Since participants in both groups are hospitalized in the same unit, to avoid contamination, participants in the placebo control group will receive the same intervention as those participants in the experimental group during their hospitalization. When discharged home, participants will receive an amount of time and attention (home visits by research assistants) that mimicked that received by the experimental group, but which is thought not to have any specific effect on the outcome measures. The activities during the home visits over a six-month period include playing cards or chess games, health advice on the prevention of influenza and healthy diet.