times faster and weight increased about 12 times faster during the first three months compared to the pre-treatment period.
People with prediabetes showed a higher risk of progressing to type 2 diabetes. Approximately 19% of patients with prediabetes developed type 2 diabetes within two years, compared to 3% of those starting with normal blood sugar levels.
The research was funded by the National Institute for Health and Care Research (NIHR), with additional support from UK Research and Innovation (UKRI) and various biomedical research centers at UCL. Schizophrenia affects around 23 million people worldwide, while around 37 million live with bipolar disorder. Not only do these conditions have a major impact on a person’s thoughts, feelings and daily life, but they can also substantially reduce life expectancy compared to the general population, with patients typically dying around 10-20 years earlier than average. This is primarily driven by greater incidence of cardiovascular and metabolic disease. Second-generation antipsychotics are known to contribute to this metabolic burden, as many cause weight gain and increase the risk of diabetes.