Increased risk for psychiatric disorders is faced by spouses of patients with cancer, according to study findings published in the JAMA Network Open.
Investigators sought to evaluate the extent of psychiatric disorders among spouses of patients with cancer vs spouses of individuals without cancer, and possible changes over time with this burden, testing the hypotheses that spouses of patients with cancer face an increased risk for psychiatric disorders vs spouses of individuals without cancer, and risk is most pronounced immediately after cancer diagnosis.
They conducted a population-based cohort study that included 546,321 spouses of patients with cancer (exposed group; diagnosed in Denmark 1986-2016, diagnosed in Sweden 1973-2014) and 2,731,534 spouses of individuals without cancer (unexposed group) identified through various Danish and Swedish public registers without specific inclusion or exclusion criteria. Individuals in the unexposed groups were well-matched to individuals in the exposed group for sex, age, and country.
Analysis was performed between May 2021 and January 2022. Individuals who had been exposed (had a spouse with cancer) or a diagnosis of psychiatric disorders before the start of follow-up were excluded. Follow-up ended December 2016 in Denmark and December 2014 in Sweden. Danish residents represented more than 70% of all participants. Danish spouses were more likely to be older, women, and have lower education and income than Swedish spouses.
Overall, 54.0% were women, median age at cohort entry 60 years (IQR 51 to 68 years), and in follow-up (median, 8.4 years exposed vs 7.6 years unexposed) the incidence rate per 1000 person-years of first-onset psychiatric disorders was 6.8 exposed vs 5.9 unexposed (6.9% of spouses of patients with cancer vs 5.6% of spouses of individuals without cancer).
Investigators noted that during the first year after cancer diagnosis, the risk for first-onset psychiatric disorders increased by 30% (adjusted hazard ratio [HR], 1.30; 95% CI, 1.25-1.34), risk for depression (adjusted HR, 1.38; 95% CI, 1.30-1.47), and risk for stress-related disorders (adjust HR, 2.04; 95% CI, 1.88-2.22).
They noted during the entire follow-up, the risk for first-onset psychiatric disorders increased by 14% (adjusted HR, 1.14; 95% CI, 1.13-1.16), similar for depression, stress-related disorders, and substance abuse. Risk increase was most prominent among spouses of patients at an advanced stage of cancer (adjusted HR, 1.31; 95% CI, 1.26-1.36) or with a poor cancer prognosis (pancreatic cancer: adjusted HR, 1.41; 95% CI, 1.32-1.51). The risk was also prominent when the patient died during follow-up (adjusted HR, 1.29; 95% CI, 1.27-1.31).
Investigators found that during the entire follow-up, for spouses with preexisting psychiatric morbidity (analyzed separately from those without preexisting morbidity), the risk for first-onset or recurrent psychiatric disorders increased by 23% (adjusted HR, 1.23; 95% CI, 1.20-1.25). They noted men and individuals aged 40 to 59 years and 60 to 79 years had a slightly greater risk increase of first-onset psychiatric disorders when exposed to a spousal cancer diagnosis vs their counterparts (women and individuals in other age groups).
In their cohort study of 2 populations in Denmark and Sweden, investigators concluded, “Spouses of patients with cancer showed an increased risk of psychiatric disorders requiring secondary care, both immediately after cancer diagnosis and during the decades thereafter.” They wrote, “The risk increase was greater during the first year after cancer diagnosis, for fatal cancer, among male spouses, and among spouses with preexisting psychiatric morbidity.” They urge clinical awareness especially in these high-risk groups to prevent potential mental illness among the spouses of patients with cancer.
Hu K, Liu Q, László KD, et al. Risk of psychiatric disorders among spouses of patients with cancer in Denmark and Sweden. JAMA Netw Open. Published online January 5, 2023. doi:10.1001/jamanetworkopen.2022.49560