Increasing rates of referrals for investigation of primary aldosteronism at a tertiary centre.

Aim: To describe the frequency and characteristics of patients referred for specialist investigation of primary aldosteronism (PA) in the lower North Island over a 5-year period, and the outcomes of those who received treatment.

Methods: Patients who underwent confirmatory testing or treatment for PA at Wellington Regional Hospital were retrospectively identified and data were collected from electronic clinical records.

Results: There has been a five-fold increase in both referrals and confirmatory testing for PA in 2021 compared to 2015. Compared to patients without PA, those eventually diagnosed with PA had a higher ARR, serum sodium, antihypertensive requirement and cardiovascular disease prevalence, as well as lower serum renin, potassium and GFR (all p <0.05), but similar blood pressure. Complete or partial clinical success was achieved in 96% of surgically treated patients compared with 70% of medically treated patients. Thirty-nine percent of patients experienced minor adverse effects with spironolactone and only one significant adverse event was experienced perioperatively.

Conclusions: The rate of referrals and confirmatory testing for PA are increasing in our region. Adrenalectomy and mineralocorticoid antagonist therapy are both safe and effective treatments, although minor adverse effects were common with spironolactone.