Urinary sodium excretion and blood pressure in chronic psychiatric in-patients

Abstract

Studies of populations or communities with no rise in blood pressure (BP) with advancing age and low prevalence of hypertension, may provide aetiological clues on the cause of hypertension. Within westernised societies, low blood pressures have been reported amongst chronic psychiatric in-patients and closed order secluded nuns.To investigate factors associated with BP in chronic psychiatric in-patients, we surveyed the BP and lifestyle factors in 89 such subjects in low security wards in three psychiatric hospitals. The average age of examines was 48.1 years (s.d. 15.8) and the patients had been in hospital for a mean of 8.6 years (range 1.1 to 51.7 years). The mean systolic and diastolic blood pressures of this group were 122.0 mm Hg (s.d. 14.2) and 76.9 mm Hg (s.d. 8.5) respectively. This was lower than pressures obtained when they were admitted to hospital (mean systolic BP change ؊17.1 mm Hg (s.d. 14), paired t-test P Ͻ 0.001; mean diastolic BP change ؊3.7 mm Hg (s.d. 12.2), paired t-test P Ͻ 0.001). BP at examination was significantly correlated with the urinary sodium to