What’s more, despite adjustment for a range of covariates (age, sex, BMI, smoking, alcohol, education, occupation, hypertension, diabetes, hyperlipidemia, and self-reported kidney disease), we were unable to measure important potential confounders — notably nutritional status/iron indices (ferritin, transferrin saturation), systemic inflammatory markers (CRP, IL-6), detailed medication histories (including antidepressants and anti-inflammatory drugs), and psychosocial stressors. Here, CRP is linked to Hypertension.