Patients with advanced colon cancer who drank 4 or more cups of coffee a day had 36% improved survival odds.
Higher levels of coffee drinking by patients with advanced or metastatic colorectal cancer (CRC) was linked with both overall survival (OS) and progression-free survival (PFS), according to a study published in JAMA Oncology.
The study analyzed 1171 patients and found that those who drank 4 or more cups of coffee a day had the best survival odds as well as slower disease progression.
The research looked at both caffeinated coffee and decaf; when analyzed apart, the association with PFS was stronger with caffeinated coffee, but both types were linked to OS.
Coffee may contribute to anticancer activity through various ways. Several compounds in coffee have antioxidant and anti-inflammatory effects. In addition, insulin resistance is believed to worsen CRC outcomes; coffee can sensitize tissues to the effects of insulin and decrease blood insulin levels.
While other studies have noted links to increased coffee consumption and decreased recurrence and deaths from colon cancer, the association between drinking coffee and survival in patients with advanced or metastatic disease is unknown.
The patients were queried about their diet as an option included in a phase 3 clinical trial comparing the addition of cetuximab and/or bevacizumab to standard chemotherapy. They answered a semiquantitative food frequency questionnaire within the first month of enrollment and from 2005 to early 2018.
Of the 1171 patients, 694 were men (59%) with a median age of 59; 86% of the participants were White. A multivariable model controlled for additional factors known or suspected to affect survival in patients with CRC.
The median follow-up time among living patients was 5.4 years (10th percentile, 1.3 years; interquartile range [IQR] was 3.2 to 6.3 years. A total of 1092 patients (93%) had died or had disease progression.
The results showed that higher levels of coffee drinking, as measured by cups per day, was associated with a decreased risk of cancer progression (HR for 1-cup/d increment, 0.95; 95% CI, 0.91-1.00; P = .04 for trend) and death (HR for 1-cup/d increment, 0.93; 95% CI, 0.89-0.98; P = .004 for trend).
Compared with those who did not drink coffee, the multivariable analysis showed that drinking at least 4 cups of coffee per day led to a 36% increased chance of improved OS (HR, 0.64; 95% CI, 0.46-0.87) and 22% increased odd of better PFS (HR, 0.78; 95% CI, 0.59-1.05).
Drinking 2 to 3 cups of coffee per day had the same results for both OS (HR, 0.82; 95% CI, 0.67-1.00) and PFS (HR, 0.82; 95% CI, 0.68-0.99).
At least 2 cups per day of decaf had a positive result as well for both OS (HR, 0.64; 95% CI, 0.43-0.95; P = .003 for trend) and PFS (HR, 0.75; 95% CI, 0.52-1.09; P = .05 for trend).
Although the authors said it is the first study to find a protective effect of coffee in metastatic CRC, several things about the association remain unknown. For instance, the majority of people who drink coffee during cancer treatment likely drank it before their diagnosis, so a question remains as to whether coffee drinkers tend to develop less aggressive disease, or if coffee exerts an effect on active tumors.
Mackintosh C, Yuan C, Ou FS, et al. Association of coffee intake with survival in patients with advanced or metastatic colorectal cancer. JAMA Oncol. Published online September 17, 2020. doi:10.1001/jamaoncol.2020.3938