Impaired Sleep Influences Health Care Related Quality of Life in Patients With Well Differentiated Thyroid Carcinoma

Background: Most patients with well differentiated thyroid carcinoma (WDTC) have a favorable prognosis but often report lower health care related quality of life (HRQoL). Sleep quality is one contributor to HRQoL that has also been reported to be impaired in WDTC patients. We evaluated patient reported outcome measures (PROM) of HRQoL and sleep quality in patients with WDTC, and compared them to patients with thyroid nodules. Methods: This is a single institution cohort study utilizing data on consented adult patients with WDTC or thyroid nodules from an integrated cancer research database. We included participants with WDTC and thyroid nodules who completed the SF-36v2 HRQoL survey and the Pittsburgh Sleep Quality Index (PSQI). HRQoL was reported as a composite mental (MCS) and physical (PCS) component score that was compared with population-based norms and reported as the frequency of patients scoring below or well below the age-controlled reference population. Sleep quality was reported as PSQI raw score. Poor sleep quality was defined as a PSQI score >5. Cancer stage was calculated as American Joint Commission on Cancer (AJCC) 7(th) and 8(th) edition for each subject in the registry. Results: We evaluated 727 patients and 424 (58%) had WDTC: 219 (72%) with papillary thyroid carcinoma (PTC), 28 (9%) with follicular variant of PTC, 53 (18%) with follicular thyroid carcinoma and 3 (1%) with Hurthle cell carcinoma. Of these, 208 (68.7%) were treated with radioactive iodine ablation with a mean cumulative dose of 197.7 (range 29-700) mCi. Mean age for WDTC was 42.7 years (standard deviation SD 15.4), and 53.4 years (SD 14.3) for nodules (p < 0.001). Eighty one percent of WDTC and 368 (87%) of nodules were female (p = 0.022). PSQI indicated worse sleep quality for WDTC patients with a mean of 6.85 (SD 3.97) and 174 (57.4%) reporting poor sleep quality with a PSQI > 5, compared with a mean score of 6.8 (SD 4.05) and 170 (40.1%) with PSQI > 5 for nodules (p < 0.001). WDTC diagnosis was associated with poor sleep quality with an odds ratio of 2.02 (95% confidence interval 1.48 - 2.75), p < 0.001. Poor quality sleep was also associated with WDTC stage using AJCC8 (0.017) but not AJCC7 (p = 0.067). Overall PCS, MCS, and HRQoL category were not significantly different between WDTC and nodule groups. When stratified by stage, MCS was inversely associated with cancer stage using AJCC7 (p = 0.035) but not AJCC8 (p = 0.96); PCS was associated with cancer stage using both AJCC7 (p = 0.003) and AJCC8 (p < 0.001). Conclusions: Patients with WDTC report worse sleep quality than those with thyroid nodules and it is correlated with AJCC8 stage. HRQoL is similar between all WDTC patients and those with thyroid nodules in this cohort, though WDTC patients with higher stage reported worse physical function. The AJCC 8th was more sensitive to differences in sleep quality and physical function by stage than AJCC 7th.