Trajectories of health-related quality of life after cancer diagnosis in a cohort of Australian women: A longitudinal study

Background With increasing cancer survival rates, optimising health-related quality of life (HRQL) has become a major priority. However, longitudinal assessments of HRQL outcomes in people with cancer are limited. We aimed to examine the changes in HRQL after a cancer diagnosis and identify the long-term trajectories of HRQL outcomes and associated factors. Methods This study included 1414 women diagnosed with primary invasive cancer from 1996 to 2019 and 2828 women without cancer from a large cohort (born in 1946-51) of the Australian Longitudinal Study on Women’s Health, linked to the Australian Cancer Database. Generalised linear models were used to estimate changes in HRQL outcomes, adjusting for sociodemographic factors and other health conditions. Group-based multitrajectory modelling was applied to identify HRQL trajectories over time. Results In the short-term (≤ 3 years), we found a significant decline in the adjusted mean difference (AMD) across all HRQL domains at post-cancer versus pre-cancer survey, with the largest decline in general health (AMD − 10.3, 95%CI: -11.43, -9.18). The corresponding changes within the same period among women without cancer were not significant at p < 0.05, except for physical functioning. In the long-term (≤ 15 years), four HRQL trajectory groups were identified, including very low HRQL trajectory (n = 184, 13%), moderate HRQL trajectory (n = 355, 25%), medium-high HRQL trajectory (n = 532, 38%) and high HRQL trajectory (n = 343, 24%). In the control sample, a greater proportion of women belonged to the high HRQL trajectory group (29% versus 24%). Cancer survivors in the very low or moderate HRQL trajectory groups had significantly lower HRQL scores than the corresponding trajectory groups in the control group ( p  < 0.05). Compared with the high HRQL trajectory group, the very low HRQL trajectory group experienced more difficulties in managing their available income (60% versus 22%, p < 0.01) and had ≥ 2 comorbidities (42% versus 9%, p < 0.01). Conclusions Our findings suggest the importance of measuring HRQL soon after diagnosis as a baseline measure, and considering both baseline and ongoing HRQL when guiding supportive care for women cancer survivors. Additionally, targeted initiatives that prevent and manage comorbidities and financial hardship in those with low HRQL at baseline are critical for equitable care.