Associations of key diet-quality indexes with trajectory of multimorbidity: a prospective study in the UK Biobank

BACKGROUND: Dietary patterns have been associated with the morbidity and mortality of individual non-communicable diseases(NCDs). However, the impacts of baseline dietary patterns among the initially healthy population on the progression from healthy to first non-communicable disease (FNCD), subsequently to multimorbidity, and further to death remain unclear. METHODS: One hundred forty eight thousand eight hundred fifty eight participants free of cancer, cardiovascular disease(CVD), chronic respiratory disease(CRD), and type 2 diabetes(T2D) in the subsample of UK Biobank with 24 h recall data were included in our research. Multimorbidity was defined as the coexistence of at least two diagnoses of cancer, CVD, CRD, and T2D. Health outcome data was acquired from primary care data, inpatient hospital records, cancer registries and death registries. Multi-state model was used to analyze the impacts of four diet-quality indexes and key food components on the whole trajectory of multimorbidity. RESULTS: During a median follow-up of 12.5 years, 28,340 participants experienced at least one NCDs, 4,019 developed multimorbidity, and 4,815 dead. Four diet-quality indexes at baseline were all inversely associated with the risks of transitions from healthy to FNCD, from FNCD to multimorbidity, and from healthy to death, but not transitions from FNCD and multimorbidity to death. The HRs (95% CIs) across extreme quartiles of DASH index were 0.87(0.84-0.90) and 0.75(0.69-0.82) for transitions from healthy to FNCD and subsequent to multimorbidity. For transition from healthy to death, the HR (95% CIs) across extreme quartiles of DASH was 0.75(0.63-0.90). High fruits, vegetables, and whole grain were associated with lower risks of transitions from baseline to FNCD and subsequent to multimorbidity. But sugar sweetened beverage was associated with higher risks of these transitions. Furthermore, males, normal-weight and previous/current smoking participants appeared to derive the greater benefit from high diet-quality indexes, although the associations remained statistically significant in females, overweight/obesity and never smoking individuals. CONCLUSIONS: Our study indicated that healthy dietary patterns at baseline were associated with lower risks of progression from healthy to FNCD, subsequently to multimorbidity, and from baseline to death. These findings emphasize the critical role of maintaining a high-quality diet before NCD onset, as it may further contribute to preventing multimorbidity development.