Post-bariatric Surgery Follow-up Found Inadequate, Putting Patients at Risk

Grace Halsey

UK investigators found guideline-recommended post-specialist care deficient, including low levels of nutrition monitoring and widely variable prescription of dietary supplements.

Patients who have undergone bariatric surgery may not be receiving adequate post-surgical care, placing them at risk for cardiovascular and neurologic conditions caused by nutritional deficiencies, concluded investigators in the United Kingdom.

Post-bariatric surgery guidelines from the UK National Institute for Health and Care Excellence (NICE) recommend that after weight-loss surgery, patients remain under the care of a specialist for 2 years and then continue follow-up with a general practitioner (GP). Further, patients should receive lifelong annual nutritional and weight monitoring under a shared care model between primary care and bariatric specialists, write authors led by Helen M. Parretti, MA, PhD, MSc, a consulting clinical senior lecturer at Norwich Medical School in the UK, in the British Journal of General Practice. They note, however, there is little support for GPs to commit to such long-term annual care.

Bariatric surgery is associated with significant health benefits, eg, remission of type 2 diabetes, improvements in cardiovascular disease and reduction in all cause mortality, observe the authors. But the surgery requires close follow up to avoid long-term risks including significant nutritional deficiencies and weight regain, the results of which can include "permanent disability or death in some cases."

Pointing to the absence of research on long-term care of these patients and the potential for patient harm related to poor monitoring, the researchers evaluated GPs adherence to the UK's post-bariatric surgery guidelines in the years following transition of care.

The retrospective cohort study drew participants from a UK electronic primary care database; cohort entry was restricted to adult patients (≥18 years) with BMI ≥30 kg/m2 before surgery and a record of bariatric surgery any time between Januarys 1, 2000 and January 1, 2015. Procedures of interest were laparoscopic adjustable gastric banding (LAGB), gastric bypass, and sleeve gastrectomy.

The primary outcome was an estimate of the annual proportion of patients with a record of weight measurement, recommended nutritional screening blood tests, and prescription of recommended nutritional supplements. A secondary aim was to examine the proportion of patients whose test result indicated a nutritional deficiency.

A total 3137 patients were eligible for inclusion; 20% were men; 52% white; mean age at surgery, 48.4 years. The mean BMI pre-surgery was 45.3 kg/m2 (SD 8.9) and mean BMI post-surgery was 36.8 kg/m2 (SD 8.8). Baseline characteristics were similar across bariatric procedures. Median follow-up post-surgery was 5.7 years (range 4.2-7.6) Distribution of procedures: LAGB 1400 (44.6%), gastric bypass 1067 (34.0%), sleeve gastrectomy 446 (14.3%), and other bariatric procedure 224 (7.1%).

RESULTS

Weight monitoring

Investigators found annual weight measurement in year 2-3 post surgery ranged from 59% for patients post-gastric bypass to 51% for those post-sleeve gastrectomy. Those percentages gradually declined for all procedures during years 3-4 and 4-5.

Nutritional monitoring blood tests

Measurement of nutritional monitoring blood tests recommended for LAGB varied between 29.7% for protein and 47.6% for creatinine in year 2–3 post-surgery, while 44.9% of patients had a hemoglobin (Hb) measurement in year 2–3 post-surgery. For gastric bypass and sleeve gastrectomy, differences in annual proportions of patients with measurement of a routinely requested blood test (eg, Hb, creatinine) and of a blood test specific to bariatric surgery differed markedly:

  • 59.7–64.2% had a record of creatinine measurement
  • 4.3–5.3% had measurements for zinc
  • 1.2–1.5% had measurements for copper

Nutritional deficiencies

Two deficiencies were most common: low hemoglobin, varying between 40.5% (sleeve gastrectomy) and 50.6% (gastric bypass and LAGB) of patients, and low ferritin, varying between 18.9% (LAGB) and 35.0% (gastric bypass and LAGB). Prescription of nutritional supplements recommended for patients after bariatric surgery also was extremely variable (see figure at left)

In their discussion, the authors state that their findings suggest that patients are not receiving the recommended nutritional care at the primary care level in terms of monitoring and treatment, placing them at increased risk of "preventable adverse outcomes.” They add that health care professionals and patients alike should understand the importance to long-term success of appropriate follow-up after bariatric surgery. Importantly, GPs should be supported to provide such care.