Multimethod Clinical Assessment of Patterns and Prevalence of Nonadherence (NA) to Imatinib Treatment (IMRx) in Patients (Pts) with Chronic Myeloid Leukemia (CML): Results from the ADAGIO Study.

BACKGROUND. ImRx for CML is a long-term treatment. Patterns and prevalence of NA to ImRx remain largely unknown. Short-term NA trends may be indicative of long-term NA. Methods for clinical NA assessment vary in reliability. A multimethod approach is indicated. OBJECTIVE. Multimethod estimation of patterns and prevalence of ImRx NA in CML pts at baseline (BL) and follow-up (FU) at 90 days (90d), incl. BL to 90d changes. DESIGN AND PATIENTS. Data subset from prospective, 90d observational, open-label, multicenter study. 169 evaluable pts on ImRx for minimum 30d at enrollment [[1][1]]. METHODS OF NA ASSESSMENT. At BL (NA with prior ImRx) and 90d (NA during study): visual analog scale (VAS) for physicians (phs; mVAS), pts (pVAS), cos (cVAS); Basel Assessment of Adherence Scale for pts (pBAAS; structured interview re NA in past 4 weeks [4wks]); pts reported persistence (pPST); % clinic appointments (%CAPPTS) kept (if any scheduled). At 90d also: % of ImRx taken per pill count (%pts@ImRx). RESULTS. See Table 1. CONCLUSIONS. Intuitive adherence ratings (VAS) by phs, pts, and cos are very high and differ from those from structured interview, where about one-third of patients exhibited NA behavior in 4wks prior to BL and FU - despite high persistence. Pill count suggests patterns of under- and overtaking, with only 1 out 7 patients being perfectly adherent. Rate of clinic appointments may be affected by physician scheduling practices and collateral input is a function of availability of collateral person. Consenting to participate in the ADAGIO study did not reduce NA. Though patient self-reports in structured interview (pBAAS) and pill counts have inherent biases, both indices suggest that NA with ImRx may be similar to NA rates in other disease categories. Especially pBAAS and pill count may be useful rapid clinical assessment tools, with pBAAS having the benefit of validated categorical assessment (vs. continuous in other methods). Determinants of NA and the impact of NA on treatment outcomes must be examined. | Method | | BL | 90d | | |:--------- | --- | --------------- | --------------------- | ----- | | | n | M±SD/Min-Max | M±SD/Min-Max | P | | mVAS | 164 | 95.0±7.6/60–100 | 94.9±9.9/0–100 | ns | | pVAS | 169 | 95.3±8.5/25–100 | 95.7±6.1/75–100 | ns | | cVAS | 56 | 97.1±5.1/80–100 | 97.4±5.1/75–100 | ns | | %pts@ImRx | 162 | - | 91.0±21.1/29.5–2002.2 | | | | | | 71.0% @ < 100% ImRx | | | | | | 14.2% @ 100% ImRx | | | | n | % NA | % NA | P | | pBAAS | 163 | 36.2% | 32.5% | ns | | %CAPPTS | 51 | 94.1% | 88.2% | 0.001 | | pPST | 163 | 98.8% | 100.0% | ns | Table 1 - Multimethod Assessment of Non-Adherence with Imatinib [1]: #ref-1