Relationships between patient knowledge and the severity of side effects , daily nutrient intake , psychological status , and performance status in lung cancer patients

Aim We aimed to assess the relationships of patient education with the severity of treatment-induced side effects, daily calorie and protein intake, psychological status, and performance status in patients with lung cancer. Methods The study patients were divided into an intervention (n = 62) and a control group (n = 110). The patients in the intervention group were provided with information about treatment, diet, and rehabilitation during chemotherapy. The patients in the control group were not specially provided with that information. Results We observed significant differences between the intervention and control groups with respect to low daily protein intake (54.84% vs. 70.00%, p = 0.046), prevalence of depression (51.61% vs. 70.91%, p = 0.011), prevalence of severe side effects of treatment (14.52% vs. 37.27%, p = 0.002), and good performance status (75.81% vs. 55.45%, p = 0.008). Conclusions Our results suggest that educating patients about cancer treatment and rehabilitation can lead to increased protein intake, a lower prevalence of depression, lesser side effects from cancer treatments, and improved performance status.


INTRODUCTION
The incidence of lung cancer, a common disease in China, has increased in recent years 1 .Chemotherapy is an important part of treatment for lung cancer patients.However, while on treatment, patients often experience great physical and mental distress 2,3 and poor performance status and quality of life (qol) 3 as a result of severe treatment-induced side effects.
Psychosocial intervention is a valuable adjunct to physical treatment for cancer patients 4 .Studies suggest that psychosocial interventions for patients can effectively reduce their distress, enhance treatment adherence, and improve outcomes [5][6][7] .
Patient education is one type of psychosocial intervention.Educating patients about their disease, its treatment, potential side effects, and qol can reduce anxiety 8 , enhance coping mechanisms 9 , reduce decisional conflicts, promote patient autonomy, and improve the patient experience 10 .Patients who understand their disease and its treatment also comply better with therapy 11 , which translates into better outcomes.
The effects of education on cancer patients have been reported in many studies [11][12][13][14] .A meta-analysis of thirtyseven controlled studies of psychosocial interventions in adult cancer patients reported that the overall effect size of psychosocial interventions on the qol of patients is 0.31 12 .An analysis of Internet and computer-based education programs for prostate cancer patients reported a significant increase in disease knowledge and satisfaction with treatment options 11 .Another study adopted an experimental time series design by comparing two groups of 25 cancer patients matched by treatment type and sex.The authors showed that, compared with a control group, the experimental group exhibited significantly less anxiety during radiation therapy-an effect that was maintained throughout a treatment period of up to 7 weeks 13 .In a randomized controlled trial 14 in which patients were randomly assigned to individualized education (n = 34) or to a control group that did not receive education (n = 33), researchers reported a significantly improved average pain severity in the experimental group than in the control group (p = 0.014).
Side effects, depression or anxiety, nutrition status, and performance status are foci of attention in clinical cancer care.Poor nutrient intake and poor performance status are important factors affecting qol in patients [15][16][17][18][19][20][21] .Performance status has long been recognized as a predictor of oncologic outcome 15 , and many studies have shown its importance as a predictor of survival in advanced cancer [16][17][18] .A poor nutrition status is associated with fatigue 19 and poor qol 20 , and is correlated with an increased risk of severe hematologic toxicity after chemotherapy 21 .
Few studies have assessed the effects of patient education on nutrition status and performance status in cancer patients.We therefore set out to assess the relationships of patient education with side effects, daily calorie and protein intake, depression, anxiety, and performance status in a group of lung cancer patients.

