Cross-sectional and prospective studies of nutritional indices after percutaneous gastrostomy

Formal monitoring of nutritional status may be lacking in many patients after gastrostomy. We aimed to study nutritional assessment and its problems in patients after gastrostomy in a cross-sectional study, assess prospectively the changes in nutritional status of patients at 1 month and 6 months after gastrostomy placement, and determine the prognostic value of nutritional indices assessed at the time of gastrostomy placement.

We used cross-sectional and prospective cohorts. The subjects were institutional and community patients receiving percutaneous gastrostomy in a teaching hospital.

We studied patients living in the community and in long-term care institutions after gastrostomy. In the cross-sectional study, we observed all individuals who received a percutaneous gastrostomy from the Gastrointestinal Unit, Western General Hospital, Edinburgh from January 1994 to December 1996. In the prospective study, we observed consecutive referrals of patients to the Gastrointestinal Unit for percutaneous gastrostomy from March 1997 to June 1998. Nutritional status was assessed using: weight (kg), height or stature estimated from knee-height (m), mid-upper arm circumference and triceps skinfold thickness. Body mass index, arm-muscle circumference and corrected arm-muscle area were calculated. A blood sample was taken to assess micronutrient status.

In the cross-sectional study, 215 patients were identified who had received a percutaneous gastrostomy during the 3-year period 1994-1996. The weight and height measurements obtained in patients after gastrostomy were not as successful as upper-arm anthropometry. Of the 55 who were alive, traceable and agreed to take part in the study, 8% were under-nourished by corrected arm-muscle area at a median of 16 months after gastrostomy placement, whilst 57% had biochemical evidence of macro- or micronutrient deficiency. In the prospective study, 54 out of 87 patients referred for percutaneous gastrostomy agreed to participate. Using corrected arm-muscle area, 14% of patients were under-nourished at the time of gastrostomy placement. Changes in nutritional status at 1 month and 6 months post gastrostomy were mixed across the patient groups. Patients with a depleted corrected arm-muscle area 21.6 cm2 (log-rank test 9.05; P = 0.003, relative risk 4.7). All patients in whom corrected arm-muscle area had increased at the 1-month follow-up survived to 6 months post gastrostomy.

Assessment of nutritional status may be difficult in gastrostomy-fed patients. Upper-arm anthropometry is more often successful than other assessment methods and gives prognostic information.