Reply to comment on: Urinary sodium excretion and its association with blood pressure in Nigeria: A nationwide population survey

Abstract

We thank Khitan and colleagues 1 for their comments on our recent article. 2 We discussed some of the issues raised in the limitations section of the article; however, we wish to offer further explanations. Khitan and colleagues were concerned about the interpretation of our findings in terms of reverse causality. We think that this is outside the scope of the research. The cross-sectional design of our study was not intended to explore the causal link between sodium and hypertension since temporality of association is a strong criterion for causality.Cross-sectional studies at best will generate hypothesis which should be tested further using appropriate study designs. We however agree with the assertion that salt intake may be affected by several factors including medical conditions such as hypertension and heart failure.We made effort to adjust for the pre-existing medical conditions. We achieved this by enquiring from patients if they were on antihypertensive medications or had previously been advised by any health professional to reduce salt intake on account of one cardiovascular disease or the other. Despite adjusting for these factors (use of antihypertensive drug and reduction in salt intake), the association of salt intake with blood pressure remained weak and non-significant.Judging from the median urinary creatinine value we reported, they