Severe α-antitrypsin deficiency associated with lower blood pressure and reduced risk of ischemic heart disease: a cohort study of 91,540 individuals and a meta-analysis.

BACKGROUND

Increased elastase activity in α-antitrypsin deficiency may affect elasticity of the arterial walls, and thereby blood pressure and susceptibility to cardiovascular disease. We hypothesized that severe α-antitrypsin deficiency is associated with reduced blood pressure and susceptibility to cardiovascular disease.

METHODS

We genotyped 91,353 adults randomly selected from the Danish general population and 187 patients from the Danish α-Antitrypsin Deficiency Registry and recorded baseline blood pressure, baseline plasma lipids and cardiovascular events during follow-up. 185 participants carried the ZZ genotype, 207 carried the SZ genotype and 91,148 carried the MM genotype.

RESULTS

α-Antitrypsin deficiency was associated with decreases in blood pressure of up to 5 mmHg for systolic blood pressure and up to 2 mmHg for diastolic blood pressure, in ZZ vs SZ vs MM individuals (trend test, P's ≤ 0.01). Plasma triglycerides and remnant cholesterol were reduced in ZZ individuals compared with MM individuals (t-test, P's < 0.001). α-Antitrypsin deficiency was associated with lower risk of myocardial infarction (trend test P = 0.03), but not with ischemic heart disease, ischemic cerebrovascular disease or hypertension (trend test, P's ≥ 0.59). However, when results for ischemic heart disease were summarized in meta-analysis with results from four previous studies, individuals with versus without α-antitrypsin deficiency had an odds ratio for ischemic heart disease of 0.66 (95% CI:0.53-0.84).

CONCLUSIONS

Individuals with severe α-antitrypsin deficiency have lower systolic and diastolic blood pressure, lower plasma triglycerides and remnant cholesterol, reduced risk of myocardial infarction, and a 34% reduced risk of ischemic heart disease.