Daily sodium intake influences the relationship between angiotensin‐converting enzyme gene insertion/deletion polymorphism and hypertension in older adults

Abstract

The angiotensin-converting enzyme insertion/deletion (I/D) gene polymorphism has been widely reported as being associated with hypertension; however, most studies do not consider environmental/behavioral factors. This study aimed to investigate the relationship among angiotensin-converting enzyme insertion/deletion gene polymorphism, environmental/behavioral factors, and hypertension in community-dwelling elderly individuals. All community-dwelling older adults from Aiquara, Bahia, Brazil, were invited to take part in this study. After exclusions, 234 elderly participants were submitted to a data collection, which included sociodemographics, lifestyle and health status questionnaires, clinical assessment, and blood withdrawal. From the blood samples, the gene polymorphism was identified through polymerase chain reaction and patients grouped as II or D allele carriers (ID and DD genotypes). Hypertension was defined by self-report of the condition and confirmed by antihypertensive drug treatment. Chi-square test was used to identify differences in the proportions distributed between groups of each dependent variable (ie, genotype, diagnosis of hypertension, and blood pressure state from medicated patients with hypertension). The prevalence of hypertension was 59.3% and was associated with diabetes mellitus and obesity, but not with angiotensin-converting enzyme insertion/deletion gene polymorphism. However, carriers of the II genotype, a salt-sensitivity genotype, exhibited a significantly greater estimated sodium intake. In addition, among medicated elderly patients with hypertension, II genotype carriers exhibited poor blood pressure control, despite similar antihypertensive drug treatment in D allele carriers, while exhibiting a greater estimated sodium intake. Our results provide new evidence regarding the interaction of genetic and environmental/behavioral factors in the genesis of hypertension among elderly patients, as well as in blood pressure control in medicated elderly patients with hypertension.

Interactions between genetic and lifestyle factors on cardiometabolic disease-related outcomes in Latin American and Caribbean populations: A systematic review

“…Similarly, among those with a high calcium intake (573.3 mg), carriers of the “ T ” allele of Bradykinin Receptor B2 ( BDKRB2 ) SNP rs1799722 had significantly higher SBP ( P interaction = 0.015) and diastolic BP (DBP) ( P interaction = 0.014) than carriers of the “ CC ” genotype ( 81 ). In line with these findings, a case-control study of 234 elderly people ( 82 ) reported an interaction between sodium intake and angiotensin-converting enzyme ( ACE ) SNP rs4646994 on the risk of hypertension, where carriers of the “ I/I ” genotype with a high sodium intake (>2 g/day) had an increased risk of hypertension ( P interaction = 0.007). Furthermore, in a cross-sectional study of 1298 healthy adults ( 83 ), those carrying the “ T ” allele of Cytochrome B-245 Alpha Chain ( CYBA ) ( p22phox ) with more than 86.5 mEq sodium per 12 h of urine collection, had increased SBP ( P interaction < 0.001) and DBP ( P interaction = 0.011).…”

“…The interaction between micronutrients and genetic variants on cardiometabolic traits was examined by five Brazilian studies (81)(82)(83)(84)(85). A cross-sectional study of 335 healthy young adults (81), observed a pronounced increase in systolic blood pressure (SBP) (P interaction = 0.016) among carriers of the "G" allele of Angiotensinogen (AGT) SNP rs699 with a higher plasma magnesium (209.3 mg).…”

Practical applicability of genetics for the prevention and treatment of hypertension

“…Data from this study, from other genetic polymorphisms that have already been discovered and others that have yet to be unveiled, will serve to form an interaction network that may explain the genetic influence on the development and treatment of hypertension. The relevance of this theme has been noted by several research groups that have devoted attention to the study of single nucleotide polymorphism that may be affecting the etiology of arterial hypertension 15 responses to sodium intake, 16,17 only among more recent articles published in the Journal of Clinical Hypertension.…”