Diabetes is a progressive disease process that influences fuel metabolism by the body. 1-3 The prevalence of diabetes has increased eightfold since 1958, but the sharpest acceleration has occurred since 2000. 4 As of 2012, 8.3% of the U.S. population, or 25.8 million Americans, had been diagnosed with diabetes. An estimated 7 million people have diabetes but are undiagnosed.4 Experts predict that by 2025, 15% to 20% of all Americans will have a diagnosis of diabetes or impaired glucose tolerance.5
Type 2 diabetes mellitus (T2DM) is a metabolic disorder resulting from the body's inability to produce insulin. T2DM accounts for up to 95% of all diabetes cases and is most common in adults older than 40. At least 10 million Americans at high risk for T2DM can reduce their risk with diet and exercise.6 T2DM is strongly associated with obesity.6 A person with T2DM can improve insulin sensitivity and glycemic control with exercise, thereby decreasing the need for oral medication and insulin.7
Complications can occur in T2DM when glucose builds up in the blood stream.4 Patients with T2DM are at greater risk for long-term complications such as retinopathy, nephropathy, neuropathy, peripheral vascular disease, lower extremity ulcers and amputations. Diabetes is a major cause of heart disease and stroke and is the seventh leading cause of death in the United States. The American Diabetes Association estimates that more than 224,000 deaths in 2002 were related to diabetes complications. In addition, patients with T2DM are 2 to 4 times more likely to die of heart disease or stroke than healthy patients of the same age.4
The total cost of diabetes in the United States is around $174 billion per year, with $116 billion attributed to direct medical costs and the remaining $58 billion to indirect expenses such as lost work days and permanent disability.6 Due to nonadherence, T2DM can be a challenging disease to manage without understanding the importance of lifestyle modifications such as diet and exercise.
Why Nonadherence Occurs
To improve patient adherence, it is important to understand why nonadherence occurs. According to Delamater,8 most healthcare providers use the term "compliance" instead of "adherence." Compliance is the extent to which a person's behavior coincides with medical advice. Therefore, noncompliance refers to when patients disobey medical advice. Adherence is the "active, voluntary and collaborative involvement of the patient in a mutually acceptable course of behavior to produce a therapeutic result."8 Therefore, adherence means that patients agree on the goal setting, implementation and treatment plan but fail to adhere to it.
A significant amount of literature has documented factors that contribute to nonadherence and self-care behavior; evaluating and understanding perceived barriers can enhance adherence.
Nonadherence to lifestyle modification recommendations occurs when the patient fails to mutually agree to behavior and lifestyle changes known to improve T2DM.9 Studies show that adherence to T2DM recommendations is about 50% for medications and much lower for lifestyle modifications such as diet and exercise.10
Nonadherence to physical activity is defined as engaging in less than 75% of recommended physical activity. Among patients with T2DM, the rate of nonadherence to lifestyle modifications ranges from 40% to 50%.9 In a recent study, rates of nonadherence to diet and exercise were estimated as 63.5% and 64.4%.11 Several studies have shown that lifestyle modification recommendations for healthy diet and exercise are the cornerstones of T2DM prevention and management to improve and manage glycemic control.12 Adherence to diet and exercise can reduce the burden of diabetes and reduce mortality and morbidity associated with T2DM. According to Lin,13 nonadherence to diet and exercise is prevalent, thus increasing poor clinical outcomes, hospitalizations, health care needs, and health care costs.
This study sought to increase healthcare providers' commitment to recommending diet and exercise in the management of T2DM. NPs and PAs play a pivotal role in disease management and patient education. Barriers that prevent patients from adhering to diet and exercise can lead to serious medical complications, including death.11 Removing or reducing these barriers will assist healthcare providers and patients to overcome these obstacles and substantially reduce further medical complications.
The Health Belief Model (HBM) is based on Lewin's theory of goal setting, in which people make decisions about alternative health behaviors. According to this theory, an alternative health behavior can result in a particular outcome.13-16
The HBM is an appropriate model for analyzing health-protecting behaviors. Healthcare providers have a responsibility to educate to their patients and the public about health-protecting behaviors related to T2DM.
To explore the prevalence of nonadherence to diet and exercise recommendations and barriers to adherence, we designed a nonexperimental descriptive correlational survey and sought participants who would self-administer it. The setting was a for-profit clinic that serves urban patients with internal, primary care and pediatric needs. It is located in Memphis.
A convenience sample was used to select 50 participants with a diagnosis of T2DM who received medical care at the clinic during a 3-month period. Participants met eligibility criteria if they were age 18 and older, had a documented diagnosis of T2DM for 2 or more years, and were able to read and write. An ICD 9 code of 250.0 was used to identify the subjects. Participation in the study was voluntary and no incentives or compensation for participation were provided.
Fifty patients agreed to participate. As a result of the 3-month time frame, the 80% power analysis was sufficient for this study.
