Impact of neurocognitive deficits on patient-proxy agreement regarding health-related quality of life in low-grade glioma patients

Purpose Clinical trials in glioma patients with neurocognitive deficits face challenges due to lacking or unreliable patient self-reports on their health-related quality of life (HRQOL). Patient–proxy data could help solve this issue. We determined whether patient–proxy concordance levels were affected by patients’ neurocognitive functioning. Methods Patient and patient-by-proxy HRQOL ratings were assessed via SF-36 and EORTC QLQ-BN20, respectively, in 246 patients. Data on neurocognitive functioning were collected on a subgroup of 195 patients. Patient–proxy agreement was measured using the Bland–Altman limit of agreement, the mean difference, the concordance correlation coefficient (CCC), and the percentage difference (PD, ±0, 5, or 10 points). We defined patients to be cognitively impaired (n = 66) or cognitively intact (n = 129) based on their neurocognitive performance. Results Patients rated their physical function and general health to be better than their proxies did, while at the same time, patients reported more visual disorders, communication deficits, itchy skin, and problems with bladder control. The cognitively impaired subgroup reported poorer physical functioning, more visual disorders, headaches, itchy skin, and issues with bladder control. In the cognitively intact group, no statistical significant differences were observed between patients and proxies. Not surprisingly, Bland–Altman plots revealed a high agreement between the patient and patient-by-proxy rating in all HRQOL domains ranging from 95 to 99 %. The CCC was fairly high in all HRQOL domains (0.37–0.80), and the percentage of perfect agreement (PD ± 0) ranged from 8.5 to 76.8 %. In the cognitively impaired patients, the mean difference between patients and proxies was overall larger, and accordingly, agreement based on Bland–Altman plots was lower. Conclusions The level of agreement between patient and patient-by-proxy ratings of low-grade glioma patients’ HRQOL is generally high. However, patient–proxy agreement is lower in patients with neurocognitive deficits than in patients without neurocognitive deficits

Joint modeling of longitudinal health-related quality of life data and survival

In cancer research, outcome measures may co-vary. Treatment and treatment related impairment of health-related quality of life (HRQoL) may affect survival. When these effects are analyzed separately, bias may arise. Therefore, we investigated the combined effect of treatment and longitudinally measured HRQoL on survival. Patients with anaplastic oligodendrogliomas (n = 288) who were randomized (EORTC 26951) to radiotherapy (RT) alone or RT plus procarbazine, lomustine, and vincristine (PCV) chemotherapy were analyzed. HRQoL [appetite loss (AP)] was assessed with the EORTC QLQ-C30. We compared survival results from different analysis strategies: Cox model with treatment only [model 1 (M1)] or with treatment and time-dependent AP score [model 2 (M2)] and the joint model combining longitudinal AP score and survival [model 3 (M3)]. The estimated hazard ratio (HR) for RT plus PCV was 0.76 (95 % CI 0.58-1.00) for M1, 0.72 (0.55-0.96) for M2, and 0.69 (0.52-0.92) for M3. This corresponds to a lower risk of death of 24 % in M1, 28 % in M2, and 31 % in M3, for patients treated with RT plus PCV chemotherapy. AP resulted in an increased risk of death, with estimated HR of 1.06 (1.01-1.12) for M2 and 1.13 (1.03-1.23) for M3: Every 10-point increase of AP resulted in a 13 % increased risk of death in M3 as compared to 6 % in M2. Part of the survival benefit of treatment with RT plus PCV chemotherapy can be masked by the negative effect that this treatment has on patients' HRQoL. In our study, up to 7 % of the theoretical treatment efficacy was lost when AP was not adjusted through joint modeling

Quality of Life as a Prognostic Indicator of Survival: A Pooled Analysis of Individual Patient Data From Canadian Cancer Trials Group Clinical Trials

Neurolog

The Added Value of Analyzing Pooled Health-Related Quality of Life Data: A Review of the EORTC PROBE Initiative.

The European Organisation for Research and Treatment of Cancer (EORTC) Patient-Reported Outcomes and Behavioural Evidence (PROBE) initiative was established to investigate critical topics to better understand health-related quality of life (HRQOL) of cancer patients and to educate clinicians, policy makers, and healthcare providers.The aim of this paper is to review the major research outcomes of the pooled analysis of HRQOL data along with the clinical data. We identified 30 pooled EORTC randomized controlled trials (RCTs), 18 NCIC-Clinical Trials Group RCTs, and two German Ovarian Cancer Study Group RCTs, all using the EORTC QLQ-C30. All statistical tests were two-sided.Evidence was found that HRQOL data can offer prognostic information beyond clinical measures and improve prognostic accuracy in cancer RCTs (by 5.9%-8.3%). Moreover, models that considered both patient- and clinician-reported scores gained more prognostic overall survival accuracy for fatigue (P < .001), vomiting (P = .01), nausea (P < .001), and constipation (P = .01). Greater understanding of the association between symptom and/or functioning scales was developed by identifying physical, psychological, and gastrointestinal clusters. Additionally, minimally important differences in interpreting HRQOL changes for improvement and deterioration were found to vary across different patient populations and disease stages. Finally, HRQOL scores are statistically significantly affected by deviations from the intended time point at which the questionnaire is completed.The use of existing pooled data shows that it is possible to learn about general aspects of cancer HRQOL and methodology. Our work shows that setting up international pooled datasets holds great promise for understanding patients' unmet psychosocial needs and calls for additional empirical investigation to improve clinical care and understand cancer through retrospective HRQOL analyses

The Added Value of Analyzing Pooled Health-Related Quality of Life Data: A Review of the EORTC PROBE Initiative.

The European Organisation for Research and Treatment of Cancer (EORTC) Patient-Reported Outcomes and Behavioural Evidence (PROBE) initiative was established to investigate critical topics to better understand health-related quality of life (HRQOL) of cancer patients and to educate clinicians, policy makers, and healthcare providers.The aim of this paper is to review the major research outcomes of the pooled analysis of HRQOL data along with the clinical data. We identified 30 pooled EORTC randomized controlled trials (RCTs), 18 NCIC-Clinical Trials Group RCTs, and two German Ovarian Cancer Study Group RCTs, all using the EORTC QLQ-C30. All statistical tests were two-sided.Evidence was found that HRQOL data can offer prognostic information beyond clinical measures and improve prognostic accuracy in cancer RCTs (by 5.9%-8.3%). Moreover, models that considered both patient- and clinician-reported scores gained more prognostic overall survival accuracy for fatigue (P < .001), vomiting (P = .01), nausea (P < .001), and constipation (P = .01). Greater understanding of the association between symptom and/or functioning scales was developed by identifying physical, psychological, and gastrointestinal clusters. Additionally, minimally important differences in interpreting HRQOL changes for improvement and deterioration were found to vary across different patient populations and disease stages. Finally, HRQOL scores are statistically significantly affected by deviations from the intended time point at which the questionnaire is completed.The use of existing pooled data shows that it is possible to learn about general aspects of cancer HRQOL and methodology. Our work shows that setting up international pooled datasets holds great promise for understanding patients' unmet psychosocial needs and calls for additional empirical investigation to improve clinical care and understand cancer through retrospective HRQOL analyses