SENSITIVE ASSAY OF THYROID-STIMULATING HORMONE IN DEPRESSED-PATIENTS

A decreased thyroid stimulating hormone (TSH) response to thyrotropin releasing hormone (TRH) has been noted in major depression. Some autho rs found a positive correlation between baseline TSH levels and TSH re sponse to TRH, especially with sensitive assays of TSH. Serum TSH was assayed by a sensitive method in 55 depressed patients and 38 healthy volunteers. Patients were subclassified according to DSM-III as suffer ing from major depression (n = 40) and non-major depression (n = 15), The patients' mean score on the Hamilton Rating Scale for Depression ( HRSD) was 50 (SD = 10). The TSH value was significantly lower in depre ssed patients compared with healthy control subjects, and in major com pared with non-major depression. No differences in TSH levels distingu ished the various subtypes of major depression, There was a significan t negative correlation between global HRSD scores and TSH concentratio ns. The most anxious patients tended to have significantly lower TSH v alues compared with the least anxious subjects. Total HRSD insomnia sc ores correlated negatively with TSH concentrations after log transform ation. The sensitive determination of TSH may also provide an index of thyroid function in depression that is simpler to implement than meas urements of the TSH response to TRH.