Phenotypic and molecular characteristics associated with various domains of quality of life in oncology patients and their family caregivers

Abstract

Purpose: Not all oncology patients and their family caregivers (FCs) experience the same quality of life (QOL). The purposes of this study were to identify latent classes of oncology patients (n = 168) and their FCs (n = 85) with distinct physical, psychological, social, and spiritual well-being trajectories from prior to through 4 months after the completion of radiation therapy and to evaluate for demographic, clinical, and genetic characteristics that distinguished between these latent classes.

Methods: Using growth mixture modeling, two latent classes were found for three (i.e., physical, psychological, and social well-being) of the four QOL domains evaluated.

Results: Across these three domains, the largest percentage of participants reported relatively high well-being scores across the 6 months of the study. Across these three QOL domains, patients and FCs who were younger, female, belonged to an ethnic minority group, had children at home, had multiple comorbid conditions, or had a lower functional status, were more likely to be classified in the lower QOL class. The social well-being domain was the only domain that had a polymorphism in nuclear factor kappa beta 2 (NFKB2) associated with latent class membership. Carrying one or two doses of the rare allele for rs7897947 was associated with a 54 % decrease in the odds of belonging to the lower social well-being class [OR (95 % CI) = .46 (.21, .99), p = .049].

Conclusions: These findings suggest that a number of phenotypic and molecular characteristics contribute to differences in QOL in oncology patients and their FCs.

Keywords: Cytokines; Family caregivers; Genetics; Growth mixture modeling; Oncology; Quality of life; Radiation therapy.

Figure 1

A - Observed and estimated physical well-being domain trajectories for participants in each of the latent classes. B - Observed and estimated psychological well-being domain trajectories for participants in each of the latent classes. C - Observed and estimated social well-being domain trajectories for participants in each of the latent classes. D - Observed and estimated spiritual well-being domain trajectory for participants in the latent class.

Figure 2

Differences between the social well-being latent classes in the percentages of participants who were homozygous for the common T allele (TT), or heterozygous or homozygous for the rare G allele (TG + GG) for rs7897947 in nuclear factor kappa beta 2 (NFKB2).