Effect of lifestyle and life-course factors on adulthood kidney insufficiency

Background. Chronic kidney disease represents a major effect on global health. The risk factors for development of kidney disease are low nephron number or nephron loss, acute and chronic kidney injuries and diseases. There is not enough knowledge on the risk factors for kidney diseases from childhood and adolescence, especially knowledge on lifestyle factors and their effect on later adulthood kidney insufficiency is needed.

Methods. We set out to study lifestyle and life-course risk factors from childhood on early kidney insufficiency in adulthood from Northern Finland Birth Cohort 1966. Kidney insufficiency was defined as abnormal plasma creatinine values at the follow-up in the age of 46 years. The abnormal plasma creatinine values are > 90 micromole/l for females and >100 micromole/l for males. The study group was formed from the 5794 individuals whose plasma creatinine values were available in the cohort. The data were gathered from maternal and childhood/adolescence and adulthood questionnaires and examinations at 14-, 31- and 46-year-old follow-up in the cohort. Logistic regression was used to analyse the relationship between kidney insufficiency and the studied variables.

Results. Altogether, there were 40 individuals with abnormal plasma creatinine values and 5754 with plasma creatinine values within normal limits. Birth weight, maternal smoking or body mass index (BMI) or smoking, alcohol use, other long-term disease or weight at 14 years of age or running capacity for 2 kilometres at 31 years of age, or BMI, smoking, alcohol consumption or impaired glucose metabolism at 46 years of age were not predictive of early kidney insufficiency at the age of 46, whereas sex OR 0.180 (95% CI 0.079-0.413, P < 0.001), fitness score including body composition measurements OR 1.121 (95% CI 1.048-1.199, P < 0.001) and serum fasting urea values OR 2.169 (95% CI 1.561-3.015, P<0.001) and systolic blood pressure OR 0.925 (95% CI 0.867-0.987, P = 0.019) and diastolic blood pressure OR 1.108 (95% CI 1.011-1.213, P=0.028 at the age of 46 were predictive with early kidney insufficiency in this setting.

Conclusions. Maternal, childhood/adolescence or young adult to midlife lifestyle factors did not predict kidney insufficiency at the age of 46 years in this cohort, but male sex, higher fitness score as higher muscle to fat ratio and more balanced body composition and higher plasma fasting urea measurement values were associated with early kidney insufficiency. This emphasizes the need for future studies in kidney health and focus on sex differences and healthy nutrition, also healthy protein intake, and good fluid balance in normal life and hard physical activity when studying early kidney insufficiency.