br ADL score br PCS score
Abbreviations: ADL, activities of daily living; IQR, interquartile range; MCS, mental component summary; PCS, physical component sum-mary; SD, standard deviation.
* P values for continuous and categorical variables are from the Wilcoxon rank sum test and chi-square test, respectively; they represent comparisons between the noncancer patients and each treatment group separately (ie, noncancer controls vs conservative management, noncancer controls vs surgery, noncancer controls vs radiation).
** Exact numbers not shown in compliance with SEER-MHOS guidelines. *** Missing data includes marital status (280 noncancer, 44 conservative management, <11 surgery, 15 radiation), education (437 non-cancer, <11 conservative management, <11 radiation), and household income (5785 noncancer, 27 conservative management, <11 sur-gery, 29 radiation). Missing values were imputed in subsequent analyses.
who underwent surgery, radiation, or active surveillance.4 Yet, there are also studies that demonstrate that even 1-point lower PCS and MCS scores are associated with signifi-cant increased risks of hospitalization and mortality.25
Regardless, the findings in this study have important implications. While studies have examined disease-specific functional outcomes among prostate cancer patients,26 few have assessed general functional status.7 This study is unique in that it examines general functional status among a cohort of Medicare Advantage beneficiaries during a time in which
several new surgical and 2NBDG technologies emerged. The observation that surgery patients showed no difference in ADL scores but a decline in PCS scores raises the ques-tion of whether more granular measurements of physical function may improve the evaluation of general functional status in this population. For example, the Nagi scale con-tains 12 questions about physical function, including inqui-ries about difficulty lifting objects as heavy as ten pounds and difficulty standing for long periods, which are not assessed as part of the PCS score.27
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Figure 1. Changes* in ADL (A), PCS (B) and MCS (C) scores among patients undergoing conservative management and their matched noncancer peers*Changes are based on 2 surveys: one prior to conservative management and one after conserva-tive management. In the matched noncancer group, the time interval between the 2 surveys is matched with that of the treated patients. Compared with matched noncancer patients, conservative management patients experienced no differen-ces in ADL, PCS, or MCS scores over time (all P > 0.05). The P value is testing if the change in the outcome (ADL, PCS, or MCS) from before to after differs by treatment. A positive slope represents a decline in functional status for ADL’s and an improvement in functional status for PCS and MCS scores. Some confidence intervals are too small to be seen in figure. Abbreviations: ADL, activities of daily living; MCS, mental component summary; PCS, physical component summary.
Our findings should be interpreted in the context of sev-eral limitations. First, we used a dataset that only contained information about Medicare Advantage beneficiaries. These beneficiaries may represent healthier individuals,28
and thus, our findings may not be generalizable to the Medicare fee-for-service population. However, the superior health of Medicare Advantage beneficiaries may be overes-timated.29 Regardless, the number of Medicare Advantage
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Figure 2. Changes* in ADL (A), PCS (B) and MCS (C) scores among patients undergoing surgery and their matched non-cancer peers.*Changes are based on 2 surveys. For the surgery patients, one survey is prior to surgery and one survey is after surgery. In the matched noncancer group, the time interval between the 2 surveys is matched with that of the surgery patients. Compared with matched noncancer patients, surgery patients experienced no differences in ADL scores over time (P = 0.96). Surgery patients did show a decline in PCS (adjusted mean difference = 4.5, P < 0.001) and MCS (adjusted mean difference = 3.3, P = 0.01) scores. The P value is testing if the change in the outcome (ADL, PCS, or MCS) from before to after differs by treatment. A positive slope represents a decline in functional status for ADL’s and an improvement in func-tional status for PCS and MCS scores. Some confidence intervals are too small to be seen in figure. Abbreviations: ADL, activities of daily living; MCS, mental component summary; PCS, physical component summary
beneficiaries in the United States is increasing (as high as 25% of the Medicare population during the study period)30 and few opportunities exist to examine the health of this population on a national level.
Second, since we required patients to have a survey before and after treatment, the number of patients receiving