We examined how age affects the association between sodium/potassium intakes and blood pressure.Design and method:
A total of 12,286 adults aged over 19 years without antihypertensive drugs were selected from data KNHANES, a nationally representative cross-sectional survey in Korea, 2010–2012. To evaluate how age affects the association between sodium/potassium intakes and blood pressure, we categorized the subjects into three age groups: 19–39 years, 40–59 years and over 60 years. We used a 24-hour dietary recall method to assess the sodium and potassium intakes. SUDAAN was used to analyze data while considering the sampling design. Multiple regression models included sodium and potassium intakes as well as energy intakes, body mass index, drinking status, smoking status, physical activity, income and age to control the confounding factors.Results:
There was no association between dietary sodium/potassium and blood pressure in younger Korean adults at 19–39 years olds after adjusting the confounding factors. However, the sodium intake was positively associated with systolic and diastolic blood pressure in 40–59 years old adults and was positively associated with diastolic blood pressure in over 60 years old adults. Potassium intakes was negatively associated with systolic blood pressure in 40–59 years old adults and was negatively associated with systolic and diastolic blood pressure in over 60 years old adults. Sodium to Potassium ratio was also positively associated with both systolic and diastolic blood pressure in adults over 40 years of age.Conclusions:
Low sodium and high potassium intakes were associated with low blood pressure in Korean adults over 40 years old but had no association in younger adults at 19–39 years old. Therefore, low sodium and high potassium diet might be more beneficial for the middle aged and older adults.