Abstract
Background: To overcome the problem of a high prevalence of undiscovered or untreated arterial hypertension in people of working age, the effects of behavioral change counseling in occupational health (OH) services should be investigated. The technique of motivational interviewing (MI) to support health-related lifestyle changes by physicians and/or occupational nurses ('health coach') has been shown to be successful in patients with chronic diseases. In 2010, we planned a randomized controlled trial (RCT) with employees who suffer from mild arterial hypertension. A preliminary feasibility study was performed in a large manufacturing company in Germany. Methods: All employees with elevated blood pressure measured by the OH-service were invited to undergo validation by 30 self-measurements. Persons with validated elevated values and without medical treatment received either usual hypertension counseling (control group, CG) or intensified MI-counseling (intervention group, IG) by the occupational health physician. Subsequently, the IG received MI-support from the 'health coach' in four telephone counseling sessions. Assessed feasibility factors included organizational processes, the acceptance of the validation procedure and the MI-counseling, and as primary outcome for an RCT the extent to which participants made health-related changes to their lifestyles. Results: Initially, 299 individuals were included in Study Part A (screening). At the end of Study Part B (intervention), out of 34 participants with validated and non-treated mild hypertension, only 7 (IG) and 6 (CG) participants completed the intervention including documentation. The high drop-out rate was due to the frequent lack of willingness to perform the 30 self-measurements at home with their own equipment. Acceptance was little higher when we changed the method to two repeated measurements in the OH service. MI-counseling, especially by the health coach, was evaluated positively. Conclusions: Despite the promising counseling approach, the feasibility study showed that an RCT with previous screening in the operational setting can only be implemented with high financial and personnel effort to reach an appropriate number of subjects. This substantial result could only be achieved through this comprehensive feasibility study, which investigated all aspects of the planned future RCT.