Background

Patients undergoing bariatric surgery are at an increased risk of developing micronutrient deficiency [1] through a combination of pre-existing deficiency [2], decreased post-operative intake [3], and reduced absorption [4]. Patients are therefore advised lifelong micronutrient supplementation [5, 6]. However, adherence to these recommendations can be poor [7,8,9].

Poor adherence to micronutrient supplementation after bariatric surgery is associated with higher rates of micronutrient deficiency [7, 10, 11] and can result in a range of nutritional complications [12] including anaemia, bone loss, or even neurological problems. It is therefore important to understand the reasons behind poor adherence with post-bariatric surgery nutritional supplementation guidelines.

There are very few studies [7, 9] in the scientific literature specifically attempting to understand the factors associated with poor compliance with micronutrient supplementation recommendations after bariatric surgery. Overall tablet burden, need to take them at different times through the day, side effects, cost, and behavioural factors might be some of the important underlying factors, but there is no robust scientific proof to conclude this. Studies examining interventions aimed at improving the compliance rates are even fewer [13], and there is none that attempts to understand patients’ perspectives on this topic. To the best of our knowledge, there is no published data on why patients find it difficult to adhere to recommended regimes and their thoughts on how it could be addressed.

The purpose of this study was to find outpatient reported knowledge and adherence to supplementation protocols after bariatric surgery and seek their perspectives on the reasons behind poor adherence and how to improve it.

Methods

Bariatric surgery patients living in the UK were invited to participate in a questionnaire (Appendix 1) designed to understand adherence to nutritional recommendations after bariatric surgery and patient perspectives on how it could be improved. We decided to only include patients living in the UK as some of the reasons behind poor compliance can be specific to the population and healthcare delivery systems.

Inclusion Criteria

We included all patients who had undergone a bariatric procedure and were living in the UK at the time of the study irrespective of where the bariatric procedure was carried out as some patients go abroad for a bariatric procedure.

Exclusion Criteria

Exclusion criteria were patients who have not had a bariatric procedure and those who were not living in the UK.

Study Design

An anonymous questionnaire-based survey was designed on SurveyMonkey® to capture important information about patient demographics, nutritional supplementation compliance status, and reasons behind poor compliance. We also sought patients’ opinion on how compliance with post-bariatric surgery supplements could be improved. The survey was made live on 7 May 2018. The survey link was freely shared on social media and amongst patient support groups. The survey was closed for analysis on 23 May 2018.

Statistics

Basic descriptive statistics were used. Categorical variables were compared using Fisher’s exact test on GraphPad®. Two-tailed p value was used.

Results

We obtained a total of 533 responses. After excluding those not currently living in the UK (n = 1) and those who had not undergone bariatric surgery yet (n = 3), we were left with responses of 529 post-bariatric surgery patients living in the UK. Out of these, 63.0% (n = 333) had undergone a Roux-en-Y gastric bypass (RYGB), 24.0% (n = 129) had undergone a sleeve gastrectomy (SG), 7.0% had undergone a gastric band (n = 37), and 5.7% (n = 30) had undergone a one anastomosis (mini) gastric bypass (OAGB).

Majority of the respondents (92.61%, n = 489) were females. Most of the patients were either in full-time (49.0%, n = 260) or part-time (15.7%, n = 83) employment. Approximately 10.0% (n = 54) were retired, and 4.7% (n = 25/529) were unemployed. A little over 13.0% (n = 69) patients described themselves as disabled. The mean age of the patients was 47.7 (range 22–73, median 48) years.

Tables 1, 2, and 3 show data on whether patients were recommended any lifelong supplements and if they knew which supplements to take and the exact amount they needed to take. Significantly, nearly 6.0% (n = 32; 27.0% bypass, 11.5% sleeves, and 61.5% bands) said that they had not been recommended lifelong supplements or were unsure about it.

Table 1 Patients’ response on if their bariatric teams have recommended any lifelong mineral/vitamin supplementation
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Table 2 Patients’ response on if they knew which supplements to take
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Table 3 Patients’ response on if they knew the exact amount of each supplement they need to take
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Table 4 shows patient-reported compliance with post-bariatric surgery nutritional supplements.

Table 4 Patient-reported compliance with post-bariatric surgery nutritional supplements
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Slightly over half (54.2%, n = 287) of the respondents reported having trouble taking all their supplements. Approximately, 45.5% patients [65.0% males vs 44.0% females; p value 0.016] reported complete compliance. Approximately 42.0% (n = 109) patients in full-time employment reported complete compliance compared to 48.6% of the rest (129) (p value 0.13).

Table 5 lists the reasons behind non-compliance. Amongst the other reasons reported, commonest were difficulty in swallowing the tablets because of the size, complacency, advice from GP that they do not need them, too many tablets, need to take them several times a day, or being “fed up”. When asked what would make it easier for them to take supplements, patients provided with a number of thoughts. Table 6 lists these thoughts. Amongst other thoughts, patients suggested having a national guideline to standardise protocols, educating primary care healthcare professionals, blister packs for medicines, smaller tablets, give them as injections weekly or monthly, reminder app, make them tastier, a “one-stop tablet”, liquid form, take them all at the same time, more chewable options, dissolvable, a patch, less side effects, and post-surgery psychology support.

