Association of Multimorbidity and Kidney Function Decline in Older Age

Although chronic conditions have been linked with a decline in kidney function, the role of multimorbidity (defined as the presence of 2 or more conditions) in this decline, as well as patterns of multimorbidity, remain unclear. Giorgi Beridze MD, MMSc, attempted to address this gap with an analysis of 3,094 patients from the Swedish National Study on Aging and Care in Kungsholmen. The mean age of participants was 73.9 years, 87% had multimorbidity, and they were followed up for 15 years. 

Latent class analysis was used to identify multimorbidity patterns. The researchers used joint models and Cox regression models, respectively, to examine the associations between multimorbidity and subsequent absolute and relative (≥25% decline from baseline) changes in estimated glomerular filtration rate (eGFR; measured using the creatinine-based Berlin Initiative Study equation).

An independent dose-response relationship was observed between the number of chronic conditions and absolute (β, –0.05; 95% CI, –0.07 to –0.03) and relative (hazard ratio [HR], 1.23; 95% CI, 1.17- 1.29) declines in eGFR. The researchers identified 5 patterns of multimorbidity: (1) the unspecific, low burden pattern demonstrated the lowest morbidity burden and was used as the reference category; (2) the unspecific, high burden pattern demonstrated accelerated absolute (β, –0.15; 95% CI, –0.26 to –0.05) and relative (HR, 1.45; 95% CI, 1.09-1.92) declines; (3) the cardiometabolic pattern also showed accelerated absolute (β, –0.77; 95% CI, –0.98 to –0.55) and relative (HR, 3.45; 95% CI, 2.27-5.23) declines, (4) the cognitive and sensory pattern showed accelerated relative decline (HR, 1.53; 95% CI, 1.02-2.31); and (5) the psychiatric and respiratory pattern demonstrated no associations.

In summary, multimorbidity showed a strong association with an accelerated kidney function decline in individuals of older age, and those with a cardiometabolic multimorbidity had a particularly increased risk. “Increased monitoring and timely interventions may preserve kidney function and reduce cardiovascular risks in individuals presenting with conditions that are characteristic of high-risk multimorbidity patterns,” the authors wrote.

Source: Journal of the American Geriatrics Society