The Eleonoren Clinic is a rehabilitation center of the German Pension Insurance Organization (Hessen) (Deutsche Rentenversicherung Hessen) for gastroenterology and metabolic disorders as well as tumour diseases. The clinic is also a qualified training and treatment center for type 1 and type 2 diabetes (German Diabetes Association Step 1) and a qualified teaching hospital for nutrition medicine (German Academy for Nutritional Medicine).

For the treatment of obesity, the Eleonoren Clinic uses a multi-modular and multi-stage therapeutic process. At the beginning of the two-year treatment program, patients attend a four-week inpatient core program in a closed group of eight to ten participants. The concept includes nutrition, behaviour, and exercise therapy modules. During the first year after the inpatient stay, the aim is further weight reduction. During this time, the Eleonoren Clinic maintains constant contact with the patients by mail and by phone. Patients who were successfully assisted in reducing their body weight by ≥10% could participate in a two-week stabilization therapy. During the stabilization program relapse prevention module, lifestyle changes are checked and motivation is stabilized. During the second year of the program, patients are expected to maintain the attained weight. The program ends with a one-week aftercare module.

To evaluate the changes during the four-week inpatient care program, the following parameters were examined: weight-associated parameters (body weight, BMI, EWL), circulation-associated parameters (blood pressure, heart rate), glucose-metabolism parameters (blood glucose day profile, HbA1c), body composition (BIA), and life quality (SF-36 questionnaire). A total of 64 patients took part in the study from February 25, 2014 to January 7, 2015. Patients were selected irrespective of age, origin, and profession. They were expected to fulfill the following inclusion criteria: Grade 1 obesity or more (BMI >30 kg/m²), minimum age of 18 years, no physical limitations of the musculoskeletal system, no inappropriate exhaustion during ordinary physical stress, and no diseases with cardiac or pulmonary limitations. Patients with severe acute cardiopulmonary pre-existing diseases (heart attack, pulmonary embolism), severe accompanying diseases (tumour diseases), clinical indications and echocardiographic signs of decompensated heart failure, fatigue, rhythm disturbances, dyspnea or angina pectoris during ordinary physical stress, severe orthopedic disease, addiction (except nicotine abuse), patients undergone bariatric surgery, pregnancy, and secondary obesity were excluded from the study.

The timescale of the examinations during the inpatient stay is summarized in [Table/Fig-1]. The project was examined and approved by the Ethics Committee of the University of Munich.

The aim of the nutrition therapy was to establish a negative energy balance. This was achieved by a hypocaloric mixed diet with a reduced fat content. The desired energy deficit was based on patient basal metabolism and should amounts to 500–800 kcal per day. No hypocaloric diet <1200 kcal per day was realized. The energy consumption was enhanced by exercise therapy to achieve a negative energy balance. During the weight reduction phase, the muscle mass was initially to be maintained as far as possible and should be continued to be increased later. Patient’s physical fitness was improved to increase the cardiopulmonary capacity. By improving the nutrition therapy, behavioural therapy and the movement therapy an enhancement of life quality and a stabilization of the introduced lifestyle changes were expected to be achieved. Trained psychologists were entrusted with the behaviour therapy. By changing their own lifestyles, patients were sensitized to their nutrition and exercise habits and were enabled to change these habits independently as required. A primary focus of the obesity program was behavioural therapy offered as an interactive group session. During this therapy, the motivation for weight reduction with short and long term goals and the vicious circle of ineffective dietary efforts were addressed. In addition, the process of an effective dietary regime was elucidated.

The physical examination on the first day of rehabilitation included a cardiac inspection and auscultation as well as an auscultation and percussion of the lung. The body size (without shoes) was determined by means of a measuring stick and the body weight in patient’s undergarments, by means of a calibrated scale. The collected data were used to calculate the BMI. Blood pressure was measured after five minutes of relaxation on the upper arm using a sphygmomanometer (Riva-Rocci method). Based on the size of the upper arm, different cuff sizes were chosen. The subjectively experienced life quality and physical fitness were recorded using the SF-36 questionnaire [12]. In addition to the full scale, the subscales physical functioning, role physical, role emotional, vitality, mental health, social functioning, bodily pain and general health were analysed separately. The BIA (Multi Frequency Analyser BIA 2000-M; Data Input GmbH, Software Nutri 4) and the resting electrocardiogram (custo card m; custo med GmbH) were conducted under fasting conditions on the morning of the second day of rehabilitation.

The second round of examinations were performed between the 26^th and 29^th days of rehabilitation.

The software SPSS/PASW version 18.0 was used for the statistical analysis. For metric variables, the mean and standard deviations were calculated. Potential correlations between metric variables were analysed by means of a Pearson’s correlation analysis. Mean differences were examined using t-tests (unpaired and paired samples). In the case of unpaired samples, variance homogeneity was confirmed by a Levene’s test. The two sided significance level was set at α = 0.05. A p-value <0.05 was defined as significant, whereas, p-value <0.01 as highly significant.

