Age-related changes in prevalence and symptom characteristics in kidney deficiency syndrome with varied health status: a cross-sectional observational study

This study aimed to reveal the age-related changes in prevalence and symptom characteristics in kidney deficiency syndrome (KDS) with varied health status.

This cross-sectional observational study was conducted in6 hospitals. Investigators queried participants aged 20–79 about their health, including symptoms if any, and completed questionnaires to collect participants responses. Prevalence, severity, and frequency of KDS and other relevant parameters were observed and recorded. Comparative analysis of countable variables, including prevalence, was performed by frequency analysis and χ² test and expressed as a composite ratio. Comparative analysis of quantitative scores of the severity and frequency of symptoms was performed by the rank-sum test. Regression analysis of the correlation of KDS with potential contributing factors was performed by non-conditional binary logistic stepwise regression of numerical variables.

Prevalence of KDS in healthy and unhealthy participants correlated with increasing age (P < 0.05). In those with chronic disease, KDS prevalence was comparatively high, but the trend was not obvious. KDS prevalence in participants age 20–39 showed an increasing trend with deteriorating health (P < 0.05). Compared to healthy individuals, KDS prevalence in subhealthy persons and those with chronic disease showed an increasing trend (P < 0.05) in the 40–59 and 60–79 age groups, whereas there was no difference between subhealthy persons and those with chronic disease age 40–59 and 60–79. Symptom severity scores of KDS showed an increasing trend with increasing age and deteriorating health status (P < 0.05). Higher symptom frequency scores were also positively correlated with increasing age (P < 0.05), but health status deterioration was not significantly correlated (P > 0.05). Age, health status, lower back pain, shin soreness or heel pain, tinnitus or deafness, hair loss or loose teeth, incomplete bladder emptying or incontinence, and sexual dysfunction or infertility were potential factors contributing to KDS (P < 0.05), but age was the only independent variable for which OR >1. Moreover, the distribution of typical KDS-related symptoms showed dramatic regularities.

Prevalence and symptom characteristics of KDS were found to increase consistently with increasing age and deteriorating health status. Kidney deficiency may be an important mechanism of aging in the subhealthy and chronic disease states.