Participants
The study participants consisted of patients admitted to two provincial-level hospitals in Fuzhou, China, between December 2008 and January 2010.Eligibility criteria included age of 18 years or older; awareness of the lung cancer diagnosis; lack of a history of mental or psychological disease; capability to hear normal conversation; and receipt of chemotherapy.
Patients hospitalized between December 2008 and June 2009 constituted the intervention group; those hospitalized between July 2009 and January 2010 constituted the control group.A total of 172 patients were approached to enrol (62 eligible between December 2008 and June 2009, and 110 eligible between July 2009 and January 2010), and none declined to participate.
All eligible participants were newly diagnosed with lung cancer, and none had previously received chemotherapy.Medical records confirmed that the patients had no prior experience with cancer or chemotherapy treatments.All patients received intravenous infusion chemotherapy, which included cyclophosphamide, carboplatin, vincristine, and cisplatin.All participants provided written informed consent, and the study was approved by relevant institutional review boards for human research of Fujian Medical University.

Intervention
Each participant in the intervention group was assigned to a trained medical graduate student who provided information on the nutritional management of side effects and on exercise and relaxation techniques, and who answered questions about treatment and diet during the first treatment cycle.The graduate students performed this work weekly, every Monday, for 4 consecutive weeks.
Participants in the control group were not specially provided with knowledge about their cancer treatment and rehabilitation.
During the 5th week of treatment, the patients in the intervention and control groups were contacted by trained nurses in the hospitals.The patients were asked to complete questionnaires about their diet, psychological status, and treatment side effects.At the end of the first treatment cycle, the performance status of the patients was assessed.

Measures
The food frequency survey method 22 was used to obtain information about diet for each patient during the preceding week.Daily intakes of energy and protein were then calculated for every patient using the Food Composition Database 23 .Based on reference values proposed by the Chinese Nutrition Society 23 , the nutrient intakes by the patients were evaluated.A daily energy intake below 2400 kcal (men) or 2100 kcal (women) and a daily protein intake below 70 g (men) or 65 g (women) are defined as "low." The Hospital Anxiety and Depression Scale is a 14-item questionnaire (7 items on the Anxiety subscale and 7 on the Depression subscale) that is used to evaluate anxiety and depression in patients 24 .Scores for each item range from 0 to 3. Patients score the items based on their current situation.Scores on the Anxiety and Depression subscales therefore range from 0 to 21.A score higher than 11 on the relevant subscale is considered to indicate severe depression or anxiety 25 .The Chinese version of the Hospital Anxiety and Depression Scale has been confirmed to be suitable for Chinese patients 26 .
Information about side effects was obtained from a self-administered questionnaire given to the participants.Treatment-induced side effects were examined for seven bodily systems: gastrointestinal, respiratory, liver and kidney, heart, hair, skin, and nervous system.An ordinal scale was used to determine the severity of the side effects for each system: "not at all," "mild," "moderate," "somewhat severe," and "severe" (scored as 1, 2, 3, 4, and 5 respectively).The total score is the sum of the scores for the seven systems, with a high total score indicating severe side effects."Mild side effects" was defined as a total score of less than 8, and "severe side effects" was defined as a total score higher than 9.
Eastern Cooperative Oncology Group performance status 25 was measured for all patients.This measure denotes the functional status of the patient on a scale of 0 to 4. An Eastern Cooperative Oncology Group score in the 2-4 range indicates a poor performance status; 0-1 indicates a good performance status.

Statistical Analysis
Percentages are used to describe the distributions of age, sex, education level, disease stage, and histology in the intervention and control groups.The chi-square test was used to compare differences between the intervention and control groups in the prevalence rates of severe side effects, anxiety, depression, low calorie intake, low protein intake, and poor performance status.The significance level was set at 0.05, and all p values are two-tailed.

RESULTS
The mean ages of the participants in the intervention (n = 62) and control (n = 110) groups were 53.39 ± 9.74 years and 55.51 ± 11.40 years respectively.Table i shows the demographic and disease characteristics of the patients in the two groups.
In the intervention group, the median daily energy (kilocalories) and protein (grams) intakes were 2150 kcal and 69.6 g for men and 2010 kcal and 66.1 g for women.The median intakes in the control group were 1853 kcal and 56.6 g for men and 1749 kcal and 54.2 g for women.Thus, compared with patients in the control group, patients in the intervention group had higher median daily energy and protein intakes, even though their intakes were still mostly lower than those proposed by the Chinese Nutrition Society 23 .
Table ii shows the relationships of patient education with energy intake, protein intake, anxiety, depression, side effects, and performance status.Compared with patients in the control group, patients in the intervention group showed significantly better daily protein intake (p = 0.046), a reduced prevalence of depression (p = 0.011), reduced severity of side effects (p = 0.002), and better performance status (p = 0.008).

