Bioimpedance analysis in a weight-loss programme during cardiac rehabilitation

Rationale:Bioimpedance is a quick, non-invasive method to assess body composition, to track changes in fat proportion during a weight-loss programme and to follow-up changes in body water proportion and shift between extra- and intracellular spaces. These parameters are of interest in a cardiac rehabilitation unit.

Methods: Patients were selected based on their willingness to participate in a weight-loss programme during their rehabilitation. Quadscan4000 was used to measure body composition. We used a balanced, low-fat diet based on the measured Basal Metabolic Rate. Beside the routine physical training, patients were advised to walk an extra 5km, monitored with a pedometer. Data were analysed with Student's paired T-test.

Results: Ten patients undertook the programme. Their mean age was 57±11 years. The mean BMI was proved to be 38.6at the start. The average weight-loss was 4% (p=0.01). The measured initial fat proportion was 46.8%, that declined significantly (p=0.01) to 44.5%. The lean body mass did not changed significantly, even a slight increase could be detected (52.2kg to 52.4kg). The BMI decreased significantly (p=0.01) to 37.3. The BFMI decreased from 18.3 to 16.5 (p=0.007), meanwhile the FFMI was stable. Patients daily walked on average 4km. They reached or exceeded the 5km limit in 30% of the days (min: 1.14km, max: 13.7km).

Conclusion: Patients who intended to loose weight could succeed with the help of professionals in a controlled environment. This initial change is crucial, because it demonstrates the result of efforts and it is a fix point that can be referred to in the later phase of weight-loss programmes. Bioimpedance analysis serves as control in adherence to the programme and raises the compliance of the patients.