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Comment on: Cognitive function predicts 24 month weight loss success following bariatric surgery
Cognition and 24-Month Postoperative Weight Loss / Surgery for Obesity and Related Diseases 9 (2013) 765–772
771
Editorial comment
Comment on: Cognitive function predicts 24 month weight loss success following bariatric surgery Received April 30, 2013; accepted April 30, 2013
The accompanying article provides strong support for the relation between cognitive function early after bariatric surgery and weight loss success 2 years later (percent weight loss and body mass index). The investigators offer adherence to the postoperative guidelines as a possible mediator of the link between cognitive function and postoperative weight loss success after bariatric surgery. Although this is a commonly proposed mechanism for the variability in weight loss outcomes after surgery, there are only a few studies to date that have directly addressed this hypothesis. The surgical literature has shown that by 2 years after bariatric surgery, variability in weight loss success begins to emerge. There is great concern regarding this pattern and uncertainty about why this occurs. Evidence from the current paper shows that psychological factors (e.g., attention, executive function, memory) are one notable predictor of this variability in outcome. It makes intuitive sense then that each individual’s behavior and compliance to the prescribed regimen would begin to have an impact on weight loss by this time point. So how do we conclusively demonstrate this? A critical point to consider when discussing postoperative patient adherence is the complexity and extensiveness of the bariatric surgery guidelines and recommendations held as the current standard of care. As an example, the document published by the American Association of Clinical Endocrinologists, The Obesity Society, and The American Society for Metabolic and Bariatric Surgery in 2008, which describes the guidelines, is 83 pages in length [1]. In clinical practice, this vast set of recommendations is translated and disseminated to patients in a variety of contexts. A coordinated and redundant educational process is often necessary to communicate this information to patients. The information can be delivered via preoperative clinic visits, handouts/websites/ DVDs, nutritional visits, psychological consultations, surgical appointments, surgical informed consent meetings, hospital discharge instructions, postoperative clinic visits, support group meetings, and published books on bariatric surgery. Given the intricacy of the guidelines, it would seem that individuals with a higher level of cognitive function would have an advantage in successfully implementing these recommendations. So how do we incorporate adherence variables into our research in such a way that this proposed mediation is better understood? For guidance, we can consider how researchers in other clinical settings have investigated cognitive function, adherence, and medical outcome. In a study of older (≥60 years
of age) type 2 diabetic patients, greater cognitive impairment was associated with worse diabetes control (as indexed by HbA1c level) and self-care, even after adjusting for age, education, medical co-morbidity, and depression [2]. During the 1-year follow-up, diabetes management continued to decline even when a caregiver was available. In a sample of hypertensive patients (≥60 years of age), lower scores on a mental status examination were associated with lower adherence rates with therapeutic guidelines and lower blood pressure control [3]. Lower levels of cognitive function predicted poorer medication adherence among older HIVpositive adults [4]. In addition, cognitive impairment (verbal learning, immediate memory, and delayed memory) was significantly associated with poorer medication adherence among a group of outpatient veterans with heart failure [5]. The authors advocate for routine screening of cognitive impairment in patients with heart failure to provide an opportunity to intervene on medication adherence rates. There have been few studies of adherence among bariatric surgery patients. One study examined preoperative adherence to behavioral treatment recommendations made by the psychologist subsequent to the presurgical psychological screening [6]. Nonadherence was predicted by male gender, higher hostility scores, and degree of difficulty in implementing the recommendations. Interestingly, in one of the few studies looking at adherence variables among bariatric surgery patients, the degree of difficulty of the recommendation was a significant predictor of adherence for the recommendation. A recent study of attendance at post–bariatric surgery medical visits (1 marker of adherence) found that those with a higher rate of attendance were more likely to be older, Caucasian, and have lower phobic anxiety scores than those with a lower rate of attendance [7]. Individuals more likely to attend their post–bariatric surgery behavioral health visits had shorter distances to travel to the clinic, lower levels of hostility, less anxiety, and less phobic anxiety than those patients less likely to attend these sessions. To better understand how adherence might be mediating the link between cognitive function and weight loss outcomes after bariatric surgery, researchers need better quality postoperative adherence data to examine. These variables could include percent postoperative clinic visits attended, frequency/amount/type of physical activity, daily protein intake, frequency of adherence to the vitamin regimen, prescription medication adherence, rate of adherence to proton pump inhibitors, meal structure data (number of meals per day, number of snacks), the presence of grazing behavior, the presence of night eating behavior, frequency of
