Association of heat shock protein70-2 genotypes with hypertension among textile workers occupationally exposed to noise.

Noise exposure is a primary cause of hearing loss with a broad range of auditory and non-auditory effects. It is one of the occupational health risks in both developed and industrialized countries. Heat shock proteins (HSPs) are induced after severe noise exposure. Those proteins protect the ear from damage following excessive noise exposure. This protection showed high variability between individuals. The aim of the study was to investigate the variation in hearing loss and blood pressure in textile workers and its association with genetic predisposition related to HSP70 genes. Also, the role of smoking was studied. We genotyped HSP-70 (hsp70-1, hsp70-2, and hsp70-hom) genes in 109 textile workers working in a noisy environment. Diastolic and systolic blood pressure was measured for workers. Hearing was assessed using an audiogram. We reported significant variation in HSP70-homo genotypes among smoker workers and nonsmoker ones. Only HSP70-2 genotypes were associated with high significant variations in both systolic and diastolic blood pressure among textile workers. Positive correlation between duration of exposure and both systolic (P < 0.047) and diastolic blood pressure (P < 0.033) was observed among workers. Our study recorded that HSP70-2 genotypes were associated with hypertension among textile workers with absence of that association with either HSP70-1 or HSP70-homo genotypes. We also confirmed the relationship between noise exposure and blood pressure (both systolic and diastolic blood pressure). Furthermore, significant variation was shown in HSP70-hom genotypes among smoker and nonsmoker workers.