Multimorbidity patterns and mortality in older adults: a two-cohort pooled analysis

Different multimorbidity patterns can affect health trajectories and influence survival. We investigated their association with mortality in two population-based cohorts of older adults. Two Italian cohorts of randomly selected individuals (60–79 years old) from general population: CUORE (baseline 2008–2012) and Moli-sani (baseline 2005–2010). Latent Class Analysis used to identify homogeneous groups of multimorbid individuals (≥ 2 diseases) with similar underlying disease patterns. Cox regression models used to assess the association of multimorbidity patterns and all-cause mortality (end of follow-up 12/31/2019). Results pooled in a random-effects meta-analysis. Total samples of 3,695 individuals in CUORE (48% male, mean age 68.8 years [SD 5.6]) and 7,801 in Moli-sani (51% male, mean age 68.2 years [SD 5.4]). In both cohorts, six multimorbidity patterns were identified and named after their overexpressed diseases: hypercholesterolemia; metabolic, depression and cancer; cardiometabolic and respiratory; gastrointestinal, genitourinary and depression; respiratory; unspecific (i.e., no diseases overexpressed). Overall mortality rates were 1.66 per 100 person/years in CUORE and 1.85 per 100 person/years in Moli-sani. Compared to the multimorbidity-free group (< 2 diseases), individuals displaying a cardiometabolic and respiratory pattern showed the highest mortality (pooled HR 2.62, 95% CI 2.15–3.10), followed by unspecific (pooled HR 1.45, 95% CI 1.21–1.68), respiratory (pooled HR 1.33, 95% CI 1.01–1.64) and gastrointestinal, genitourinary and depression (pooled HR 1.33, 95% CI 1.06–1.60). Multimorbidity patterns in older adults are differentially associated to shorter survival. Their identification may help optimize clinical management by improving risk stratification, allowing for more targeted prevention and intervention strategies.