Comorbidities and sex differences in causes of death among mantle cell lymphoma patients – A nationwide population‐based cohort study

Summary The prognosis for mantle cell lymphoma (MCL) remains poor. Our aim was to assess the impact of comorbidities on survival and causes of death. For 1,385 MCL patients (1,009 males, 376 females) diagnosed in 2000–2014 (median age 71 years, range 22–96) comorbidities ≤ 10 years of diagnosis were classified according to the Charlson comorbidity index (CCI; 0, 1, 2+). Hazard ratios (HRs) with 95% confidence intervals (CIs) were estimated to compare lymphoma‐specific and all‐cause mortality rates. Model‐based predictions were used to obtain probabilities of death. Overall, 44% had any comorbidity (CCI 1+) and 28% severe comorbidity (CCI 2+). Over a median follow‐up of 3·7 years (range 0–16), 633 (46%) died, the majority (76%) from lymphoma. Severe comorbidity was independently associated with higher all‐cause [hazard ratio (HR) = 1·52; 95% CI: 1·24–1·85) and lymphoma‐specific mortality (HR = 1·31; 95% CI: 1·04–1·65). Particularly among patients with connective tissue, renal and psychiatric diseases, and dementia. Among females with any comorbidity, non‐lymphoma deaths represented a larger proportion of all deaths, compared to males with any comorbidity. In general, more efficient lymphoma treatments need to be considered also for patients with severe comorbidity. However, among females with any comorbidity, the likelihood of non‐lymphoma death was still considerable, perhaps favouring a more liberal use of a “wait and watch” approach.