DISCUSSION AND CONCLUSIONS
Our findings suggest that patient education has associations with side effects, daily protein intake, depression, and performance status.Providing treatment-and rehabilitation-related knowledge can result in increased protein intake, a lower risk of depression, reduced severity of side effects, and an improved performance status.
Most patients with cancer experience psychological distress 27 .Researchers have found that patients with psychological distress are less able to perform self-care 28 .Patient education is an important psychological intervention.Teaching patients how to reduce their own psychological distress can help them to manage side effects with self-care behaviours 29 .Studies have found that education about treatment, side effects, and self-care behaviors can minimize the side effects of chemotherapy, reduce symptom distress, and improve qol [30][31][32] .Our findings accord with those earlier studies.
In China, many patients with lung cancer have little knowledge about cancer treatment and rehabilitation 33,34 ; they believe that a person with cancer will eventually die 34 .This lack of treatment-and rehabilitation-related knowledge results in the patient losing confidence in treatment and rehabilitation and experiencing increased spiritual distress and psychological problems 35 .The patients lack knowledge about managing side effects, and they attach little importance to nutrient intake.If doctors and nurses in the hospital can provide cancer patients with treatmentand rehabilitation-related information during therapy, the patients might take a positive and active attitude toward treatment and rehabilitation, which is helpful for the effective management of the side effects of treatment 10,36 .
Patient education can take several approaches: face-to-face conversation, written or printed materials,  computer-assisted learning, telephone calls, audio tapes, and video presentations 37 .For hospitalized patients, faceto-face conversations and written materials are suitable for patient education.Given that the education levels of a large proportion of the cancer patients in Fujian are low, written material might be too advanced for patients to read and comprehend.Providing knowledge related to cancer treatment and rehabilitation in face-to-face conversations is suitable for patients with less education.In addition, face-to-face conversations can be adjusted to meet the individual needs of patients.Thus, the present study used face-to-face conversations to educate patients.Our education method is effective and easy to perform in all hospitals.
Our study has several limitations.The patients were grouped based on the time of their admission to hospital; thus, our study is not a randomized controlled trial.The economic conditions of the families and the social resources (support from family or friends) of the patients might therefore differ between the intervention and control groups.We did not control for or assess the type or amount of additional information that patients in both groups might have received from family, friends, and the media (newspapers, television, Internet).Those limitations could potentially mask the true effect of patient education.However, the demographic and disease characteristics of the patients in both groups were similar, and so the results might not contain large estimation errors.Another limitation of our study was its lack of a pre-intervention assessment of the outcome variables; changes might therefore not be able to be entirely attributed to the intervention.Future studies should be conducted with these modifications: a parallel control group; ascertainment of how much information the patients in both groups receive from other sources; and a baseline assessment of diet, psychological status, and performance status in both groups.

CONFLICT OF INTEREST DISCLOSURES
We have read and understood Current Oncology's policy on disclosing conflicts of interest, and we declare that we have none.This study has no financial relationship with any organization that sponsored the research and authorship.The corresponding author has full control of all primary data and will allow the journal to review the data if requested.

AUTHOR AFFILIATIONS
*Department of Epidemiology and Health Statistics, Fujian Medical University, Fuzhou, PRC; † Department of Nursing, Fujian Health College, Fuzhou, PRC; ‡ Fujian Tumor Hospital, Fuzhou, PRC.

TABLE I
Characteristics of patients with lung cancer in the intervention and control groups