Correlation between Hyperprolactinemia and Systemic Lupus Erythematosus Disease Activity Level

Recent accumulated evidence suggests that prolactin is an important immunomodulator and might have a role in the pathogenesis of systemic lupus erythematosus(SLE). Stimulating immune system, this peptide hormone increases the severity of SLE. The purpose of our study was to assess the frequency of hyperprolactinemia in women with SLE and to evaluate its correlation with the disease activity. This descriptive-analytical study was carried out on 35 women with SLE (patient group) who had been randomly selected and 60 healthy cases(control group) who matched patients in terms of sex and age. Disease activity was assessed by using SLE Disease Activity Index(SLEDAI). Patients with a score above 10 were considered active. In both groups, prolactin levels were determined by Immunoradiometric Assay(IRMA). Hyperprolactinemia could be seen in 28.5% of patient group and 3.3% of control group(P<0.05), which indicates a significant difference in the incidence rate of hyperprolactinemia in the two groups. Mean prolactin level in patient group was significantly higher than this level in control group(770±860 versus 341±335, P.value=0.0078). Patients with active disease showed a trend toward higher mean prolactin levels than inactive patients. SLE was active in 90% of hyperprolactinemic patients, while in normoprolactinemic patients active disease was found only in 36% of them. A statistically significant correlation was found between prolactin levels and SLE disease activity index.