772
M. B. Spitznagel et al. / Surgery for Obesity and Related Diseases 9 (2013) 765–772
spontaneous vomiting from overeating, frequency of binge eating, frequency of sweets eating, consumption of sugary beverages, consumption of alcohol, and smoking status. Because we are already collecting much of these data during the course of clinical care, a systematized method of coordinating and reporting the information is needed. This documentation along with the extensive surgical, medical, nutritional, and psychological data already being collected would provide us with an opportunity to better understand how these patient variables interact to affect long-term success with weight loss and weight loss maintenance. Once this has been clarified, clinicians working with bariatric surgery patients would have a much better sense of empirically validated characteristics that place patients at risk for poorer weight loss outcome and behaviors that could be targeted for intervention. Katherine L. Applegate, Ph.D. Duke University Medical Center Durham, North Carolina
References [1] Mechanick JI, Kushner RF, Sugarman HJ, et al. AACE/TOS/ASMBS medical guidelines for clinical practice for the perioperative nutritional, metabolic, and nonsurgical support of the bariatric surgery patient. Endoc Pract 2008;14:1–83. [2] Feil DG, Pearman A, Victor T, et al. The role of cognitive impairment and caregiver support in diabetes management of older outpatients. Int J Psychiatry Med 2009;39:199–214. [3] Vinvoles E, de la Figuera M, Gonzalez-Segura D. Cognitive function and blood pressure control in hypertensives over 60 years of age: COGNIPRES study. Curr Med Res Opin 2008;24:3331–9. [4] Barclay TR, Hinkin CH, Castellon SA, et al. Age-associated predictors of medication adherence and HIV-positive adults: health behaviors, self-efficacy, and neurocognitive status. Health Psychol 2007;26:40–9. [5] Hawkins LA, Kilian S, Firek A, Kashner TM, Firek CJ, Silvet H. Cognitive impairment and medication adherence in out-patients with heart failure. Heart Lung 2012;41:572–82. [6] Friedman KE, Applegate KL, Grant JP. Who is adherent with preoperative psychological treatment recommendations among weight loss surgery candidates? Surg Obes Relat Dis 2007;3:376–82. [7] McVay MA, Friedman KE, Applegate KL, Portenier DD. Patient predictors of follow-up care attendance in Roux-en-Y gastric bypass patients. Surg Obes Relat Dis. Epub 2012 Dec 5.
771
Editorial comment
Comment on: Cognitive function predicts 24 month weight loss success following bariatric surgery Received April 30, 2013; accepted April 30, 2013
The accompanying article provides strong support for the relation between cognitive function early after bariatric surgery and weight loss success 2 years later (percent weight loss and body mass index). The investigators offer adherence to the postoperative guidelines as a possible mediator of the link between cognitive function and postoperative weight loss success after bariatric surgery. Although this is a commonly proposed mechanism for the variability in weight loss outcomes after surgery, there are only a few studies to date that have directly addressed this hypothesis. The surgical literature has shown that by 2 years after bariatric surgery, variability in weight loss success begins to emerge. There is great concern regarding this pattern and uncertainty about why this occurs. Evidence from the current paper shows that psychological factors (e.g., attention, executive function, memory) are one notable predictor of this variability in outcome. It makes intuitive sense then that each individual’s behavior and compliance to the prescribed regimen would begin to have an impact on weight loss by this time point. So how do we conclusively demonstrate this? A critical point to consider when discussing postoperative patient adherence is the complexity and extensiveness of the bariatric surgery guidelines and recommendations held as the current standard of care. As an example, the document published by the American Association of Clinical Endocrinologists, The Obesity Society, and The American Society for Metabolic and Bariatric Surgery in 2008, which describes the guidelines, is 83 pages in length [1]. In clinical practice, this vast set of recommendations is translated and disseminated to patients in a variety of contexts. A coordinated and redundant educational process is often necessary to communicate this information to patients. The information can be delivered via preoperative clinic visits, handouts/websites/ DVDs, nutritional visits, psychological consultations, surgical appointments, surgical informed consent meetings, hospital discharge instructions, postoperative clinic visits, support group meetings, and published books on bariatric surgery. Given the intricacy of the guidelines, it would seem that individuals with a higher level of cognitive function would have an advantage in successfully implementing these recommendations. So how do we incorporate adherence variables into our research in such a way that this proposed mediation is better understood? For guidance, we can consider how researchers in other clinical settings have investigated cognitive function, adherence, and medical outcome. In a study of older (≥60 years
