Longitudinal Dynamic in Weight Loss Impacts Clinical Outcomes for Veterans Undergoing Curative Surgery for Colorectal Cancer
Background: Definitions of malnutrition imperfectly reflect nutritional status or predict perioperative consequences. We sought to identify predictive nutritional trends by examining the effect of preoperative weight on postoperative outcomes in patients with colorectal cancer (CRC).
Methods: This retrospective review examined 148 patients with CRC treated with curative-intent surgery at the Veterans Affairs Ann Arbor Healthcare System in Michigan from January 1, 2015 to December 31, 2019. We evaluated weight dynamics of patients, starting 1 year before cancer diagnosis until 1 year after surgery. We evaluated the association of these weight dynamics with surgical outcomes. Primary outcomes observed were hospital readmission and length of stay (LOS), chemotherapy completion, and delayed recovery defined as abnormal clinical developments.
Results: There were 115 patients in the colon cancer (CC) cohort and 33 in the rectal cancer (RC) cohort. Low preoperative albumin (< 3.5 g/dL) was present in 25 patients with CC (22%) and 11 patients with RC (33%). Six-month preoperative weight loss of at least 3% occurred in 32 patients with CC (36%). Delayed recovery was observed in 35 patients with CC (30%) and 21 patients with RC (64%). Nutrition consultation rates for the CC and RC groups were 15% and 36%, respectively, before the operation; 95% and 100%, respectively, for postoperative inpatients; and 12% and 73%, respectively, for postoperative outpatients. Six-month preoperative weight loss of ≥ 3% was significantly associated with delayed recovery (P < .001) and 60-day readmissions (P = .015) but not increased LOS or chemotherapy noncompletion.
Conclusions: A ≥ 3% weight loss 6 months preceding curative surgery for CRC was associated with adverse outcomes. An intensive nutrition prehabilitation program initiated at the time of cancer diagnosis is needed and may reduce associated complications.
Mean (SD) LOS was 6.4 (4.7) days (range, 1-28) for patients with CC and 8.8 (5.1) days (range, 3-23) for patients with RC. Mean (SD) LOS increased to 10.2 (4.3) days and 9.7 (6.0) days in patients with delayed recovery in the CC and RC cohorts, respectively. The mean (SD) LOS was 5.2 (2.8) days and 6.3 (2.2) days in patients without delayed recovery in the CC and RC cohorts, respectively. There was no significant difference when examining association between percent weight change and LOS for either initial admission (rs= -0.1409; 2-tailed P = .19) or for initial and readmission combined (rs = -0.13532; 2-tailed P = .21) within the CC cohort.
Chemotherapy
Within the CC cohort, 31 patients (27%) had an indication for adjuvant chemotherapy. Of these, 25 of 31 (81%) started chemotherapy within 12 weeks of surgical resection, and of these, 17 of 25 patients (68%) completed chemotherapy as indicated. Within the RC cohort all 33 patients had an indication for adjuvant chemotherapy, of these 18 of 33 patients (55%) began within 12 weeks of surgical resection, and 10 of 18 (56%) completed chemotherapy as indicated.
Among the CC cohort who began but did not complete adjuvant chemotherapy, there was no significant association between completion of chemotherapy and
Discussion
This study highlights several important findings. There were no patients in our cohort that met ASPEN malnourishment criteria with a BMI < 18.5. Twenty percent of patients lost at least 10 lb in 6 months before the operation. Notably, patients had significant associations with adverse outcomes with less pronounced weight loss than previously noted. As has been established previously, malnourishment can be difficult to screen for, and BMI also is often an imprecise tool.12 In the CC cohort, weight loss
Our findings imply that the effects of even mild malnutrition are even more profound than previously thought. Significantly, this applies to overweight and obese patients as well, as these constituted a significant fraction of our cohort. A finding of ≥ 3% weight loss at the time of CC diagnosis may provide an opportunity for a focused nutrition intervention up to the time of surgery. Second, although nutrition consultation was frequent in the inpatient setting during the hospital admission (96%-100%), rates of nutrition evaluation were as low as 15% before surgery and 12% after surgery, representing a key area for improvement and focused intervention. An optimal time for intervention and nutrition prehabilitation would be at time of diagnosis before surgery with plans for continued aggressive monitoring and subsequent follow-up. Our finding seems to provide a more sensitive tool to identify patients at risk for delayed recovery compared with the ASPEN-driven assessment. Given the simplicity and the clinical significance, our test consisting of 3% weight loss over 6 months, with its sensitivity of 57%, may be superior to the ASPEN 10-lb weight loss, with its sensitivity of 40% in our cohort.