A total of 64 patients participated in the study between February 25, 2014 and January 7, 2015. Twelve patients did not complete the study (n=7) or had to be excluded because of emerging diseases/accidents (n=5). A total of 52 patients with an average age of 46.1±11.0 years (minimum 22 years, maximum 66 years) completed the entire study plan. Forty of these patients (47.1±11.1 years) were males and twelve were females (42.8±10.4 years). The average time interval between the examination at the beginning (U1) and the end (U2) of the inpatient rehabilitation was 26.98 days (from 26 to 28 days).

The body weight at U1 (135.04±26.82 kg) was reduced to 127.95±24.75 kg at U2 [Table/Fig-2]. The body weight loss, the percentage weight reduction, the EWL, and the decrease of BMI between U1 and U2 were highly significant (p<0.01). The patients achieved a mean EWL of 13% and a maximum EWL of 40%. The BMI was reduced by an average of 2.3 kg/m². Patients with obesity grade 1 at U1 achieved a highly signifcant weight reduction of 4.56% (n=9), patients with obesity grade 2 at U1 achieved a highly significant reduction of 5.53% (n=12), and patients with obesity grade 3 at U1 achieved a highly significant weight reduction of 5.17% (n=31).

During the rehabilitation program, blood glucose levels dropped dramatically in the study group [Table/Fig-3]. The differences between U1 and U2 were highly significant for blood glucose measured at 7:00 a.m. and 9:30 a.m. for HbA1c and for fasting glucose levels estimated in the laboratory (p<0.001), and significant for blood glucose measured at 11:00 a.m. (p=0.039).

A total of 24 of the 52 patients (46.2%) had been diagnosed with diabetes mellitus. Seven patients were treated exclusively through diet. Seventeen patients received an oral medication (e.g., metformin), insulin, or both. In this subgroup, changes in estimated glucose values were also (highly) significant (p- value between 0.001–0.043) [Table/Fig-4]. Patients without diabetes did not show a significant reduction of glucose values during rehabilitation, except the glucose level estimated in laboratory testing (p<0.001) [Table/Fig-5].

In the study group, systolic as well as diastolic blood pressure dropped during rehabilitation [Table/Fig-6]. The differences between U1 and U2 were 12.8 mmHg for systolic blood pressure and 6.8 mmHg for diastolic blood pressure. The reductions were highly significant.

A total of 38 of 52 patients (73.1%) had been diagnosed with arterial hypertension. Fourteen patients had normal blood pressure values. Fourteen patients with arterial hypertension were treated with ß-blockers, 19 patients with angiotensin-converting-enzyme (ACE) blockers, 14 patients with calcium-antagonists, 20 patients with diuretics, and 11 patients with angiotensin-1-receptor antagonists. No statistical differences were found in regard to blood pressure values between patients with or without diagnosed arterial hypertension at the beginning and the end of rehabilitation [Table/Fig-7].

The heart rate was analysed under resting conditions at the beginning and at the end of the treatment [Table/Fig-8]. During the treatment, the mean heart rate decreased from 77 to 66 beats per minute. The reduction in the heart rate was highly significant (p<0.001).

The BIA revealed a highly significant reduction in the proportion of body fat between the beginning and the end of the program (U1: 38.48%±7.53%, U2: 36.24%±7.83%, p<0.001, see [Table/Fig-9]). In addition, (highly) significant differences between U1 and U2 were detected for body water (p=0.004), lean body mass (p<0.001), cell content (p=0.011), phase angle (p=0.019), and extracellular water (p=0.002). No statistical differences could be found for extracellular mass (p=0.076), body cell mass (p=0.118), basal metabolic rate (p=0.360), and intracellular water (p=0.625).

SF-36 questionnaire data from 48 patients were evaluated. Four patients did not complete the questionnaire because of insufficient German language skills. The analysis revealed highly significant improvements after rehabilitation for all subscales of the SF-36 questionnaire (physical functioning, role physical, role emotional, vitality, mental health, social functioning, bodily pain, and general health).

During the four week inpatient obesity rehabilitation program at the Eleonoren Clinic, the present study group achieved a mean body weight loss of 7.1 kg (5.1%). The most extreme weight loss was 13.4%, and the average reduction in BMI was 2.3 kg/m².

One goal of the interdisciplinary guidelines of the German Obesity Society for the prevention and therapy of obesity is an initial reduction in body weight by 5%, for people with obesity Grade 1 within a six to twelve months period. This aim was nearly achieved during the four week inpatient rehabilitation program (4.56% body weight loss for patients with obesity Grade 1). For people with obesity Grade 2 and 3, body weight reduction during the same period should be 10%. In the present study, people already lost one-half of the required weight (5.53% patients with obesity grade 2 and 5.17% patients with obesity Grade 3) during the four week inpatient rehabilitation program. The successful weight reduction is likely due to the combination of behavioural/exercise modules and nutritional education during inpatient therapy. The reduction in weight can be interpreted as a result of an initial lifestyle change towards increased physical activity and calorie-reduced nutrition. Several studies have already confirmed the success of a combination of exercise and nutrition therapy for weight reduction [13–15].

