Hypertension and blood pressure profiles in patients with acute intermittent porphyria: a prospective case-control study.

Background
Acute intermittent porphyria (AIP), a rare disorder of heme biosynthesis, may manifest with neurovisceral crises affecting autonomic regulation. This study aimed to assess blood pressure (BP) pattern and hypertension prevalence in AIP patients.Methods
This prospective case-control study included patients with overt AIP (at least one attack) and a control group, matched by age, sex and body mass index (BMI). All participants underwent detailed clinical assessment, biochemical and cardiovascular phenotyping with 24-hour BP monitoring and echocardiography in the tertiary centers.Results
The study comprised 90 patients with AIP, of whom 42 (47%) were assessed also during attacks, and 90 controls (mean age 39±11 years, 79% female). Hypertension was more prevalent in AIP patients (58%) compared to controls (31%, P < 0.001). Additionally, AIP patients showed higher mean systolic BP (SBP, 123.7 ± 13.1 vs. 116.9 ± 10.8 mmHg, P < 0.001) and diastolic BP (DBP, 77.7 ± 9.5 vs. 73.2 ± 7.1 mmHg, P < 0.001). Nocturnal hypertension, a non-dipping BP pattern and left ventricular hypertrophy were more frequently observed in the AIP group. Age, BMI and history of paresis were independently associated with hypertension in AIP patients. During AIP attacks, BP was significantly higher than during remission (SBP 135.4 ± 18.4 vs. 121.9 ± 12.8 mmHg, P < 0.001; DBP 84.6 ± 13.8 vs. 76.5 ± 10.1 mmHg, P < 0.001). The differences correlated with changes in the plasma concentrations of normetanephrine.Conclusion
AIP is associated with a higher prevalence of hypertension, an unfavourable nocturnal BP profile and cardiac structural changes. BP rises significantly during AIP attacks, which is likely mediated by catecholaminergic surges. This underscores the need for cardiovascular monitoring in AIP patients.Clinicaltrials
gov, Number NCT05882136.