The Prime Diet Quality Score (PDQS), chronic disease and cause-specific mortality in UK Biobank: a prospective study

The Prime Diet Quality Score (PDQS) is a global food-based metric for assessing diet quality. We evaluated PDQS-measured diet quality in relation to mortality and major chronic disease outcomes in the UK Biobank. This population-based cohort study included UK adults (40–69 years) recruited in 2006–2010 and followed until 2021. PDQS was derived from ≥ 2 dietary recalls. Multivariable Cox regression estimated hazard ratios (HRs) and 95% confidence intervals (CIs) for total and cause-specific mortality, cardio-metabolic diseases (type 2 diabetes [T2D], cardiovascular disease [CVD], myocardial infarction [MI], stroke), respiratory diseases (chronic obstructive pulmonary disease [COPD], asthma), cancers (total, lung, colorectal, oesophageal, postmenopausal breast, prostate), neurodegenerative diseases (dementia, Parkinson’s, anxiety, depression), non-alcoholic fatty liver disease (NAFLD), chronic kidney disease (CKD), eczema, psoriasis, fracture, and osteoporosis. Among 124,851 participants (mean age 59 ± 8 years), those in the highest PDQS quartile had lower mortality risks: total (HR 0.80, 95% CI 0.73–0.88), cancer (0.87, 0.77–0.98), respiratory (0.56, 0.37–0.87), and neurodegenerative (0.61, 0.39–0.96). Chronic morbidity risks were lower for T2D (0.73, 0.66–0.81), MI (0.80, 0.71–0.90), ischemic stroke (0.86, 0.74–1.00), COPD (0.80, 0.69–0.94), total cancer (0.94, 0.88–0.99), lung cancer (0.75, 0.58–0.97), anxiety (0.85, 0.78–0.92), NAFLD (0.66, 0.56–0.77), and CKD (0.74, 0.69–0.80). Higher PDQS scores are linked to reduced mortality and chronic disease risk. PDQS is a practical tool for assessing diet quality in epidemiological research.