Sufficient compliance of patients is an indispensable prerequisite for successful weight reduction [16]. At the Eleonoren Clinic in Winterkasten, an interdisciplinary team of physicians, psychologists, nurses, physiotherapists, diabetes assistants, diet assistants, and nutrition consultants ensure effective therapy progress.

During the four week inpatient rehabilitation program, the diabetic metabolic state improved significantly. No correlation was found between weight-associated parameters (BMI-U1, weight reduction) and glucose metabolism-associated parameters (HbA1c-U1, glucose U1).

Arterial hypertension is an independent risk factor for cardiovascular diseases such as myocardial infarction, stroke, sudden cardiac death, and (terminal) renal failure. The prevalence of arterial hypertension in the present study group (patients with obesity 1-3) was estimated at 73% and therefore comparable to the results of the Hypertension and Diabetes Risk Screening and Awareness (HYDRA) study [17].

Weight reduction reduces systolic and diastolic blood pressure [3]. A meta-analysis of studies on the correlation between weight loss and blood pressure revealed a significant weight reduction of 5.1 kg accompanied by a mean systolic and diastolic blood pressure decrease of 4.44 mmHg and 3.57 mmHg, respectively, during an average observation period of 66.6 months. The decline per kilogram of body weight lost was equal to 1.05 mmHg and 0.92 mmHg for systolic and diastolic blood pressure, respectively [18]. In the course of a six month intervention program with the object of a lifestyle change, patients were able to reduce their body weight by 4.5 kg and their systolic/diastolic blood pressures by 3.7 mmHg and 2.7 mmHg, respectively [19]. In another trial with 522 patients (aged 40–65 years) with diabetes type 2 and a BMI of ≥ 25 kg/m², participants of a two-year program that included dietary training and an endurance sports program achieved a significant reduction in systolic/diastolic blood pressure of 5 mmHg in each case [14]. In the present study, weight reduction (mean 7.1 kg) during rehabilitation was accompanied by a highly significant decrease in systolic and diastolic blood pressure of 12.8 mmHg (p<0.001) and 6.8 mmHg (p<0.001), respectively.

Heart rate is said to be an influencing factor in the development of cardiovascular diseases and is associated with body weight, visceral fat proportion, and BMI [20]. The positive correlation between weight-associated parameters and heart rate under resting conditions is likely due to a higher sympathetic activity [20]. In the present study collectively, a significant positive correlation was found between resting pulse and various weight-associated parameters such as BMI, weight reduction (%), and decrease of waist circumference. The heart rate at rest decreased very significantly by more than ten beats per minute.

In the German National Health Survey of 1998 and the DEGS-1 study conducted from 2008 to 2011, health-related life quality of a large number of probands (German National Health Survey: n=6964; DEGS study: n=8152) was analysed. The DEGS-1 study revealed that men and women suffering from chronic diseases estimate their personal health-related life quality as significantly lower than people not suffering from the said diseases. The life quality of obese persons determined with the SF-36 questionnaire diminished in all areas when compared to the German general population.

A comparison of the present data with data from the DEGS-1 study showed a highly reduced health-related life quality for patients at the beginning of the rehabilitation program in all areas. On a sex neutral basis, the extent of the reduction was about 30%. At the end of the rehabilitation program, patients estimated their life quality in all areas to be significantly higher. For some areas (e.g., vitality, social functioning, and emotional role), the patients reached the level of the german general population. The effect of weight reduction on the subjectively perceived life quality is likely due to changes in body scheme and to an enhanced self-esteem.

No control group was considered in this study. Also, the gender distribution was not balanced. Further the exclusion rate was quite high.

Obesity is divided into different degrees of severity and the accompanying diseases are always different. It must therefore be decided individually whether an outpatient obesity therapy is sufficient or an inpatient stay is necessary. The results of the present study clearly shows that the four-week inpatient rehabilitation program at the Eleonoren Clinic is suitable to achieve an initial weight reduction and to improve the physiological state of health and life quality. This outcome can serve as a suitable prerequisite for the post-clinic continuation of the acquired lifestyle changes in regard to diet and exercise.

BIA, Bioelectric Impedance Analysis; BMI, Body Mass Index; WHO, World Health Organization; NVS, Nationale Verzehrstudie; EWL, Excessive Weight Loss; ECG, Electrocardiogram; ACE, Angiotensin-Converting-Enzyme; HYDRA, Hypertension and Diabetes Risk Screening and Awareness; DEGS, Studie zur Gesundheit Erwachsener in Deutschland.

Ethics approval and consent to participate:

The project was examined and approved by the Ethics Committee of the University of Munich. Registration number: 546-13

www.ethikkommission.med.uni-muenchen.de