Reduction of Long-Term Care Dependence After an 8-Year Primary Care Prevention Program for Stroke and Dementia: The INVADE Trial

Abstract

Background: Stroke and dementia are the major causes for long-term care (LTC) dependence in old age. This intervention trial compared a multidomain prevention program for stroke and dementia with usual medical care in reducing the need for LTC.

Methods and results: The Intervention Project on Cerebrovascular Disease and Dementia in the District of Ebersberg (INVADE) was a general practice-based 8-year trial in 2 defined catchment areas in Upper Bavaria, Germany. All 11 317 insurants of a statutory health insurance plan who were ≥55 years of age and lived in the intervention district were offered the opportunity to participate in a prevention program; 3908 enrolled. The 13 301 insurants in the reference district received usual medical care. The intervention consisted of the systematic identification and evidence-based treatment of vascular risk factors. The primary clinical end point was incidence of LTC dependence according to external assessment by a special medical service in the framework of the statutory German LTC insurance. Age- and sex-specific incidence rates from the reference district were used to calculate the expected number of cases of LTC dependence under usual medical care. The expected number was compared with the observed number of cases in the intervention district. Analysis was by intention to treat. During the 5 years after completion of the recruitment period, significantly fewer incident cases of LTC dependence arose in the intervention district than expected (χ(2)=13.25; P<0.001). In women, the incidence was reduced by 10% (P<0.01). In men, the incidence was reduced by 9.6% (P<0.05).

Conclusions: Our results support the feasibility and effectiveness of a primary care prevention program for stroke and dementia to reduce the risk of developing LTC dependence.

Clinical trial registration: URL: http://www.clinicaltrials.gov. Unique identifier: NCT01107548. (J Am Heart Assoc. 2012;1:e000786 doi: 10.1161/JAHA.112.000786.).

Keywords: dementia; prevention; risk factors; stroke.

Figure 1.

Composition of the study population.

Figure 2.

Flow of participants in the intervention program.

Figure 3.

Cumulative numbers of observed and expected incident cases of LTC dependence during the years 2001 to 2008 in the intervention district (n=11 317 at the beginning of 2001).

Figure 4.

Numbers of observed and expected prevalent cases of LTC dependence at the end of each of the years 2001 to 2008 in the intervention district (n=11 317 at the beginning of 2001).