We used an individualized diabetes questionnaire developed by Stanford Patient Education Research Center at Stanford University School of Medicine (http://patienteducation.stanford.edu/research/diabquest.pdf). We obtained permission to use or adapt the tool. The questionnaire assesses health behaviors, health status, healthcare utilization and self-efficacy, along with demographic and chronic health condition information. For the purpose of this study, the questions and scales in the questionnaire were used to target diet and exercise variables to help assess the understanding and the perceived barriers to nonadherence with diet and exercise recommendations.
We used descriptive statistics including means, frequencies, percentages, t-tests and one-way analysis of variance to answer the research question and to characterize the sample. We used SPSS 21.0 for Windows to analyze the data.
The sample breakdown was as follows: 29 women (58%) and 21 men (42%). Forty-eight percent were white, 44% were black, 4% were Hispanic and 4% were Asian. Marital breakdown was as follows: 46% were single, 40% were married, 8% were separated, 6% were widowed, and no one was divorced.
For chronic conditions, one subject answered "diabetes type 2 and diabetes type 1" and was excluded. Among the remaining 49 subjects, 51% reported having "diabetes type 2, high cholesterol and high blood pressure," 27% reported "diabetes type 2," 14% reported "diabetes type 2 and high blood pressure," and 8% reported "diabetes type 2 and high cholesterol."
Regarding the perception of general health, 36% of subjects perceived their general health as "good," 28% perceived their general health as "fair," 20% perceived their general health as "very good," 10% perceived their general health as "poor," and only 6% perceived their general health as "excellent."
The results of diabetes medication questioning found that 64% of the patients took oral medications for diabetes and 48% had received insulin injections in the prior week. Using the results of medical care documented at the practice, in the prior 6 months, 36% of the participants had sought healthcare three times, 28% had sought it twice, 26% of the participants had visited the office once, and 10% had visited four times. Other data found that 60% of the participants reported no visit to a hospital emergency department, 24% had visited an ED once, and 16% had gone twice. Also in the prior 6 months, 66% had not been hospitalized one night or longer, 24% had been hospitalized one night or longer once, and 10% had been hospitalized one night or longer twice.
The descriptive statistical data gathered in this study contribute to understanding of reasons for perceived barriers that lead to nonadherence. This study reiterates the need for providers to develop and implement lifestyle modification initiatives among all patients with T2DM.
Exercise can lead to significant improvements in physical abilities, as well as decreased perceptions of pain, fatigue, depression and insomnia.16
Based on symptoms of fatigue, pain and shortness of breath, there was a statistically significant difference (p = 0.029) in independent comparisons among the four ethnic groups. In addition, there was a statistically significant difference in independent comparisons among the four marital status groups in physical activity of (p = 0.032) and daily activities (p = 0.015). These findings suggest that the results can be obtained with a new sample size, hence with a higher confidence interval of 95%.
Although there was no statistically significant difference in independent comparisons among the four ethnic groups, in terms of physical activity (p = 0.237) and daily activities (p = 0.211), the findings are relevant to clinical practice. According to Testa et al,17 improvements in glycemic control affect quality of life by leading to fewer physical symptoms, including pain and fatigue.17
For patients with T2DM, healthy eating requires consistent amounts and timing of meals to maintain glycemic control. Glycemic control is achieved by monitoring carbohydrate, protein and fat intake to meet metabolic needs and food preferences.18 In this study, patients indicated the number of times in the prior week they had eaten breakfast. The reported maximum score was 7 times in the prior week with a mean score of 3, meaning that most patients were eating breakfast 3 times per week.
The majority of adults with T2DM use insulin and/or oral diabetes medications, in addition to diet and exercise, to achieve adequate blood glucose control. Maintaining adherence to oral diabetes medications has been one of the key strategies in achieving long-term glycemic control.19 In this study population, 64% of patients took oral diabetes medication and 48% took insulin. Research has shown that patients are more adherent to oral therapy than insulin.
The study found no statistical difference between men and women in symptoms of fatigue, pain and shortness of breath (p = 0.454), physical activity (p = 0.251), confidence (p = 0.966) and medical care (p = 0.740). Although this study may not have been as robust as previous research, it has clinical merit and significance in T2DM care. We identified no single reason for nonadherence to diet and exercise. Rather, the research identified a need for continuous educational measures and strategies to improve glycemic control through diet and exercise modification.
The most significant limitation of the study was the sample size of 50 patients. The study was conducted in an urban internal medicine and pediatric clinic, therefore its findings may not be generalizable to other populations and other geographic locations.
Lifestyle modification that includes diet and exercise is the cornerstone of diabetes education. With a unique ability to provide patient care using a team and multidisciplinary approach, NPs and PAs are in a unique position to stand as leaders at the forefront of diabetes care. Future research should be obtained from a larger sample of T2DM patients in other settings to determine whether the results of this study are representative of the larger population.
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Terrell Carpenter is a family nurse practitioner at Memphis Internal Medicine and Pediatrics in Memphis. Laurie Bagwell is a family nurse practitioner who is an assistant professor of nursing at Union University in Germantown, TN. The authors have completed a disclosure statement and report no relationships related to this article.