Table 5 Patient-reported reasons for difficulty in adhering to nutritional supplements post-bariatric surgery
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Table 6 Patients’ thoughts on what would make it easier for them to take supplements
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When asked to name the preparations they find most difficult to take, 79 patients mentioned Forceval® tablet (15.0%), 28 (5.3%) mentioned other multivitamin preparations, 40 mentioned iron preparations (7.5%), 30 mentioned Adcal® (5.67%), and 52 (9.8%) mentioned other calcium or vitamin D preparations, and 6 (1.1%) found vitamin B12 injections difficult.

Discussion

Majority of the respondents in this survey had undergone an RYGB in keeping with the last report of the UK National Bariatric Surgery Report [14] where RYGB was reported to be the more common bariatric procedure in the British practice. In keeping with other published data on bariatric surgery, the majority of the patients were females.

As expected, most (94.0%) of the respondents in this survey acknowledged that they had been recommended lifelong micronutrient supplementation. Somewhat alarmingly, 6.0% reported that they had not been recommended or were not sure about it. Data on compliance (Table 4) was, even more, worrying with only 45.5% of patients reporting complete compliance. Interestingly, 65.0% (24/37) of the male patient reported complete compliance compared with 44.0% of females. This is different to study by Sunil et al. [7] where male sex was found to be significantly associated with non-adherence. But similar to Sunil et al. [7], patients in full-time employment reported lower complete compliance (the difference was not statistically significant).

The most important reported reason for poor compliance was difficulty in remembering (45.6%), followed by too many tablets (16.4%), side effects (14.3%), cost (11.5%), non-prescribing by GP (10.8%), bad taste (10.1%), and not feeling the need to take it (9.4%).

Since the most common reported reason for poor compliance was difficulty in remembering them (45.6%), it should be possible to use the modern technology to at least partially overcome this problem. There are apps out there to support bariatric surgery patients, but most of them have been designed without adequate patient and professional input [15] and are, therefore, unsuitable for purpose. Any suitable bariatric app should be able to answer common patient queries, provide advice for common symptoms and complications after bariatric surgery, record patients’ weight loss journey, remind patients to take supplements daily, and remind them to contact their general practitioners for blood tests when at the time of the anniversary of their procedure. Healthcare teams, on their part, should explore ways to offer more virtual clinics without the need for physical attendance by the patients [16].

Approximately 16.4% of patients in this study cited too many tablets as one of the factors behind poor compliance and a significant 41.8% of patients in this study suggested reducing the number of tablets. Since calcium can interfere with iron absorption [10], it may not be possible to combine all micronutrients into one tablet. Future studies do however need to examine if it is possible to reduce the overall number of tablets that the patients are required to take. Side effect and bad taste were cited as reasons behind poor compliance by 14.3% and 10.1% of the patients respectively. It would be worth finding out if altering the formulation could be of help in such situations. For example, liquid or chewable preparations might help patients struggling with large tablets that need swallowing [17].

Cost, mentioned by 11.5% of our patients, is probably an even bigger issue in healthcare systems funded privately. But the cost of the supplements should be balanced against the cost of managing the nutritional deficiencies which will inevitably develop. Patients should be educated about this and informed of the additional financial burden prior to the surgery. It may also be possible to look for cheaper non-branded alternatives [18].

Non-prescribing by GP was mentioned as a reason behind poor compliance by 10.8% of the patients. Previous studies have shown that there is a knowledge gap amongst primary care physicians when it comes to looking after patients who have had bariatric surgery [19]. Bariatric societies around the world need to develop closer links with primary care to address this.

Significantly, 9.4% of the patients did not feel the need to take their supplements, and approximately a quarter of the patients (25.7%) emphasised the importance of patient education. In a recent study, Lier et al. [13] found that preoperative counselling did not improve adherence to treatment guidelines in patients who underwent bariatric surgery. Authors suggested that such interventions might be more useful after surgery. Patient organisations and support groups can help bridge the education gap with the help of professionals.

There are several weaknesses to this study. First of all, the data on compliance is patient reported and not measured objectively. This is, however, a general problem with bariatric literature. In a recent review, Hood et al. [20] found that the majority of studies have used self-reported data on vitamin use adherence after bariatric surgery.

Secondly, we only studied patients living in the UK as some of the reasons for poor compliance, like non-prescribing by general practitioners, may not be applicable universally. However, authors believe that most of the themes outlined in this study are generally applicable to different population groups and this study can pave way for future examinations in different population groups. Third, because of the nature of our study design when the survey link was freely shared on social media, we cannot provide an accurate response rate and may have precluded patients not well versed with social media and Internet. The possibility of some selection bias, therefore, has to be acknowledged. However, we believe that a survey of 529 patients is likely to have captured most of the opinions on this topic as one of our main objectives was to understand the reasons behind non-compliance and patients’ perspectives on how to improve it.

Conclusion

This survey of 529 bariatric surgery patients reports on adherence with post-bariatric surgery nutritional recommendation and attempts to identify the reasons behind poor adherence. We further attempt to understand if it is possible to improve it. Patients reported a number of reasons for why they find it difficult to adhere to the recommended supplements.