Polymorphisms in gene MMP-2 modify the association of cadmium exposure with hypertension risk.

Background: Cadmium exposure has been inconsistently related with hypertension. However, epidemiologic data on the genetic susceptibility to the hypertensive effect of cadmium exposure are limited.

Objectives: We investigated whether the associations between cadmium exposure and hypertension risk differed by genetic polymorphisms in MMPs genes.

Methods: The present study of 497 hypertension cases and 497 healthy controls was conducted in a Chinese population. Urinary cadmium levels were measured with inductively coupled plasma-mass spectrometer (ICP-MS). Multivariable logistic regression models were analyzed after controlling major confounders.

Results: Within the multivariable logistic regression models, compared with the lowest tertile, the highest tertile of urinary cadmium had a 1.33-fold (95% CI: 1.01, 1.93) increased risk of hypertension. Carriers of rs243865 T allele and rs243866 A allele in MMP-2 were suggested to have increased risks of hypertension. The associations of urinary cadmium with hypertension risk were modified by rs14070 (P-value for interaction = 0.022) and rs7201 (P-value for interaction = 0.009) in gene MMP-2. Positively significant trends for increasing odds of hypertension with cadmium levels were observed among the wild types of rs14070 and rs7201, respectively.

Conclusions: Increasing urinary cadmium concentrations were positively associated with hypertension risk in a Chinese population, and the associations were modified by polymorphism of rs14070 and rs7201 in gene MMP-2.