Primary care doctors currently face enormous patient demand for information about gluten-free diets and whether they might help with various states of health and illness. A fair number of those who ask have full-blown celiac disease (though most do not). The most often–quoted data point on US prevalence for the condition is 1 of 133 Americans in not-at-risk populations, so this is not an uncommon disease.1
The only effective treatment is complete avoidance of gluten, found in wheat-, barley-, and rye-containing products, which are nearly ubiquitous in US foods, but adherence to diet recommendations is known to be poor overall. An Australian study is the first randomized controlled trial testing the effectiveness of an online intervention in boosting adherence to a strictly gluten-free diet among patients with biopsy-proven celiac disease.2
The intervention (called “Bread n’ Butter . . . Gluten Free of Course!) is a 6-module educational program delivered online, with new 30-minute modules made available weekly. Module 1 was a required introduction, but subsequent modules did not have to be done in order and modules could be skipped without termination from the study. Content included some general information about celiac disease, but most modules focused on adherence techniques and communication skills based on cognitive-behavior therapy research.
Dietary adherence was measured by self-report with a previously validated instrument (the Celiac Dietary Adherence Test), performed at baseline, program completion, and 3 months after completion. Additional questionnaire material administered with adherence testing included scoring instruments for quality of life, depression, anxiety, stress, eating disorders, and knowledge of the condition. A total of 88 individuals were randomized to the control group, and 101 were randomized to the intervention.
There were no significant demographic, adherence, quality-of-life, or psychological variables between the groups at baseline. There was significant subject attrition in this study—only 50 intervention subjects and 64 control subjects completed the intervention and scoring processes (defined as completion of 4 or more modules). There were no significant differences between completers and non-completers on any of the baseline measurements.
The intervention group (completers) had significantly improved adherence scores from baseline to final measurement at 3 months, while the control group’s scores remained unchanged. There were no corresponding improvements in psychological symptoms.
Looking more closely at the data, the effect is clear but not overwhelming. At baseline, 39% of the intervention subjects had inadequate adherence. After the intervention, 34.6% remained in this category (11% of the inadequate adherers improved enough to be categorized as “adequate”).
Several limitations come to mind. This was a very short-term intervention and benefit may have been much larger in the setting of ongoing reminders over a longer period. One would certainly have liked to see follow-up measurements at 6, 12, and 24 months. Like obesity interventions designed to maximize the likelihood of weight loss at 1 year, we may see reversion to baseline behavior some months after completion of “Bread n’ Butter . . . Gluten Free of Course.” And the high attrition rate raises the possibility of unmeasured selection bias, despite similar baseline statistics for a handful of selected parameters. But the study validates the online mode of delivery as an effective means of promoting dietary adherence, and this may prove true across diets, so the study is relevant for the treatment of obesity, metabolic syndrome, and diabetes.
1. Fasano A, Berti I, Gerarduzzi T, et al. Prevalence of celiac disease in at-risk and not-at-risk groups in the United States—a large multicenter study. Arch Intern Med. 2003;163:286-292.
2. Sainsbury K, Mullan B, Sharpe L. A randomized controlled trial of an online intervention to improve gluten-free diet adherence in celiac disease. Am J Gastroenterol. 2013 Mar 5; [epub ahead of print]. doi:10.1038/ajg.2013.47