Prolonged Hypokalemia and Delayed Diagnosis of Primary Aldosteronism: Clinical Course and Risk Factors

CONTEXT: Primary aldosteronism (PA) is a common cause of hypertension (HT). However, diagnosis is often delayed, leading to poorer clinical outcomes. Hypokalemia with HT is characteristic of PA, and is an indication for screening. OBJECTIVE: We evaluated if patients with PA had prolonged hypokalemia before diagnosis, the subsequent biochemical/clinical control, and factors associated with delayed diagnosis. METHODS: Our study included all PA patients with hypokalemia diagnosed between 2001 and 2022. Delayed diagnosis was defined as duration of hypokalemia of more than 1 year from first occurrence to first evaluation by a PA specialist. Patients were reassessed post adrenalectomy using the Primary Aldosteronism Surgery Outcomes criteria. We performed multivariable analysis to assess for factors associated with delayed diagnosis. RESULTS: Among 240 patients with PA who presented with hypokalemia, 122 (51%) patients had delayed diagnosis, with prolonged hypokalemia of median duration 4.5 years (range, 2.4-7.5 years). Patients with delayed diagnosis were older, had longer duration of HT, higher pill burden, lower renal function, and more prevalent cardiovascular disease. Factors associated with delayed diagnosis included older age, presence of hyperlipidemia, and less severe hypokalemia (serum potassium >3.0 mmol/L). Compared to patients with early diagnosis, a lower proportion of those with delayed diagnosis underwent adrenal vein sampling (73% vs 58%) (P < .05). Sixty of 118 (50.8%) nondelayed, and 39 of 122 (32.0%) patients with delayed diagnosis, underwent surgery. CONCLUSION: Despite manifestation of hypokalemia, many patients with PA fail to be promptly screened. Greater emphasis in HT guidelines, and efforts to improve awareness of PA among primary care physicians, are urgently needed.