Cardio-metabolic risk factors during childhood in relation to lung function and asthma

Background Cardio-metabolic risk factors might have an adverse effect on respiratory outcomes, but associations in children are unknown. We aimed to study the longitudinal associations of cardio-metabolic risk factors with lung function and asthma at school age. We also examined whether any association was explained by child's body mass index (BMI). Methods In a population-based cohort study among 4988 children, cardio-metabolic risk factors were measured at 6 and 10 years and included blood pressure, cholesterol, triglycerides, insulin, and C-reactive protein (CRP) concentrations. At age 10 years, lung function was measured by spirometry and current physician-diagnosed asthma was assessed by questionnaire. Results After adjustment for confounders, child's BMI, and multiple testing, we observed that a higher diastolic blood pressure at the age of 6 years was associated with a higher forced vital capacity (FVC) at the age of 10 years (Z-score difference (95% CI): 0.05 (0.01, 0.08), per SDS increase in diastolic blood pressure). Also, child's CRP concentrations above the 75th percentile at both ages 6 and 10 years were related to a lower FVC as compared to CRP concentrations below the 75th percentile at both ages (Z-score difference (95% CI) -0.21 (-0.36, -0.06)). No consistent associations of other cardio-metabolic risk factors with respiratory outcomes were observed. Conclusion Blood pressure and CRP, but not lipids and insulin, were associated with lower lung function but not with asthma. The underlying mechanisms and long-term effects of these associations require further investigation.

Automated summary

This study found that higher diastolic blood pressure at age 6 was associated with higher forced vital capacity at age 10, while elevated CRP concentrations above the 75th percentile at both ages 6 and 10 were related to lower FVC. No consistent associations were observed with other cardio-metabolic risk factors. Further investigation is needed to understand the underlying mechanisms and long-term effects of these associations.