Introduction:

The burden of kidney cancer negatively impacts a patient's physical and mental health from diagnosis, to treatment, and into survivorship. It is crucial to consider modifiable behavioral factors in order to improve quality of life outcomes in this population. We investigated the role of self-reported exercise or physical activity among a cohort of kidney cancer patients and survivors using the national Behavioral Risk Factor Surveillance System (BRFSS) between the years 2016 and 2020. We hypothesize that a lack of physical activity or exercise is associated with worse physical and mental health.

Methods:

This is a cross-sectional retrospective study of BRFSS (years 2016 to 2020) survey participants who self-reported having ever been diagnosed with kidney cancer. Descriptive characteristics of the identified cohort were calculated (Table 1). To test our hypothesis, we used multivariable logistic regression modeling analyses (MVA) to assess the outcomes of (a) 14+ days per month when mental health was not good and (b) 14+ days per month when physical health was not good. In both models, we adjusted for gender, age, treatment status, income, marital status, smoking status, and BMI (Table 2). An institutional review board waiver was obtained given that this is de-identified data. Two-sided statistical significance was defined as P<0.05. All statistical analyses were performed using Stata v.17.0 (StataCorp, College Station, TX, USA).    

Results:

Out of 2,193,981 survey participants, we identified 576 kidney cancer patients and survivors. 217 (37.7%) reported no physical activity or exercise in the last 30 days, whereas 358 (62.3%) reported physical activity or exercise in the last 30 days (Table 1). In our MVA modeling, those who were active were significantly less likely to report worse mental status compared to those who were not active (OR 0.41, 95% CI 0.20 – 0.85, p=0.02). Moreover, physical activity and exercise had similar results for the outcomes of poor physical health (OR 0.44, 95% CI 0.27 – 0.72, p<0.01). Additional results can be seen in Table 2. Standard C-statistic assessment for our MVA models yielded a Hosmer-Lemeshow test of p=0.59 for the mental status model and p=0.16 for the physical status model. Receiver operating characteristics (ROC) showed an area under the curve (AUC) of 0.80 and 0.75, respectively.    

Conclusion:

In our kidney cancer cohort, those who reported physical activity and exercise were significantly less likely to report poor mental and physical health. Our results highlight the importance of exercise and physical activity as a modifiable behavioral risk factor to improve quality of life in this population.  We postulate that physical activity may serve to mitigate or prevent common side effects of kidney cancer diagnosis, treatment, and survivorship. Further work will be done to study the benefit of exercise in a prospective manner in this population. Limitations include the inability to control for all comorbidities, the lack of granularity of disease staging and treatment data, and bias associated with retrospective studies. However, we believe our results are highly relevant to kidney cancer patients, those that care for them, as well as those who make financial decisions in our health care system.

Funding: N/A