SAN DIEGO — Antidepressant use could be associated with an increased risk of metabolic syndrome among adult psychiatric inpatients, Stephen B. Woolley, D.Sc., reported at the annual meeting of the American Psychiatric Association.
Dr. Woolley and his colleagues found a 40% increased risk of metabolic syndrome in adult psychiatric inpatients taking an antidepressant. Their study also found that 70% of the inpatients had at least one abnormal marker for metabolic syndrome—putting them at risk for cardiovascular disease, and going on to develop metabolic syndrome and diabetes, said Dr. Woolley of the Institute of Living at the Hartford [Conn.] Hospital.
The investigators reviewed records from 2,075 consecutive inpatients discharged from the Institute of Living in 2005 and 2006, and looked for the presence or absence of each of the five criteria for metabolic syndrome from the Adult Treatment Panel III.
The criteria are central adiposity, measured by waist circumference (greater than 40 inches in men and 35 inches in women); fasting blood triglycerides greater than or equal to 150 mg/dL; an HDL cholesterol level less than 40 mg/dL in men and 50 mg/dL in women; blood pressure greater than or equal to 130/85 mm Hg; and a fasting glucose greater than or equal to 110 mg/dL.
The presence of any three of the criteria indicates metabolic syndrome.
The study by Dr. Woolley and his colleagues also found that taking an antidepressant was most strongly associated with an 80% increased risk of dyslipidemia among the inpatients with schizophrenia, a 60% increased risk among those with schizoaffective disorder, and a 120% increased risk among those with major depressive disorder.
Because the study looked only at patients' hospital records, the investigators were unable to determine whether the use of selective serotonin reuptake inhibitors or other antidepressants by themselves might have been the cause of those increased risks, Dr. Woolley said.
Another explanation could be that depressed patients have greater obesity, are more sedentary, and generally live harder lives.
“We found a higher risk in all patients on antidepressants,” Dr. Woolley simply noted.
If the findings are related to something other than the antidepressants specifically, they might be less surprising, said Dr. John W. Goethe, director of the Burlingame Center for Psychiatric Research and Education at the Institute of Living, who presented secondary results from the study.
That is because there is already an observed connection: Metabolic syndrome has been shown to predict a higher risk of later major depressive disorder, Dr. Goethe said.
Overall, the study found that the presence of metabolic syndrome in the patients was 25%, with a range of 24% for patients with bipolar disorder, to 30% for patients with schizophrenia, to 41% for patients with schizoaffective disorder.
Besides the use of antidepressants, another significant predictor of metabolic syndrome in the patients was the use of two antipsychotics, which increased the risk 2.4 times (almost four times for schizophrenia patients). Another predictor was age greater than or equal to 40 years, which increased the risk three times.
The study also found that patients with bipolar disorder were 11 times more likely to have hypertension, compared with patients with other diagnoses, and patients with major depressive disorder were 13 times more likely to have hypertension.
In another part of the study, the investigators took the 317 patients with a depressive disorder, and matched them to figures from the National Health and Nutritional Examination Survey (NHANES) database of the general population, Dr. Goethe said.
Eighty-eight percent of the bipolar and major depressive disorder patients met at least one metabolic syndrome criteria, and 32% met three criteria.
That compared with 71% of the general population reported by the NHANES survey to meet one criterion, and 24% reported to have the metabolic syndrome.
More than 50% of the patients met the waist criteria, and 24% met the dyslipidemia criteria, Dr. Goethe noted.