Epidemiology of inflammatory bowel diseases in the elderly in the province of Liège.

OBJECTIVE: Inflammatory bowel diseases (IBD) are heterogeneous diseases which affect preferentially young adults. The late onset could represent a particular form of expression of these diseases. The aim of our prospective study was to describe the incidence of IBD in patients older than 60 years as well as their clinical pattern in comparison with a population younger than 60. METHODS: A standardized questionnaire for each new case diagnosed in the province of Liège between 01/06/1993 and 31/05/1996 was completed. RESULTS: During the three years, 270 patients were enrolled. In group IBD > 60 years old, there were 60 new cases, including 23 cases with Crohn's disease (CD) (38%), 30 with ulcerative colitis (UC) (50%), and 7 with undetermined colitis (IC) (12%). The proportion of CD was significantly lower in the group IBD > 60 years old than in the group<60 (114 CD (54%), 81 UC (39%) and 15 IC (7%); P=0.04). The annual incidence tended to be higher for UC than for CD in group IBD > 60 (4.5 and 3.5 per 100,000, respectively) while it was the contrary in younger patients (3.4 and 4.8 per 100,000, respectively). There was no striking difference in the clinical features for both diseases in the two groups, except more frequent diarrhea, weight loss and extraintestinal symptoms in CD patients<60 years old. CONCLUSIONS: In the province of Liège, the incidence of IBD in people older than 60 years is high. IBD in the elderly is characterized by a lower proportion of CD than in the younger population. Clinical features tend to be the same whatever the age at diagnosis for each disease.

Magnesium wasting associated with epidermal-growth-factor receptor-targeting antibodies in colorectal cancer: a prospective study.

BACKGROUND: Preliminary evidence suggests that magnesium wasting occurs in patients who are treated with epidermal-growth-factor receptor (EGFR)-targeting antibodies for colorectal cancer. The mechanism of this side-effect is unknown, and if all or a subset of patients are affected is also unclear. We aimed to assess the incidence, characteristics, and predictive factors of magnesium wasting during treatment with EGFR-targeting antibodies, and to study the pathophysiology of this phenomenon. METHODS: We measured prospectively magnesium concentrations in a cohort of 98 patients with colorectal cancer treated with EGFR-targeting antibodies with or without combined chemotherapy. The primary outcome measure was the slope of the serum magnesium concentrations over time. In 35 patients, 24-h urinary magnesium excretion was measured. In a subset of patients (n=5), an intravenous magnesium load test was done. 16 patients who had chemotherapy alone acted as controls. A clinical protocol was written before initiation of the study, but because this was a non-interventional study, the protocol was not formally registered. FINDINGS: 95 (97%) patients had decreasing serum magnesium concentrations during EGFR-targeting treatment compared with baseline measurements. The mean serum magnesium slope during EGFR-targeting treatment (with or without combined chemotherapy) was significantly lower compared with chemotherapy alone (-0.00157 mmol/L/day, SD 0.00162 [95% CI -0.00191 to -0.00123] vs 0.00014 mmol/L/day, SD -00076 [-0.00026 to 0.00055]; (t test, p < 0.0001). 24-h urine analysis and intravenous magnesium load tests showed a defect in renal magnesium reabsorption. INTERPRETATION: EGFR-inhibiting antibodies compromised the renal magnesium retention capacity, leading to hypomagnesaemia in most patients. Future studies should address the effects of exposure and target affinity. Our study suggests a pivotal role of the EGFR-signalling pathway in regulating magnesium homoeostasis.