Diabetes status modifies the efficacy of home-based kidney care for Zuni Indians in a randomized controlled trial

Home-Based Kidney Care (HBKC) is a pragmatic treatment approach that addresses patient preferences and cultural barriers to healthcare. We previously reported the results of a clinical trial of HBKC vs. usual care in a cohort of Zuni Indians in New Mexico. This study investigated the potential for differential efficacy of HBKC vs. usual care according to type 2 diabetes (T2DM) status.

We analyzed the data from all individuals who participated in a randomized clinical trial that compared HBKC to usual care among patients with CKD, and assessed whether the effect of the HBKC intervention affected the subset of patients with T2DM differently than those individuals without T2DM. We used linear regression models to estimate the effect of HBKC on improvement in Patient Activation Measure (PAM) total scores within the groups of participants defined by T2DM status, and to compare the effects between these two groups. We used generalized estimating equations (GEE) to account for household clustering.

The original study enrolled 63 participants into the HBKC group, and 62 into the usual care. Ninety-eight of these individuals completed the 12-month intervention, 50 in the HBKC group and 48 in the usual care group. The present study compared the intervention effect in the 56 participants with T2DM (24 participants in the HBKC group and 32 in usual care) to the intervention effect in the 42 participants without T2DM (26 participants in the HBKC group and 16 in usual care). Those with T2DM who received the HBKC intervention experienced an average increase in PAM total scores of 16.0 points (95% Confidence Interval: 8.8-23.1) more than those with T2DM who were in the usual care group. For those without T2DM, the intervention had essentially no effect, with those who received the HBKC intervention having an average PAM total scores that was 1.4 points (95% C.I.: -12.4 to 9.6) lower than those who received usual care. There was a significantly different HBKC treatment effect by T2DM status (p = 0.02).

This secondary analysis suggests that the effectiveness of this HBKC intervention on increasing patient activation is most notable among those CKD patients who also have T2DM.