of age) type 2 diabetic patients, greater cognitive impairment was associated with worse diabetes control (as indexed by HbA1c level) and self-care, even after adjusting for age, education, medical co-morbidity, and depression [2]. During the 1-year follow-up, diabetes management continued to decline even when a caregiver was available. In a sample of hypertensive patients (≥60 years of age), lower scores on a mental status examination were associated with lower adherence rates with therapeutic guidelines and lower blood pressure control [3]. Lower levels of cognitive function predicted poorer medication adherence among older HIVpositive adults [4]. In addition, cognitive impairment (verbal learning, immediate memory, and delayed memory) was significantly associated with poorer medication adherence among a group of outpatient veterans with heart failure [5]. The authors advocate for routine screening of cognitive impairment in patients with heart failure to provide an opportunity to intervene on medication adherence rates. There have been few studies of adherence among bariatric surgery patients. One study examined preoperative adherence to behavioral treatment recommendations made by the psychologist subsequent to the presurgical psychological screening [6]. Nonadherence was predicted by male gender, higher hostility scores, and degree of difficulty in implementing the recommendations. Interestingly, in one of the few studies looking at adherence variables among bariatric surgery patients, the degree of difficulty of the recommendation was a significant predictor of adherence for the recommendation. A recent study of attendance at post–bariatric surgery medical visits (1 marker of adherence) found that those with a higher rate of attendance were more likely to be older, Caucasian, and have lower phobic anxiety scores than those with a lower rate of attendance [7]. Individuals more likely to attend their post–bariatric surgery behavioral health visits had shorter distances to travel to the clinic, lower levels of hostility, less anxiety, and less phobic anxiety than those patients less likely to attend these sessions. To better understand how adherence might be mediating the link between cognitive function and weight loss outcomes after bariatric surgery, researchers need better quality postoperative adherence data to examine. These variables could include percent postoperative clinic visits attended, frequency/amount/type of physical activity, daily protein intake, frequency of adherence to the vitamin regimen, prescription medication adherence, rate of adherence to proton pump inhibitors, meal structure data (number of meals per day, number of snacks), the presence of grazing behavior, the presence of night eating behavior, frequency of
772
M. B. Spitznagel et al. / Surgery for Obesity and Related Diseases 9 (2013) 765–772
spontaneous vomiting from overeating, frequency of binge eating, frequency of sweets eating, consumption of sugary beverages, consumption of alcohol, and smoking status. Because we are already collecting much of these data during the course of clinical care, a systematized method of coordinating and reporting the information is needed. This documentation along with the extensive surgical, medical, nutritional, and psychological data already being collected would provide us with an opportunity to better understand how these patient variables interact to affect long-term success with weight loss and weight loss maintenance. Once this has been clarified, clinicians working with bariatric surgery patients would have a much better sense of empirically validated characteristics that place patients at risk for poorer weight loss outcome and behaviors that could be targeted for intervention. Katherine L. Applegate, Ph.D. Duke University Medical Center Durham, North Carolina
References [1] Mechanick JI, Kushner RF, Sugarman HJ, et al. AACE/TOS/ASMBS medical guidelines for clinical practice for the perioperative nutritional, metabolic, and nonsurgical support of the bariatric surgery patient. Endoc Pract 2008;14:1–83. [2] Feil DG, Pearman A, Victor T, et al. The role of cognitive impairment and caregiver support in diabetes management of older outpatients. Int J Psychiatry Med 2009;39:199–214. [3] Vinvoles E, de la Figuera M, Gonzalez-Segura D. Cognitive function and blood pressure control in hypertensives over 60 years of age: COGNIPRES study. Curr Med Res Opin 2008;24:3331–9. [4] Barclay TR, Hinkin CH, Castellon SA, et al. Age-associated predictors of medication adherence and HIV-positive adults: health behaviors, self-efficacy, and neurocognitive status. Health Psychol 2007;26:40–9. [5] Hawkins LA, Kilian S, Firek A, Kashner TM, Firek CJ, Silvet H. Cognitive impairment and medication adherence in out-patients with heart failure. Heart Lung 2012;41:572–82. [6] Friedman KE, Applegate KL, Grant JP. Who is adherent with preoperative psychological treatment recommendations among weight loss surgery candidates? Surg Obes Relat Dis 2007;3:376–82. [7] McVay MA, Friedman KE, Applegate KL, Portenier DD. Patient predictors of follow-up care attendance in Roux-en-Y gastric bypass patients. Surg Obes Relat Dis. Epub 2012 Dec 5.